51.1. 1. H. Abu-Rub, J. Guzinski, Z. Krzeminski, H.A. Toliyat, "Advanced control of induction motor based on load angle estimation," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 5- 14, Feb. 2004. Full Text Link
Abstract: An advanced control system with load angle adjustment is introduced. The method is based on the action of a phase-locked loop, in which a position synchronization of two vectors to obtain a constant command angle between them is realized. In the system presented, the vectors are stator current and rotor flux. The load angle is kept constant by changing the position of stator current vector as a result of tuning its pulsation. Proportional-integral and fuzzy logic controllers are used to control the load angle. Because of using the load angle controller and simple relations for state variables, the proposed idea does not require exact speed measurement. The discussed control system is not sensitive to motor resistance variations. This idea is realized on a fixed-point digital signal processor and field-programmable gate arrays. Experimental results for the control system fed by a voltage-source inverter and controlled using a predictive current controller are presented.
51.1. 2. Ching-Guo Chen, Tian-Hua Liu, Ming-Tsan Lin, Chih-An Tai, "Position control of a sensorless synchronous reluctance motor," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 15- 25, Feb. 2004. Full Text Link
Abstract: This paper presents a novel position control for a sensorless synchronous reluctance drive system. By measuring the three-phase currents of the motor, a rotor position estimator is achieved. Then, a velocity estimator is derived from the estimated rotor position by using a state estimating technique. The estimated velocity tracks the real velocity well. Next, a robust position controller is designed to improve the transient and load disturbance responses. By using the proposed estimating techniques and control algorithm, a high-performance sensorless synchronous reluctance drive is obtained. A digital signal processor, TMS-320-C30, is used to execute the estimating and control algorithms. No hardware circuit or external signal is added as compared with the traditional drive system with an encoder or resolver. To evaluate the performance of the position control system, a moving table is connected with the drive system. The drive system can precisely control the moving table. Experimental results show that the proposed system has good performance. Several experimental results validate the theoretical analysis.
51.1. 3. Z.-J. Yang, K. Miyazaki, S. Kanae, K. Wada, "Robust position control of a magnetic levitation system via dynamic surface control technique," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 26- 34, Feb. 2004. Full Text Link
Abstract: This paper considers the position-tracking problem of a magnetic levitation system in the presence of modeling errors due to uncertainties of physical parameters. A robust nonlinear controller is designed to achieve excellent position-tracking performance. The recently developed dynamic surface control is modified and applied to the system under study, to over-come the problem of "explosion of terms" associated with the backstepping design procedure. Input-to-state stability of the control system is analyzed, and the advantages of the dynamic surface control technique over the conventional backstepping technique are verified through both theoretical and experimental studies.
51.1. 4. Ya-Fu Peng, Rong-Jong Wai, Chih-Min Lin, "Implementation of LLCC-resonant driving circuit and adaptive CMAC neural network control for linear piezoelectric ceramic motor," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 35- 48, Feb. 2004. Full Text Link
Abstract: In this paper, an adaptive cerebellar-model articulation computer (CMAC) neural network (NN) control system is developed for a linear piezoelectric ceramic motor (LPCM) that is driven by an LLCC-resonant inverter. The motor structure and LLCC-resonant driving circuit of an LPCM are introduced initially. The LLCC-resonant driving circuit is designed to operate at an optimal switching frequency such that the output voltage will not be influenced by the variation of quality factor. Since the dynamic characteristics and motor parameters of the LPCM are highly nonlinear and time varying, an adaptive CMAC NN control system is designed without mathematical dynamic model to control the position of the moving table of the LPCM drive system to achieve high-precision position control with robustness. In the proposed control scheme, the dynamic backpropagation algorithm is adopted to train the CMAC NN online. Moreover, to guarantee the convergence of output tracking error for periodic commands tracking, analytical methods based on a discrete-type Lyapunov function are utilized to determine the optimal learning-rate parameters of the CMAC NN. The effectiveness of the proposed driving circuit and control system is verified by experimental results in the presence of uncertainties, and the advantages of the proposed control system are indicated in comparison with a traditional integral-proportional position control system. Accurate tracking response and superior dynamic performance can be obtained due to the powerful online learning capability of the CMAC NN with optimal learning-rate parameters.
51.1. 5. A. Bunte, S. Beineke, "High-performance speed measurement by suppression of systematic resolver and encoder errors," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 49- 53, Feb. 2004. Full Text Link
Abstract: The subject of this paper is a method which suppresses systematic errors of resolvers and optical encoders with sinusoidal line signals. The proposed method does not require any additional hardware and the computational efforts are minimal. Since this method does not cause any time delay, the dynamic of the speed control is not affected. By means of this new scheme, dynamic and smooth running characteristics of drive systems are improved considerably.
Power Electronics
51.1. 6. D.B. Costa, C.M.C. Duarte, "The ZVS-PWM active-clamping CUK converter," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 54- 60, Feb. 2004. Full Text Link
Abstract: A CUK converter featuring clamping action, pulsewidth modulation, and soft-switching commutation is proposed to overcome the limitations of the conventional CUK converter. As the resonant circuits absorb almost all parasitic reactances of switches, including transistor output capacitances, this converter is suitable for high-frequency operation. Principle of operation, theoretical analysis, and simulation results are presented in this paper. Experimental results, taken from a laboratory prototype rated at 400 W, input voltage of 150 V, output voltage of 200 V, and operating at 100 kHz, are also presented. The efficiency obtained at full load of the power stage was 93%.
51.1. 7. Jianguo Liu, P. Pillay, H. Douglas, "Wavelet modeling of motor drives applied to the calculation of motor terminal overvoltages," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 61- 66, Feb. 2004. Full Text Link
Abstract: The wavelet is a powerful tool that has emerged for the calculation of power system transients. In this paper, a wavelet motor drive model is developed and applied to the overvoltage problem which occurs with high dv/dt inverters. This technique is fundamentally different from EMTP and Pspice, which are time-domain methods. Wavelet models of typical passive parameters are derived and then applied to the problem of motor terminal overvoltages, which occurs with long cable lengths. It is proved that the simulation results with wavelet modeling is faster in the solution of this complex, power system simulation problem. Additional insight is possible by examining the wavelet coefficients.
51.1. 8. S. Tamai, S. Murakami, R. Uchida, H. Akagi, "Control and performance of a self-commutated GTO converter operating in parallel with line-commutated thyristor converters," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 67- 73, Feb. 2004. Full Text Link
Abstract: Recently, static var generators (SVGs) or static synchronous compensators based on self-commutated converters have been put into practical use for the purpose of compensation for reactive power, power swings damping, and/or voltage control in power systems. The SVGs have also been applied to reduce voltage fluctuations appearing at high-speed train substations. When parallel resonance occurs between passive filters installed at a point of common coupling (PCC) and the power-system impedance existing upstream of the PCC, voltage/current harmonics are significantly amplified in the power system. This paper describes the control and performance for a self-commutated gate-turn-off (GTO) converter operating in parallel with conventional line-commutated thyristor converters. This hybrid power conversion system rated at more than dozens of MVA has an inductive load at the dc side. A bank of passive filters is connected not only for harmonic compensation of the line-commutated converters, but also as a constant leading reactive-power source. The GTO converter can control either leading or lagging reactive power so as to achieve unity power factor operation. In addition, it has the capability of damping out parallel resonance between the passive filters and the power-system impedance. This paper confirms the viability and effectiveness of the hybrid system by means of theory and computer simulation.
51.1. 9. D.A. Bennett, R.H. Selfridge, J.N. Harb, D.T. Comer, "A control circuit for a microsensor hybrid power supply," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 74- 80, Feb. 2004. Full Text Link
Abstract: This paper presents a simple low-power control circuit intended to manage the power within a remote autonomous microsystem hybrid power supply. A hybrid power supply has only recently been discussed in the literature as a microsystem power source solution. The power management circuitry, which is a key component within a hybrid power supply, has not been adequately explored. Although a variety of components could have been implemented, the control circuit in this paper was designed for a hybrid power supply that utilizes a Ni/Zn microbattery and silicon solar cell. The circuit also employs a shunt architecture powered only by the solar cell to minimize the overall energy consumption of the hybrid power supply. The control circuit consumes a maximum of 7 /spl mu/A and appropriately manages power even when the hybrid power supply is connected to a microsystem and is experiencing environmental variations. Details of the control circuit are discussed and simulations combined with experimental results demonstrate its performance.
51.1. 10. Xiangning He, Yan Deng, B.W. Williams, S.J. Finney, Zhaoming Qian, "A simple energy recovery circuit for high-power inverters with complete turn-on and turn-off snubbers," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 81- 88, Feb. 2004. Full Text Link
Abstract: This paper presents and analyzes an active energy recovery circuit for the inductive turn-on snubber and capacitive turn-off snubber used on high-power gate-turn-off thyristor inverters. The circuit performs as a simple switched-mode power supply and recovers the inductive and capacitive snubbers energy induced in power inverters back into the dc rail with the aid of an extra switch. The features and operation of the proposed circuit are given and supported by PSpice simulations and experimental results.
51.1. 11. H. Bodur, A.F. Bakan, "An improved ZCT-PWM DC-DC converter for high-power and frequency applications," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 89- 95, Feb. 2004. Full Text Link
Abstract: In this paper, an improved active resonant snubber cell that overcomes most of the drawbacks of the normal zero-current transition (ZCT) pulsewidth-modulation (PWM) dc-dc converter is proposed. This snubber cell is especially suitable for an insulated gate bipolar transistor (IGBT) PWM converter at high power and frequency levels. The converter with the proposed snubber cell can operate successfully with soft switching under light-load conditions and at considerably high frequencies. The operation principles, a detailed steady-state analysis, and a snubber design procedure of a ZCT-PWM buck converter implemented with the proposed snubber cell are presented. Theoretical analysis is verified with a prototype of a 5-kW and 50-kHz IGBT-PWM buck converter. Additionally, at 90% output power, the overall efficiency of the proposed soft switching converter increases to about 98% from the value of 91% in the hard-switching case.
51.1. 12. A.M. Omar, N.A. Rahim, S. Mekhilef, "Three-phase synchronous PWM for flyback converter with power-factor correction using FPGA ASIC design," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 96- 106, Feb. 2004. Full Text Link
Abstract: The design and development of a synchronous pulsewidth modulation (PWM) generator suitable for the three-phase flyback converter with transformer isolated and power-factor correction using a field-programmable gate array is proposed. The proposed three-phase synchronous PWM makes it possible for the converter to obtain the sinusoidal supply currents with a near-unity power factor. A high-frequency transformer is considered in the design to provide galvanic isolation and serves the dual role of inductor and transformer. Results are provided to demonstrate the effectiveness of the design.
51.1. 13. M. Eltabach, A. Charara, I. Zein, "A comparison of external and internal methods of signal spectral analysis for broken rotor bars detection in induction motors," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 107- 121, Feb. 2004. Full Text Link
Abstract: Like all mechanical devices, motors are subject to failures, which can sometimes lead to the shutting down of an entire industrial process. This paper looks at failure predictions in three-phase line-operated induction machines through spectral analysis or electric and electromagnetic signals. Fault characteristics frequencies generated in the estimated and the measured signal spectrum, as a result of mechanical abnormalities such as broken rotor bars, are analyzed. Spectral analyses of simple stator current, of the current's Park vector modulus, and or total and partial instantaneous electric powers are considered as external diagnosis. Internal methods of diagnosis are usually based on a mathematical model of the motor. This requires knowledge of the motor's electrical parameters, which are affected by a number of physical phenomena such as temperature variations, skin effects, core losses, and saturation. As internal diagnosis, we examine different approaches to the spectral analysis of electromagnetic torque computed by stator and rotor flux estimation. To this end, the open loop method, the Luenberger observer and the Kalman filter are employed. Finally, experimental results enable us to draw up a table of comparison of internal and external methods in the detection of rotor imperfections, using two criteria under different load levels.
51.1. 14. C. Branas, F.J. Azcondo, S. Bracho, "Study of output power variation due to component tolerances in LC/sub s/C/sub p/ resonant inverters applied to HPS lamp control," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 122- 131, Feb. 2004. Full Text Link
Abstract: The aim of this paper is to incorporate the analysis of component tolerance in the design criteria of resonant inverters applied to the control of high-pressure sodium (HPS) lamps. This method may also be considered for metal halide (MH) lamps. The design accepts a large load variation without exceeding the lamp power limits given by the standard. The analysis is focused on the selection of the most suitable value of the resonant network in order to achieve a good repeatability of the circuit performance. The study is based on the analysis of the lamp power sensitivity regarding the lamp aging and the tolerance of the circuit components. The proposed design is validated with experimental results and a statistical study by the Monte Carlo method.
51.1. 15. G.-M. Lee, Dong-Choon Lee, Jul-Ki Seok, "Control of series active power filters compensating for source voltage unbalance and current harmonics," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 132- 139, Feb. 2004. Full Text Link
Abstract: In this paper, a novel control scheme compensating for source voltage unbalance and current harmonics in series-type active power filter systems combined with shunt passive filters is proposed, which focuses on reducing the delay time effect required to generate the reference voltage. Using digital all-pass filters, the positive voltage sequence component out of the unbalanced source voltage is derived. The all-pass filter can give a desired phase shift and no magnitude reduction, unlike conventional low-or high-pass filters. Based on this positive-sequence component, the source phase angle and the reference voltage for compensation are derived. This method is easier to implement and to tune controller gains. In order to reduce the delay time effect in the voltage control loop, the reference voltage is predicted a sampling period ahead. The validity of the proposed control scheme has been verified by experimental results.
51.1. 16. Byungcho Choi, Jaehyun Nho, Honnyong Cha, Taeyoung Ahn, Seungwon Choi, "Design and implementation of low-profile contactless battery charger using planar printed circuit board windings as energy transfer device," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 140- 147, Feb. 2004. Full Text Link
Abstract: This paper paper presents the practical details involved in the design and implementation of a contactless battery charger that employs a pair of neighboring printed circuit board (PCB) windings as a contactless energy transfer device. A prototype contactless battery charger developed for application with cellular phones is used as an example to address the design considerations for the PCB windings and energy transfer circuit, plus demonstrates the performance of the contactless charger adapted to a practical application system.
51.1. 17. Chwei-Sen Wang, G.A. Covic, O.H. Stielau, "Power transfer capability and bifurcation phenomena of loosely coupled inductive power transfer systems," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 148- 157, Feb. 2004. Full Text Link
Abstract: Loosely coupled inductive power transfer (LCIPT) systems are designed to deliver power efficiently from a stationary primary source to one or more movable secondary loads over relatively large air gaps via magnetic coupling. In this paper, a general approach is presented to identify the power transfer capability and bifurcation phenomena (multiple operating modes) for such systems. This is achieved using a high order mathematical model consisting of both primary and secondary resonant circuits. The primary compensation is deliberately designed to make the primary zero phase angle frequency equal the secondary resonant frequency to achieve maximum power with minimum VA rating of the supply. A contactless electric vehicle battery charger was used to validate the theory by comparing the measured and calculated operational frequency and power transfer. For bifurcation-free operation, the power transfer capability and controllability are assured by following the proposed bifurcation criteria. Where controllable operation within the bifurcation region is achievable, a significant increase in power is possible.
51.1. 18. L. Helle, K.B. Larsen, A.H. Jorgensen, S. Munk-Nielsen, F. Blaabjerg, "Evaluation of modulation schemes for three-phase to three-phase matrix converters," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 158- 171, Feb. 2004. Full Text Link
Abstract: This paper presents a method for evaluating different modulation schemes employed with three-phase to three-phase matrix converters. The evaluation method addresses three important modulator characteristics: the output waveform quality, the input waveform quality and the switching losses associated with the modulation schemes. The method is used to evaluate four different modulation strategies, all based on the direct space-vector modulation approach. Further, regarding the switching losses, the paper proposes a new space-vector approach by which the switching losses can be reduced by 15%-35%, depending on the output load angle. This new modulation approach is applicable whenever the output voltage reference is below half the input voltage and the output voltage quality is then superior to that of the conventional space vector modulation scheme. The functionality of the new modulation scheme is validated by both simulations and experimental results and compared to waveforms obtained by using exiting space vector modulation schemes. The output voltage of the proposed scheme turns out to be comparable to the best of the conventional schemes while the input current is more distorted.
Emerging Technology
51.1. 19. F.H.F. Leung, H.K. Lam, S.H. Ling, P.K.S. Tam, "Optimal and stable fuzzy controllers for nonlinear systems based on an improved genetic algorithm," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 172- 182, Feb. 2004. Full Text Link
Abstract: This paper addresses the optimization and stabilization problems of nonlinear systems subject to parameter uncertainties. The methodology is based on a fuzzy logic approach and an improved genetic algorithm (GA). The TSK fuzzy plant model is employed to describe the dynamics of the uncertain nonlinear plant. A fuzzy controller is then obtained to close the feedback loop. The stability conditions are derived. The feedback gains of the fuzzy controller and the solution for meeting the stability conditions are determined using the improved GA. In order to obtain the optimal fuzzy controller, the membership functions are further tuned by minimizing a defined fitness function using the improved GA. An application example on stabilizing a two-link robot arm will be given.
51.1. 20. S. Wu, T.W.S. Chow, "Induction machine fault detection using SOM-based RBF neural networks," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 183- 194, Feb. 2004. Full Text Link
Abstract: A radial-basis-function (RBF) neural-network-based fault detection system is developed for performing induction machine fault detection and analysis. Four feature vectors are extracted from power spectra of machine vibration signals. The extracted features are inputs of an RBF-type neural network for fault identification and classification. The optimal network architecture of the RBF network is determined automatically by our proposed cell-splitting grid algorithm. This facilitates the conventional laborious trial-and-error procedure in establishing an optimal architecture. In this paper, the proposed RBF machine fault diagnostic system has been intensively tested with unbalanced electrical faults and mechanical faults operating at different rotating speeds. The proposed system is not only able to detect electrical and mechanical faults, but the system is also able to estimate the extent of faults.
Robotics And Vision
51.1. 21. W.L. Xu, S. Yue, "Pre-posed configuration of flexible redundant robot manipulators for impact vibration alleviating," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 195- 200, Feb. 2004. Full Text Link
Abstract: In this paper, kinematics redundancy of a flexible redundant manipulator (FRM) is employed to alleviate the impact vibration resulting from objects grasping. A vibration-alleviating measure (VAM) of the FRM, and a vibration-alleviating ellipsoid (VAE) with respect to the measure are defined. A method to determine the pre-posed configuration of an FRM is presented based on the defined VAM and VAE. A finite-element model is used to describe the FRM's dynamics incorporating the grasped object. Simulation conducted on a planar FRM shows that the FRM experiences relatively less impact vibration at the pre-posed configuration determined by using the presented method.
51.1. 22. Rong-Jong Wai, Meng-Chang Lee, "Intelligent optimal control of single-link flexible robot arm," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 201- 220, Feb. 2004. Full Text Link
Abstract: This paper addresses the design and properties of an intelligent optimal control for a nonlinear flexible robot arm that is driven by a permanent-magnet synchronous servo motor. First, the dynamic model of a flexible robot arm system with a tip mass is introduced. When the tip mass of the flexible robot arm is a rigid body, not only bending vibration but also torsional vibration are occurred. In this paper, the vibration states of the nonlinear system are assumed to he unmeasurable, i.e., only the actuator position can be acquired to feed into a suitable control system for stabilizing the vibration states indirectly. Then, an intelligent optimal control system is proposed to control the motor-mechanism coupling system for periodic motion. In the intelligent optimal control system a fuzzy neural network controller is used to learn a nonlinear function in the optimal control law, and a robust controller is designed to compensate the approximation error. Moreover, a simple adaptive algorithm is proposed to adjust the uncertain bound in the robust controller avoiding the chattering phenomena. The control laws of the intelligent optimal control system are derived in the sense of optimal control technique and Lyapunov stability analysis, so that system-tracking stability can be guaranteed in the closed-loop system. In addition, numerical simulation and experimental results are given to verify the effectiveness of the proposed control scheme.
51.1. 23. S. Katsura, K. Ohnishi, "Human cooperative wheelchair for haptic interaction based on dual compliance control," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 221- 228, Feb. 2004. Full Text Link
Abstract: A human and a robot will carry out a task which is not attainable by themselves. In particular, a human recognizes environment and plans his trajectory without collision with obstacles. On the other hand, a robot generates a controlled force more than a human. In this paper, the best combination of human ability and robot capacity is considered. Based on force commands from a human, a robot supports it A reaction torque observer is implemented in a robot to observe an environmental disturbance. Environmental disturbance is classified into translational and rotational direction modes. As a result, adaptive force control in each mode is attained. Dual compliance control is applied to a wheelchair. A wheelchair that has the abilities of power-assist and relaxation of contact force is developed in this paper. As a result, operationality and stability are improved. The numerical and experimental results show the viability of the proposed method.
51.1. 24. K. Morioka, Joo-Ho Lee, H. Hashimoto, "Human-following mobile robot in a distributed intelligent sensor network," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 229- 237, Feb. 2004. Full Text Link
Abstract: The robots that will be needed in the near future are human-friendly robots that are able to coexist with humans and support humans effectively. To realize this, humans and robots need to be in close proximity to each other as much as possible. Moreover, it is necessary for their interactions to occur naturally. It is desirable for a robot to carry out human following, as one of the human-affinitive movements. The human-following robot requires several techniques: the recognition of the target human, the recognition of the environment around the robot, and the control strategy for following a human stably. In this research, an intelligent environment is used in order to achieve these goals. An intelligent environment is a space in which many sensors and intelligent devices are distributed. Mobile robots exist in this space as physical agents providing humans with services. A mobile robot is controlled to follow a walking human using distributed intelligent sensors as stably and precisely as possible. The control law based on the virtual spring model is proposed to mitigate the difference of movement between the human and the mobile robot. The proposed control law is applied to the intelligent environment and its performance is verified by the computer simulation and the experiment.
Letters To The Editor
51.1. 25. P. Sooraksa, G. Chen, "On comparison of hybrid fuzzy PI plus conventional D controller versus fuzzy PI+D controller," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 238- 239, Feb. 2004. Full Text Link
Abstract: This letter points out that a comparison given in an earlier paper by Er and Sun (ibid. vol. 48, pp. 1109-1117, 2001) is incorrect. The fuzzy PI+D controller designed by Misir et al. ( Fuzzy Sets Syst. vol. 79, pp. 297-314, 1996) is overall better than the hybrid fuzzy PI plus conventional D controller designed by Er and Sun.
51.2. 26. P.W. Wheeler, J. Clare, L. Empringham, "Enhancement of matrix converter output waveform quality using minimized commutation times," Trans. on Industrial Electronics, vol. 51, no. 1, pp. 240- 244, Feb. 2004. Full Text Link
Abstract: This letter introduces a new concept in current commutation for matrix converters that minimizes the commutation time and, hence, enhances the output waveform quality. This commutation technique overcomes all the waveform quality problems associated with dead times in inverter-based circuits without the need for compensation. Practical results from a 10-kVA matrix converter are presented. Access to the journal on IEEE XPLOREIE Transactions Home Page
Special Section Papers on Automotive
Electronic Systems
51.2. 1. F. Cuesta, F. Gomez-Bravo, A. Ollero, "Parking maneuvers of industrial-like electrical vehicles with and without trailer," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 257- 269, April 2004. Full Text Link
Abstract: Maneuvering autonomous vehicles in constrained environments is not a trivial task. This paper concentrates in the practical maneuvering of electrical vehicles. The autonomous vehicles considered in the paper, ROMEO-3R and ROMEO-4R, have been developed at the University of Seville, Seville, Spain, as the result of the adaptation of a tricycle and a car-like conventional electrical vehicles for transportation of people, respectively. Moreover, maneuvering of ROMEO-4R backing up a trailer has also been considered. A particular maneuver, namely, autonomous parallel parking, has been used to illustrate the application of the presented methods to different electrical vehicles.
51.2. 2. R. Daily, D.M. Bevly, "The use of GPS for vehicle stability control systems," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 270- 277, April 2004. Full Text Link
Abstract: This paper presents a method for using global positioning system (GPS) velocity measurements to improve vehicle lateral stability control systems. GPS can be used to calculate the sideslip angle of a vehicle without knowing the vehicle model. This measurement is combined with other traditional measurements to control the lateral motion of the vehicle. Noise estimates are provided for all measurement systems to allow the sensors to be accurately represented. Additionally, a method to calculate the lateral forces at the tires is presented. It is shown that the tire estimation algorithm performs well outside the linear region of the tire. Results for the controller and force calculations are shown using a nonlinear model to simulate the vehicle and the force calculations are validated with experimental measurements on a test vehicle.
51.2. 3. J. Stephant, A. Charara, D. Meizel, "Virtual sensor: application to vehicle sideslip angle and transversal forces," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 278- 289, April 2004. Full Text Link
Abstract: This paper compares four observers (virtual sensors) of vehicle sideslip angle and lateral forces. The first is linear and uses a linear vehicle model. The remaining observers use an extended nonlinear model. The three nonlinear observers are: extended Luenberger observer, extended Kalman filter and sliding-mode observer. Modeling, model simplification, and observers are described, and an observability analysis is performed for the entire vehicle trajectory. The paper also deals with three different sets of sensors to see the impact of observers results. Comparison is first done by simulation on a valid vehicle simulator, and then observers are used on experimental data. Our study shows that observers are more accurate than simple models as regards unmeasurable variables such as sideslip angle and transversal forces. It also shows that speed of center of gravity is not an indispensable variable here.
51.2. 4. M. Parmar, J.Y. Hung, "A sensorless optimal control system for an automotive electric power assist steering system," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 290- 298, April 2004. Full Text Link
Abstract: This paper considers the analysis and design of a double-pinion-type electric power assist steering (EPAS) control system. A simplified model of the augmented steering assembly-electric motor system is developed using Lagrangian dynamics, and an optimal controller structure for the model is proposed. Three main advances to the state of the art are presented in this paper. First, a state-space design model is used rather than an input-output model. A state-space formulation for a system model that incorporates motor electrical dynamics is obtained with the assist motor angular position as the output. Second, linear quadratic regulator (LQR) and Kalman filter techniques are employed to arrive at an optimal controller for the EPAS system. The selection of weighting coefficients for the LQR cost function is discussed. Finally, the authors present a control strategy that eliminates the steering column torque sensor, a critical component in existing EPAS controller designs. The proposed control strategy presents an opportunity to improve EPAS system performance and also reduce system cost and complexity.
51.2. 5. M. Montanari, F. Ronchi, C. Rossi, A. Tonielli, "Control of a camless engine electromechanical actuator: position reconstruction and dynamic performance analysis," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 299- 311, April 2004. Full Text Link
Abstract: Camless internal combustion engines offer major improvements over traditional engines in terms of efficiency, maximum torque and power, and pollutant emissions. Electromechanical valve actuators are very promising in this context, but they present significant control problems. Further, to keep system cost at an acceptable level, a control system without a valve position sensor needs to be adopted. Low valve seating velocity, small transition time for valve opening and closing, and unavailability of position sensor are conflicting objectives that need to be jointly considered. In this paper, a control system architecture is presented, capable of dealing with all these issues. It is shown that a position tracking controller is needed: a key point is the design of the reference trajectory to be tracked. Actuator physical limitations strongly influence the feasible trajectory when low valve seating velocity is required, thus affecting valve transition time. Owing to the same limitations, valve electromagnets have to be energized for a significant part of the trajectory, thus allowing valve position reconstruction starting from electrical measurements only. A method for position reconstruction is presented, which makes use of auxiliary coils to reconstruct electromagnets fluxes; it is shown via sensitivity analysis that the functional characteristics of position reconstruction and its accuracy are compatible with the required applications. The trajectory design is then addressed as an optimization problem that explicitly considers the tradeoff between fast dynamic performance and system robustness. The solution of this optimization problem enlightens the limitations on achievable dynamic performance, which are presented and discussed.
51.2. 6. Junha Kim, Jinhwan Jung, Kwanghee Nam, "Dual-inverter control strategy for high-speed operation of EV induction motors," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 312- 320, April 2004. Full Text Link
Abstract: An integrated starter/alternator (ISA) is normally designed to have high pole structure (10-14 poles) for high starting torque. However, its back electromotive force (EMF) at the peak revolutions per minute should be less than its battery voltage for the power flow control. For example, the back-EMF of a 12-pole ISA should be 42 V at 6000 r/min. These types of conflicting requirements lead to a nonclassical motor design that has extremely large field-weakening range (8:1/spl sim/10:1). In this paper, we are considering the use of an induction machine instead of a permanent synchronous machine. As an idea for solving the voltage limit problem, two inverters are utilized with an objective of sharing the required voltage. The secondary inverter only takes care of the reactive voltage component that grows very fast in high-speed operation. Therefore, an extra voltage source is not required for the secondary inverter. Only a capacitor bank suffices for the secondary inverter.
51.2. 7. W.G. Koellner, G.M. Brown, J. Rodriguez, J. Pontt, P. Cortes, H. Miranda, "Recent advances in mining haul trucks," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 321- 329, April 2004. Full Text Link
Abstract: Electric mining haul trucks are one of the most challenging applications of power electronics in automotive systems. This paper presents some advances in very-high-power trucks used in copper mines. The special operational and environmental requirements for this application are highlighted. It is established that the use of inverter-fed three-phase induction motors with vector control is the preferred solution to reach the required high starting torque and good dynamic performance required by these vehicles. Packaging is a key issue and special attention is dedicated to the forced-air cooling system, because the air has a high dust level including conductive and corrosive materials. The truck's high-performance electric retarding system is described along with a novel use of trolley lines in a diesel boost mode as a way to increase the power and speed of the truck and reduce fuel consumption. Advanced features like remote monitoring, the use of global positioning systems and Internet diagnostics and troubleshooting are also discussed. The paper clearly shows that modern electric haul trucks are highly sophisticated systems that make full use of advances in modern technologies to increase safety and productivity levels.
Drive Control
51.2. 8. Ching-Chih Tsai, Chih-Hung Huang, "Model reference adaptive predictive control for a variable-frequency oil-cooling machine," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 330- 339, April 2004. Full Text Link
Abstract: This paper develops methodologies and techniques for the design, analysis, and implementation of a model reference adaptive predictive temperature controller for a variable-frequency oil-cooling machine, suited for cooling high-speed machine tools. The oil-cooling process is modeled experimentally as a first-order system model with a time delay and its system parameters are identified using the recursive least-square method. Based on this model, a model reference adaptive predictive controller is proposed for achieving set-point tracking and robustness. A real-time model reference adaptive predictive control algorithm is then presented and implemented utilizing a stand-alone digital signal processor TMS320F243 from Texas Instruments Incorporated. The experimental results show that the proposed control method is proven capable of giving satisfactory performance under set-point changes, fixed loads, and load changes.
51.2. 9. A.G. Loukianov, J.M. Canedo, V.I. Utkin, J. Cabrera-Vazquez, "Discontinuous controller for power systems: sliding-mode block control approach," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 340- 353, April 2004. Full Text Link
Abstract: Based on the complete model of the plant, a sliding-mode stabilizing controller for synchronous generators is designed. The block control approach is used in order to derive a nonlinear sliding surface, on which the mechanical dynamics are linearized. This combined approach enables us to compensate the inherent nonlinearities of the generator and to reject high-level external disturbances. A nonlinear observer is designed for estimation of the rotor fluxes and mechanical torque.
51.2. 10. N. Bonnail, D. Tonneau, F. Jandard, G.-A. Capolino, H. Dallaporta, "Variable structure control of a piezoelectric actuator for a scanning tunneling microscope," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 354- 363, April 2004. Full Text Link
Abstract: Scanning probe microscopes are now widely used in the field of material science and engineering for surface imaging at atomic scale. Their principle is based on the surface probing by a sharp tip approached at a nanometric distance of the surface. The probe is fixed to piezoelectric actuators allowing its displacement above the surface. An electronic command of a scanning tunneling microscope (STM) has been designed and tested. The regulation feedback loop of the tunnel current includes an integral controller, as is the case in commercial equipment. An extra control by variable-structure system has been implemented on this electronic command. Its principle is based on the commutation of the feedback sign. The effect on the system performance of the variable structure control is presented and discussed. An STM head has been modeled and all the model parameters have been determined. The model has been validated by comparison of the experimental and simulated responses of the system under excitation.
51.2. 11. A. Damiano, G.L. Gatto, I. Marongiu, A. Pisano, "Second-order sliding-mode control of DC drives," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 364- 373, April 2004. Full Text Link
Abstract: One of the most recent topics in variable-structure systems theory is represented by the second-order sliding-mode control (2-SMC) methodology. This approach guarantees the same robustness and dynamic performance of traditional first-order SMC algorithms, and, at the same time, attenuates the chattering phenomenon, which is the main drawback in the actual implementation of this technique. In the present paper, a recently-proposed 2-SMC algorithm is used to synthesize a robust dc-drive control system which does not require current feedback and demands only rough information about the actual motor parameters. Stability and performance are analyzed, and an experimental comparison with a proportional-integral-based control scheme is reported.
51.2. 12. Jin-Woo Ahn, Sung-Jun Park, Dong-Hee Lee, "Hybrid excitation of SRM for reduction of vibration and acoustic noise," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 374- 380, April 2004. Full Text Link
Abstract: The inherent simplicity, ruggedness, and low cost of a switched reluctance motor (SRM) makes it a viable candidate for various general-purpose adjustable-speed applications such as industrial and home appliances. The primary disadvantage of an SRM is the vibration and acoustic noise compared with that of conventional machines. The main source of vibration in the SR drive is generated by rapid change of radial magnetic force when phase current is extinguished during commutation action. In this paper, a hybrid excitation method with C-dump inverter is proposed to reduce vibration and acoustic noise in the SR drive. The hybrid excitation has two-phase excitation by long dwell angle as well as conventional one-phase excitation. The vibration and acoustic noise are reduced because the scheme reduces abrupt change of excitation level by distributed and balanced excitation.
51.2. 13. Chunxiang Wang, Yongzhang Wang, Ruqing Yang, Hua Lu, "Research on precision tension control system based on neural network," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 381- 386, April 2004. Full Text Link
Abstract: In this paper, the closed-loop tension control system, with industrial control computer as the core, direct current torque motor as the actuator, equipped with tension sensor of real-time feedback filament tension change, is researched and manufactured. The theory of a neural network is applied on the system, and this method overcame the shortcomings of the traditional proportional-integral-derivative control method, and effectively weakened the coupling action between the velocity and tension of the tension control system. Some simulation results indicated the favorable effect of the control algorithm.
51.2. 14. P. Baranyi, "TP model transformation as a way to LMI-based controller design," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 387- 400, April 2004. Full Text Link
Abstract: The main objective of this paper is to propose a numerical controller design methodology. This methodology has two steps. In the first step, tensor product (TP) model transformation is applied, which is capable of transforming a dynamic system model, given over a bounded domain, into TP model form, including polytopic or Takagi-Sugeno model forms. Then, in the second step, Lyapunov's controller design theorems are utilized in the form of linear matrix inequalities (LMIs). The main novelty of this paper is the development of the TP model transformation of the first step. It does not merely transform to TP model form, but it automatically prepares the transformed model to all the specific conditions required by the LMI design. The LMI design can, hence, be immediately executed on the result of the TP model transformation. The secondary objective of this paper is to discuss that representing a dynamic model in TP model form needs to consider the tradeoff between the modeling accuracy and computational complexity. Having a controller with low computational cost is highly desired in many cases of real implementations. The proposed TP model transformation is developed and specialized for finding a complexity minimized model according to a given modeling accuracy. Detailed control design examples are given.
Power Electronics
51.2. 15. G. Escobar, A.M. Stankovic, P. Mattavelli, "An adaptive controller in stationary reference frame for D-statcom in unbalanced operation," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 401- 409, April 2004. Full Text Link
Abstract: This paper presents a passivity-based controller for a Distribution Static synchronous Compensator (D-Statcom) aimed at compensating reactive power and unbalanced harmonics in the general case of distorted and unbalanced source voltages and load currents. The proposed approach is based on the measurements of line currents, and ensures precise compensation for selected harmonics. Moreover, in order to compensate for the unavoidable uncertainty in certain system parameters, adaptation is added to the passivity-based controller. One of the major advantages of the proposed solution compared to conventional alternatives is that we are able to perform precise tracking (including higher order harmonics) even in the presence of a relatively low switching frequency, i.e., in the presence of an inverter with limited bandwidth. Simulation and experimental results are provided to illustrate the merits of our solution.
51.2. 16. K.K. Tse, B.M.T. Ho, H.S.-H. Chung, S.Y.R. Hui, "A comparative study of maximum-power-point trackers for photovoltaic panels using switching-frequency modulation scheme," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 410- 418, April 2004. Full Text Link
Abstract: A comparative study of the maximum power point trackers using a switching-frequency modulation scheme (SFMS) for photovoltaic panels is presented. Some commonly used dc/dc converters, which are applied for the power conversion stage of those trackers, will be examined. Method of locating the maximum power point (MPP) is based on injecting a small-signal sinusoidal perturbation into the switching frequency of the converter and comparing the ac component and the average value of the panel's terminal voltage. Apart from not requiring sophisticated computation of the panel power, this SFMS does not approximate the panel characteristics and can globally locate the MPP under wide insolation conditions. Tracking capability of the converters under investigation will be compared, using a 10-W solar panel with a controlled experimental setup. Theoretical predictions will be verified with experimental results. Operating characteristics at steady state and in large-signal change of the insolation (incident solar radiation) level will be studied.
51.2. 17. M. Lopez, L.G. de Vicuna, M. Castilla, P. Gaya, O. Lopez, "Current distribution control design for paralleled DC/DC converters using sliding-mode control," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 419- 428, April 2004. Full Text Link
Abstract: This paper shows the analysis and design of a parallel-connected converter system using sliding mode control techniques. The design is particularised for a system that consists of N boost converters and a current feedback loop based on a proportional-integral compensator of the output voltage error. The paper emphasises the advantages of the sliding-mode control over the classic design method based on small-signal models, thus providing an effective and robust means of controlling nonlinear multi-input converters. The design is based on the Utkin conditions, which permit us to know the regions under which a sliding mode exists. This fact allows us to design the compensator and to introduce some modifications in the control loop that avoids input-current overshoots during the system startup. Simple design expressions are obtained and verified with simulation and experimental results, thus showing the improvements achieved with the proposed modifications.
51.2. 18. H.Y. Kanaan, H. Fortin-Blanchette, K. Al-Haddad, R. Chaffai, L. Duguay, F. Fnaiech, "Linear control design for a current-injection-based three-phase unity-power-factor rectifier," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 429- 438, April 2004. Full Text Link
Abstract: In this paper, a new control strategy based on the pulsewidth-modulation technique is proposed and applied to an active-current-injection-based unity-power-factor three-phase ac-dc converter. The control circuit of the converter consists of a multivariable inner current regulator and an outer voltage regulator. Based on linear control techniques, the control circuit has been designed. Averaging techniques are used to derive a linear small-signal model of the converter in the frequency domain. Numerical simulations using the Power System Blockset tool of Matlab/Simulink highlight the performance of the proposed control scheme. Experimental results obtained on a 2-kW prototype validate the theoretical approach described in the paper.
51.2. 19. R.L. de Araujo Ribeiro, C.B. Jacobina, E.R.C. da Silva, A.M.N. Lima, "Fault-tolerant voltage-fed PWM inverter AC motor drive systems," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 439- 446, April 2004. Full Text Link
Abstract: This paper shows how to integrate fault compensation strategies into two different types of configurations of induction motor drive systems. The proposed strategies provide compensation for open-circuit and short-circuit failures occurring in the converter power devices. The fault compensation is achieved by reconfiguring the power converter topology with the help of isolating and connecting devices. These devices are used to redefine the post-fault converter topology. This allows for continuous free operation of the drive after isolation of the faulty power switches in the converter. Experimental results demonstrate the validity of the proposed systems.
51.2. 20. M. Malinowski, M. Jasinski, M.P. Kazmierkowski, "Simple direct power control of three-phase PWM rectifier using space-vector modulation (DPC-SVM)," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 447- 454, April 2004. Full Text Link
Abstract: This paper proposes a novel and simple direct power control of three-phase pulsewidth-modulated (PWM) rectifiers with constant switching frequency using space-vector modulation (DPC-SVM). The active and reactive powers are used as the pulse width modulated (PWM) control variables instead of the three-phase line currents being used. Moreover, line voltage sensors are replaced by a virtual flux estimator. The theoretical principle of this method is discussed. The steady-state and dynamic results of DPC-SVM that illustrate the operation and performance of the proposed system are presented. It is shown that DPC-SVM exhibits several features, such as a simple algorithm, good dynamic response, constant switching frequency, and particularly it provides sinusoidal line current when supply voltage is not ideal. Results have proven excellent performance and verify the validity of the proposed system.
51.2. 21. Chongming Qiao, Taotao Jin, K.M. Smedley, "One-cycle control of three-phase active power filter with vector operation," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 455- 463, April 2004. Full Text Link
Abstract: Active power filters (APFs) provides an effective measure to eliminate the power line harmonic/reactive currents generated by nonlinear loads or by distributed energy sources that are connected to the grid. Active power filters are typically connected in parallel to the harmonic/reactive current sources and cancel the harmonic/reactive components in the line current so that the current flow into and from the grid is sinusoidal and in phase with the grid voltage. Since the APFs process only the harmonic/reactive power, their power-handling capability can be much higher than that of the cascade power-factor-correction methods. In this paper, the one-cycle control method is extended to control three-phase APFs. The proposed control approach employs one integrator with reset along with several logic and linear components to control a voltage-source converter to achieve three-phase unity power factor for the current to and from the power grid. No multipliers or sensors for the load current and the APF inductor current are required. Furthermore, there is no need to calculate the reference for controlling APF inductor current so that complicated digital computation is eliminated. The operation switching frequency is constant that is desirable for industrial applications. The proposed control approach features great simplicity, excellent harmonic/reactive current cancellation, and solid stability. It is a cost-effective solution for power quality control for electronic equipment, buildings, industrial facilities, ships, airplanes, distributed power generation stations, etc. All findings are supported by experimental results.
Emerging Technology
51.2. 22. K.F. Leung, F.H.F. Leung, H.K. Lam, S.H. Ling, "On interpretation of graffiti digits and characters for eBooks: neural-fuzzy network and genetic algorithm approach," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 464- 471, April 2004. Full Text Link
Abstract: This paper presents the rule optimization, tuning of the membership functions, and optimization of the number of fuzzy rules, of a neural-fuzzy network (NFN) using a genetic algorithm (GA). The objectives are achieved by training a proposed NFN with rule switches. The proposed NFN and GA are employed to interpret graffiti number inputs and commands for electronic books (eBooks).
51.2. 23. Chin Tsu Yen, Wan-de Weng, Yen Tsun Lin, "FPGA realization of a neural-network-based nonlinear channel equalizer," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 472- 479, April 2004. Full Text Link
Abstract: The software simulation as well as the hardware implementation of equalizers for transmissions through nonlinear communication channels based on artificial neural networks structure is presented in this paper. We consider four-quadrature-amplitude-modulation technique as an example and compare the performance of two different structures of equalizer, namely, the linear least-mean-square-based equalizer (LIN) and the functional link artificial neural networks (FLANN). The learning curve and symbol error rate for the two structures are respectively evaluated by computer simulation. Besides, the systems have been implemented using field-programmable-gate-array devices. As FLANN uses functions to expand the dimensionality of the input signals, it has about the same system complexity as LIN. But FLANN can achieve fast processing speed under parallel processing structure. Simulation results have demonstrated that FLANN presents much better error performance than LIN, especially when the communication channel is highly nonlinear.
Robotics And Vision
51.2. 24. G. Ginesu, D.D. Giusto, V. Margner, P. Meinlschmidt, "Detection of foreign bodies in food by thermal image processing," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 480- 490, April 2004. Full Text Link
Abstract: This paper deals with the problem of detection of foreign bodies in food. A new method for inspecting food samples is presented, using thermographic images to detect foreign bodies that are not detectable using conventional methods. At first, the basic background of thermography is given. Then, experiments to obtain well-contrasted thermographic images of different food and foreign bodies are discussed. The main part of the present paper introduces specific image processing methods that show a good recognition power of foreign bodies within food. Results achieved with a small set of test images are presented. The results are promising and the methods work even on some poorly contrasted images. To compare the different image processing and recognition methods, a quality index is defined. On the test images the success of the presented methods is shown and the difference in recognition results can be measured using the introduced quality index.
51.2. 25. D. Bi, Y.F. Li, S.K. Tso, G.L. Wang, "Friction modeling and compensation for haptic display based on support vector machine," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 491- 500, April 2004. Full Text Link
Abstract: As the presence of friction in a haptic display device seriously affects its performance, proper compensation of the frictional effects in such a device is of practical importance for advanced virtual reality applications where haptic display plays a critical role. This paper addresses the issue of friction modeling and compensation for haptic control system designs. A new method based on the Support Vector Machine (SVM) is developed in a controller design based on a two-port network to achieve accurate haptic display. The approximation model of friction is established offline through SVM learning and is used for online feed forward friction compensation. The advantages of this novel method are demonstrated through the experiments performed.
51.2. 26. T. Muraoka, H. Ikeda, "Selection of display devices used at man-machine interfaces based on human factors," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 501- 506, April 2004. Full Text Link
Abstract: The display devices used in intelligent machines are very important to exchange information between the operators and the machines online. New selection methods for the display devices used at the man-machine interfaces are proposed based on the results of both the electronic Landolt's ring test and the electronic stress test. The electronic Landolt's ring test checks the degradation of the visual accommodation during the contiguous visual data terminal (VDT) operation, and the electronic stress test checks the efficiency changes of the practical work during the VDT operation. The electronic Landolt's ring and electronic stress tests were respectively confirmed to be useful for selecting the display devices used at man-machine interfaces. In addition, the combination of these two test methods is believed to be utilized for the proper selection of the display devices used at man-machine interfaces in the intelligent machines.
Letters To The Editor
51.2. 27. Kyu-Wang Lee, Doo-Hee Jung, In-Joong Ha, "An online identification method for both stator resistance and back-EMF coefficient of PMSMs without rotational transducers," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 507- 510, April 2004. Full Text Link
Abstract: This letter describes an effective online method for identifying both the stator resistance and the back-electromotive-force (EMF) coefficient of a permanent-magnet synchronous motor (PMSM) without rotational transducers. Using only the information of stator currents and voltages, it can provide fairly good identification accuracy under various load conditions and can be easily incorporated into most sensorless speed control schemes proposed in the prior literature.
51.2. 28. M. Karimi-Ghartemani, H. Karimi, M.R. Iravani, "A magnitude/phase-locked loop system based on estimation of frequency and in-phase/quadrature-phase amplitudes," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 511- 517, April 2004. Full Text Link
Abstract: This paper introduces a new phase-locked loop (PLL) system. The proposed system provides the dominant frequency component of the input signal and estimates its frequency. The mechanism of the proposed PLL is based on estimating in-phase and quadrature-phase amplitudes of the desired signal and, hence, has application advantages for communication systems which employ quadrature modulation techniques. The studies demonstrate that the proposed PLL also provides a superior performance for power system applications. Derivation of the mathematical model and theoretical stability analysis of the proposed PLL are carried out using dynamical systems theory. Advantages of the proposed PLL over the conventional PLLs are its capability of providing the fundamental component of the input signal which is not only locked in phase but also in amplitude to the actual signal while providing an estimate of its frequency. Computer simulation is used to evaluate its performance. Evaluations confirm structural robustness of the proposed PLL with respect to noise and distortions.
51.2. 29. Xinbo Ruan, Jiangang Wang, "Calculation of the resonant capacitor of the improved current-doubler-rectifier ZVS PWM full-bridge converter," Trans. on Industrial Electronics, vol. 51, no. 2, pp. 518- 520, April 2004. Full Text Link
Abstract: A resonant capacitor is introduced to the current-doubler-rectifier zero-voltage-switching pulsewidth-modulation full-bridge converter to alleviate the limit for the leakage inductance of the transformer. In this letter, the effect and calculation of the introduced resonant capacitor are analyzed and verified by a 540-W prototype converter.
51.3. 1. Jian-Xin Xu, S.K. Panda, Ya-Jun Pan, Tong Heng Lee, B.H. Lam, "A modular control scheme for PMSM speed control with pulsating torque minimization," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 526- 536, June 2004. Full Text Link
Abstract: In this paper, a modular control approach is applied to a permanent-magnet synchronous motor (PMSM) speed control. Based on the functioning of the individual module, the modular approach enables the powerfully intelligent and robust control modules to easily replace any existing module which does not perform well, meanwhile retaining other existing modules which are still effective. Property analysis is first conducted for the existing function modules in a conventional PMSM control system: proportional-integral (PI) speed control module, reference current-generating module, and PI current control module. Next, it is shown that the conventional PMSM controller is not able to reject the torque pulsation which is the main hurdle when PMSM is used as a high-performance servo. By virtue of the internal model, to ify the torque pulsation it is imperative to incorporate an internal model in the feed-through path. This is achieved by replacing the reference current-generating module with an iterative learning control (ILC) module. The ILC module records the cyclic torque and reference current signals over one entire cycle, and then uses those signals to update the reference current for the next cycle. As a consequence, the torque pulsation can be reduced significantly. In order to estimate the torque ripples which may exceed certain bandwidth of a torque transducer, a novel torque estimation module using a gain-shaped sliding-mode observer is further developed to facilitate the implementation of torque learning control. The proposed control system is evaluated through real-time implementation and experimental results validate the effectiveness.
51.3. 2. D. Simon, D.L. Feucht, "Synchronous motor phase control by vector addition of induced winding voltages," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 537- 544, June 2004. Full Text Link
Abstract: We propose a simple low-cost approach to the winding-sensed control of three-phase synchronous permanent-magnet motors. Our approach results from a straightforward but elegant application of vector-based motor theory. The method therefore does not depend on the differential equations that describe the motor dynamics, and it does not depend on the particular motor parameters. The single method we derive applies to both wye- and delta-configured motors. We vectorially sum the voltage waveforms at the motor terminals in a certain way and use their zero crossings to produce a correctly phased six-step switch sequence. We discuss the implementation for both wye- and delta-configured motors, and we present experimental results for a delta-configured implementation.
51.3. 3. Young Ahn Kwon, Sung Hwan Kim, "A new scheme for speed-sensorless control of induction motor," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 545- 550, June 2004. Full Text Link
Abstract: Various control algorithms have been proposed for the speed-sensorless control of an induction motor. These sensorless algorithms are mainly based on the speed feedback with the flux and speed estimations. This paper proposes a new scheme for the speed-sensorless control of an induction motor. The proposed scheme is based on the current estimation without the flux and speed estimations, in which the controlled stator voltage is applied to the induction motor so that the difference between stator currents of the mathematical model and motor may be forced to decay to zero. The performance of the proposed scheme is verified through simulation and experiment.
51.3. 4. Li Ran, Yong Liao, "Sampling-induced resonance in an encoderless vector-controlled induction motor drive," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 551- 557, June 2004. Full Text Link
Abstract: This paper illustrates an effect of sampling in an encoderless vector-controlled induction motor drive with a digital controller. The analysis focuses on the speed observer and the speed control loop which is executed at discrete instants. It is shown that the estimated speed can fluctuate between samples in the speed loop and cause a sustained resonance via feedback. The shaft inertia is not available to smooth the ripple of the estimated speed and the associated resonance could adversely affect the inverter and machine. An analytical model is proposed to evaluate the risk of such a condition in the design and on-site adjustment of control gains. The requirement for a smoothing filter in the speed loop is identified.
51.3. 5. T.W.S. Chow, Shi Hai, "Induction machine fault diagnostic analysis with wavelet technique," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 558- 565, June 2004. Full Text Link
Abstract: A wavelet transform based method was developed for diagnosing machine faults operating at different rotating speeds. This paper shows that machine fault diagnosis can be effectively performed when an appropriate narrow-band filter is used to extract the required spectra components. A wavelets-transform-based technique is used to design specified narrow filter banks. This enables effective machine fault diagnostic analysis to be performed in the frequency domain. Gaussian-enveloped oscillation-type wavelet is employed. By matching the wavelet basis functions with the associated faulty signals, the required narrow filter banks are obtained. As a result, the detection and diagnosis of machine faults operating at different rotating speeds are made possible. The proposed technique was thoroughly tested at different rotating speeds.
Power Electronics
51.3. 6. G. Moschopoulos, P.K. Jain, "A novel single-phase soft-switched rectifier with unity power factor and minimal component count," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 566- 576, June 2004. Full Text Link
Abstract: A novel, single-phase soft-switched boost AC-DC rectifier that operates with power-factor correction is proposed in this paper. The rectifier is a modified boost voltage-doubler converter well suited for low-line-input applications. It operates with fewer conduction losses and half the switch voltage stresses found in a standard boost converter. Soft switching in the converter is achieved using a zero-current-switching quasi-resonant technique. In the paper, the converter and its modes of operation are discussed and analyzed. The method of control is explained, and a design procedure is derived and then demonstrated with an example. The feasibility of the converter is shown with experimental results obtained from a prototype.
51.3. 7. Chung-Wook Roh, Seung-Hoon Han, Sung-Soo Hong, Sug-Chin Sakong, Myung-Joong Youn, "Dual-coupled inductor-fed DC/DC converter for battery drive applications," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 577- 584, June 2004. Full Text Link
Abstract: A new isolated boost DC/DC converter suitable for a low-input-voltage application is introduced. The proposed converter features low switch current stresses, wide range of input voltage, and inherent inrush current protection, essential for the design of a low-to-high-voltage conversion circuit. A comparative analysis and experimental results are presented to show the validity of the proposed converter.
51.3. 8. H. Abu-Rub, J. Guzinski, Z. Krzeminski, H.A. Toliyat, "Predictive current control of voltage-source inverters," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 585- 593, June 2004. Full Text Link
Abstract: A new predictive current controller for a voltage-source inverter is presented in this paper. Practical aspects of realizing the new controller in a system with a digital signal processor (DSP) are considered. Delays introduced by measurements are considered and an improved algorithm with one-period prediction of current is presented. The controller was realized in an experimental system with DSP and field-programmable gate array circuits. Results of the simulations and experiments are presented.
51.3. 9. Fang Lin Luo, Hong Ye, "Positive output multiple-lift push-pull switched-capacitor Luo-converters," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 594- 602, June 2004. Full Text Link
Abstract: Micro-power-consumption technique requires high-power-density dc/dc converters and power supply source. Voltage lift technique is a popular method to apply in electronic circuit design. Since a switched capacitor can be integrated into a power IC chip, its size is small. Combining switched-capacitor and voltage lift technique can construct dc/dc converters with small size, high power density, high-voltage transfer gain, high power efficiency, and low electromagnetic interference. This paper introduces a new series of dc/dc converters-positive output multiple-lift push-pull switched-capacitor dc/dc Luo-converters.
51.3. 10. R. Cardenas, R. Pena, G.M. Asher, J. Clare, R. Blasco-Gimenez, "Control strategies for power smoothing using a flywheel driven by a sensorless vector-controlled induction machine operating in a wide speed range," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 603- 614, June 2004. Full Text Link
Abstract: This paper presents a novel control strategy for power smoothing. The system is based on a sensorless vector-controlled induction machine driving a flywheel. The problem of regulating the DC-link voltage against input power surges or sudden changes in load demand is addressed. The induction machine is controlled to operate in a wide speed range by using flux weakening above rated speed. A model reference adaptive system observer is used to obtain the rotational speed in the whole speed range. The observer parameters are adapted during flux weakening in order to obtain close tracking of the flywheel speed. Experimental results for the operation of the induction machine between zero to more than twice base speed are presented and discussed.
51.3. 11. Jun-Young Lee, Jin-Sung Kim, Nam-Sung Jung, Bo-Hyung Cho, "The current injection method for AC plasma display panel (PDP) sustainer," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 615- 624, June 2004. Full Text Link
Abstract: A new concept of energy recovery for a plasma display panel (PDP) is proposed. Different from conventional LC resonant sustaining drivers, the current built up before inverting the polarity of the panel electrodes is utilized to change the panel polarity together with energy previously charged in panel capacitance. This operation provides zero-voltage switching of switches and reduction of electromagnetic interference by rejecting the surge current when the sustain switches are turned on. The buildup current helps to reduce the transition time of the panel polarity and may produce more stable light waveforms. This method is suitable for a PDP sustaining driver requiring stable light emission characteristic while it maintains low circuit loss like the series-resonant-type energy recovery circuit which is known to be a very effective method.
51.3. 12. H. Matsuo, Wenzhong Lin, F. Kurokawa, T. Shigemizu, N. Watanabe, "Characteristics of the multiple-input DC-DC converter," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 625- 631, June 2004. Full Text Link
Abstract: In the zero-emission electric power generation system, a multiple-input DC-DC converter is useful to obtain the regulated output voltage from several input power sources such as a solar array, wind generator, fuel cell, and so forth. A new multiple-input DC-DC converter is proposed and analyzed. As a result, the static and dynamic characteristics are clarified theoretically, and the results are confirmed by experiment.
51.3. 13. N.P. Papanikolaou, E.C. Tatakis, "Active voltage clamp in flyback converters operating in CCM mode under wide load variation," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 632- 640, June 2004. Full Text Link
Abstract: Active clamp topologies of low power dissipation have become a very attractive solution in order to limit overvoltages in flyback converters. Although many suitable topologies have been introduced for the case of discontinuous conduction mode (DCM), where the duty cycle value depends on the load level, in continuous conduction mode (CCM) it is more difficult to appropriately design such topologies so as to "sense" load changes-due to the small duty cycle divergence under wide load variation. Taking for granted that in order to achieve high power-factor correction in these converters, CCM is a more attractive mode of operation, a drastic solution for this case that will manage to eliminate voltage stresses under wide load changes has become very essential. For this purpose, this paper presents an active clamp topology with small power dissipation, suitable for flyback converters operating in CCM mode. Its main idea is the use of a load-dependent current source, consisting of an auxiliary converter operating in DCM mode. Experimental results highlight the effectiveness of the proposed topology under wide load changes, establishing it as an appropriate solution in order to develop flyback converters, even at the power range of 500 W.
51.3. 14. B. Singh, B.N. Singh, A. Chandra, K. Al-Haddad, A. Pandey, D.P. Kothari, "A review of three-phase improved power quality AC-DC converters," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 641- 660, June 2004. Full Text Link
Abstract: Three-phase AC-DC converters have been developed to a matured level with improved power quality in terms of power-factor correction, reduced total harmonic distortion at input AC mains, and regulated DC output in buck, boost, buck-boost, multilevel, and multipulse modes with unidirectional and bidirectional power flow. This paper presents an exhaustive review of three-phase improved power quality AC-DC converters (IPQCs) configurations, control strategies, selection of components, comparative factors, recent trends, their suitability, and selection for specific applications. It is aimed at presenting a state of the art on the IPQC technology to researchers, designers, and application engineers dealing with three-phase AC-DC converters. A classified list of around 450 research articles on IPQCs is also appended for a quick reference.
51.3. 15. A. Emadi, "Modeling and analysis of multiconverter DC power electronic systems using the generalized state-space averaging method," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 661- 668, June 2004. Full Text Link
Abstract: This paper presents a modular approach for the modeling and simulation of multiconverter DC power electronic systems based on the generalized state-space averaging method. These systems may consist of many individual converters connected together to form large and complex systems. In addition to simplifying the analysis procedure, by using the proposed method, the time step for analysis of the system can be increased. Therefore, the required computation time and computer memory for complex systems can be reduced considerably. In this paper, after introducing the proposed approach, results of applying the method to a representative system are presented.
51.3. 16. B.A. Welchko, M.B. de Rossiter Correa, T.A. Lipo, "A three-level MOSFET inverter for low-power drives," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 669- 674, June 2004. Full Text Link
Abstract: This paper proposes operating a three-level neutral-point-clamped (NPC) inverter using a two-level pulsewidth-modulation method. This allows for the clamping diodes to be rated at a fraction of the main switches due to their low average current requirement. The use of a bootstrap charge pump as a low-cost method to obtain the isolated gate drive power supplies is extended for use with the NPC topology. Using this control method and circuits, an inverter based on high-volume, low-cost, low-voltage power MOSFETs is experimentally demonstrated as a possible economic alternative to an insulated-gate-bipolar-transistor-based drive for 120-Vrms-supplied systems.
51.3. 17. Wei Wen, Kam-Wah Siu, Yim-Shu Lee, "Design of a single-switch high-power-factor regulator with near-zero output current ripple," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 675- 685, June 2004. Full Text Link
Abstract: The characteristics of a novel single-switch high-power-factor regulator with low output current ripple are studied. By employing a modified-boost converter cell as the input stage and a double-ended forward converter cell as the output stage, a high power factor and near-zero output current ripple are achieved. This regulator also eliminates the need for an extra clamping switch to recycle the transformer leakage energy and to reduce the switch voltage stress. The analysis, design, simulation, and experimental results are reported to verify the operation and performance of the proposed regulator.
Emerging Technology
51.3. 18. M.J. Embrechts, S. Benedek, "Hybrid identification of nuclear power plant transients with artificial neural networks," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 686- 693, June 2004. Full Text Link
Abstract: Proper and rapid identification of malfunctions (transients) is of premier importance for the safe operation of nuclear power plants. Feedforward neural networks trained with the backpropagation (BP) algorithm are frequently applied to model simulated nuclear power plant malfunctions. The correct identification of unlabeled transients-or transients of the "don't-know" type have proven to be especially challenging. A novel hybrid neural network methodology is presented which also correctly classifies the unlabeled transients. From this analysis the importance for properly accommodating practical aspects such as the drift of electronics elements of a simulator, the digitization of simulated and actual plant signals, and the accumulating errors during numerical integration became obvious. Beside the feedforward neural networks trained with the BP algorithm, many other types of networks and codes were used for finding the best (sensitive and robust) algorithms. Various neural network based models were successfully applied to identify labeled and unlabeled malfunctions of the Hungarian Paks nuclear power plant simulator. The BP and probabilistic methods have been proven as the most robust against the misleading recognition of unlabeled malfunctions.
51.3. 19. N. Gebraeel, M. Lawley, R. Liu, V. Parmeshwaran, "Residual life predictions from vibration-based degradation signals: a neural network approach," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 694- 700, June 2004. Full Text Link
Abstract: Maintenance of mechanical and rotational equipment often includes bearing inspection and/or replacement. Thus, it is important to identify current as well as future conditions of bearings to avoid unexpected failure. Most published research in this area is focused on diagnosing bearing faults. In contrast, this paper develops neural-network-based models for predicting bearing failures. An experimental setup is developed to perform accelerated bearing tests where vibration information is collected from a number of bearings that are run until failure. This information is then used to train neural network models on predicting bearing operating times. Vibration data from a set of validation bearings are then applied to these network models. Resulting predictions are then used to estimate the bearing failure time. These predictions are then compared with the actual lives of the validation bearings and errors are computed to evaluate the effectiveness of each model. For the best model, we find that 64% of predictions are within 10% of actual bearing life, while 92% of predictions are within 20% of the actual life.
51.3. 20. Kyung Chang Lee, Hyun Hee Kim, Suk Lee, Man Hyung Lee, "Timer selection for satisfying the maximum allowable delay using performance model of profibus token passing protocol," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 701- 710, June 2004. Full Text Link
Abstract: Recently, the Fieldbus has become an indispensable component for many automated systems. In the Fieldbus system, real-time data containing sensor values and control commands have a tendency to rapidly lose their value as time elapses after its creation. In order to deliver these data in time, the fieldbus network should be designed to have a short delay compared to the maximum allowable delay. Because the communication delay is affected by performance parameters such as the target rotation timer of token passing protocol, it is necessary to select proper parameter settings to satisfy the real-time requirement for communication delay. This paper presents the timer selection method for Profibus token passing networks using a genetic algorithm to meet the delay requirements.
Robotics And Vision
51.3. 21. Min-Jung Lee, Young-Kiu Choi, "An adaptive neurocontroller using RBFN for robot manipulators," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 711- 717, June 2004. Full Text Link
Abstract: In recent years, neural networks have fulfilled the promise of providing model-free learning controllers for nonlinear systems; however, it is very difficult to guarantee the stability and robustness of neural network control systems. This paper proposes an adaptive neurocontroller for robot manipulators based on the radial basis function network (RBFN). The RBFN is a branch of neural networks and is mathematically tractable. Therefore, we adopt the RBFN to approximate nonlinear robot dynamics. The RBFN generates control input signals based on the Lyapunov stability that is often used in the conventional control schemes. A saturation function is also chosen as an auxiliary controller to guarantee the stability and robustness of the control system under the external disturbances and modeling uncertainties.
51.3. 22. Joon Seop Oh, Yoon Ho Choi, Jin Bae Park, Y.F. Zheng, "Complete coverage navigation of cleaning robots using triangular-cell-based map," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 718- 726, June 2004. Full Text Link
Abstract: This paper presents a novel approach for navigation of cleaning robots in an unknown workspace. To do so, we propose a new map representation method as well as a complete coverage navigation method. First, we discuss a triangular cell map representation which makes the cleaning robot navigate with a shorter path and increased flexibility than a rectangular cell map representation. Then, we propose the complete coverage navigation and map construction methods which enable the cleaning robot to navigate the complete workspace without complete information about the environment. Finally, we evaluate the performance of our proposed triangular cell map via the existing distance-transform-based path-planning method comparing it to that of the rectangular cell map. Also, we verify the effectiveness of the proposed methods through computer simulations.
Letters To The Editor
51.3. 23. F. Jurado, "Neural network control for dynamic voltage restorer," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 727- 729, June 2004. Full Text Link
Abstract: The dynamic voltage restorer is a power electronic device which has demonstrated its ability to protect sensitive loads from the effects of voltage sags. This compensator is connected in series with the distribution feeder. A neural network control is proposed. Simulation results are shown to validate these control methods.
51.3. 24. Z.H. Shao, "Robust stability of uncertain neutral delay systems," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 730- 733, June 2004. Full Text Link
Abstract: The stability of a linear neutral delay-differential system is studied, where both the system matrices and time delays may be uncertain. A sufficient condition is derived to guarantee the perturbed system is robustly stable. The computation of acceptable upper bounds for system matrix uncertainties and time-delay perturbations is also discussed, and an example is finally illustrated.
51.3. 25. K.C. Wu, "A comprehensive analysis of current-mode control for DCM buck-boost converters," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 733- 735, June 2004. Full Text Link
Abstract: Comprehensive analyses for the buck-boost, pulse width modulation DC/DC converters applying peak current current-mode control are given. The analysis provides closed-form solutions for steady-state output, small-signal loop gain, and conducted susceptibility. It also proves that the state-space averaged model developed for converter using a single-loop voltage-mode control is valid for a current-mode-controlled converter.
51.3. 26. R.J. Mantz, H. De Battista, "Comments on "variable-structure PID control to prevent integrator windup"," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 736- 738, June 2004. Full Text Link
Abstract: In the paper by Hodel and Hall, the authors introduce a variable-structure proportional-integral-derivative controller with antiwindup features and compare it with other simple antiwindup methods. It is pointed out here that the conclusions reached from the comparative example are incorrect as the performance of the controllers is not appropriately compared.
51.3. 27. A.S. Hodel, C.E. Hall, "Authors' reply to comments on "variable-structure PID control to prevent integrator windup"," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 738- 739, June 2004. Full Text Link
Abstract: For comments by R.J. Mantz and H. De Battisa see ibid. (vol. 51, p736-38, June 2004) . For original paper by A. S. Hodel and C. E. Hall see ibid.(vol.48, p442-51, April 2001).
51.3. 28. L.U. Gokdere, M.A. Simaan, C.W. Brice, "Response to comments on "passivity-based control of saturated induction motors"," Trans. on Industrial Electronics, vol. 51, no. 3, pp. 739, June 2004. Full Text Link
Abstract: For original paper by L. U. Gokdere et al. see ibid.(vol.48, p870-72, Aug. 2001) Contrary to the claims made in the comments to our paper, by R. T. Novotnak and J. Chiasson see ibid.(vol.50, p820-21, Aug. 2003), the passivity-based controller developed for induction motors has already been tested on the same demanding trajectories used for the input-output linearization controller. The experimental results show that the passivity-based controller provides closer tracking of the same mechanical trajectory, when compared with the input-output linearization controller.
Special Section Papers on Direct Torque
Control of AC Motors
51.4. 1. G.S. Buja, M.P. Kazmierkowski, "Direct torque control of PWM inverter-fed AC motors - a survey," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 744- 757, Aug. 2004. Full Text Link
Abstract: This paper presents a review of recently used direct torque and flux control (DTC) techniques for voltage inverter-fed induction and permanent-magnet synchronous motors. A variety of techniques, different in concept, are described as follows: switching-table-based hysteresis DTC, direct self control, constant-switching-frequency DTC with space-vector modulation (DTC-SVM). Also, trends in the DTC-SVM techniques based on neuro-fuzzy logic controllers are presented. Some oscillograms that illustrate properties of the presented techniques are shown.
51.4. 2. N.R.N. Idris, A.H.M. Yatim, "Direct torque control of induction machines with constant switching frequency and reduced torque ripple," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 758- 767, Aug. 2004. Full Text Link
Abstract: Direct torque control (DTC) of induction machines is known to have a simple control structure with comparable performance to that of the field-oriented control technique. Two major problems that are usually associated with DTC drives are: switching frequency that varies with operating conditions and high torque ripple. To solve these problems, and at the same time retain the simple control structure of DTC, a constant switching frequency torque controller is proposed to replace the conventional hysteresis-based controller. In this paper, the modeling, averaging, and linearization of the torque loop containing the proposed controller followed by simulation and experimental results are presented. The proposed controller is shown to be capable of reducing the torque ripple and maintaining a constant switching frequency.
51.4. 3. Y.-S. Lai, Wen-Ke Wang, Yen-Chang Chen, "Novel switching techniques for reducing the speed ripple of AC drives with direct torque control," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 768- 775, Aug. 2004. Full Text Link
Abstract: The main theme of this paper is to present novel switching techniques, which insert zero-voltage vectors and/or more nonzero-voltage vectors to the conventional switching table, for AC drives with direct torque control. For the same sampling frequency of a drive controller, the proposed techniques are quite effective in reducing the torque pulsation and the speed ripples of the motors, as demonstrated in several experimental results. Moreover, the experimental confirmations have been made not only on an induction machine but also on a permanent-magnet synchronous machine.
51.4. 4. V. Ambrozic, G.S. Buja, R. Menis, "Band-constrained technique for direct torque control of induction motor," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 776- 784, Aug. 2004. Full Text Link
Abstract: In this paper, a novel technique for the direct torque control (DTC) of an induction motor is proposed, which overcomes the trouble of high torque ripple afflicting the conventional DTC technique. With the novel technique, the inverter voltage vector selected from the switching table is applied for the time interval needed by the torque to reach the upper (or the lower) limit of the band, where the time interval is calculated from a suitable modeling of the torque dynamics. By this approach, the control system emulates the operation of a torque hysteresis controller of analog type since the application time of the inverter voltage vector is dictated by the allowed torque excursion and not by the sampling period. It is shown by experimental results that the technique yields a considerable reduction of the torque ripple. A further and ultimate reduction is obtained by compensating for the delay inherent in the discrete-time operation of the control system. The outcome is that the torque ripple of the motor is constrained within the hysteresis band of the torque controller, for a band of customary value. An ancillary merit of the technique is the almost full elimination of the average torque error inherent in the conventional technique. If the hysteresis band is shrunk, the torque ripple is bound to swing out the band limits. Under this circumstance, an extension of the technique is developed, which helps keep the torque ripple at minimum. To assess the characteristics of the proposed DTC technique, the following quantities: average torque error, rms value of the torque ripple, and inverter switching frequency are measured for different stator flux angular speeds and hysteresis bands of the torque and flux controllers. As a comparison, the same quantities are given for the conventional DTC technique.
51.4. 5. C. Lascu, I. Boldea, F. Blaabjerg, "Variable-structure direct torque control - a class of fast and robust controllers for induction machine drives," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 785- 792, Aug. 2004. Full Text Link
Abstract: A family of variable-structure controllers for induction machine drives is presented, in which the principles of direct torque control (DTC), variable-structure control (VSC), and space-vector pulsewidth modulation are combined to ensure high-performance operation, both in the steady state and under transient conditions. Three new VSC schemes are designed following the DTC voltage-control-based philosophy. These provide robust, fast, and accurate torque and flux control, without the penalty of high chattering. Comparative results demonstrate that proposed techniques preserve the DTC transient merits, while the steady-state behavior is significantly improved. Experimental results prove the strong robustness, accuracy, quickness, and low-ripple sensor-less operation of a drive that uses the new schemes.
51.4. 6. J. Luukko, O. Pyrhonen, M. Niemela, J. Pyrhonen, "Limitation of the load angle in a direct-torque-controlled synchronous machine drive," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 793- 798, Aug. 2004. Full Text Link
Abstract: The basic direct torque control (DTC) principle is to rotate the flux linkage forward, if the torque must be increased, and reverse, if the torque must be decreased. The torque is, however, increased only up to a maximum torque of the machine, which corresponds to a load angle of about 90/spl deg/ in a synchronous machine. This paper presents a method to overcome the possible loss of synchronism when using DTC. This requires either that the rotor angle is measured or estimated. Both of these cases are considered. Simulation and laboratory results are presented to show the effectiveness of the presented method.
51.4. 7. M.F. Rahman, Md.E. Haque, Lixin Tang, Limin Zhong, "Problems associated with the direct torque control of an interior permanent-magnet synchronous motor drive and their remedies," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 799- 809, Aug. 2004. Full Text Link
Abstract: This paper investigates problems associated with the implementation of a direct torque control (DTC) strategy for an interior permanent-magnet synchronous motor drive. The DTC technique is increasingly drawing attention because of elimination of current controllers and, hence, their inherent delays, and elimination of the rotor position sensor. The latter advantage perhaps is the main impetus for considering this new approach of torque control. Problems associated with this controller, namely, the offset in the current measurements, the stator resistance variation, and the requirement of initial rotor position are addressed in this paper. Ways of mitigating of these problems are also investigated in this paper. These are evaluated with modeling and experimental studies, results of which are also presented.
51.4. 8. A. Steimel, "Direct self-control and synchronous pulse techniques for high-power traction inverters in comparison," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 810- 820, Aug. 2004. Full Text Link
Abstract: High-power inverters for traction drives employ in the upper range of stator frequency special pulse control methods, optimized synchronous pulsewidth modulation (PWM), mainly in combination with rotor-flux-oriented control schemes, and direct self-control (DSC) which encompasses motor control and pulse pattern generation. The well-known symmetrized sinusoidal PWM is only to be used in the lower speed range. This paper presents and compares exemplarily the stationary behavior of these two control methods; criteria are inverter peak current, motor harmonic losses, torque ripple, and DC-link harmonics. For these low switching frequencies DSC shows, in spite of its simplicity, a very good overall performance, mainly by avoiding the imperfect use of switching frequency by the synchronous pulse patterns.
51.4. 9. K. Yoshida, H. Takami, A. Fujii, "Smooth section crossing of controlled-repulsive PM LSM vehicle by DTC method based on new concept of fictitious section," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 821- 826, Aug. 2004. Full Text Link
Abstract: This paper presents propulsion control for the permanent-magnet linear synchronous motor vehicle Marine-Express 03 (ME03) to pass through the two sections in the mass-reduced mode by a new direct torque control (DTC) method. A fictitious section is introduced for pass-through-section control. It has been done by introducing a fictitious section defined by "one section including section boundary." The lift and thrust forces for the pass-through section are obtained by the DTC method based on voltage equations per one fictitious section. The vehicle ME03 has been controlled successfully to pass through the two sections in the mass-reduced mode by experiment.
51.4. 10. J. Rodriguez, J. Pontt, S. Kouro, P. Correa, "Direct torque control with imposed switching frequency in an 11-level cascaded inverter," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 827- 833, Aug. 2004. Full Text Link
Abstract: This paper presents the application of direct torque control in an induction motor, using a multilevel cascaded inverter with separated DC sources. The control strategy operates with imposed switching frequency, improving torque behavior. The paper studies the theoretical concepts related to this method, like vector selection, state variables estimation, and commutation time calculation. In addition, this paper presents results for a three- and eleven-level inverter-fed drives, from which it can be appreciated that the increase of levels of the load voltage reduces the torque ripple.
Power Electronics
51.4. 11. J. Rodriguez, J. Pontt, P. Correa, P. Cortes, C. Silva, "A new modulation method to reduce common-mode voltages in multilevel inverters," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 834- 839, Aug. 2004. Full Text Link
Abstract: This paper proposes a new modulation strategy for multilevel inverters, which selects voltage vectors that generate zero common-mode voltage in the load, working at low switching frequency. Experimental results confirm that the method is highly effective and simple to implement in a modern microprocessor. The voltage distortion (total harmonic distortion), the number of commutations, and the linearity are also studied. Finally, it is concluded that the proposed strategy is highly suited for inverters with a high number of levels.
51.4. 12. M.D.L. del Casale, N. Femia, P. Lamberti, V. Mainardi, "Selection of optimal closed-loop controllers for DC-DC voltage regulators based on nominal and tolerance design," Trans. on Industrial Electronics, vol. 51, no. 4, pp. 840- 849, Aug. 2004. Full Text Link
Abstract: This paper discusses a tolerance design approach for the feedback compensation networks of DC/DC switching regulators, identifying the most reliable solutions among different feasible alternatives that fulfil closed-loop design constraints. A voltage-mode-regulated DC/DC buck converter is considered as a case study. Given the performance and stability constraints, as tolerance ranges for crossover frequency and phase margin, feasible design solutions are sought by means of Monte Carlo and interval arithmetic computations. The search space is a set of available commercial values of RC parameters and related tolerances. Best design is identified by a weighted fitness function, exploring the set of solutions provided by different design approaches. The results presented in the paper highlight that the tolerance design approach allows one to find compensation networks that fit the given performance/robustness priorities better than those ones found by means of the classical nominal design approach.
51.4. 13. J. Diaz, F. Nuno, J.M. Lopera, J.A. Martin-Ramos, "A new control strategy for an AC/DC converter based on a piezoelectric transformer
IEEE Transactions on Industrial Electronics
