Special Section Papers on Modern
Rectifiers - Part 1
1. J.R. Rodriguez, J.W. Dixon, J.R. Espinoza, J. Pontt, P. Lezana, "PWM regenerative rectifiers: state of the art," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 5- 22, Feb. 2005. Full Text Link Abstract : New regulations impose more stringent limits on current harmonics injected by power converters that are achieved with pulsewidth-modulated (PWM) rectifiers. In addition, several applications demand the capability of power regeneration to the power supply. This work presents the state of the art in the field of regenerative rectifiers with reduced input harmonics and improved power factor. Regenerative rectifiers are able to deliver energy back from the dc side to the ac power supply. Topologies for single- and three-phase power supplies are considered with their corresponding control strategies. Special attention is given to the application of voltage- and current-source PWM rectifiers in different processes with a power range from a few kilowatts up to several megawatts. This paper shows that PWM regenerative rectifiers are a highly developed and mature technology with a wide industrial acceptance.
2. G. Moschopoulos, P. Jain, "Single-phase single-stage power-factor-corrected converter topologies," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 23- 35, Feb. 2005. Full Text Link Abstract : Single-phase single-stage power-factor-corrected converter topologies are reviewed in this paper. The topologies discussed in the paper are related to ac-dc and ac-ac converters that are classified on the basis of the frequency of the input ac source, the presence of a dc-link capacitor, and the type of control used (resonant or pulsewidth modulation). The general operating principles and strengths and weaknesses of the converters, which the authors have investigated over the last decade, are discussed in detail, and their suitability in practical applications is stated. Considering practical design constraints, it is possible to effectively employ many single-stage converter topologies in a wide range of applications.
3. J.-C. Crebier, B. Revol, J.P. Ferrieux, "Boost-chopper-derived PFC rectifiers: interest and reality," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 36- 45, Feb. 2005. Full Text Link Abstract : This work presents an overview of single-phase boost-chopper-derived power-factor-correction rectifiers. Converters are presented for several control strategies in continuous and discontinuous current mode operations. The presentation highlights the main characteristics of the converters and underlines harmonic content over a wide frequency range. A methodology is derived to compute these harmonics in order to facilitate the analysis and performance evaluation of the converters. Based on this methodology, a comparison is conducted in order to highlight advantages and drawbacks of the most popular converters and control strategies. A table is given where main converter critical parameters are summarized in order to help the designer, in converter and operating mode selections. Practical results are provided to validate the modeling technique.
4. A. Fernandez, J. Sebastian, M.M. Hernando, P. Villegas, J. Garcia, "Helpful hints to select a power-factor-correction solution for low- and medium-power single-phase power supplies," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 46- 55, Feb. 2005. Full Text Link Abstract : This work presents a review of power-factor-correction (PFC) circuits for low- and medium-power single-phase power supplies. The main idea is not just to show the state of the art of this topic but to select the most interesting topologies for each application depending on the power level, the input voltage range, and the output voltage. Since IEC 61000-3-2 regulations came into force, many new topologies have been presented trying to obtain a cost-effective solution to reduce the input current harmonic content. Each one of them has its application range due to the inherent characteristics of the topology. Obviously, not every converter is useful for the same application. This is especially perceptible in PFC circuits due to the large amount of different solutions. Hence, this paper tries to show the most appropriate topologies for each application, being the input power and the IEC 61000-3-2 Class some of the main parameters to select it. The scope of the paper is focused on single-phase power supplies belonging to IEC 61000-3-2 Class A and Class D with an input power level below 4 kW.
5. F.J. Azcondo, C. Branas, R. Casanueva, S. Bracho, "Power-mode-controlled power-factor corrector for electronic ballast," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 56- 65, Feb. 2005. Full Text Link Abstract : Medium- to high-power electronic ballasts are designed with two power conversion stages. The power-factor corrector (PFC) stabilizes the voltage supplied to the second stage and forces the utility current to meet the required standard. The inverter section stabilizes the arc in the lamp, and keeps the lamp power under the specified values. This paper proposes that the PFC section is to provide the power stability of the system while the inverter section operates in open loop. Consequences of this solution are: the power variation in the lamp caused by its aging is prevented, the complex dynamic of the lamp has no influence in the design, some extra voltage is available to achieve the lamp ignition, warmup time is reduced, and dimming control is easily implemented by modifying either the power reference or the bias value in the PFC control circuit. The inverter section is a half-bridge LC/sub p/C/sub s/ resonant inverter designed to require minimum variation of the input voltage to supply constant power to the lamp. In this way the operation point suffers little changes and no overdimensioning of the PFC and inverter components is necessary to meet the power source condition.
6. E. Figueres, J.-M. Benavent, G. Garcera, M. Pascual, "Robust control of power-factor-correction rectifiers with fast dynamic response," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 66- 76, Feb. 2005. Full Text Link Abstract : This paper proposes a new robust control technique for single-phase boost high-power-factor rectifiers. The proposed circuit significantly improves the dynamic response of the converter to load steps without the need of a high crossover frequency of the voltage loop, so that a low distortion of the input current is easily achieved. A 250-W power-factor-correction rectifier with the proposed control scheme has been designed and implemented, validating the concept both analytically and experimentally.
7. A. Fernandez, J. Sebastian, P. Villegas, M.M. Hernando, D.G. Lamar, "Dynamic limits of a power-factor preregulator," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 77- 87, Feb. 2005. Full Text Link Abstract : Power-factor correction has been one of the hottest topics during the last few years and, hence, many new circuits have appeared. In general, it is assumed that preregulators based on multiplier circuits have poor dynamics and, then, a second stage is needed to improve the output voltage dynamic behavior. The other option is the use of single-stage topologies which have fast output voltage regulation although the input current waveform is not sinusoidal. This work presents an analysis of the dynamic behavior of a conventional power-factor preregulator. The objective is to find the limits of the dynamic characteristics of these circuits when the priority is to improve the output voltage regulation and not the total harmonic distortion or the power factor. A large-signal model is presented and the theoretical results are validated with a prototype.
8. Koen De Gusseme, D.M. Van de Sype, A.P.M. Van den Bossche, J.A. Melkebeek, "Digitally controlled boost power-factor-correction converters operating in both continuous and discontinuous conduction mode," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 88- 97, Feb. 2005. Full Text Link Abstract : Whereas power-factor-correction (PFC) converters for low-power ranges (less than 250 W) are commonly designed for operation in the discontinuous conduction mode, converters for higher power levels are operated in the continuous conduction mode. Nevertheless, when these converters are operated at reduced power, discontinuous conduction mode will appear during parts of the line period, yielding input current distortion. This distortion can be eliminated by employing a dedicated control algorithm, consisting of sample correction and duty-ratio feedforward. The reduction of the harmonic distortion of the input current and the increase of the power factor are demonstrated by experiments on a 1-kW boost PFC converter.
9. Z.Z. Ye, M.M. Jovanovic, "Implementation and performance evaluation of DSP-based control for constant-frequency discontinuous-conduction-mode boost PFC front end," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 98- 107, Feb. 2005. Full Text Link Abstract : A digital signal processor (DSP) implementation of digital control for constant-frequency, discontinuous-conduction-mode boost power-factor-correction converter for universal line-voltage (90-264 V/sub rms/) applications is presented. A step-by-step design procedure based on digital redesign technique is also provided. The performance evaluation of the proposed DSP control is performed on a 400-W prototype. It was shown that the implemented DSP-based control can achieve a power factor higher than 0.99 in the entire line range.
10. D.M. Van de Sype, Koen De Gusseme, A.P.M. Van den Bossche, J.A. Melkebeek, "Duty-ratio feedforward for digitally controlled boost PFC converters," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 108- 115, Feb. 2005. Full Text Link Abstract : When a "classical" current control scheme is applied, the line current of a boost power-factor-correction (PFC) converter leads the line voltage, resulting in a nonunity fundamental displacement power factor and in important zero-crossing distortion in applications with a high line frequency (e.g., 400-Hz power systems on commercial aircraft). To resolve this problem, a current-control scheme is proposed using duty-ratio feedforward. In this paper, the input impedance of the boost PFC converter for both the classical current-loop controller and the controller using duty-ratio feedforward are derived theoretically. A comparison reveals the advantages of the proposed control scheme: a low total harmonic distortion of the line current, a resistive input impedance, virtually no zero-crossing distortion, and a fundamental displacement power factor close to unity. The theoretical results obtained are verified using an experimental setup of a digitally controlled boost PFC converter.
11. M. Ferdowsi, A. Emadi, "Pulse regulation control technique for integrated high-quality rectifier-regulators," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 116- 124, Feb. 2005. Full Text Link Abstract : The pulse regulation control scheme is presented and applied to the boost integrated flyback rectifier/energy storage dc/dc (BIFRED) converter as the most popular member of the integrated high-quality rectifier-regulators (IHQRR). In contrast to the conventional control techniques, the principal idea of pulse regulation is to regulate the output voltage using a series of high- and low-power pulses generated by the current of the input inductor, which is operating in discontinuous conduction mode (DCM). Analysis of the BIFRED converter operating in DCM is presented. Fundamentals of pulse regulation as well as its stability analysis and the estimation of the output voltage ripple are introduced. Experimental results on a prototype converter are also presented to validate the analytical and simulation results.
12. Lon-Kou Chang, Hsing-Fu Liu, "A novel forward AC/DC converter with input current shaping and fast output voltage regulation via reset winding," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 125- 131, Feb. 2005. Full Text Link Abstract : This work presents a novel simple forward AC/DC converter with harmonic current correction and fast output voltage regulation. In the proposed AC/DC converter, a transformer incorporating reset winding provides two main advantages. First, the bulk inductor used in the conventional boost-based power-factor-correction cell is omitted in the proposed converter, allowing significant volume and weight of magnetic material to be saved. Second, the voltage across the bulk capacitor can be held under 450 V by adjusting the transformer winding ratio, despite the converter operating in a wide range of input voltages (90/spl sim/265 V/AC). This new converter complies with IEC 61000-3-2 under a load range of 200 W and has fast output voltage regulation.
13. N. Vazquez, J. Lopez, J. Arau, C. Hernandez, E. Rodriguez, "A different approach to implement an active input current shaper," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 132- 138, Feb. 2005. Full Text Link Abstract : In recent years, several AC/DC converters have been presented in order to meet the power quality regulations, while maintaining the lowest number of components with the purpose of minimizing the cost and complexity; for this purpose the active input current shaping technique was proposed. A new active input current shaper (AICS) is presented. Differently from the traditional series AICS, the proposed scheme connects the auxiliary output of the main converter in parallel with the rectified AC mains instead of the series connection. The proposed parallel scheme demands a current with a low harmonic content where the standard specifications are fulfilled. The operation, simulation, and experimental results of the proposed scheme are presented.
14. Tsai-Fu Wu, Jin-Chyuan Hung, Sheng-Yu Tseng, Yaow-Ming Chen, "A single-stage fast regulator with PFC based on an asymmetrical half-bridge topology," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 139- 150, Feb. 2005. Full Text Link Abstract : This work presents single-stage regulators with power-factor correction (PFC) based on an asymmetrical half-bridge topology. The proposed regulator is formed from a boost converter with two coupled inductors and an asymmetrical half-bridge converter with the synchronous switch technique, and it is controlled with pulsewidth modulation to achieve zero-voltage switching (ZVS). The boost converter is operated in discontinues conduction mode to achieve PFC. With the coupled inductors, input current ripple and power factor can be improved significantly. The proposed regulator has the features of constant-frequency operation, ZVS, and low voltage stress imposed on the active switches. Moreover, the regulator can achieve high power factor, high power density, high efficiency, low switching loss, and low component count, which makes its applications at medium-power levels feasible. Experimental results have verified the discussed features of the proposed regulator.
15. F. Forest, T.A. Meynard, S. Faucher, F. Richardeau, J.-J. Huselstein, C. Joubert, "Using the multilevel imbricated cells topologies in the design of low-power power-factor-corrector converters," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 151- 161, Feb. 2005. Full Text Link Abstract : Power-factor-corrector (PFC) converters are now commonly used in low-power supply systems connected to AC networks. In addition to their basic PFC properties, they constitute the best technical solution to directly obtain the compatibility with a large range of AC voltages provided by different distribution networks around the world (typically, from 85 to 265 V rms). It is the main application of these converters. This function is achieved with an additional cost and volume, and this extra price to pay needs to be minimized. In this context, we first recall the main approaches of the design of conventional PFCs based on the boost converter topology. We emphasize the different critical points of the sizing that mainly concern the input choke and the silicon devices, in regard with the choice of the switching frequency. Few ways of improvement are then presented for these conventional PFCs. In a second part, always in the context of a large input voltage range, we consider the possibility to introduce the multi-level concept to reduce the input choke and filters. A solution using a multi-level flying capacitor two-cell converter is presented. It is shown that it can lead to a significant increase of the performances, with several options of sizing which can be suited to different requirements of the applications.
16. J. Minibock, J.W. Kolar, "Novel concept for mains voltage proportional input current shaping of a VIENNA rectifier eliminating controller multipliers," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 162- 170, Feb. 2005. Full Text Link Abstract : This paper proposes a novel mains voltage proportional input current control concept eliminating the multiplication of the output voltage controller output and the mains ac phase voltages for the derivation of mains phase current reference values of a three-phase/level/switch pulsewidth-modulated (VIENNA) rectifier system. Furthermore, the concept features low input current ripple amplitude as, e.g., achieved for space-vector modulation, a low amplitude of the third harmonic of the current flowing into the output voltage center point, and a wide range of modulation. The practical realization of the analog control concept as well as experimental results for application with a 5-kW prototype of the pulsewidth-modulated rectifier are presented. Furthermore, a control scheme which relies only on the absolute values of the input phase currents and a modified control scheme which does not require information about the mains phase voltages are presented.
17. M.A. Perez, J.R. Espinoza, J.R. Rodriguez, P. Lezana, "Regenerative medium-voltage AC drive based on a multicell arrangement with reduced energy storage requirements," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 171- 180, Feb. 2005. Full Text Link Abstract : Multicell power circuit topologies have proved to be an effective alternative to medium-voltage ac drives. The main advantage is the improved power quality at both the ac system and the motor sides. However, several drawbacks are present in these configurations, such as a lack of sustained regenerative operating mode, uncontrolled input reactive power, and a large second current harmonic that is injected by the load into the dc link of each cell, which leads to a bulky electrolytic capacitor. This paper proposes to replace the input diode-based front-end rectifier with an active front-end rectifier in all cells of the topology and a novel control strategy in order to overcome the aforementioned drawbacks. In fact, the active front-end rectifier allows the topology to regenerate and the control strategy handles the reactive input power and reduces the large second current harmonic from the dc-link capacitor, thus reducing its size. These features are achieved without any penalties in the quality of both the ac input current and the motor voltage waveforms. Experimental results confirm the theoretical considerations.
18. In-Dong Kim, Eui-Cheol Nho, "Module-type switching rectifier for cathodic protection of underground and maritime metallic structures," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 181- 189, Feb. 2005. Full Text Link Abstract : Cathodic protection is widely used to prevent corrosion of steel materials buried underground and in seawater. As a rectifier for cathodic protection, the conventional phase-controlled rectifiers with 50- or 60-Hz isolation transformers have been used so far in spite of such shortcomings as large volume, heavy weight, and poor power factor. In order to overcome such disadvantages, this paper proposes a new module-type switching rectifier for cathodic protection, which is composed of two parts, namely, ac/dc converter and module-type dc/dc converter. The ac/dc converter is a single-phase insulated gate bipolar transistor pulsewidth-modulation rectifier, thus resulting in almost unity power factor and controlled dc output voltage. The module-type dc/dc converter operates under zero-voltage switching/zero-current switching condition to permit high-frequency switching operation. It enables the use of a high-frequency transformer for electrical isolation, thus reducing volume and weight of the overall system and improving system efficiency. It is anticipated that the proposed rectifier techniques will apply to the similar technical areas such as multiple-module power supply systems and modular converter-fed dc motor drives.
Power Electronics
19. J. Pou, R. Pindado, D. Boroyevich, "Voltage-balance limits in four-level diode-clamped converters with passive front ends," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 190- 196, Feb. 2005. Full Text Link Abstract : Multilevel diode-clamped converters with more than three levels cannot maintain voltage balance in the dc-link capacitors for some operating conditions due to the existence of dc currents in the middle points. Since capacitors are either completely charged or discharged for those conditions, this circumstance severely limits practical application of these converters. The limit explored in this paper is that the four-level converter cannot achieve voltage balance. Proper redundant vectors are selected in the space-vector diagram so that a quadratic parameter related to the currents in the middle points is minimized.
20. L. Yacoubi, K. Al-Haddad, F. Fnaiech, L.-A. Dessaint, "A DSP-based implementation of a new nonlinear control for a three-phase neutral point clamped boost rectifier prototype," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 197- 205, Feb. 2005. Full Text Link Abstract : This work presents the design and implementation of a nonlinear control strategy for a three-phase three-level neutral-point-clamped boost rectifier. The adopted control consists of nonlinear feedback linearization technique. The nonlinear state-space model of the rectifier was obtained in the dq0 reference frame. The input/output feedback linearization is then applied and the linearizing control law is derived. Therefore, the resulting model is linearized and decoupled in three independent subsystems. Afterwards, the stabilizing controllers are designed based on linear techniques to control line currents, output, and neutral point voltages. The control law is designed using Simulink/Matlab and applied to the converter via a 1.8-kHz pulsewidth modulator (PWM). Both control law and PWM signals are executed in real time using the DS1104 DSP of dSPACE. A 1.2 kW laboratory prototype is built for validation purposes. The proposed control law robustness is validated for diverse severe load and system parameter variations. It shows robust performance in terms of high power factor, low total harmonic distortion and output voltage ripples, small overshoot, and short settling time.
21. P. Mattavelli, "An improved deadbeat control for UPS using disturbance observers," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 206- 212, Feb. 2005. Full Text Link Abstract : A digital control technique for the inverter stage of uninterruptible power supplies is proposed, which is based on a predictive regulator on both output voltage and inductor current. Its aim is to achieve a deadbeat dynamic response for the controlled variables (output voltage and inverter current). Besides the linear state feedback which allocates system poles at the origin so as to achieve deadbeat response for all state variables, the use of a disturbance observer for the estimation of the load current and of any other source of errors (such as dead-times, parameter, and model mismatches) is investigated. The proposed solution is able to guarantee a fast dynamic response and also a precise compensation of any source of unpredictable disturbance. Moreover, with a proper design of observer parameters, it is possible to reduce control sensitivity to model uncertainties, parameter mismatches, and noise on sensed variables, which usually characterizes existing deadbeat control techniques. Finally, the control algorithm is quite simple and requires only the measurements of the output voltage and inductor current. Experimental results on a single-phase 2 kVA prototype show the effectiveness of the proposed approach.
22. Xinbo Ruan, Bin Li, "Zero-voltage and zero-current-switching PWM hybrid full-bridge three-level converter," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 213- 220, Feb. 2005. Full Text Link Abstract : This paper proposes a zero-voltage and zero-current-switching pulsewidth modulation hybrid full-bridge three-level (ZVZCS PWM H-FB TL) converter, which has a TL leg and a two-level leg. The voltage stress of the switches of the TL leg is half of the input voltage, and the switches can realize ZVS, so MOSFETs can be adopted; the voltage stress of the switches of the two-level leg is the input voltage, and the switches can realize ZCS, so IGBT can be adopted. The secondary rectified voltage is a TL waveform having lower high-frequency content compared with that of the traditional FB converters, which leads to the reduction of the output filter inductance. The input current of the converter has quite little ripple, so the input filter can also be significantly reduced. The operation principle of the proposed converter is analyzed and verified by the experimental results. Several ZVZCS PWM H-FB TL converters are also proposed in this paper.
23. L.H.S.C. Barreto, M.G. Sebastiao, L.C. de Freitas, E.A.A. Coelho, V.J. Farias, J.B. Vieira, "Analysis of a soft-switched PFC boost converter using analog and digital control circuits," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 221- 227, Feb. 2005. Full Text Link Abstract : This work presents a comparison between analog and digital (PIC16c73a) control types applied to the boost converter with a nondissipative snubber. Both control types use the bang-bang hysteresis current waveshaping control technique in order to achieve a quasi-unity power factor. The analog control applied presented a high power factor (0.998), high efficiency (92.87%), and low harmonic distortion [total harmonic distortion of current (THDI =2.84% and total harmonic distortion of current (THDV) =2.83%]. The digital control presented a high power factor (0.990), high efficiency (92.46%), and low harmonic distortion (THDI=5.09% and THDV=2.84%).
24. Gwan-Bon Koo, Gun-Woo Moon, Myung-Joong Youn, "New zero-voltage-switching phase-shift full-bridge converter with low conduction losses," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 228- 235, Feb. 2005. Full Text Link Abstract : A new zero-voltage-switching (ZVS) phase-shift full-bridge (PSFB) converter with low conduction losses is proposed. It is based on the PSFB converter with series-connected two transformers, which features wide ZVS ranges. By adding a capacitor, the proposed converter overcomes the disadvantage of the based converter, such as the high circulating energy. Furthermore, the turns ratio of the transformers can be increased as well. Therefore, high efficiency of the proposed converter can be achieved. Operational principles and experimental results for a 100-W (5 V, 20 A) prototype are presented to validate the proposed converter.
25. E. Dallago, G. De Leo, G. Sassone, "A current-mode power sigma-delta modulator for audio applications," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 236- 242, Feb. 2005. Full Text Link Abstract : Linear and switching techniques are currently adopted to implement current-mode power stages. Pulsewidth modulation (PWM) is usually employed with the switching technique for both industrial and audio applications. In this paper, the Sigma-Delta modulation is considered as an alternative to the PWM in devising a switching current-mode power stage suitable for audio amplification. The proposed modulator is analyzed and simulated. The whole system was realized on an experimental breadboard. The results carried out on the prototype are reported and discussed. The electrical characterization presents interesting features in terms of linearity, noise, and power efficiency.
26. P. Poulichet, F. Costa, E. Laboure, "A new high-current large-bandwidth DC active current probe for power electronics measurements," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 243- 254, Feb. 2005. Full Text Link Abstract : This paper is focused on the design and the realization of two high-current probes (up to 100 A) whose bandwidths range from dc to 50 MHz. The performance has been met by the association of an active Hall sensor and a passive current transformer. This association will be named an "active current transformer". It will be shown that it has better frequency performance than the classical closed-loop current transducer, usually used for high-current measurements but frequency limited. The electromagnetic interference (EMI) issues, due to the sensor electrical environment are respected thanks to the shielded structure and special inner arrangements of the Hall sensors. Because of its large bandwidth, its large current range, and its EMI ruggedness, this current probe is well matched to power electronics measurements.
Drives Control
27. O. Wallmark, L. Harnefors, O. Carlson, "An improved speed and position estimator for salient permanent-magnet synchronous motors," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 255- 262, Feb. 2005. Full Text Link Abstract : An improved phase-locked-loop-type speed and position estimator for permanent-magnet synchronous motor (PMSM) drives is considered. Particular attention is put on salient-rotor PMSMs with fast mechanical dynamics. A method is presented, whereby significantly improved tracking is achieved. While saliency makes nominal-speed stability more difficult to guarantee (an analysis of this is presented), a benefit is that signal-injection methods can be used at low speeds for accurate position estimation, which is also included in the modified estimator.
28. H. Rehman, "Elimination of the stator resistance sensitivity and voltage sensor requirement problems for DFO control of an induction Machine," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 263- 269, Feb. 2005. Full Text Link Abstract : This paper focuses on a method for achieving robust direct field orientation control of an induction machine using a closed-loop voltage model flux observer that is insensitive to stator resistance variation and does not require voltage signal information, thereby eliminating the need for a voltage sensor. In contrast, the conventional voltage model observer topology requires voltage sensors and is highly sensitive to stator resistance variation, especially at low speed. The closed-loop sliding-mode voltage model flux observer presented here is based on current estimation error including a sliding-mode function which is a derivative of the stator flux. The newly designed sliding-mode function will not only drive the estimated current to the measured one, it will also directly give the estimation results for the terms (stator flux) replaced by the sliding-mode function. The constructed observer and chosen sliding-mode function also do not require information about parameters contained in the terms replaced by the sliding-mode function, i.e., voltage signal and stator resistance. The observer stability is verified in the paper. Simulation and experimental results are also used to illustrate features of the proposed observer.
29. Kwangjin Yang, Youngjin Choi, Wan Kyun Chung, "On the tracking performance improvement of optical disk drive servo systems using error-based disturbance observer," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 270- 279, Feb. 2005. Full Text Link Abstract : There are many control methods to guarantee the robustness of a system. Among them, the disturbance observer (DOB) has been widely used because it is easy to apply and the cost is low due to its simplicity. Generally, an output signal of the system is required to construct a DOB, but for some systems such as magnetic/optical disk drive systems, we cannot measure the position output signal, but only the position error signal (PES). In order to apply a DOB to such systems, we must use an error signal instead of an output signal. We call it the error-based disturbance observer (EDOB) system. We analyze the differences between a conventional DOB system and EDOB system, and show the effectiveness of the proposed EDOB through simulations and experiments. Also, this paper proposes criteria to enhance the robustness of an EDOB system, and reveals the disturbance rejection property of the EDOB system. Finally, we propose a new method of a double Q system to improve the track-following performance. This is also verified through experiments for a DVD 12/spl times/ optical disk drive system.
Emerging Technology
30. D. Villacci, G. Bontempi, A. Vaccaro, M. Birattari, "The role of learning methods in the dynamic assessment of power components loading capability," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 280- 290, Feb. 2005. Full Text Link Abstract : The need for dynamic loading of power components in the deregulated electricity market demands reliable assessment models that should be able to predict the thermal behavior when the load exceeds the nameplate value. When assessing network load capability, the hot-spot temperature of the components is known to be the most critical factor. The knowledge of the evolution of the hot-spot temperature during overload conditions is essential to evaluate the loss of insulation life and to evaluate the consequent risks of both technical and economical nature. This paper discusses an innovative grey-box architecture for integrating physical knowledge modeling (a.k.a. white-box) with machine learning techniques (a.k.a. black-box). In particular, we focus on the problem of forecasting the hot-spot temperature of a mineral-oil-immersed transformer. We perform a set of experiments and we compare the predictions obtained by the grey-, white-, and black-box approaches.
31. Kuan-Hung Chen, Tzi-Dar Chiueh, Shi-Chung Chang, P.B. Luh, "A 1600-MIPS parallel processor IC for job-shop scheduling," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 291- 299, Feb. 2005. Full Text Link Abstract : A job shop is a typical environment for manufacturing low-volume and high-variety discrete parts, where parts are of various due dates, priorities, and sequences of production operations. Good scheduling of when to do what using which resource is critical and challenging for the competitiveness of job shops. The Lagrangian relaxation neural network (LRNN) presented by Luh et al. provides an effective solution to this problem. To further speed up the scheduling of large problems, the parallelism of the LRNN approach is exploited in this paper for hardware implementation. A parallel processor based on the single-instruction multiple-data-stream architecture and its associated instruction set are designed. The architecture is implemented in a single-poly quadruple-metal 0.35-/spl mu/m CMOS technology. Test results shows that the fabricated chip achieves 10 and 30 times speed-up when compared with several commercial digital signal processor chips and a 600-MHz PC, respectively.
32. M. Iwasaki, M. Miwa, N. Matsui, "GA-based evolutionary identification algorithm for unknown structured mechatronic systems," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 300- 305, Feb. 2005. Full Text Link Abstract : Soft computing techniques, e.g., neural networks, fuzzy inference, evolutionary computation, and chaos theory, have been applied to a wide variety of control systems in industry because of their control capability and flexibility. They are also powerful to handle the complicated mechatronic systems with various nonlinearities which are difficult to model using mathematical formulas. In order to achieve the system identification of unknown structured mechatronic systems, This work presents a novel evolutionary algorithm using genetic algorithms (GAs), where the optimal mathematical structure of plant mechanisms and the combination of parameters can be autonomously determined by means of the optimization ability of the GA. The effectiveness of the proposed identification has been verified by experiments with comparative studies, using the typical mechanical systems with velocity controller.
Robotics And Vision
33. M.A. Al-Mouhamed, O. Toker, A. Al-Harthy, "A 3-D vision-based man-machine interface for hand-controlled telerobot," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 306- 319, Feb. 2005. Full Text Link Abstract : This work presents a robust telerobotic system that consists of a real-time vision-based operator hand tracking system (client) and a slave robot (server) which are interconnected through a LAN. The tracking system: 1) monitors the operator hand motion and 2) determines its position and orientation which are used to control the slave robot. Two digital cameras are used to monitor a four-ball-based feature frame that is held by the operator hand. To determine the three-dimensional (3-D) position a tracking algorithm based on uncalibrated cameras with weak perspective projection model is used. This allows finding 3-D differential position and orientation of the operator hand. The features of the proposed system are: 1) a metric for color matching to discriminate the balls from their background; 2) a uniform and spiral search approach to speed up the detection; 3) tracking in the presence of partial occlusion; 4) consolidate detection by using shape and geometric matching; and 5) dynamic update of the reference colors. The operator can see the effects of the previous motion which enables making the necessary corrections through repetitive operator hand-eye interactions. Evaluation shows that the static and dynamic errors of the tracking algorithm are 0.1% and 0.6% for a centered workspace of 20/sup 3/ in/sup 3/ that is 40-60 in away from the cameras. Running the tracking algorithm on two PCs in parallel allowed: 1) a parallel image grabbing delay of 60 ms; 2) a stereo matching delay of 50 ms; and 3) a global refresh rate of 9 Hz.
34. Choon-Young Lee, J.-J. Lee, "Multiple neuro-adaptive control of robot manipulators using visual cues," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 320- 326, Feb. 2005. Full Text Link Abstract : A new adaptive controller based on multiple neural networks (NNs) for an uncertain robot manipulator system is developed in this paper. The proposed multiple neuro-adaptive controller (MNAC) switches to a memorized control skill or blends multiple skills by using visual information on the given job to improve the transient response at the time of task variation like a change of manipulating object. MNAC is a type of adaptive feedback controller where system nonlinearity terms are approximated with multiple NNs. The proposed controller is effective for a job where some tasks are repeated but information on the load cannot be scheduled before the operation. During the learning phase, MNAC memorizes a control skill for each load with each NN. For a new task, most similar existing control skills may be used as a starting point of adaptation, which improves the performance of learning. Lyapunov-function-based design of MNAC guarantees the stability of the closed-loop system to be independent of switching or blending law. Simulation results on a two-link manipulator for changing the mass of the given load were illustrated to show the effectiveness of the proposed control scheme by comparison with the conventional neuro-adaptive controller.
Signal Processing And Control
35. Tzung-Her Chen, G. Horng, Wei-Bin Lee, "A publicly verifiable copyright-proving scheme resistant to malicious attacks," IEEE Trans. on Industrial Electronics, vol. 52, no. 1, pp. 327- 334, Feb. 2005. Full Text Link Abstract : A wavelet-based copyright-proving scheme that does not require the original image for logo verification is proposed in this paper. The scheme is strong enough to resist malicious manipulations of an image including blurring, JPEG compression, noising, sharpening, scaling, rotation, cropping, scaling-cropping, and print-photocopy-scan attacks. The proposed scheme is also resistant to StirMark and unZign attacks and it is not only a robust method but also a lossless one. Experiments are conducted to show the robustness of this method. Moreover, cryptographic tools, such as digital signature and timestamp, are introduced to make copyright proving publicly verifiable.
IEEE Transactions on Industrial Electronics
