IEEE Transactions on Industrial Electronics 

Volume 37,  Number 6, Dec 1990           Access to the journal on IEEE XPLORE     IE Transactions Home Page



37.6.1    V. Catania, L. Milazzo, A. Puliafito, L. Vita, "Enhancing reliability in an industrial LAN: design and performability evaluation," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 433-441, Dec 1990.   Abstract Link    Full Text

Abstract: A fault-tolerant fiber-optic LAN (local area network) is presented and assessed. The reliability of this LAN has been increased by introducing redundancy into the physical transmission medium and by providing the network with a monitor process that is capable of detecting and isolating faults automatically. The network is modeled by applying Markov process theory, through which the mean time to failure (MTTF) and performability are assessed. The results obtained show that the network exhibits a significant increase in MTTF and performability, which is all the more evident if the coverage factor c is closer to 1 and if the number of stations is higher. Redundancy in the transmission medium and the monitor process enable the network to overcome the typical reliability limitations affecting ring topologies and allow it to be used in some critical industrial applications

37.6.2    P. Montuschi, A. Valenzano, L. Ciminiera, "Selection of token holding times in timed-token protocols," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 442-451, Dec 1990.   Abstract Link    Full Text

Abstract: Minimum requirements for the high-priority token holding time (HPTHT) in a network using timed token access protocols (such as IEEE 802.4 and FDDI) are derived in order to ensure that the throughput of synchronous messages is no lower than the amount of traffic generated for that class. The minimal value is essential in order to avoid unbounded queue length for the synchronous class as well as to achieve high network responsiveness. The results have been obtained for synchronous messages generated according to a generic periodic pattern with no constraint for the shape and for the period of the pattern. The manner in which the theoretical results obtained can be used to tune the network performance is also shown

37.6.3    Fu-Juay Chang, Hsiang-Ju Liao, Shyand Chang, "Position control of DC motors via variable structure systems control: a chattering alleviation approach," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 452-459, Dec 1990.   Abstract Link    Full Text

Abstract: A novel chattering alleviation control (CAC) algorithm is proposed for variable structure systems (VSSs). Both analog and digital controllers using the theory of CAC are applied to the position control problem of a DC servomotor system. Comparisons of the CAC with other VSS control algorithms indicate that the chattering can be alleviated. Since the input of the CAC method contains only low-frequency components, it will not excite unmodeled high-frequency plant dynamics

37.6.4    N. Hemati, J.S. Thorp, M.C. Leu, "Robust nonlinear control of brushless DC motors for direct-drive robotic applications," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 460-468, Dec 1990.   Abstract Link    Full Text

Abstract: The control problem associated with brushless DC motors (BLDCMs) for direct-drive robotic applications is considered. In order to guarantee the high-performance operation of BLDCMs in such applications, the effects of reluctance variations and magnetic saturation are accounted for in the model. Such a BLDCM model constitutes a highly coupled and nonlinear dynamic system. Using the transformation theory of nonlinear systems, a feedback control law, which is shown to compensate for the system nonlinearities, is derived. Conditions under which such a control law is possible are presented. The need for the derivation of explicit commutation strategies is eliminated, resulting in reduction of the computations involved. To guarantee the high-performance operation of the system under substantial uncertainties, a robust control law is derived and appended to the overall control structure. The inclusion of the robust controller results in good tracking performance when there are modeling and measurement errors and payload uncertainties. The efficacy of the overall control law is investigated by considering a single-link direct-drive arm actuated by a BLDCM

37.6.5    R. Krishnan, P.N. Materu, "Design of a single-switch-per-phase converter for switched reluctance motor drives," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 469-476, Dec 1990.   Abstract Link    Full Text

Abstract: The main considerations in the design of a single-switch-per-phase converter for a switched reluctance motor (SRM) drive are described, with particular attention given to the choice of converter topology, the type of switching devices, the normalized rating of the power devices, and input filter design. The converter uses MOSFET switches. Experimental verification is included with a 6/4 pole personal-computer-controlled prototype SRM drive

37.6.6    C.C. Chan, H. Wang, "An effective method for rotor resistance identification for high-performance induction motor vector control," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 477-482, Dec 1990.   Abstract Link    Full Text

Abstract: An effective method for rotor resistance identification is presented for the purpose of improving the performance of vector control of induction motor drives. The method is mathematically derived from proper selection of coordinate axes and utilization of the steady-state model of the induction motor. The major advantages of the method lie in its simplicity and accuracy. A series of computer simulations has been performed with very satisfactory results

37.6.7    I. Avitan, V. Skormin, "Mathematical modeling and computer simulation of a separately excited DC motor with independent armature/field control," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 483-489, Dec 1990.   Abstract Link    Full Text

Abstract: A mathematical model of a separately excited DC motor, providing an in-depth description of major physical transformations, is developed. The model is implemented in computer simulation code which, in combination with a SIMPLEX optimization procedure, is used for parameter estimation and model verification. The model is suggested as a basis for development of microprocessor-based control procedures providing additional flexibility as well as optimizing motor performance

37.6.8    S.S. Valtchev, J.B. Klaassens, "Efficient resonant power conversion," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 490-495, Dec 1990.   Abstract Link    Full Text

Abstract: The DC analysis of a series-resonant converter operating above resonant frequency is presented. The results are used to analyze the current form factor and its effect on the efficiency. The selection of the switching frequency to maximize the efficiency is considered. The derived expressions are generalized and can be applied to calculations in any of the switching modes for a series-resonant circuit. For switching frequencies higher than the resonant frequency, an area of more efficient operation is indicated which will aid in the design of this class of converters and power supplies. It is pointed out that (especially for power MOSFETs where ohmic losses dominate) it is more attractive to select switching frequencies that are higher than the resonant frequency because of the possibility of nondissipative snubbers. Slowing down the rise of the gate voltage and, hence, the slow decrease of ON resistance during turn-on is also not a drawback to high-frequency switching. Because of this safer operation, the standard intrinsic diode of the power MOSFET could be used at high frequencies instead of the more expensive FREDFET

37.6.9    L.D. Salazar, P.D. Ziogas, "A high-frequency two-switch forward converter with optimized performance," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 496-505, Dec 1990.   Abstract Link    Full Text

Abstract: The analysis and design of a high-frequency two-switch forward converter topology with transformer flux balancing and extended duty cycle capability are presented. To improve converter performance, an auxiliary circuit connected in parallel with each power switch is proposed. This auxiliary circuit uses a low-power switch or a nonlinear resistor connected in series with a capacitor. As a result, the DC component of the magnetizing current is minimized, and the converter provides the means of recovering the energy associated with the parasitic inductances of the circuit components. Thus, higher than usual efficiency and higher operating frequencies are obtained. Experimental results are presented for a 4 kW, 40 kHz prototype unit

37.6.10    J. Holtz, K.-H. Werner, "Multi-inverter UPS system with redundant load sharing control," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 506-513, Dec 1990.   Abstract Link    Full Text

Abstract: The concept of a redundant multi-inverter UPS (uninterruptible power supply) system which includes extended monitoring of the status and the operating conditions of all power electronic equipment is described. Each block of the UPS system is monitored by two independent microcomputers that process the same data. The microcomputers are part of a redundant distributed monitoring system that is separately interlinked by two serial data buses through which they communicate. They establish a hierarchy among the participating blocks by defining one of the healthy inverter blocks as the master. The actual master runs the central synchronizing unit for the entire system, whereas the slave units perform the control of equal active and reactive load sharing. Operation and fault detection are experimentally illustrated in a dual inverter system with a rating of 10 kVA of redundant power

37.6.11    F.J. Gracia, F. Arizti, F.J. Aranceta, "A nonideal macromodel of thyristor for transient analysis in power electronic systems," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 514-520, Dec 1990.   Abstract Link    Full Text

Abstract: A nonideal SCR (silicon controlled rectifier) macromodel for analog power circuit simulation using SPICE has been developed. This model adds important second-order effects such as overvoltage and critical dVAk/dt switch-on, turn-on, and tq times, threshold gate trigger voltage, and nonlinear on-state characteristics. The parameters of any specific SCR can be easily obtained from its data sheet specifications. Any kind of thyristor, from high power up to fast turn-off, can be modeled with only 10 well-defined parameters. Electronic systems with electrical transients can be successfully simulated. Good agreement between manufacturer data sheet specifications and simulated results has been observed for all the thyristors considered

37.6.12    A.R. Prasad, P.D. Ziogas, S. Manias, "A novel passive waveshaping method for single-phase diode rectifiers," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 521-530, Dec 1990.   Abstract Link    Full Text

Abstract: A novel passive waveshaping method for single-phase diode rectifiers is presented. It is shown that application of the proposed method maintains high-input power factor, lowers rectifier current stresses, and lowers the volt-ampere (VA) rating of the associated reactive components as compared to the standard diode rectifier. Relevant input and output current waveforms, component ratings, and power factor values are derived. Different modes of operation are discussed as a means of obtaining high performance. Key predictions, such as input/output waveforms and associated harmonic spectra, have been verified experimentally on a 1 kVA laboratory prototype unit

37.6.13    N. Ammasaigounden, M. Subbiah, "Microprocessor-based voltage controller for wind-driven induction generators," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 531-537, Dec 1990.   Abstract Link    Full Text

Abstract: A microprocessor-based closed-loop system has been developed for wind-driven self-excited induction generators using a controlled rectifier to maintain a constant DC load voltage with varying rotor speeds. The configuration and implementation of the control scheme are described. Test results on a self-excited induction generator demonstrate the satisfactory performance of both the hardware and the software of the control scheme, and the utility of the set-up as a whole. The steady-state analysis of the generator is extended to include the controlled rectifier, and the performance characteristics are predicted

37.6.14    Y.-Q. Shi, K.K. Yen, D. Zhang, "Improved stability robustness of linear discrete-time systems via a linear fractional transformation," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 538-543, Dec 1990.   Abstract Link    Full Text

Abstract: Through a linear fractional transformation in the frequency domain, a set of hyperellipsoids, containing only such points in the coefficient space which correspond to stable polynomials in linear discrete-time systems, was obtained. Procedures for searching for a suitable transform parameter β that will achieve a possibly larger coefficient perturbation range (with guaranteed stability) than that obtained by C.B. Soh et al. (1985) are presented. When β=0, the hyperellipsoid degenerates to the largest hypersphere. The result in this work is, therefore, a generalization of the result obtained by C.B. Soh et al

37.6.15    M.M. Jovanovic, C.-S. Leu, F.C.Y. Lee, "Zero-voltage-switched multiresonant converter for high-power, pulse-load applications," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 544-555, Dec 1990.   Abstract Link    Full Text

Abstract: A full-bridge zero-voltage-switched (ZVS) multiresonant converter (MRC) was built for a pulse load with a peak power of 1.44 kW and an average power of 360 W. The converter works with an input-voltage range from 220 to 350 V, and delivers 32 V to the pulse load with a constant peak current of 45 A. The efficiency range of the converter was measured from 82.5 to 90.5%. The maximum efficiency occurs at low line and decreases as the input voltage increases. Detailed analysis and design of the converter, along with experimental results, are presented

37.6.16    D.C. Hanselman, "Resolver signal requirements for high accuracy resolver-to-digital conversion," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 556-561, Dec 1990.   Abstract Link    Full Text

Abstract: Tracking resolver-to-digital (R/D) conversion has emerged as the most robust method for obtaining high-resolution position information from resolvers. When driven by ideal resolver signals, tracking R/D converters currently offer position resolutions up to 216 quantization intervals/period (16-b resolution), and accuracies to 214 intervals/period (14-b accuracy). The effects of nonideal resolver signal characteristics commonly encountered in practice are investigated. Expressions for the position error reported by an R/D converter due to amplitude imbalance, quadrature error, inductive harmonics, reference phase shift, excitation signal distortion, and disturbance signals are found. From these expressions, bounds on the position accuracy achievable in practical resolver-based position-sensing systems are determined

37.6.17    P.C. Sen, "Electric motor drives and control-past, present, and future," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 562-575, Dec 1990.   Abstract Link    Full Text

Abstract: A comprehensive review of the state of the art in the field of electric motor drives and control strategies is presented. It is pointed out that drive technology has seen impressive growth during the last three decades. Recent advances in semiconductor power electronics and microelectronics have made is possible to use AC motors in many variable-speed drive applications. Implementation of new control techniques, such as field-oriented control and variable-structure control with sliding-mode features, has made AC motors a viable alternative to DC motors in high-performance drive applications. The advent of microprocessors/microcontrollers/microcomputers has made it possible to implement these complex control techniques

37.6.18    Z.O. Yonah, A.M. El-Serafi, A.E. Krause, "On the use of a digital computer as a two-phase variable-amplitude variable-frequency oscillator," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 576-581, Dec 1990.   Abstract Link    Full Text

Abstract: A feasibility study on the use of a digital computer as a variable-amplitude variable-frequency oscillator which generates two-phase sinusoidal excitation control signals for a dual-excited synchronous generator is described. The oscillator uses two input signals. One input signal is used to control the frequency of the oscillator outputs, and the other is used to control their amplitudes. By a single variable, the software can be configured to vary the oscillator frequency range and to greatly reduce (almost eliminate) the harmonic distortion of the output signals. The harmonic distortion is constant and independent of the output frequency for each possible oscillator frequency range. The software-based oscillator design is flexible and can be used to generate different types of multiphase signal waveforms

37.6.19    E.J. Tacconi, R.J. Mantz, "Linearization and feedforward compensation for switching systems ," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 581-584, Dec 1990.   Abstract Link    Full Text

Abstract: The linearization of a switching system including a feedforward compensation for power supply perturbations is obtained by the addition of a high-frequency signal. A general expression for the required shape and amplitude of this high-frequency signal is derived. The method is analyzed for its application to AC phase control systems. The method is outlined for the case of a DC electric motor phase control. It is then generalized to any nonlinear switching system

37.6.20    M. Bramanti, "A high sensitivity measuring technique for capacitive sensor transducers," IEEE Trans. on Industrial Electronics, vol. 37, no. 6, pp. 584-586, Dec 1990.   Abstract Link    Full Text

Abstract: A measuring technique is proposed for a capacitive-type sensor that has been developed to measure the density of dielectric powder gaseous suspensions. The basic principle of the proposed technique is to measure the variations of sensor capacitance by measuring the phase shift between voltage and current in a series RLC circuit tuned to resonance. Experimental results obtained with the technique are presented