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Showing papers on "AC power published in 1995"


Journal ArticleDOI
TL;DR: In this paper, the authors proposed a unified power flow controller (UPFC) that is able to control both the transmitted real power and, independently, the reactive power flows at the sending-and the receiving-end of the transmission line.
Abstract: This paper shows that the unified power flow controller (UPFC) is able to control both the transmitted real power and, independently, the reactive power flows at the sending- and the receiving-end of the transmission line. The unique capabilities of the UPFC in multiple line compensation are integrated into a generalized power flow controller that is able to maintain prescribed, and independently controllable, real power and reactive power flow in the line. The paper describes the basic concepts of the proposed generalized P and Q controller and compares it to the more conventional, but related power flow controllers, such as the thyristor-controlled series capacitor and thyristor-controlled phase angle regulator. The paper also presents results of computer simulations showing the performance of the UPFC under different system conditions. >

997 citations


Journal ArticleDOI
TL;DR: In this article, the authors presented a new algorithm for studying the load shedding and generation reallocation problem in emergencies where a portion of the transmission system is disabled and an AC power solution cannot be found for the overloaded system.
Abstract: This paper outlines the optimization problem of real and reactive power, and presents the new algorithm for studying the load shedding and generation reallocation problem in emergencies where a portion of the transmission system is disabled and an AC power solution cannot be found for the overloaded system. The paper describes a novel and efficient method and algorithm to obtain the optimal shift in power dispatch related to contingency states or overload situations in power system operation and planning phases under various objectives such as economy, reliability and environmental conditions. The optimization procedures basically utilize linear programming with bounded variables and it incorporates the techniques of the Section Reduction Method and the Third Simplex Method. The validity and effectiveness of the algorithm is verified by means of two examples: a 10-bus system and the IEEE 30-Bus, six generators system. >

442 citations


Journal ArticleDOI
TL;DR: The Static Condenser (STATCON) as discussed by the authors is a static condenser that is similar to the rotating synchronous condenser (SVC) and has similar output characteristics to those of the SVC.
Abstract: The availability of high power gate-turn-off (GTO) thyristors has led to the development of controllable reactive power sources, using electronic switching power converters, for use in power transmission systems This new technology has resulted in equipment that is fundamentally different from the conventional thyristor-controlled static VAr compensator (SVC) The new equipment is called a static condenser (STATCON) because its steady state output characteristics are similar to those of the rotating synchronous condenser The paper describes the fundamental operating principles, functional characteristics and basic control approach of the STATCON, with particular reference to a /spl plusmn/100 MVAr prototype planned to be installed at the Tennessee Valley Authority (TVA) Sullivan substation, USA This installation will be the first demonstration of a STATCON under the EPRI flexible AC transmission systems (FACTS) program, and will be the largest installation of its type in the world >

380 citations


Journal ArticleDOI
01 Apr 1995
TL;DR: In this article, a guideline for scaling of CMOS technology for logic applications such as microprocessors is presented covering the next ten years, assuming that the lithography and base process development driven by DRAM continues on the same three-year cycle as in the past.
Abstract: A guideline for scaling of CMOS technology for logic applications such as microprocessors is presented covering the next ten years, assuming that the lithography and base process development driven by DRAM continues on the same three-year cycle as in the past. This paper emphasizes the importance of optimizing the choice of power-supply voltage. Two CMOS device and voltage scaling scenarios are described. One optimized for highest speed and the other trading off speed improvement for much lower power. It is shown that the low power scenario is quite close to the original constant electric-field scaling theory. CMOS technologies ranging from 0.25 /spl mu/m channel length at 2.5 V down to sub-0.1 /spl mu/m at 1 V are presented and power density is compared for the two scenarios. Scaling of the threshold voltage along with the power supply voltage will lead to a substantial rise in standby power compared to active power and some tradeoffs of performance and/or changes in design methods must be made. Key technology elements and their impact on scaling are discussed. It is shown that a speed improvement of about 7/spl times/ and over two orders of magnitude improvement in power-delay product (mW/MIPS) are expected by scaling of bulk CMOS down to the sub-0.1 /spl mu/m regime as compared with today's high performance 0.6 /spl mu/m devices at 5 V. However, the power density rises by a factor of 4/spl times/ for the high-speed scenario. The status of the silicon-on-insulator (SOI) approach to scaled CMOS is also reviewed, showing the potential for about 3/spl times/ savings in power compared to the bulk case at the same speed. >

351 citations


Journal ArticleDOI
TL;DR: In this article, an evolutionary programming (EP) method was applied to optimal reactive power dispatch and voltage control for large-scale power systems, and the proposed method has been evaluated on the IEEE 30-bus system.
Abstract: This paper is concerned with application of evolutionary programming (EP) to optimal reactive power dispatch and voltage control of power systems. Practical implementation of the EP for global optimization problems of large-scale power systems has been considered. The proposed EP method has been evaluated on the IEEE 30-bus system. Simulation results, compared with those obtained using a conventional gradient-based optimization method, are presented to show the potential of application of the proposed method to power system economical operations. >

340 citations


Journal ArticleDOI
TL;DR: In this paper, the authors presented the general equations that relate the new concepts of instantaneous active and reactive power theory and the well known theory of symmetrical components for the case of 3-phase 4-wire systems, where zero sequence components and harmonics may be present in both voltages and currents.
Abstract: This paper presents the general equations that relate the new concepts of instantaneous active and reactive power theory and the well known theory of Symmetrical Components, for the case of 3-phase 4-wire systems, where zero sequence components and harmonics may be present in both voltages and currents. Based on these equations, new control algorithms for 3-phase 4-wire shunt and series active filters for unbalanced power systems are proposed and validated through simulations. The control algorithms presented here are very important for active power filter design and also for FACTS technology reactive power compensators. >

328 citations


Journal ArticleDOI
TL;DR: Experimental results obtained from a 5 kVA prototype confirm the feasibility and the features of the proposed active power filter, which can compensate the reactive power and the current harmonic components of nonlinear loads.
Abstract: The performance and dynamic characteristics of a three-phase active power filter operating with fixed switching frequency is presented and analyzed in this paper. The proposed scheme employs a PWM voltage-source inverter and has two important characteristics. First, it operates with fixed switching frequency, and second, it can compensate the reactive power and the current harmonic components of nonlinear loads. Reactive power compensation is achieved without sensing and computing the reactive component of the load current, thus simplifying the control system. Current harmonic compensation is done in time domain. The principles of operation of the proposed active power filter along with the design criteria of the power and control circuit components are discussed in detail. Finally, experimental results obtained from a 5 kVA prototype confirm the feasibility and the features of the proposed system. >

302 citations


Proceedings ArticleDOI
08 Oct 1995
TL;DR: A new three phase to three-phase converter for AC motor drives is proposed that employs only eight switches and has the capability of delivering sinusoidal input currents with unity power factor and bidirectional power flow.
Abstract: A current-controlled VSI-PWM rectifier and inverter with capacitor DC link is regarded as one of the most important structures for three-phase to three-phase power conversion. This type of power converter normally requires twelve switches for the rectifier and an inverter composed of self turnoff switch such as a bipolar transistor or an IGBT with an anti-parallel diode. In this paper, a new three-phase to three-phase AC/AC power converter for AC motor drives is proposed. The proposed power converter employs only eight switches and has the capability of delivering sinusoidal input currents with unity power factor and bidirectional power flow. This paper describes the feasibility and the operational limitations of the proposed structure. A mathematical model of the system is derived using the generalized modulation theory and experimental results for steady-state and dynamic behavior are presented to verify the developed model.

253 citations


Journal ArticleDOI
TL;DR: In this article, the authors introduce the family of quasi-direct converters, i.e., forced-commutated AC/DC/AC power converters including small energy storage devices in the DC link.
Abstract: The paper introduces the family of quasi-direct converters, i.e., forced-commutated AC/DC/AC power converters including small energy storage devices in the DC link. In particular, the case of the three-phase to three-phase quasi-direct power converter is considered. Since energy storage minimization calls for instantaneous input/output power balance, a proper control strategy is needed. The paper describes a simple and effective control technique which also provides high-power factor and small distortion of the supply currents. After a discussion of the general properties of quasi-direct power converters, design criteria of both power and control sections are given, and experimental results of a 2-kVA prototype are reported. >

212 citations


Journal ArticleDOI
TL;DR: In this article, the authors present preliminary results from a national monitoring program designed to characterize power quality levels on electric distribution systems, which is being sponsored by the Electric Power Research Institute.
Abstract: This paper presents preliminary results from a national monitoring program designed to characterize power quality levels on electric distribution systems. The monitoring program is being sponsored by the Electric Power Research Institute. Initial stages of the project resulted in the development of a new power quality monitoring instrument (designated the PQNode). This instrument permits simultaneous monitoring of steady state quantities (RMS voltage and current, harmonic distortion levels, power factor, etc.) and disturbances (voltage sags, overvoltages, transients, etc.). Approximately 200 PQNodes have been installed on distribution systems of 24 different utility companies. Monitoring data is being compiled by Electrotek Concepts in Knoxville, TN. The paper describes the monitoring system and presents preliminary results of the monitoring effort. >

183 citations


Patent
20 Jun 1995
TL;DR: In this paper, a non-contacting charging device is described, in which electric power of a charger is supplied without direct contact to a storage battery, and which includes in the charger 1 a primary coil 103 and circuits 104, 105 for supplying AC power to the primary coil, and also in the radio communication device having a stored battery 210, a secondary coil 212 that couples electromagnetically with the primary coils 103 and a circuit 211 for supplying the induced current power generated in the secondary coil to the storage battery as charging power.
Abstract: A non-contacting charging device is disclosed which performs charging in which electric power of a charger 1 is supplied without direct contact to a storage battery 210, and which includes in the charger 1 a primary coil 103 and circuits 104, 105 for supplying AC power to the primary coil, and also includes in the radio communication device having a storage battery 210, a secondary coil 212 that couples electromagnetically with the primary coil 103 and a circuit 211 for supplying the induced current power generated in the secondary coil to the storage battery as charging power. This device is provided with halt signal generating circuits 203, 209, and 214 for generating a halt signal that commands a halt of supply of AC power to the primary coil, and a halting circuit for halting supply of AC power to the primary coil in response to a halt signal, the halt signal generating circuit being provided in the radio communication device. If it is necessary to make or receive a call during charging of the radio communication device, a halt signal is generated on the radio communication device side to halt charging, thereby eliminating the attractive force caused by the electromagnetic induction in effect between the radio communication device and the charger, and allowing removal of the radio communication device from the charger with a minimum of effort.

Journal ArticleDOI
01 Nov 1995
TL;DR: In this paper, the authors investigated reactive power/voltage control in a distribution substation and proposed an approach based on dynamic programming to reach the desired dispatching schedule, where the shunt capacitors and onload tap changers were properly dispatched based on the forecast hourly loads of a main transformer and its primary bus voltage such that reactive power flows through the main transformer, and the transformer secondary bus voltage deviations from the desired values can be minimised.
Abstract: The reactive power/voltage control in a distribution substation is investigated. The purpose is to properly dispatch the shunt capacitors and onload tap changers at the distribution substation based on the forecast hourly loads of a main transformer and its primary bus voltage such that the reactive power flows through the main transformer, and the transformer secondary bus voltage deviations from the desired values can be minimised. Practical constraints on secondary bus voltage limits and the maximum allowable number of switching operations in a day for the onload tap changers are taken into account. An approach based on dynamic programming is presented to reach the desired dispatching schedule. To demonstrate the usefulness of the proposed approach, reactive power/voltage control in a distribution substation within the service area of Taipei City District Office of Taiwan Power Company is performed. It is found that a proper dispatching schedule for the shunt capacitors and onload tap changers can be reached by the proposed method.

Journal ArticleDOI
TL;DR: A new real-time detecting method based on adaptive interference canceling theory for harmonic and reactive currents that is useful for dynamic compensation equipment such as active power filters, static VAr compensators, etc.
Abstract: The conventional detecting methods for power system harmonic and reactive currents have various limitations. Based on adaptive interference canceling theory, a new adaptive detecting method for harmonic and reactive currents is presented, the corresponding detection system is developed, and experiments are performed which verify the feasibility of the method proposed. The new real-time detecting method is useful for dynamic compensation equipment such as active power filters, static VAr compensators, etc. >

Journal ArticleDOI
TL;DR: In this paper, the interactions between the incremental changes of current harmonic phasors injected by a power system NL (nonlinear load) and the resulting variations of harmonic voltages and powers are analyzed.
Abstract: This paper analyses the interactions between the incremental changes of current harmonic phasors injected by a power system NL (nonlinear load) and the resulting variations of harmonic voltages and powers. It proves that it is not always possible, following simple measurements of individual harmonic powers, to decide if a certain harmonic current is harmful or useful. It is suggested that the NL "distortion" be evaluated with the help of a quantity called non60 Hz (nonfundamental) apparent power. >

Journal ArticleDOI
TL;DR: In this paper, a new incremental model of a battery energy storage system (BES) is presented and merged into the load-frequency control of a power system, which is suitable for charging mode and discharging mode operations.
Abstract: Since a battery energy storage system (BES) can provide fast active power compensation, it also can be used to improve the performance of load-frequency control. In this paper a new incremental model of a BES is presented and merged into the load-frequency control of a power system. A comprehensive digital computer model of a two-area interconnected power system including governor deadband and generation rate constraint is employed for a realistic response. Computer simulations show that the BES is very effective in damping the oscillations caused by load disturbances. The BES model is suitable for charging mode and discharging mode operations. Optimization of controller gains is obtained by the second method of Lyapunov. >

Journal ArticleDOI
S. Corsi1, P. Marannino1, N. Losignore1, G. Moreschini1, G. Piccini1 
TL;DR: In this article, the control strategies adopted at ENEL (the Italian Electric Power Company) for the automatic voltage regulation and for the short and very short term reactive power scheduling are presented.
Abstract: The paper presents the control strategies adopted at ENEL (the Italian Electric Power Company) for the automatic voltage regulation and for the short and very short term reactive power scheduling. The advanced project is based upon a three level hierarchical control of voltage and reactive power (primary, secondary and tertiary regulation) and a reactive power dispatch procedure. The three levels are characterized by specific control actions which affect systems of different size and complexity, operating in three steps. In particular, the slowest third level executes the optimal voltage profile defined by the short or very short term reactive power scheduling. The need of an effective co-ordination between the off-line reactive scheduling procedures and the on-line voltage control is pointed out in the work. Besides, the paper presents a computation procedure realized in order to simulate the steady state behaviour of the electric power system submitted to the hierarchical voltage control system and its interaction with the VAr optimisation program. >

Proceedings ArticleDOI
05 Mar 1995
TL;DR: A survey of PWM boost rectifier circuit topologies for controlling a nonisolated DC-rail voltage whilst drawing supply currents at a unity fundamental power factor and with a low total harmonic distortion is provided in this paper.
Abstract: This paper provides a survey of PWM boost rectifier circuit topologies for controlling a nonisolated DC-rail voltage whilst drawing supply currents at a unity fundamental power factor and with a low total harmonic distortion. Rectifier-leg topologies are classified by the number of switches and by the PWM waveforms generated. Complete rectifier circuit topologies are described for operation off 1-phase and 3-phase AC supplies. Circuit analogies are made between rectifiers for 1 and 3 phases, rectifiers using either a single or a split DC-rail and between rectifiers using either AC or DC side inductors. The performances of the various circuits are assessed with reference to factors such as conduction losses, efficiency, switch count, semiconductor voltage stresses, 3-level and 2-level PWM voltage waveforms and, finally, bi-directional power conversion. >

Journal ArticleDOI
TL;DR: In this article, a simple bus-wise cost-benefit analysis (CBA) scheme is proposed which involves solving a modified optimal power flow problem (OPF) iteratively, and a two-part reactive power spot-pricing scheme is formulated, by which the investment and operational costs can be recovered by the utility.
Abstract: The paper presents an integrated framework to analyze the issues of reactive power planning along with reactive power pricing. The planning problem involves optimal placement and sizing of capacitors in a network such that operating and investment costs are minimum. A simple bus-wise cost-benefit analysis (CBA) scheme is proposed which involves solving a modified optimal power flow problem (OPF) iteratively. The proposed CBA incorporates detailed hourly loading conditions at a bus and achieves a fairly accurate estimate of the benefits from capacitor placement. The formulation is directly handled by the well known MINOS code and is solved efficiently. It obviates the need to introduce integer variables and is thus suitable for large system applications. A two-part reactive power spot-pricing scheme is formulated, by which the investment and operational costs can be recovered by the utility. The proposed reactive power price has two parts-a fixed part to account for the investment costs of new capacitor at a bus and a variable spot price to account for the operating costs incurred in supplying the additional reactive power from generating units.

Journal ArticleDOI
TL;DR: In this paper, a generic model of dynamic loads is used to investigate the influence of active and reactive power dynamics on the damping of oscillations in a multimachine power system.
Abstract: This paper considers the significance of load voltage dynamics in studies of power system damping. A generic model of dynamic loads is used to investigate the influence of active and reactive power dynamics on the damping of oscillations in a multimachine power system. The interaction between the load and the power system is explored in terms of load and system transfer functions. It is shown that the power system transfer function is composed of a static part and a dynamic part. The static part is derived from the power flow Jacobian. The investigations indicate that load voltage dynamics can significantly influence the damping of modal oscillations. Static load models can give quite misleading predictions of damping when loads actually exhibit dynamic behaviour.

Patent
Keiji Suzuki1, Yohichi Kozasu1
14 Aug 1995
TL;DR: In this article, a power supply circuit is proposed to prevent the flow of reverse current from a battery to an AC power adaptor when the power adaptors is disconnected from its external power source.
Abstract: A power supply circuit prevents, without the use of a series diode, the flow of reverse current from a battery to an AC power adaptor when the power adaptor is disconnected from its external power source. The circuit includes both voltage and current detectors to determine if the output voltage and current of the power adaptor are above or below predetermined reference levels. A summing circuit sums the outputs of the voltage and current detectors, and when both the detected voltage and current are below the reference levels, a switch disconnects the battery from the output terminal of the power adaptor, thereby preventing reverse current flow.

Journal ArticleDOI
TL;DR: In this article, a voltage proximity index is calculated based on the voltage phasor values only, and an algorithm is derived which automatically detects the network transmission paths to the load nodes which are prone to voltage collapse due to additional real or reactive loading.
Abstract: In the paper, a "phasor concept" of voltage collapse proximity determination is presented. An adequate voltage proximity index is calculated based on the voltage phasor values only. Furthermore, an algorithm is derived which automatically detects the network transmission paths to the load nodes which are prone to voltage collapse due to additional real or reactive loading. The algorithm is tested on practical networks and exhibits comparable accuracy to the existing methods and low computing time consumption. >

Journal ArticleDOI
N. H. Dandachi1, M.J. Rawlins1, O. Alsac, M. Prais, B. Stott 
TL;DR: In this article, the authors describe the reactive pricing problem being addressed, the modeling requirements, and the resulting extensions made to the optimal power flow (OPF) formulation and package.
Abstract: Retail transmission services like those being provided by the National Grid Company (NGC) in England and Wales pose new challenges for the pricing of reactive power supply. A reactive power market approach has been proposed by NGC and continues to be evaluated. Such an approach includes a novel requirement for transmission constrained economic dispatch of VAr, a problem in the security constrained optimal power flow (OPF) class. The problem formulations handled by the OPF package in use could not accommodate NGC's requirements. This paper describes the reactive pricing problem being addressed, the modeling requirements, and the resulting extensions made to the OPF formulation and package. It discusses the test results obtained to date on the NGC system.

Journal ArticleDOI
TL;DR: In this paper, the basic role of a secondary voltage control in a multi-regional electric power system is reviewed, and the theoretical developments are illustrated on two regions of the French electric power network.
Abstract: In this paper the basic role of a secondary (regional level) voltage control in a multi-regional electric power system is reviewed. Specifically, certain limitations of presently implemented control schemes are described. Next an improved secondary voltage control (ISVC) scheme is proposed. In the second part of the paper, possible enhancements of a multi-regional power system operation by means of scheduled, tertiary voltage control (TVC) interactions are proposed. It is shown that the prime role of a TVC is in managing limits on voltage control devices, such as generators. The theoretical developments are illustrated on two regions of the French electric power network.

Journal ArticleDOI
TL;DR: In this paper, the authors proposed a new method of harmonic power detection based on the instantaneous active power in three-phase circuits, and its applications to search for dominant harmonic sources in power systems.
Abstract: This paper presents a new method of harmonic power detection based on the instantaneous active power in three-phase circuits, and its applications to search for dominant harmonic sources in power systems. The proposed method requires only band elimination filters and a three-phase active power meter to detect the harmonic active power, and it is able to deal with harmonic power flow more easily and precisely than a conventional meter which is based on Fourier series of single-phase circuits. In addition, measurement errors of the harmonic power are discussed theoretically. The validity of the proposed method is demonstrated by digital simulation. >

Journal ArticleDOI
01 Jul 1995
TL;DR: In this paper, a useful and systematic dynamic model of a battery energy storage system (BES) was developed for a large-scale power system stability study, taking into account converter equivalent circuits, battery characteristics and internal losses.
Abstract: A useful and systematic dynamic model of a battery energy storage system (BES) is developed for a large-scale power system stability study. The model takes into account converter equivalent circuits, battery characteristics and internal losses. Both charging mode and discharging mode are presented. The model is expressed in equivalent transfer function blocks, and it can be easily used in dynamic stability analysis of a power system. To examine the dynamic behaviour of the model, applications to the damping of turbogenerator torsional oscillations are performed. Active and reactive power modulation by the BES can be controlled according to system requirements. Eigenvalue analysis and dynamic simulations are performed to demonstrate the damping effect of the BES.

Journal ArticleDOI
08 Oct 1995
TL;DR: In this article, the analysis and minimization of the ripple components of the input current and voltage of three-phase voltage-source pulsewidth modulated (PWM) inverters are presented.
Abstract: Analysis and minimization of the ripple components of the input current and voltage of three-phase voltage-source pulsewidth modulated (PWM) inverters are presented in this paper. The analytical expressions for the rms values of the input current and voltage ripples as a function of the shape of the PWM reference signal are derived. It is found that the reference signal which produces a minimum ripple in the input voltage varies as a function of the load power factor. It is also found that the rms value of the inverter input current ripple does not depend on the shape of the reference signal. In respect of the inverter input current and voltage ripples, the addition of harmonics other than the third into the sinusoidal reference is neither useful nor necessary. Experimental results are included to verify the derived expressions.

Journal ArticleDOI
TL;DR: In this article, the authors proposed a new performance index that provides a direct relationship between its value and the amount of load demand that the system can withstand before collapse, which can answer questions such as: "can the system withstand another 100 MVar increase on bus 11?"
Abstract: Voltage collapse is generally caused by either of two types of power system disturbances: load variations; and contingencies. A number of performance indices intended to measure the severity of the voltage collapse problem have been proposed in the literature. However, few of these performance indices can answer questions such as: "can the system withstand another 100 MVar increase on bus 11?" This paper presents a new performance index that provides a direct relationship between its value and the amount of load demand that the system can withstand before collapse. One of the features that distinguishes the proposed performance is its development in the load-demand space and its ability to answer questions such as: "can the system withstand a simultaneous increase of 70 MW on bus 2 and 50 MVAr on bus 6?" This feature makes the performance index readily interpretable to operators. Moreover, the computation involved in the proposed performance index is relatively inexpensive in comparison with those required in existing solutions. Simulation results on the IEEE 39-bus system and a 234-bus power system are presented with promising results. >

Patent
23 Jan 1995
TL;DR: In this article, an integrated power system includes an engine/generator power supply integrated with storage batteries to provide household-like AC power, where the engine speed is variable for various loads.
Abstract: An integrated power system includes an engine/generator power supply integrated with storage batteries to provide household-like AC power. For a small load demand, the storage batteries are used to provide electricity. For a large load demand, the engine/generator starts to supply electricity. The engine/generator also recharges the storage batteries if the load demand is smaller than the engine/generator maximum load capacity. For a larger load demand, both the engine/generator and the storage batteries supply electricity in parallel. The engine speed is variable for various loads. The bigger the load, the higher the engine speed is required to produce the necessary power and keep a constant high DC voltage.

Proceedings ArticleDOI
18 Jun 1995
TL;DR: In this paper, the authors present the design guidelines and the results of a comparative study of power converters for AC power conditioning applications, including buck, boost, buck-boost, and Cuk.
Abstract: Recently a new family of AC-AC power converters has been proposed for AC power conditioning. They are solid state functional equivalents of transformers with a continuously variable transformation ratio. Operating on the principle of pulse width modulated control using gate turn off devices like IGBTs, they have been shown to have significant performance advantages compared to older generation thyristor based phase controlled power converters. The family of proposed converters include buck, boost, buck-boost and Cuk power converters. This paper is aimed at presenting the design guidelines and the results of a comparative study of these power converters. Detailed design equations are provided along with a typical examples of design of various power converters for a power conditioning application. >

Patent
06 Feb 1995
TL;DR: In this article, a motor control apparatus and method for controlling a multiphase AC motor by controlling electrical quantities such as voltage or current applied to the stator of the motor is described.
Abstract: A motor control apparatus and method is disclosed for controlling a multiphase AC motor by controlling electrical quantities such as voltage or current applied to the stator of the motor. The apparatus includes a motor command unit for defining a reference signal indicative of a desired motor parameter such as torque, speed, or position, a DC voltage link, a controller, a line-side converter including active switches in a bridge configuration for controlling the bidirectional flow of electrical power between the DC voltage link and a source of AC power, and a motor-side converter including active switches in a bridge configuration for controlling stator electrical quantities by controlling the bidirectional flow of electrical power between the DC voltage link and the motor, where the motor-side converter includes control means responsive to the reference signal for controlling the active switches to produce stator electrical quantities that correspond to the reference signal.