T.A. Lipo

University of Wisconsin–Madison | UW · Wisconsin Electric Machines and Power Electronics Consortium (WEMPEC)

Harmonic excitation brushless synchronous machine has higher power density compared with the traditional aerial three-stage generator due to removing the axial exciter and is suitable for using as an Integrated Starting-Generator (ISG). However, the field current can not be always generated in the field windings at different rotor positions in the...

This paper presents the design and optimization of a novel wound field synchronous machine topology, in which permanent magnets (PMs) are introduced into the rotor slot opening with segment configuration for high quality output torque performance. The rotor shape of the proposed PM-assisted wound field synchronous machine with segment configuration...

Abstract—High inertial loads are abundant in the industry and most of them are direct on line starter type induction machines with double cage rotors. Due to their higher starting time higher power dissipation in the rotor makes the rotor wear out and eventually gets destroyed. A new starting method proposed herein makes the motor start quickly and...

The paper proposes a fault-tolerant control strategy for a two-phase permanent magnet synchronous motor (PMSM) by a structural alteration. Firstly, a two-phase PMSM is designed with a structure of combination with two conventional single-phase U-core PMSMs. Each has a self-start ability because of the step air gap design on the inner side of stator...

This paper proposes a novel double-stator axial-flux spoke-type permanent magnet vernier machine, which has a high torque density feature as well as a high-power factor at low speed for direct-drive systems. The operation principle and basic design procedure of the proposed machine are presented and discussed. The 3-D finite element method (3-D-FEM...

Most industrial facilities involve use of various types of auxiliary loads in addition to a main sensitive load. Each of these loads are generally accompanied by load transformers. As these auxiliary loads are switched-in, their transformers also become energized. An inrush current often develops when the transformer is switched-in. This paper prop...

Numerous sensitive loads of commercial, industrial and domestic use depend upon an uninterruptible power supply (UPS) system to ensure uninterrupted, reliable, and high quality power during outages as well as over voltage and under voltage conditions to maintain healthy operation. In case of a power failure or other disturbance, a UPS system genera...

This paper proposes a novel dual stator axial flux spoke-type permanent magnet (DSAFSPM) machine for the purpose of improving torque (power) density and reducing cogging torque and torque ripple. This machine adopts low cost ferrite permanent magnets inserted into the rotor as a spoke-type array. Two stators with the same slot/teeth construction ar...

Matrix converter is a direct AC-AC converter which can convert AC power supply of a fixed voltage into an AC voltage of variable frequency and magnitude. It has a simple structure with several advantages over conventional converters. This paper proposes a novel SCR-IGBT based dual bridge matrix converter topology with reduced number of switches usi...

In this paper, coupling between active and reactive powers in conventional direct power control (DPC) strategies is analyzed and a new direct DPC method for doubly fed induction machine without rotor position sensors is presented. Coupling analysis is done on an improved DPC strategy with rotor flux controllers in the stator reference frame. The pr...

A versatile doubly-fed linear generator was recently presented for application in the point absorber ocean wave energy converter (WEC). While this machine may be operated as a singly- or doubly-fed induction machine or via a self- synchronous approach, operation as a synchronous machine is found to be an attractive method for experimental testing....

This paper proposes a grid-connected to rotor type doubly fed induction generator (DFIG) in which the rotor winding is connected to the grid instead of the stator winding. The stator size and weight of the proposed grid-connected to rotor type DFIG can be reduced because the proposed type can use rotor core more efficiently compared to the stator t...

This paper analyzes the insulated gate bipolar transistor (IGBT) power cycling capability for a dual-bridge matrix converter (DBMC) used as a motor drive and compares the result with the traditional dc/ac inverter and the conventional matrix converter (CMC). Two pulsewidth modulation (PWM) control methods for the DBMC are investigated. One is calle...

A versatile doubly-fed linear generator was recently presented for application in the point absorber ocean wave energy converter (WEC). Although the machine may be operated as a classical synchronous machine, or as a singly- or doubly-fed induction machine, a self-synchronous approach to operating the machine is found to be attractive in low speed,...

The configuration and control of a dual-half-controlled-converter (DHCC) designed for a permanent magnet synchronous generator (PMSG) wind turbine are proposed in this paper. The system performance is analyzed using Saber simulations. The simulations results demonstrate that by using coordinated current regulation techniques, pure sinusoidal input...

New observer-based disturbance-estimation and control algorithms are introduced in this paper that compensate source voltage unbalances. The algorithms are also designed to compensate the detrimental impact of delay effects caused by the digital-signal processing. Consequently, these techniques are appropriate for higher power systems with reduced...

Active rectifiers using pulsewidth-modulation voltage-source converters are popular choices for adjustable-speed drives to provide high input power quality. However, input current harmonics are often generated as a result of input voltage source disturbances. Since the frequencies of the fifth-, seventh-, and higher-order harmonics can easily excee...

This paper presents the design, analysis, control, and experimental evaluation of an innovative field-controlled axial-flux surface-mounted permanent-magnet machine. Topology and design equations, as well as an optimized design study, are attained. The machine is investigated in detail using finite-element analysis, and a prototype machine is built...

In this paper, computationally efficient sinusoidal-disturbance estimation and elimination methods are introduced into the control of an active front end (AFE) voltage-source converter (VSC) to achieve effective disturbance rejection in high power systems with slower pulsewidth-modulation switching frequencies (e.g., 5 kHz) and limited current-cont...

Doubly-Fed Induction Generators (DFIGs) are widely used for modern wind turbines. Although the stator winding of DFIG is directly connected to a grid while a rotor winding is connected to converters, it has a large outer size because of the high current in the stator winding. This paper proposes a grid-connected to a rotor type DFIG where rotor win...

Current regulation plays an important role in modern power electronic AC conversion systems. The most direct strategy to regulate such currents is to use a simple closed loop proportional-integral (PI) regulator, which has no theoretical stability limits as the proportional and integral gains are increased, since it is only a second order system. H...

This paper analyzes the IGBT power cycling capability for dual bridge matrix converter (DBMC) used as a motor drive and compares the result with the traditional DC/AC inverter and the conventional matrix converter (CMC). Two PWM control methods for the DBMC are investigated. One is called zero current switching PWM (ZCPWM) that allows zero current...

This paper develops an analytical model for a novel double-sided hybrid transverse/longitudinal flux linear machine for use in ocean wave energy converter (WEC) applications. While several machine topologies exist for direct-drive power take-off in buoy-type WECs, the intent of this paper is to introduce a new type of linear machine for possible us...

When a Halbach rotor is simultaneously rotated and translationally moved above a split-sheet aluminum guideway a traveling time-varying magnetic field is created in the air gap. This field induces eddy currents in the guideway that can simultaneously create suspension and propulsion forces. If the rotor is offset from the center then a re-centering...

This paper analyzes the power-cycling capability of insulated-gate bipolar transistor (IGBT) modules in a conventional matrix converter used as a motor drive. The analysis is made under various conditions for this topology, including low-speed-operation capability, high-speed thermal- and power-cycling capabilities, etc. It was found that the power...

We present an analytical method for the calculation of electromagnetic torque in surface permanent-magnet (PM) motors. Our method uses conformal mapping to calculate the electromagnetic torque by integrating the Maxwell stress tensor inside the air gap. It uses the radial and tangential components of the flux density in the slotted air-gap produced...

Doubly fed induction generators are presently used in the large majority of high power wind turbine applications. The present technology specifies that the turbine operate subsynchronously to follow the desired power vs. wind speed profile and to operate only supersynchronously during brief periods where wind gusts exceed the nominal maximum value...

This paper describes the use of vector space decomposition for development of a simplified model of a nine phase synchronous machine. It is shown that the nine phase machine can be reduced to the usual d-q equivalent circuit model plus seven additional circuits to represent zero sequence components. These additional components are shown to provide...

Modular permanent magnet machines are gaining popularity due to their simple stator construction and machine winding fabrication. In this paper, a multiphase modular permanent magnet machine is proposed to obtain a robust drive system with the feature of fault tolerant capability. By making use of concentric winding on each module, the stator windi...

In this paper, computationally-efficient sinusoidal disturbance estimation and elimination methods are introduced into the control of an active front end (AFE) voltage-source converter (VSC) to achieve effective disturbance rejection in high-power systems with slower PWM switching frequencies (e.g., 5 kHz) and limited current controller bandwidth....

This paper deals with the skew effects on starting characteristics of a line-start permanent-magnet motor (LSPM). Considering structural constraints of a rotor of an LSPM, we propose a stator-skewed core. With variation of the skew angle of stator core, the back EMF and the start-up characteristics are analyzed, and the optimal angle to maximize th...

Unbalanced input voltages can degrade the performance of voltage-source converters (VSC) by injecting a second harmonic voltage component onto the dc link voltage (120 Hz for 60 Hz system) that reduces the dc link capacitor lifetime and disturbs the performance of the attached inverter load. These negative effects can be eliminated if the voltage-s...

The paper presents a current-source inverter topology tailored for large multi-megawatt wind turbines. The proposed topology can inherently benefit from the distance between the generator and the mains because the consequent length and possible layout of the power cables may enable the realization of a significant portion of the dc-link inductance....

We present a two-dimensional complex steady-state finite-element method for calculating the lift and thrust or breaking forces created when a magnetic rotor is translationally moved and rotated over a conducting sheet. The method replaces the magnetic rotor with an equivalent current sheet by equating the current sheet's and magnet rotor's magnetic...

When a magnetic rotor is both rotated and translationally moved above a conductive, nonmagnetic, guideway eddy currents are induced that can simultaneously create lift, thrust, and lateral forces. In order to model these forces, a 3D finite-element model with a magnetic charge boundary has been created. The modeling of the rotational motion of magn...

We present an analytical method for the calculation of cogging torque in surface permanent-magnet (PM) motors. The cogging torque is calculated by integrating the Maxwell stress tensor inside the air gap. The principle of complex relative air-gap permeance derived from conformal transformation of the slot geometry is used to take into account the e...

This paper proposes a circuital solution, aimed at a class of current-source inverter topologies, that provides the ability to ride-through temporary low voltage, as well as open circuit conditions at the mains without opening the mains circuit breakers. Although the proposed solution has broader applications, it is described in the framework of a...

Multilevel converters use series/parallelled semiconductor switching devices to synthesise switched waveforms at power levels that are well above individual device ratings. To date, most multilevel inverter research has focused on voltage source structures, primarily because these topologies address the more common high power converter limiting fac...

The mechanical rotation of a radially positioned permanent-magnet Halbach array above a conducting, nonmagnetic track induces eddy currents in the track that can inductively create suspension and propulsion forces simultaneously. The parameters that affect the performance of this electrodynamic wheel are studied using a 2-D steady-state finite-elem...

This paper presents a current-source inverter topology that is suitable for multi-megawatt wind turbines. The proposed scheme utilizes two series-connected three-phase inverters that employ fully controllable switches and a proper interconnection transformer with the mains. In order to improve the efficiency and to allow the use of high-power devic...

Modular permanent magnet machines are gaining popularity for their ease in assembling the stator pieces and phase windings. In this paper, a multiphase modular permanent magnet machine with a corresponding drive topology is proposed as a high performance drive system. The machine stator modules are fabricated by soft magnetic composite (SMC) materi...

Bearing currents have been identified as a major cause of electrical machine failure when operating from a solid-state pulse-width modulated inverter. This is because at frequencies corresponding to the switching time of the inverter semiconductors, charges accumulating in the parasitic capacitances between the stator and rotor create voltages acro...

The paper presents a current-source inverter topology conceived for multi-megawatt wind turbines. The proposed scheme utilizes two series-connected three-phase inverters employing fully controllable switches and a proper interconnection transformer with the mains. In order to improve the efficiency and allow the use of high power devices, the inver...

The complexity of the permanent magnet (PM) machine structure makes the optimal design of the PM machine always a difficult task. The multiple objectives of an optimal design make most classic optimization algorithms inapplicable, due to the nonlinearity and some discontinous variables. In this paper, two interior permanent magnet (IPM) machine des...

Voltage unbalance or sag conditions generated by the line excitation can cause the input rectifier stage of an adjustable-speed drive (ASD) to enter a single-phase rectifier operation. This degradation of the input power quality can have a significant negative impact on the induction machine performance characteristics, but the presence of an LC fi...

We present an analytical method for calculation of no-load magnetic field distribution in the slotted air gap of a surface permanent-magnet (PM) motor with radial or parallel magnetization. The method introduces the notion of complex relative air-gap permeance, calculated from the conformal transformation of the slot geometry, to take into account...

This paper proposes a new definition of instantaneous reactive power in the complex synchronous rotating frame and control scheme under unbalanced networks. The mathematical model of instantaneous active and reactive power has been derived for a pulsewidth-modulated (pwm) ac/dc converter under generalized unbalanced operating conditions. Based on t...

In this paper, pulsating torque components of permanent magnet machines and pulsating torque minimization techniques are discussed for axial flux surface-magnet disc-type PM machines. The pulsating torque analysis describing general instantaneous electromagnetic torque equation and torque ripple factor is briefly provided in order to analyze torque...

The rotation of radial positioned magnets over a thin aluminum sheet or ladder guideway induces currents in the guideway that can simultaneously create thrust and lift forces. The uses of a flat split-guideway topology can also generate guidance forces when offset from the center. The magnetic rotor that creates these forces has been termed an elec...

Standard low- and medium-power drives are based on the voltage-source converter topology. There has been less research work on dual topology drives, based on a current-fed inverter structure. Although energy storage is more efficient in capacitors than in inductors, due to some inherent advantages of current-source converter topology, and at the fi...

This paper proposes a new control scheme of improved transient response for the pulsewidth-modulation ac/dc converter under generalized unbalanced operating conditions. The overall-bandwidth diminishing filter/functional block for extracting positive and negative sequence components has been avoided by employing dual current regulators in positive-...

Voltage unbalance or sag conditions generated by the line excitation can cause the input rectifier stage of an adjustable-speed drive (ASD) to enter single-phase rectifier operation. This degradation of the input power quality can have a significant negative impact on the induction-machine performance characteristics. This paper provides an approxi...

This paper proposes a control method to the magnet flux in an interior permanent-magnet (IPM) motor following short-circuit-type faults in either the inverter drive or motor stator windings. Phase-based control is employed to implement the flux-ing-control method so that it is possible to take advantage of a zero-sequence current in order to minimi...

This paper proposes a fully passive protection scheme for DC link inductors whose geometry is characterized by a substantial distance between the rectifier and inverter stations. Inductors of this type can be found intrinsically in very long high-power cables-as in HVDC transmission for example-as well as in DC-links for high-power current source i...

This paper investigates the impact of input voltage unbalance and sags on stresses in the dc bus choke inductor and dc bus electrolytic capacitors of adjustable-speed drives (ASDs). These stresses are primarily attributable to the rectifier's transition into single-phase operation, giving rise to low-order harmonic voltages (120 Hz, 240 Hz, etc.) t...

A double side converter fed wound rotor induction machine control for a wind energy application is proposed in this paper. In order to reduce the cost of a wind generator system, a new configuration using half controlled converters for both the stator and rotor circuit as well as for the line side is proposed. The proposed controller reduces the re...

With the improvement of soft magnetic composite (SMC) material, electric machine design is no longer limited to the traditional iron lamination technology. The single extrusion fabrication process of the SMC material simplifies construction of machine armature core. Moreover, the isotropic material property can be exploited for various machine stru...

Most small induction motors in current use employ concentric windings which have equal numbers of turns per coil. An optimal choice of turns can achieve better distribution of MMF in the gap while keeping the turns in each slot essentially the same. In this paper, the air gap magnetic motive force (MMF) harmonics of electrical machine created by th...

This paper describes an overview of the ongoing work at the University of Wisconsin concerned with power electronics and electric machinery as related to next generation ship propulsion and aircraft launch. While more than a half dozen projects have been completed for the naval applications in recent years, three topics have been selected to illust...

Filter networks for long cable drives have been studied in the last decade to solve the overvoltage problem at the motor terminals. However, little research has been dedicated to analyze their influence on the voltage distribution in the motor stator winding and on the circulation of the common-mode currents. In this paper, the project of dv/dt fil...

Direct line starting of induction machines causes high torque transients and inrush currents that can be attenuated using soft starters that adjust the applied stator voltage amplitude. Startup performance of the induction machine with a soft starter and gamma control strategy can be predicted much more accurately when deep bar effect is incorporat...

Cascaded multilevel inverters can be implemented through the series connection of single-phase modular power bridges. This work presents details on how these bridges should be implemented and operated to synchronize their pulse-width-modulation (PWM) carriers, fundamental references and sampling instances to implement a network-controlled cascaded...

This paper describes a real time simulator of matrix converter system. The simulated plant is a classical matrix converter with source, input filter and load. The simulator is based on the RT-LAB real time simulation platform, which enables easy model-to-target designs from Simulink models. The simulator is designed to accept real IGBT/GTO/MOSFET f...

A multiobjective optimization procedure for the design of interior PM motors based on differential evolution algorithm is presented. A comparative analysis has been carried out for the optimized 5 kW, 50 kW and 200 kW IPM motors with two and three layers of cavities in the rotor to show design trade-offs between goals to minimize the motor volume w...

For years, design of conventional permanent magnet motors has been limited mainly to the variation of the stator winding function and little research has been made on stator pole modification as an alternative for motor design. Soft magnetic composites (SMCs) have opened up new possibilities for the 3-D pole shape design of both DC and AC machines...

This work investigates methods to interrupt the phase currents induced when interior permanent magnet (IPM) machine drives suffer short-circuit or uncontrolled generator mode faults. A fault-tolerant silicon switch is proposed in which the antiparallel diode in a reverse-blocking inverter switch is replaced by a thyristor. A reduced-parts-count fau...

This paper proposes a control method to the magnet flux in an interior permanent magnet (IPM) motor following short-circuit type faults in either the inverter drive or motor stator windings. Phase control is employed to implement the flux ing control method so that it is possible to take advantage of a zero sequence current in order to minimize the...

This work proposes a new control scheme of improved transient response for the PWM AC/DC converter under generalized unbalanced operating conditions. The overall bandwidth diminishing filter/functional block for extracting positive and negative sequence components have been avoided by employing dual current regulators in positive and negative rotat...

This paper compares the many fault tolerant three-phase ac motor drive topologies that have been proposed to provide output capacity for the inverter faults of switch short or open-circuits, phase-leg short-circuits, and single-phase open-circuits. Also included is a review of the respective control methods for fault tolerant inverters including tw...

This paper proposes a new control scheme of improved transient response for the PWM AC/DC converter under generalized unbalanced operating conditions. The overall bandwidth diminishing filter/functional block for extracting positive and negative sequence components have been avoided by employing dual current regulators in positive and negative rota...

This paper characterizes six-leg inverters to mitigate short-circuit faults for interior permanent magnet (IPM) synchronous machines. Key differences between bus structures in six-leg inverters are identified. For six-leg inverters employing two isolated DC links, it is shown that up to 75% of rated output power could be produced following a single...

This paper proposes operating a three-level neutral-point-clamped (NPC) inverter using a two-level pulsewidth-modulation method. This allows for the clamping diodes to be rated at a fraction of the main switches due to their low average current requirement. The use of a bootstrap charge pump as a low-cost method to obtain the isolated gate drive po...

A novel machine family-the dual-rotor, radial-flux, toroidally wound, permanent-magnet (RFTPM) machine-has been proven in a previous paper to be able to improve the machine efficiency and boost the torque density. This paper will present the key design equations and design procedure of the RFTPM machines, analyze parameter effects on machine perfor...

Electrolytic capacitors are used in nearly all adjustable-speed drives, and they are one of the components most prone to failure. The main failure mechanisms include loss of electrolyte through outgassing and chemical changes to the electrolyte and oxide layer. All the degradation mechanisms are exacerbated by ripple current heating. Since the equi...

High-temperature superconducting (HTS) material in bulk form is used to design a linear synchronous motor for an electromagnetic aircraft launch system. The motor is designed without an iron core. Stator coils are placed in the air while the permanent magnets used in conventional design of linear permanent magnet synchronous motors are replaced by...

In this paper the magnetic characteristics of surface-mounted permanent-magnet machines are analyzed and modeled. The air-gap and zigzag leakage fluxes are analytically expressed in terms of the magnetic material properties and the motor dimensions. Both factors are essential quantities for the accurate prediction of the flux distribution within th...

This paper presents a new hysteresis current regulation technique with reduced common mode switching for three-phase multilevel inverters. The proposed technique uses three independent multilevel hysteresis current regulators to generate three sets of complementary gating signals through the comparison of the measured current errors with implemente...

The paper presents a current-source inverter (CSI) topology tailored for large multi-megawatt wind turbine applications. The cable distance between the generator and the mains enables the realization of a significant portion of the DC-link inductance. In order to improve the efficiency and to allow the possible utilization of rugged inexpensive thy...

Axial flux permanent magnet (PM) machines are being developed for many applications due to their attractive features. An extensive literature exists concerning the design of a variety of types of axial flux PM machines. An overview of axial flux, slotless and slotted various PM machines are presented in this paper. Machine structures, advantages an...

The paper addresses the topic of the harmonic reduction and fundamental power factor correction for three-phase current-source (CS) DC-AC converters in a unified mathematical manner. Starting only from the analytical definition of the power characterizing the line current error signal, a closed-loop general optimal control strategy is deduced valid...

Filter networks for long cable drives have been studied in the last decade to solve the over-voltage problem at the motor terminals. However, little research has been dedicated to analyze their influence on the voltage distribution in the motor stator winding and on the circulation of the common-mode currents. In this paper, the project of dv/dt fi...

This paper investigates the performance of a dual-bridge matrix converter (DBMC) operating with distorted source voltages. A direct feed-forward unbalance control scheme is developed to reduce the influence of input voltage distortion to the load. The line side source voltages and its fundamental component are first detected. Then, appropriate dist...

A novel machine family-dual-rotor, radial-flux, toroidally wound, permanent-magnet (RFTPM) machines-is proposed in order to substantially improve machine torque density and efficiency. After the principles of operation, configurations, and features are discussed, the machine design and optimization guidelines are given. A prototype has been designe...

In this paper a description and operating principles of a consequent-pole permanent-magnet machine are presented. In addition, a sizing analysis, finite-element analysis, and experimental results for a prototype machine are addressed. Due to its particular configuration, this machine allows for a wide range of control of the air-gap flux with minim...

A variety of techniques exist for reducing the cogging torque of conventional radial flux PM machines. Even though some of these techniques can be applied to axial flux machines, manufacturing cost is especially high due to the unique construction of the axial flux machine stator. Consequently, new low cost techniques are desirable for use with axi...

The dual-bridge matrix converter (DBMC) concept has been gaining recognition as a promising circuit alternative. Among all the DBMC topologies with reduced number of switches, the 9-switch topology shows the least number of switches and high quality waveforms. However, it has been proven that this converter can not operate safely when the output po...

First Page of the Article

This paper presents modulation strategies for cascaded multilevel inverters that substantially eliminate common-mode voltage on the output phases. The paper begins by developing generic multilevel inverter reference waveforms that use only "allowed" space vectors to achieve reduced common-mode voltage. A graphical technique is then proposed that al...

This paper presents a novel method for measuring the magnetizing inductance of an induction machine. The approach uses a static DC excitation technique which can be employed whenever the neutral of the machine is accessible. The proposed method measures only the magnetizing inductance and not the self inductance which normally includes the effect o...

The dual-bridge matrix converter concept has been gaining recognition as a promising circuit alternative in recent years. A direct feed-forward unbalance control method with power factor adjustment ability is developed for a 9-switch dual-bridge matrix converter system. It firstly detects the line side source voltages. Then, after adjusting the swi...

An improved 3-phase isolated controlled rectifier with unity power factor interface and sinusoidal current waveforms is proposed in this paper. The power ratings of the active devices are reduced to half the rated power of the rectifier. The proposed rectifier consists of two complementary isolated half controlled circuits connected to a common DC...

The three-phase AC-AC converter termed the matrix converter can provide high quality input/output waveforms and adjustable input power factor without any large energy storage component. However, it has not yet found much acceptance in industry. The main reason is that it requires a complicated commutation scheme to prevent input side short circuits...

Cascaded multilevel inverters can be implemented using single-phase modular power bridges, each having their own DSP processor and associated control circuitry. This paper presents details of how these bridges should be operated to synchronise their PWM carriers and fundamental references to implement a cascaded inverter with distributed PWM comput...

In this paper, the sizing equation analyses are presented for two different radial and axial flux field controlled PM machines. These types of machines have two sources of excitation which allows one to easily control the airgap flux. Variable flux component provided by the field winding and fixed flux component obtained from PM converge into the a...

In this paper, the concept of "smart motor" or motor-controller integration is proposed and hardware setup is also presented. This paper compares possible topologies for single phase permanent-split-capacitor induction motor adjustable speed drive from the aspects of number of inverter legs, minimum DC bus voltage requirement and DC bus current RMS...

A reduced switch count double side converter fed wound rotor induction machine control for a wind energy application is proposed in this paper. The outputs of two converters are combined electromechanically in the machine and are capable of sharing the power equally both from stator and rotor simultaneously. In order to reduce the cost a new config...