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The high-frequency common-mode voltage introduced by power converters, using conventional modulation techniques, results in common-mode current that has the potential to cause physical damage to the shaft and bearings of electric drives as well as unwanted tripping of ground fault relays in motor drives and electrical networks. The paper aims to provide a complete elimination of common mode voltage using a matrix converter (MC) with a new modulation strategy that reduces the size of the power converter system considerably. Further, a new MC topology is proposed to eliminate the common mode voltage with improved voltage transfer ratio (VTR).

The direct MC topology is selected, as it is the only converter topology that has the potential to eliminate common mode voltage in direct AC to AC systems. Using the rotating space vector technique, common mode voltage is eliminated but this reduces the VTR of the converter. To improve the VTR, a modified MC topology with a modified rotating space vector strategy is proposed. In addition, for improving the power factor at the input, the input current control strategy is developed.

The use of rotating space vector technique eliminates the common mode voltage even under all input abnormalities like unbalance and harmonics. By applying positive and negative rotating space vectors, input power factor control can be achieved. However, the control range is limited from unity power factor to the output power factor. It is observed that in the current controlled technique the modulation index reduces further. It is also found that there is a reduction in switching stresses of individual switches in proposed topology compared to direct MC topology.

In this paper, a modified rotating space vector technique is applied to the proposed converter topology for elimination of common mode voltage with an increased VTR. The topology can be used for common mode voltage elimination in existing electric drives without the need for modifying the drive system.

This paper aims to present a modified space vector pulse width modulation (SVPWM) technique for six-phase induction motor drive based on common-mode voltage (CMV) and current losses which are two important issues affecting drive system behavior and quality.

It is shown that the presence of z-component currents and the presence of CMV in six-phase drive system are two major limiting factors in space vector selection. The behavior of several space vector selections in a two-level inverter considering minimum CMV and z-components is investigated. Then, the space vectors in a three-level inverter is analyzed and tried to explore an SVM technique with better behavior.

The analyses show that all the problems cannot be solved in a six-phase drive system with two-level inverter despite having 64 space vectors; this study tried to overcome the limitations by exploring space vectors in a three-level inverter.

The proposed pulse width modulation (PWM) strategy leads to minimum current distortion and undesired current components with zero CMV and modest torque ripple.

This paper aims to investigate the common-mode voltage (CMV) issue of a three-phase four-leg voltage-source inverter. A new space vector modulation method, named as three-dimensional active zero state Pulse-width modulation (PWM) (3-D AZSPWM), is proposed to reduce the CMV level.

PWM is a general method to generate the switching signals of the power converters in order to obtain high-quality output voltages. However, the CMV produced by PWM methods has become a serious problem. 3-D AZSPWM is proposed to solve this issue. In 3-D AZSPWM, instead of using zero voltage vectors with high CMV level, appropriate complementary non-zero vectors are introduced to synthesize reference vector. The proposed method is classified into four types of AZSPWM1(a), AZSPWM1(b), AZSPWM2(a) and AZSPWM2(b) based on different complementary vectors chosen for each type. An extend software simulation using MATLAB/Simulink is performed to verify the superior performance of the proposed methods.

Compared to other reduced CMV methods, the proposed method not only reduces the CMV but also retains the positive characteristics of the three-dimensional classical space vector PWM (3-D CSVPWM).

The proposed method does not suffer from linear modulation region limitation and also does not impose additional switching loss. Furthermore, calculated output voltage harmonic distortion factor illuminates acceptable quality of output voltage produced by the proposed method.

This paper presents analytical and experimental results that quantify the performance of an induction motor fed by a space‐vector pulse width modulated four‐switch (B4) voltage source inverter. First, as voltage vectors in the inverter form unsymmetrical sequences, the discrete Fourier transform is used to express the voltage vectors in symmetrical form. Second, by using a mixed p‐z approach for every voltage vector sequence, we can derive a closed‐form solution, including steady‐state and transient components of the motor currents. From the motor currents, we can derive an analytical equation for the electromagnetic torque. Both the steady‐state and transient components of the motor currents are determined in a simple and lucid analytical form, which avoids involved matrix inversion as well as exponentiation. The theoretical considerations are verified on an experimental unit.

To provide a new method and methodology for researches and academic members which can help them to develop scientific work.

The paper presents closed‐form expressions for the harmonic components of the space‐vector pulsewidth modulated (PWM) waveforms under inverter fault‐mode operations. The main method that is used is the Laplace transform and Fourier series expansion theorem.

Provides information about harmonic sources and its influence on the behavior of the induction machine.

The calculated harmonics show a very close agreement with measured harmonics from an experimental digital signal processor (DSP) based modulator. It provides a very useful source of theoretical and practical information for scientific and research area.

The method is original and has not been published before. The new and original approach is given by the use of the Laplace transform of space‐vectors in the complex plane. This will help to understand harmonics which are formed in four‐switch voltage source inverter.

The paper aims to discuss the comparison of the performance of four space‐vector pulse‐width modulation (SVPWM) strategies dedicated to four‐switch three‐phase inverters (FSTPI).

The comparison is based on three comparison criteria: the total harmonic distortion, the switching loss factor, and the quality factor. The comparison is extended to the FFT of the phase currents and to the analysis of the ripples of the electromagnetic torque of the induction motor.

It has been clearly shown that the basic SVPWM strategy of the conventional six‐switch three‐phase inverter (SSTPI) offers better performance than those of the four FSTPI‐SVPWM strategies. This said, it has been found that the performance of two among the four FSTPI‐SVPWM strategies tend to those of the SSTPI‐SVPWM basic strategy, especially in high switching frequencies.

The work should be extended by an experimental validation of the simulation results.

The established results open up crucial benefits from the point of view of cost‐effectiveness and volume‐compactness improvements of induction motor drives especially in large‐scale industries such as the automotive one where electric and hybrid propulsion systems are currently regarded as an interesting alternative to substitute or to assist the thermal propulsion systems.

The implementation in the FSTPI feeding an induction motor of SVPWM strategies exhibiting acceptable performance, which tend to those yielded by the SSTPI‐SVPWM basic strategy especially in high switching frequencies, is extended here.

The paper aims to propose a new type of three-phase quasi-Z-source indirect matrix converter (QZSIMC) to extend the voltage gain for application in the induction motor drives.

A unique H-shape quasi-Z-source network is connected between the three-phase voltage source and traditional indirect matrix converter to achieve the voltage boost and buck in a single-stage power conversion. The complete space vector modulation (SVM) method is proposed to control the proposed QZSIMC. The output voltage amplitude of quasi-Z-source network can be boosted by the shoot-through of the front-end rectifier, so the whole system's voltage gain is extended. Meanwhile, the QZSIMC modeling and quasi-Z-source impedance parameter design are developed by using the state space averaging method. The design-oriented analysis based on small signal model is used to investigate the quasi-Z-source impedance parameter's impact on the QZSIMC's dynamic performance. A simulated application example employs a 4-kW induction motor drive to verify the proposed QZSIMC, the developed modulation method and parameter design method.

The proposed QZSIMC can achieve high voltage gain larger than one and also can fulfill buck function, which widens the induction motor drive's operation range. The simulation results verify the proposed QZSIMC and SVM and also validate the quality performance of the proposed induction motor drive and all theoretical analysis and parameter design method.

The proposed QZSIMC effectively overcomes the limitation of traditional indirect matrix converter, through extending the voltage gain larger than one. The systematic principle, analysis, parameter design, and simulation verification provide the proposed QZSIMC with a feasible approach in practical induction motor drive applications.

Five-level rectifiers have received widespread attention because of their excellent performance in high-voltage and high-power applications. Taking a five-level rectifier with only four-IGBT for this study, a sliding mode predictive control (SMPC) algorithm is proposed to solve the problem of poor dynamic performance and poor anti-disturbance ability under the traditional model predictive control with the PI outer loop.

First, mathematical models under the two-phase stationary coordinate system and two-phase synchronous rotating coordinate system are established. Then, the design of the outer-loop sliding mode controller is completed by establishing the sliding mode surface and design approach rate. The design of the inner-loop model predictive controller was completed by discretizing the mathematical model equations. The modulation part uses a space vector modulation technique to generate the PWM wave.

The sliding mode predictive control strategy is compared with the control strategy with a PI outer loop and a model predictive inner loop. The proposed control strategy has a faster dynamic response and stronger anti-interference ability.

For the five-level rectifier, the advantages of fast dynamic influence and parameter insensitivity of sliding mode control are used in the voltage outer loop to replace the traditional PI control, and which is integrated with the model predictive control used in the current inner loop to form a novel control strategy with a faster dynamic response and stronger immunity to disturbances. This novel strategy is called sliding mode predictive control (SMC).

The purpose of this paper is to propose a new method that allows to compare the magnetic pressures of different pulse width modulation (PWM) strategies in a fast and efficient way.

The voltage harmonics are determined using the double Fourier integral. As for current harmonics and waveforms, a new generic model based on the Park transformation and a dq model of the machine was established taking saturation into consideration. The obtained analytical waveforms are then injected into a finite element software to compute magnetic pressures using nodal forces.

The overall proposed method allows to accelerate the calculations and the comparison of different PWM strategies and operating points as an analytical model is used to generate current waveforms.

While the analytical expressions of voltage harmonics are already provided in the literature for the space vector pulse width modulation, they had to be calculated for the discontinuous pulse width modulation. In this paper, the obtained expressions are provided. For current harmonics, different models based on a linear and a nonlinear model of the machine are presented in the referenced papers; however, these models are not generic and are limited to the second range of harmonics (two times the switching frequency). A new generic model is then established and used in this paper after being validated experimentally. And finally, the direct injection of analytical current waveforms in a finite element software to perform any magnetic computation is very efficient.

The purpose of this paper is to describe a new method for sensorless hysteresis direct torque control (HDTC) algorithm for permanent magnet synchronous motor to minimize torque ripple and electromagnetic interference (EMI) noises.

The design methodology is based on space vector modulation of electrical machines with digital vector control. MATLAB simulations supported with experimental study under C++ are used.

The simulation and experimental results of this proposed algorithm show adequate dynamic torque performance and considerable torque ripples reduction as well as lower current ripples, lower EMI noise level as compared to traditional HDTC.

This research is limited to PMSM, however the research can be extended to include induction motor as well. In addition, the actual mathematical relation between the torque ripple and flux ripple can be studied to set the flux and torque bands width in reasonable value, and this relationship can be used to select switching time of the active selected vectors.

The implementation of the proposed algorithm in microcontroller embedded systems is described. It requires no PI controller in the torque control loop In addition, based on existence direct torque control equipment, it is only required to change the software switching algorithm, to provide smooth torque, given that the switching frequency of the inverter module is more than or equal to 15 kHz and the system is supplied with timers.

The algorithm used in this work utilizes the output of two hysteresis controllers used in the traditional HDTC to determine two adjacent switching vectors per one sample time. The algorithm also uses the magnitude of the torque error, magnitude of the flux error and stator flux position to select the switching time for the selected vectors to control the applied average voltage level in such a way that the torque ripple is minimized. The selection of the switching time of the selected active vectors utilizes novel table structure which reduces the complexity of calculation. This work is directed to designers of ac motor drive system who seek smooth torque performance as well as low EMI noise level.