Five-phase Voltage Source Inverter Research Articles

A Comprehensive Review on Comparison and Performance of Five-Phase Space Vector Pulse Width Modulation Overmodulation Strategies

High-performance overmodulation strategies for voltage source inverters (VSIs) can further broaden the operation range of machines. Among them, Space Vector Pulse Width Modulation (SVPWM) is worth researching as it performs well in digital implementation. This paper presents a detailed comparison of various SVPWM overmodulation strategies and analysis of their performance. It firstly briefly elaborates fundamental laws of two subspaces of five-phase VSIs. Then, it focuses on several overmodulation strategies. Their corresponding basic principles and main characteristics are researched, and conclusions are given. In addition, differences and relationships between them are proved and summarized. Lastly, comparative simulations and experiments were carried out and verify that in the overmodulation region, the output voltage distortion degree increases with the increase in modulation ratio, and strategies with more control degrees of freedom (CDFs) are capable of better controlling the third harmonic subspace, which means that higher-quality output voltage waveforms would be obtained.

Five-phase induction motor drive-A comprehensive review

Modern Electrical Vehicles (EV) and Electric Traction rely heavily on electrical drives. Every day, electric vehicles are being improved and expanded to include commercial vehicles such as passenger vehicles, goods delivery vehicles, and agricultural vehicles. Today, researchers are concentrating on multi-phase electrical drives to improve EV technology. This article provides a comprehensive analysis of the Five-Phase Induction Motor (FPIM) drive. The proposed study investigates the FPIM drive in terms of mathematical modeling and design, the different topologies of a Five-Phase Voltage Source Inverter (FPVSI) (Two-Level, Multi-Level, Matrix), the methodologies utilised to generate the pulse for FPVSI (Carrier-Based Pulse Width Modulation (CBPWM), Space Vector Pulse Width Modulation (SVPWM)), and the control of FPIM. This study evaluates the many strategies available in the literature for controlling the FPIM in order to assist researchers and industrial Research and Development (R&D) engineers in selecting the most suitable tool for their applications.

Comparison of SVPWM Techniques Under Switching Loss Control for Induction Motor Drive With LC Filters

Only precise industrial applications can benefit from the high-frequency performance of variable-speed drives with low switching losses. A five-phase induction motor (FPIM) is connected to a voltage source inverter (VSI) via a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$LC$</tex-math></inline-formula> filter (low pass filter) to reduce high-frequency losses in the motor. A five-phase sinusoidal voltage is used to lower the high <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$dv/dt$</tex-math></inline-formula> at the motor terminals. However, sustained resonant frequency oscillations destabilize closed-loop control of the FPIM drive at certain operational points. This paper presents and analyzes a variety of high-frequency SVPWM techniques, both continuous and discontinuous. It is also possible to optimize the switching frequency of the five-phase two-level VSI fed FPIM drive using an improved current ripple prediction method. Auxiliary circuits and high-frequency sensors are not necessary in this system, making it more stable. Simulated and experimental results are used to evaluate the stability of a drive under a variety of conditions.

Common-Mode Voltage Mitigation Strategies Using Sigma–Delta Modulation in Five-Phase VSIs

Various sigma–delta ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\Sigma$</tex-math></inline-formula> <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\Delta$</tex-math></inline-formula> ) modulation techniques for reducing the maximum peak-to-peak amplitude of common-mode voltage (CMV) by 80% in a five-phase, high-frequency voltage source inverter (VSI) are proposed and evaluated in this article. These techniques are based on choosing a set of vectors that limits the CMV amplitude. Operating the VSI under high-frequency pulsewidth modulations (PWM) generates a large number of changes in the CMV levels, which leads to common-mode currents (CMCs) and conducted electromagnetic interferences (EMIs). The proposed modulation techniques achieve the following: 1) High-efficiency converter operation and output voltage with low total harmonic distortion (THD); 2) an 80% reduction in CMV peak-to-peak amplitude; 3) a decrease in the number of the CMV transitions, thus reducing the CMCs; and 4) a decrease in the conducted EMI amplitude. The use of single-loop and double-loop <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\Sigma$</tex-math></inline-formula> <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\Delta$</tex-math></inline-formula> modulators is analyzed by means of Matlab/Simulink and PLECS simulations. The implementation of the proposed modulation techniques has been experimentally evaluated using a five-phase VSI with silicon carbide semiconductors. In order to demonstrate the improved performance, the results obtained are compared with those of other PWM and space vector modulation techniques that also mitigate the CMV amplitude by 80% but lack the other improvements.

Hybridized Space-Vector Pulsewidth Modulation for Multiphase Two-Level Voltage Source Inverter

In space vector pulsewidth modulation (SVPWM) algorithms for multiphase two-level voltage source inverters (VSI), the components of active vectors in all orthogonal spaces have to be calculated within the processor and stored in its memory. These necessitate intensive computational efforts of the processor and large memory space. This article presents a hybridized SVPWM for multiphase two-level VSI. In this algorithm, elements of the vector coefficient inverse matrix are calculated once outside the inverter processor and treated as constant values; this reduces the computational efforts of the processor and memory space. This scheme reverses the computational steps used in classical SVPWM. Arbitrarily pre-selected active vectors (for any position and amplitude of the reference vectors) with durations determined using classical SVPWM concept are utilized. The durations of switching vectors are analyzed and the switching sequences in individual inverter phases are optimized to reduce the number of commutations. This approach demonstrates that resignation from classical analytical method in multiphase two-level VSI enables the creation of simplified modulation algorithm. This modulation strategy enables an independent generation of multiple output voltage vectors with independent rotating speed, lengths, and positions. Experimental validation of the algorithm was carried out on two-level five-phase VSI with <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RL</i> load.

Analytical Calculation of Harmonics and Harmonic Losses in Five-Phase Carrier-Based PWM Voltage Source Inverters

The main purpose of this paper is to analyze a five-phase Voltage Source Inverter (VSI) that is operated with the Pulse Width Modulation (PWM) switching technique. Double Fourier integral (DFI) analysis has been used to extract the harmonics of the line-to-line voltages. Moreover, the harmonic current ripple has been calculated for an effective inductive five-phase load with a regular pentagon connection. Correspondingly, a new closed-form solution for calculating the harmonic losses in five-phase VSIs has been derived. In addition, a new equation for the weighted total harmonic distortion (WTHD) index has been extracted for five-phase VSIs. To validate the suggested analytical solutions (i.e., harmonic losses and WTHD equations), the results are compared with the DFI calculation method and the method of applying the fast Fourier transform (FFT) to a simulated waveform. The results show that the proposed analytical method has high accuracy and requires less mathematical effort, especially at high-frequency ratio values. Finally, the study includes simulation results and the implementation of an experimental setup.

Simple MPCC Strategy for Three-Level Sparse Five-Phase VSI to Suppress Current Harmonics With Balanced Neutral-Point Voltage

This article introduces a simple model-predictive current control (MPCC) strategy for a three-level sparse five-phase voltage source inverter to suppress current harmonics and balance the neutral-point voltage. A total of 21 new virtual voltage vectors were developed as the control set of the MPCC, and an optimal voltage vector is selected among these 21 virtual voltage vectors to suppress output current harmonics. Since the switching states from the optimal voltage vector are determined according to the difference between the upper capacitor voltage and the lower capacitor voltage, the proposed MPCC guarantees the balanced neutral-point voltage without weighting factors and capacitor voltages prediction. Therefore, the proposed MPCC strategy can be implemented simply, and the computing time is significantly reduced. Simulation and experimental results are provided to verify the validity of the proposed strategy.

Comparative analysis of 3D‐SVM and 4D‐SVM for five ‐phase voltage source inverter

Pulse width modulation (PWM) methods play a major role to control the various power electronic converters to progress the recital of the system. In this paper, a comparative analysis is done for three dimensional space vector modulation (3D-SVM) and four dimensional space vector modulation (4D-SVM) for five-phase voltage source inverter. 3D-SVM method comprises all qualities of conventional SVM; switching time calculation is simple and much suitable for three-phase system; where in five-phase system, it has redundant switching state vectors. 4D-SVM includes advantages of 3D-SVM and other conventional methods, it employs only nonredundant switching state vectors; it directs to diminish the intricacy in switching time calculations and avoids trigonometric calculations and look up tables for reference vector identification. The various parameters such as total harmonic distortion, improved output voltage, minimized common mode voltage and switching time calculation are analyzed and compared for 3D-SVM and 4D-SVM techniques. Simulation and hardware results are acquired and established using matlab simulink and FPGA processor, respectively.

Virtual Voltage Vector-Based Model Predictive Current Control for Five-Phase VSIs With Common-Mode Voltage Reduction

Model predictive current control (MPCC) schemes have been considered as a promising control technique for voltage source inverters (VSIs). However, the computational burden reduction, harmonic currents elimination, and common-mode voltage (CMV) mitigation are special issues when MPCC schemes are applied to five-phase VSIs. Moreover, it is time-consuming to tune weighting factors for the multiple control objectives. To address these problems, this article proposes two computationally efficient MPCC schemes based on virtual voltage vectors ( V <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> s), named MPCC-V <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> -RCMV1 and MPCC-V <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> -RCMV2. The former one achieves lower harmonics, whereas the latter one achieves lower switching frequency. The V <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> s are defined with basic voltage vectors that generate small CMV; hence, inherent CMV reduction can be achieved. The proposed MPCC schemes simplify the controller by redefining the cost function and control set, which reduces the computational effort significantly. Besides, the proposed MPCCs can improve the quality of current waveforms. Simulations and experiments are carried out to verify the effectiveness of the proposed control schemes.

Pulse Width Modulation Technique for Multilevel Operation of Five-Phase Dual Voltage Source Inverters

To supply five-phase variable speed drives, five-phase voltage source inverters are used. Some of the applications of five-phase variable speed drives are traction, electric &amp; hybrid-electric vehicles, and ship propulsion. Different control systems are available for the controlled output of the five-phase VSI, but space vector pulse width modulation is popular because of its simpler digital implementation. In this paper, the SVPWM schemes have proposed and analyzed for the multilevel operation of a five-phase dual voltage source inverter. The proposed techniques do not contribute a voltage balancing issues such as in multilevel neutral point clamped (NPC) inverters. The author analyzed the performance of five-phase VSI based on THD and fundamental components. Matlab/Simulink model has provided for results verification.

Pulse Width Modulation Switching Schemes for Two-Level Five-Phase Voltage Source Inverter

This paper proposes pulse width modulation schemes for a two-level five-phase voltage source inverter. According to the literature, the generation of a pure sinusoidal waveform requires an (n-1) number of vectors for 'n' number of phases, so in a five-phase system, a minimum of four-vectors is needed to generate a sinusoidal waveform. The author uses only two large vectors in this paper for a five-phase voltage source inverter. Vector diagram, switching table, and switching waveform have presented for two adjacent large space vectors. The performance for each PWM scheme is analyze based on fundamental components and total harmonic distortion. In last, results have verified in the Simulink environment.

Analysis and Performance of Five-Phase Piecewise-Random-Switching-Frequency Space Vector Pulse Width Modulation

In order to better address the problem of many high-order harmonics' concentration in the output voltage, a novel five-phase piecewise-random-switching-frequency space vector pulse width modulation (PRSF-SVPWM) strategy is proposed for a five-phase voltage source inverter. Compared to the conventional random switching frequency SVPWM (RSF-SVPWM), the entire fundamental period of this method is divided into two half-fundamental periods, so the original switching frequency in a single fundamental period is randomized in segments respectively. During this process, parameters named the offset frequency and random frequency are defined and assigned reasonably. In this way, high-frequency harmonics in one period are spread into a wider range. Subsequent simulation and experimental results verify that the proposed random modulation strategy can further reduce amplitudes of harmonics near switching frequency and its integer multiples, even though within a narrow switching frequency range, and a satisfactory effect of high-order harmonic dispersion is finally obtained, which contributes to the application and popularization of random pulse width modulation strategies.

Comparative Analysis of SVM Techniques for a Five-Phase VSI Based on SiC Devices

Multiphase systems provides benefits compared to three-phase systems, such as improved torque per ampere, high power density, better fault tolerance, lower current per phase (due to power-splitting among a higher number of phases), and lower torque ripple, among others. Depending on the application, the system must meet determined requirements, such as the presence of harmonic content, power losses, and common-mode voltage (CMV) generation. This paper presents a comparative analysis of space vector modulation (SVM) techniques applied to a five-phase voltage source inverter with SiC switches to provide an overview of their performance. The performance of five-phase 2L SVPWM (space vector pulse width modulation), 2L+2M SVPWM, 4L SVPWM techniques, and their discontinuous versions, are analyzed by focusing on harmonic content, power losses, and CMV generation using SiC semiconductor devices. Matlab/Simulink and PLECS simulations are performed to achieve the above mentioned goal. The use of different techniques allows (1) reducing the harmonic distortion when 2L+2M SVPWM and 4L SVPWM are applied, and (2) the switching sequence of the modulation techniques can influence the switching losses. Therefore, the use of SiC switches reduces the switching losses. (3) However, CMV dv/dt increases. Therefore, it is possible to minimize the effects of the CMV dv/dt and amplitude by choosing the adequate technique.

Modulated Finite-Control-Set Model Predictive Current Control for Five-Phase Voltage-Source Inverter

Due to the fixed and limited sampling period in the real-time system, three-phase inverters using finite-control-set model predictive current control (FCS-MPCC) usually suffer from large ripples of phase current. Moreover, the extension of FCS-MPCC scheme to a multiphase system always faces another challenge, which is to simultaneously regulate the fundamental and the low-order harmonic current components. For the case of the five-phase voltage source inverter that has been widely investigated recently, the existing literature has solved the harmonic currents issues with the utilization of virtual voltage vectors. But these virtual voltage vectors are still limited to the fixed angles and magnitudes in the space coordinate and lack effective current ripples suppression means. Therefore, this paper first applies virtual vectors to reduce the lower order harmonic currents and thus eliminates the weighting factor in cost function. Then, based on duty-cycle optimization, a modulated control set synthesized through virtual voltage vectors is employed to attain a smoother phase current waveform. Compared to existing methods, the vector selection and duty-cycle determination can be implemented simultaneously. Finally, a comparison of the proposed modulated FCS-MPCC scheme and the other FCS-MPCCs is presented. Simulation and experimental results verify that the proposed scheme can remain the simplified structure, fast dynamic performance, constant switching frequency, and achieve minimal current ripples.

A Modulation Method Based on a Generalised Solution of the Five-Phase Voltage-Time Law

The modulation law of the two-level five-phase voltage source inverters is modelled with two decoupled subspaces and their respective reference voltages. A new voltage-time system based on the duty cycles for this topology is presented in this article. Then, an alternative scheme to the space vector modulation is developed by deriving an analytic solution for the case of study, which is achieved with a low-computational cost algorithm. The strategy reckons the duty periods of the power switches immediately and can be implemented straightforwardly in a digital controller. The zero-sequence voltage is also considered to provide multifrequency operation either in continuous or discontinuous switching modes. The experimental validation, considering the time and frequency responses, supports the theoretical derivations in the introduction of this new method.

Third harmonic injection pulse-width modulation technique for a five-phase voltage source inverter

&lt;span&gt;Nowadays application of advanced power electronic technology enables producing an AC supply with a phase number higher than three-phase. Five-phase voltage source inverters (5ph-VSI) have been used in advanced power electronic drives to improve the reliability of the drive system and to boost the power capability of the converter as well as to their other inherent merits. This paper shows the mathematical analysis and simulation of the third harmonic injection pulse width modulation (THI-PWM) 5ph-VSI connected with inductive load in three scenarios i.e. star, Pentagon and pentacle. The presented THI-PWM technique for 5ph-VSI aims to increase the inverter fundamental voltage and hence to maximize the utilization of the DC bus without causing over-modulation. The simulation results are compared with typical sinusoidal pulse width modulation (SPWM) and the 10-step mode operation. The proposed scheme may be considered as a compromise case between the two reference cases; as low harmonic components compared with 10-step mode operation and a high utilization factor compared with SPWM.&lt;/span&gt;

Performance Comparison of Five-Phase Three-Level NPC to Five-Phase Two-Level VSI

A multiphase multilevel voltage source inverter (VSI) offers excellent advantages over the traditional three-phase counterparts. Low-order harmonic components with reduced switching losses, lower common-mode voltage (CMV), and the optimum use of dc-link voltage constitute the critical performance indicators for high-efficiency VSI evaluation. Various approaches for carrier-based pulsewidth modulation (CPWM) generation are available in the literature along with space vector pulsewidth modulation (SVPWM) techniques. Comparative analysis shows that the majority of SVPWM strategies have enormous potential than CPWM to achieve the aforementioned performance indices. The main objective of this article is to provide a common platform for the selection of available five-phase VSIs for various industrial applications. For this, a comparative study is carried out to examine in various aspects like CMV, voltage and current total harmonic distortion (THD), switching, conduction losses, and efficiency under the steady-state and dynamic loading conditions over a wide range of the modulation index. It is observed that the five-phase three-level neutral-point-clamped (NPC) VSI has better performance than the five-phase two-level VSI. Experimental results are provided to verify the performance indices of both topologies at steady-state and dynamic conditions.

Analysis of Scalar PWM Approach With Optimal Common-Mode Voltage Reduction Technique for Five-Phase Inverters

Research on common-mode-voltage (CMV) reduction in multiphase drive systems has recently met an intensified interest in the available literature. This paper first explores two existing space-vector-based CMV reduction (CMVR) schemes for five-phase voltage source inverters, represented as CMVR1 and CMVR2, which reduce the CMV by 40% and 80%, respectively. Moreover, a new space-vector-based CMVR scheme, termed as CMVR3, is proposed that not only minimizes the CMV but also reduces the overall switching losses when compared with the other schemes. The optimal duty cycles and the switching sequence of all schemes are introduced. Since the implementation of space-vector-based schemes using look-up tables is a relatively complex and time-consuming process, this paper proposes a simpler scalar PWM approach. This approach can easily be implemented using embedded PWM modules of most commercial digital signal processors. To evaluate the performance of the presented CMVR schemes, a detailed evaluation study is presented. The optimal CMVR scheme over the full modulation index range is also highlighted. The theoretical findings are verified using a prototype five-phase induction machine through simulations and experimentally.

Performance and Evaluation of Five-Phase Dual Random SVPWM Strategy With Optimized Probability Density Function

This paper presents a five-phase dual random space vector pulsewidth modulation (FPDR-SVPWM) strategy with an optimized probability density function (PDF) for a five-phase voltage-source inverter, and its performance and evaluation are also analyzed. Based on the nearest four vectors modulation method, the FPDR-SVPWM strategy, combined with random switching frequency and random zero vector, is investigated to significantly reduce the amplitude of high-order harmonics near the switching frequency and its integer multiples. For the nonsinusoidal power supply, third harmonic injection is introduced in this modulation strategy as well. Considering the effect of random numbers on the performance, an optimized Beta distribution is studied in detail. In order to analyze harmonic dispersion degree qualitatively and quantitatively, the power spectral density and the harmonic spread factor are both employed to assess the performance of the FPDR-SVPWM strategy. A series of results of simulation in MATLAB and experiments based on field programmable gate array demonstrate that the proposed modulation strategy is correct and valid, and it distributes high-order harmonics into a wide range without affecting the fundamental wave and third harmonic.

Dual-frequency discontinuous space vector pulse width modulation for five-phase voltage source inverter with harmonic injection

This paper proposes a dual-frequency discontinuous space vector pulse width modulation (DFDSVPWM) for the five-phase voltage source inverter with harmonic injection. In this modulation, for dual-frequency voltage output and reduction of switching losses, two different zero-vector-inserted modes are flexibly employed by using two types of zero vectors alternatively. Based on the comparison with continuous SVPWM, the idea and principle of the proposed DFDSVPWM are analyzed and an example of PWM signals of one bridge is also presented. For switching losses analysis, the impact factors and the calculation method are investigated and the corresponding implementation is given as well. The simulation and experimental results from a prototype verily the correctness and effectiveness of the proposed modulation and it has the advantages of outputting dual-frequency voltage and reducing switching losses.