Hybrid space‐vector pulse width modulation strategies for a four‐level open‐end winding induction motor drive with an improvised harmonic performance and balanced DC ‐link capacitors

Abstract

Summary The four‐level open‐end winding induction motor (4‐L OEWIM) drive is constituted by two 2‐level voltage source inverters (VSIs), wherein their DC‐link voltages should be maintained in the ratio of 2:1. Owing to the unsymmetrical structure of the power circuit, the 4‐L OEWIM drive is plagued with the drawback of capacitor voltage imbalance. The DC‐link capacitor of one of the inverters, which is operated with the lower voltage level, that show the propensity of getting charged up by its higher voltage counterpart, belonging to the other inverter. In this article, two variants of space‐vector pulse width modulation (SVPWM) schemes are suggested for the 4‐L OEWIM drive. The suggested sample based SVPWM techniques achieve the voltage balancing of the DC‐link capacitors, while improving the harmonic performance of the drive. Specifically, one of the two proposed PWM schemes manages to clamp one of the inverters in every sampling time interval. Hence this scheme results in lowering the total harmonic distortion (THD) in the no‐load current in most of the operating range of the drive, resulting in lower ripple in the motor phase current, lower ohmic loss and reduced torque ripple. The performances of the proposed PWM techniques are assessed with the aid of simulation studies and are validated with the experimentation.

Operation and Testing of Indirect Field Oriented Control of Asymmetrical Six-Phase Open-Ended Winding Induction Machine Using Hardware-in-Loop (HIL) Emulator

“…Operation of the motor drives was presented by using newly developed space-vector pulse width modulation (SVPWM) scheme [5], and a reduced power loss (by 4.5-11%) was reported [6]. Te authors in reference [7] have developed two schemes of SVPWM to drive open-ended winding induction motor (OEWIM), and an improved harmonic performance was reported for a wide speed range. Motor conversion efciency was maintained high over a wider load setting and operating frequencies by using the dual inverter equipped with a foating bridge capacitor [8].…”

A review on technological aspects of different PWM techniques and its comparison based on different performance parameters

“…53,54 The difference in SVPWM and SPWM lies in the fact that in SVPWM the null states (0 4 7) are divided equally in a sub-cycle duration. [55][56][57][58] The equal division of null state are made by addition of a proper common-mode signal to the SPWM. 5,59,60 At Section 4 of the paper, a complete description of space vector PWM technique has been presented.…”

“…With the advent of efficient data acquisition systems (like microprocessor, dSPACE, DSC board, and OPAL‐RT) space‐vector PWM came into play, which resulted into maximum use of DC bus voltage (DC bus utilization Factor), optimal switching reduced pulsating torque and minimized computational burden 53,54 . The difference in SVPWM and SPWM lies in the fact that in SVPWM the null states (0 4 7) are divided equally in a sub‐cycle duration 55–58 . The equal division of null state are made by addition of a proper common‐mode signal to the SPWM 5,59,60 …”

A space vectorPWMscheme for anopen‐endwinding induction motor drive with a reduced power loss

“…SVPWM strategies have also been proposed in OWIM drives with higher number of voltage levels. In the research work presented in References 18,19 a decoupled‐SVPWM based strategies for the OWIM configuration is proposed, in which both inverters are switched simultaneously, resulting in the shifting of the harmonic spectrum to double the switching frequency. Furthermore, these SVPWM strategies are extended to the 5‐phase OWIM and the OWPMSM drive configurations as well 20,21 to achieve the objectives of avoiding the common‐mode currents and reducing the ripple in the phase current.…”