Harmonic frequency spectra spread of switched reluctance motor with random carrier based pulse width modulation

ZHENG Zhiyuan, WANG Jiajun, SUN Jiahao

(School of Automation, Hangzhou Dianzi University, Hangzhou 310018, China)

Abstract: In order to solve the problem of the intrinsic vibration and acoustic noise of switched reluctance motor(SRM). Random carrier based pulse width modulation(RCPWM) was proposed to realize the frequency spectra spread for SRM. Two types of RCPWMs were applied to the current loop in the speed control of SRM, which were single random carrier based PWM and multiple random carrier based PWM. The harmonics of SRM were spread continuously to a wider frequency range. The harmonic spread factor(HSF) and total harmonic distortion (THD) were used to evaluate the frequency spectra spread performance. The control simulation models for the fourphase 8/6 SRM were built up in Matlab/Simulink environment. Simulation results show that compares with conventional PWM and hysteresis control, RCPWMs can effectively improve the harmonics frequency spread ability of SRM. The vibration and acoustic noise of SRM are related with voltage harmonics directly so that they can be reduced effectively.

Key words: switched reluctance motor; random carrier based pulse width; harmonic spread factor; total harmonic distortion; harmonic frequency spectra spread