Comparative study of switching controls in vibration and acoustic noise reductions for switched reluctance motor

A comparative study of vibration and acoustic noise reductions via electronic switching controls for switched reluctance motor (SRM) is presented. First, studies concerning the acoustic noise and vibration sources, their effects and the existing mitigation approaches are given. Then five switching control approaches, which belong to the magnetic and electronic remedies, are proposed and applied to the established SRM drive to comparatively evaluate their effectiveness and limitations. These approaches include random frequency pulse width modulation with harmonic spectrum shaping, turn-on and turn-off angles advanced shift with fixed dwell angle, randomising turn-off angle, current-tail profiling without and with advancing commutation shift. The theoretical basis, implementation and performance evaluation of each approach are presented in detail. Comparative evaluation shows that the hybrid approach combining the current-tail profiling and the commutation advancing can yield the best compromise performance in vibration reduction, acoustic noise reduction and improved energy conversion efficiency.