Reduction of speed ripple and vibration for switched reluctance motor drive via intelligent current profiling

This study presents the speed ripple and vibration reductions for a switch-mode rectifier (SMR) fed switched reluctance motor (SRM) drive via intelligent current profiling approach. Firstly, the SRM drive with a boost-type SMR front-end is established, which possesses well-regulated DC-link voltage and good AC line drawn power quality. Secondly, the speed ripple generating process of a SRM is explored. Accordingly, a robust and intelligent speed ripple reduction approach is proposed, wherein the leading edge of winding current command is modified by adding a compensating component, which is automatically generated from the DC-link negative stroke spikes caused by non-ideal commutation. Thirdly, a robust current error cancellation control scheme is designed to yield closer current waveform tracking response, and thus the smoother motor developed torque. In outer loop, a robust speed ripple cancellation control scheme is employed to directly reduce the speed ripple. Finally, the commutation shift is applied to further improve the torque sharing characteristics between phases during commutation period and thus reduce the speed ripple and vibration. In addition, the commutation shift also leads to the improved torque per ampere capability of a SRM. Validity of all the proposed control approaches is demonstrated experimentally.