Quantification of Noise Benefits in Torque Control Strategies of SRM Drives

Torque Sharing Function (TSF) based control is a well-established method for the reduction of torque ripple in Switched Reluctance Motor (SRM) drives. There have not been much investigations carried out in the literature on the noise benefits of TSF based control and on the impact of the commutation angles of TSF definition on the acoustic noise in SRM. In this paper, the advantages of TSF based control in noise reduction of SRM are investigated in detail. A new TSF profile, which is characterized by a slower variation of the radial force and hence reduced vibration on the stator, is introduced. Further, the effects of variation of turn-on and overlap angles of TSF definition on the vibration and torque ripple in a closed loop control are analysed in detail, using simulations and experimental methods. Based on the analysis and experimental studies, a new strategy for the selection of turn-on and overlap angles of TSF definition has been developed for achieving reduced acoustic noise, in addition to low torque ripple. Simulation and experimental results are presented to demonstrate the effectiveness of the proposed TSF definition and angle selection strategy.