Effect of Torque and Radial Force Ripple Suppression Control Gains for Vector-controlled SRMs on Evaluation Function Value

Switched reluctance motors (SRMs) attract attention as inexpensive and robust motors that do not use rare earth materials. However, the vibration and acoustic noise of SRMs are greater than those of other motors. In addition, control is difficult due to the nonlinearity of the inductance depending on the motor shape and rotor angle. The authors proposed a control method to suppress torque ripple and radial force ripple in SRMs driven with vector control. Maps of the torque and radial force ripple ratio were created and evaluated by varying the gains K
T
and K
Fr
for suppressing the torque and radial force ripples, respectively. In this paper, the characteristics are evaluated by using three evaluation functions, torque ripple ratio, radial force ripple ratio, and the sum of those when the torque command $T^{\ast}$ is varied from 1 to 2 N and the rotation speed N is varied from 300 to $2000\min ^{-1}$. From the experimental results, changes in each ripple ratio map were observed due to changes in the rotation speed. This is because the followability to the command value of the current deteriorates at the time of high speed. These maps show that the torque and radial force ripples can be flexibly adjusted by appropriately selecting the two gains K
T
and K
Fr
.