Design of Low-Torque-Ripple Switched Reluctance Motor for Shift-by-Wire Actuator

A shift-by-wire (SBW) requires a reliable, low-cost, and small-sized actuator to ensure safety and price competitiveness of the vehicle. Switched reluctance motor (SRM) is a viable option thanks to its simple construction and operation. However, SRM has relatively high torque ripple that hinders the smooth operation of the motor. In this paper, a method to reduce torque ripple by changing the rotor structure is presented. Non-uniform air-gap and two holes near the rotor surface are applied to a 12/8 SRM. Finite element analysis (FEA) is performed to observe the characteristics of the proposed design. Finally, the motor was manufactured and experiments were done to verify the effectiveness of the proposed motor.