Comparative Investigation of Torque-ripple Suppression Control Strategies Based on Torque-sharing Function for Switched Reluctance Motor

Torque ripple is an inherent property of switched reluctance motor (SRM), which seriously affects the control performance and application of the motor. This paper proposes two torque ripple suppression control strategies based on torque-sharing function (TSF). According to the symmetry characteristics of the flux linkage and rotor position curve family, a fourth-order Fourier series is used to fit the SRM flux linkage analytical model. The coefficient of each harmonic term of the flux linkage model is a function related to current, expressed by a sixth-order polynomial. The torque analytical formula can be derived from the flux linkage model. The torque error is calculated via the identified torque model and is compensated through TSF controller in order to reduce torque ripple. The torque model can also be used to establish the torque loop to achieve accurate tracking of the TSF reference torque to reduce torque ripple. Digital simulation was conducted, followed by the implementation on a SRM test bench using a 28335DSP as the master control chip. The experimental results are consistent with the simulation results, and indicate the effectiveness of the proposed schemes.