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In this paper, a model predictive current controller (MPCC) is proposed for short-pitched mutually coupled switched reluctance machines (MCSRMs) using a three-phase voltage source converter (VSC) to achieve fast dynamics and advanced current tracking ability. Due to strong mutually coupling between phases, to our knowledge, MPCC for MCSRMs has not been studied yet. A two-order flux-based prediction model of the MCSRMs using the VSC is presented with standard state space equations in discrete-time domain, based on which, the current regulation is achieved by solving a constrained optimization problem. With the receding optimal duty ratio input, MPCC demonstrates good current tracking ability, which is verified by simulations with a three-phase, sinusoidal excitation 12/8 MCSRM. Compared to hysteresis current control, the current response with MPCC bears lower current ripples and a fixed switching frequency. 

In this paper, a sliding mode current controller (SMC) is proposed for mutually coupled switched reluctance machines (MCSRMs) using a three-phase voltage source converter (VSC). A generalized state-space model of MCSRMs is first presented using a three-phase voltage source converter. Asymmetric bridge converters and three-phase voltage source converter are compared in terms of switching frequency. A sliding mode current controller is then designed to achieve constant switching frequency and lower sampling rate using a three-phase VSC. The stability analysis of the sliding controller is given to ensure the stability of the controller. Finally, the effectiveness of SMC is verified through simulation studies with a three-phase, sinusoidal excitation 12/8 MCSRM over a wide speed range. Compared to the hysteresis current control, SMC demonstrates a comparable performance in terms of torque ripples, torque root-mean-square tracking errors (RMSE) and current RMSE while achieving a constant switching frequency and much lower sampling rate.