Robust control of switched reluctance motors for direct-drive robotic applications

This paper discusses the robust control of switched reluctance motors (SRM's) for driving manipulators directly. A mathematical model of the SRM with unmodeled dynamics is proposed which describes the relationship among electromagnetic torque, rotor angular position, and phase currents. The parameters and boundaries of the unmodeled dynamics in this model are estimated by the least square approximation method. Based on this model, a robust controller is designed. Compared with the ordinary controller, the robust controller can produce an auxiliary control input to overcome the influence of model uncertainties on system performance. Overall stability of the system is proven using Lyapunov techniques. Following a theoretical analysis, some related experiments are introduced. The experimental results show that the controller provides a steady-state performance although the system contains unmodeled certainties.