Application of H-infinity control to improve the current and speed loops of switched reluctance motor drives

In this paper the H-infinity robust control technique is applied to design a switched reluctance motor drive where the rotor position sensor provides just six pulses per revolution. A control system analyzer is used to obtain the frequency responses at each design step. To reduce the effect of the i nherent phase inductance variations, an H-infinity two-degree-of-freedom co ntrol scheme is designed in the current-loop of the drive to achieve the de manding time-response specifications. In order to have a good load torque d isturbance rejection ability, the H-infinity loop shaping procedure is empl oyed to construct a lead-lag type controller in the speed-loop of the drive . The designed H-infinity controllers are evaluated in real-time experiment s with a digital signal processor (DSP). The results demonstrate the effect iveness of the proposed strategy in comparison with that of a conventional design.