Time-varying sliding mode control for a faulted six phase induction machine

In this paper, a new variable structure position control law for a Six Phase Induction Machine (6PIM) is proposed. The algorithm based on a time-varying switching line guarantees the existence of sliding mode since the beginning of the shaft motion. Indeed, the surface is initially designed to pass through the initial representative point and subsequently moved towards a predetermined desired surface via shifting. With this algorithm, the reaching phase is removed and the motor behaviour is exactly the same in healthy or in faulted mode (loss of one or more stator phases). The capacities of this control technique have been first tested in simulation and then validated experimentally on a test bed.