Backstepping Fault Tolerant Control for Double Star Induction Machine under Broken Rotor Bars

In this paper a Passive Fault Tolerant Control (PFTC) based on non-linear backstepping control is proposed for a Double Star Induction Machine (DSIM) under Broken Rotor Bars (BRB) fault of a squirrel-cage in order to improve its reliability and availability. The proposed PFTC is able to maintain acceptable performance in the event of BRB. This control technique guarantees robustness against uncertainties and external disturbances and is also able to deal directly with faults by compensating for the effects of the BRB fault in the machine without prior knowledge on the fault, its location and its severity. The stability of the closed-loop is verified by the exploitation of the Lyapunov theory. a comparative study is made between the proposed Fault Tolerance Control (FTC) and Sliding Mode Control (SMC) for demonstrating the performance and effectiveness of the proposed controller. The results obtained show that the proposed FTC has a better robustness against the BRB fault where the DSIM operates with acceptable performance in both speed and torque.