Stop Strategy of Three-Phase PMSM Drives with Short-Switch Fault

When a short-switch fault occurs, if a redundant topology or auxiliary circuit is not used, most of the methods used are to block the remaining healthy inverters, but this method takes a long time to stop when the motor inertia is large, which may cause the fault to spread. Therefore, it’s of great significance for practical applications to stop the motor quickly after a short-switch fault occurs. To address this problem, this paper proposes a strategy that can stop the motor safely and quickly. Firstly, it analyzes the reasons for the existence of the uncontrollable stage. Secondly, during the motor controllable stage, the faulty inverter branch is not removed, but the optimal switching state is selected through model predictive control to directly act on the inverter to optimize the deceleration time. Finally, the effectiveness of the proposed strategy was verified through simulation.