Braking torque analysis of PMSM motor under stator winding failures

Winding failure in PMSM motor can generate high braking torque in safety critical applications, where the motor was incorporated to provide assisting motoring torque. In this paper, a simple circuit-based model is presented to analytically analyze the braking torque under possible winding failure conditions. Finite element modeling is also presented along with the circuit based model, and is used to analyze the flux density distribution and to investigate the impact on motor parameters by the fault severity. Experimental tests were carried out to validate the model for different fault conditions.