Diagnosis of stator winding short circuit faults in a direct torque controlled interior permanent magnet synchronous motor

Direct torque control (DTC) is a powerful control method for interior permanent magnet synchronous motor (IPMSM), it provides a systematic solution in improving the operation characteristics of not only the motor but also the voltage source inverter(VSI). Stator winding faults due to short circuited turns are one of the most electrical faults in DTC-IPMSM drive system. The main problem with fault is connected with their destructive character and a tendency to a rapid transition. In early stage of this failure, the motor may still operate. This paper presents a direct torque control for IPMSM motor under stator winding faults, in order to ensure system service continuity. As a very fast diagnosis could terminate the damage range in the stator winding, a proposed method based on the current space pattern recognition will be investigated. Comparisons between simulation and experimental results will be performed to evaluate the effectiveness of the proposed approach.