An on-line stator turn fault detection method for interior PM synchronous motor drives

An on-line stator turn fault detection scheme, which is suitable for detecting turn faults in interior PM synchronous motor (IPMSM) drives, is proposed in this paper. It is investigatted that the asymmetries in the machine parameters caused by turn faults in current-controlled voltage source inverter (CCVSI)-driven applications result in a reduced positive sequence component of the machine terminal voltages; furthermore, the reduction should be reflected in the voltage references because of the control action on the currents. It is also figured out that the variations in the voltage references can be easily observed in the synchronous rotating reference frame. Based on these facts, a stator turn fault detection method that does not require calculation of sequence components and importantly does not require measurements of the machine terminal voltages is proposed and verified through experiments.