Reactive Power-Residual-Based Stator Interturn Fault Detection in PMSM Drive

Stator interturn fault is one of the most common failures in electrical machines, which leads to catastrophic results if no prompt detection is implemented. This paper proposes a novel method to detect interturn fault for permanent magnet machine drive system, based on instantaneous reactive power residual, under interturn fault conditions. Compared to current residuals, the reactive power residual is observed to have enhanced fault signature. The reactive power residual is generated from the currents and voltages obtained from the analytical models of faulty and healthy observers. Here the proposed fault indicator is defined based on the magnitude of dc components which are extracted from negative-sequence instantaneous reactive power residuals. The robustness of the proposed fault detection under different operation region is estimated on a permanent magnet synchronous machine drive.