A Novel Fault Diagnosis Technique for IPMSM Using Voltage Angle

Different kinds of faults in the motor can occur, which causes various and independent variations in the magnetic flux distribution of machine and consequently causes different changes in the behavior of the motor and its performance. These changes reflect in the machine flux linkage, which can be determined by the machine voltage. A novel fault detection and identification technique for inter-turn-short fault and irreversible demagnetization fault in interior permanent magnet synchronous motor are presented in this paper. The deviation caused by the inter-turn short fault and irreversible demagnetization fault in the angle between $d$-axis voltage and $q$-axis voltage, which is termed as voltage or load angle is analyzed. It is observed that in case of demagnetization fault the voltage angle increases, whereas in case of inter-turns short fault it decreases. In this study, we used this unique phenomenon for the detection and identification of these faults. The proposed method is verified by simulation and experiments.