DEVICE AND METHOD FOR DETECTING FAULT OF STATOR WINDINGS OF INVERTER-FED AC MOTOR

摘要

A method and a device for detecting a fault of a stator winding of an inverter-fed AC motor are provided to minimize damage due to an insulation breakdown by quickly detecting a disconnection in the stator winding. An AC motor includes a first phase winding, a second phase winding, and a third phase winding. Capacitors(C1,C2) are included in an inverter for driving the AC motor. A DC voltage is applied across the capacitors. Two resistors(R1,R2) are series-connected to each other. The resistors are parallel-connected to both ends of the capacitors. A zero phase voltage is obtained by measuring a potential difference between a node n between the resistors and a neutral point S of the windings of the AC motor. When the zero voltage is not zero, a defect of the stator winding is determined.