摘要 |
An insulation inspection device for motors includes an inverter for driving a motor, a partial discharge detecting unit for determining soundness of the motor, and a control circuit for controlling the inverter. The control circuit adjusts a switching interval of a voltage pulse of the inverter so as to be equal to a pulse round-trip propagation time between the inverter and the motor, thereby generating surge voltage higher than driving voltage for the motor, between the motor and ground, and adjusts a switching time for each phase of the inverter, thereby generating surge voltage higher than driving voltage for the motor, between phases, thus performing insulation inspection. |