| 摘要 |
PURPOSE:To reduce a noise which is generated by an AC motor driven by a PWM inverter by superposing an AC signal on either one of a current command pattern signal of a current detection signal. CONSTITUTION:An inverter 3 has self-extinguishing elements SUP, SVP, SWN such as GTOs or thyristors connected in Graets manner, and feedback diodes SUP, SVY, SWN connected in antiparallel to the respective self-extinguishing elements. An induction motor 4 is connected to the AC output terminal of each phase of the inverter 3. A signal generator 12 is provided, an AC signal which is generaed by the generator 12 is superposed on a current command pattern or a current detection signal, and the inverter 3 is driven by the signal. |
