| 摘要 |
PURPOSE:To readily remove harmonic components which are contained in an output voltage of an inverter device by providing a voltage boosting chopper at the input side of an inverter, and controlling the output voltage of the inverter with the chopper. CONSTITUTION:When a breaker 2 is closed, a rectifier control circuit 8 and an inverter control circuit 12 start operating, and the DC output voltage of a control rectifier 7 gradually rises. When the DC output voltage of the rectifier 7 reaches approximately the rated voltage, an instructing circuit 11 generates an instruction signal, a voltage boosting chopper 9 thereby starts operating, and the DC input voltage of the inverter 4 rises further up to the prescribed value. In other words, the voltage of the chopper 9 rises until the output voltage of the inverter 4 becomes equal to the voltage which is applied from a voltage reference setter. Thereafter, the output voltage of the inverter 4 is automatically controlled by the chopper 9, and the output frequency of the inverter 4 is constantly controlled by an inverter control circuit 12. |
