| 摘要 |
PROBLEM TO BE SOLVED: To solve the conventional problem of a smoothing capacitor of small capacity being incapable of performing backup for an instantaneous power failure, in an apparatus for driving an induction motor with a circuit composed of a rectifying circuit, the smoothing capacitor and an inverter. SOLUTION: The induction motor 1 is driven by the rectifying circuit 5, the smoothing capacitor 6, and the variable-frequency variable-voltage inverter 7. The inverter 7 is constituted so as to be regeneratable. By reducing the output frequency and the output voltage of the inverter 7 at an instantaneous power failure, a regenerative operation is conducted, and the voltage of the smoothing capacitor 6 is controlled so as to be kept at a lower level than its normal one. |
