| 摘要 |
PROBLEM TO BE SOLVED: To reduce the facility cost and suppress the maximum required power of a main inverter device and an auxiliary machine device by providing a rectifier, a boosting transformer, and an inverter device for auxiliary machine which can be connected to the main smoothing capacitor for the main inverter device and incorporating a main current controller in the inverter device for auxiliary machine which precharges the main smoothing capacitor. SOLUTION: When a main motor 25 is started, the turned-off states of a main switch 9, an auxiliary machine switch 10, and a switch 6 for cooling fan are first confirmed. Then an auxiliary machine switch controller 36 turns on the switch 10 and a constant-current controller 32 calculates the control (switching) signal of an inverter device 1 for auxiliary machine so as to charge a smoothing capacitor 22 with a constant current and transmits the control signal to the inverter device 1. The inverter device 1 precharges the capacitor 22 by supplying necessary power to the capacitor 22 based on the control signal. |
