| 摘要 |
PURPOSE:To obtain sufficient control power supply up to a natural commutation region by providing a switch between the AC side of a power rectifier and the AC side of a power inverter, and by closing said switch at the specified time before the start of synchronous motor. CONSTITUTION:A switch 10 for giving AC power from the AC input side of a power rectifier 5 to a power inverter 7 is provided. An input circuit breaker 3 of a static starter is closed before the start, the switch 10 is closed, and an output circuit breaker 8 of the power inverter is opened. Under this condition, the main circuits of the power rectifier 5 and the power inverter 7 are charged. After the time sufficient to charge the control power supply initially required at the starting is elapsed, the switch 10 is opened. Thereafter, a synchronous motor 9 is started by the specified pattern. Therefore, even though the thyristors are controlled in a triggering circuit by the light triggering method, the starting is made stably and economically without using a complicated sequence. |
