| 摘要 |
PURPOSE:To compensate the phase difference displacement of a synchronous motor in an input zero time to a synchronous motor immediately before converting to a power supply path by providing a phase regulator for arbitrarily setting input/output phases in a synchronization detector. CONSTITUTION:A variable frequency power source 5 is first controlled to be accelerated to a synchronous motor 3 to a rated speed. Then, the fact that the voltage, frequency and phase difference between an AC power bus 1 and a starting bus 7 fall within the prescribed range is detected by a synchronization detector 10 to close a system switch 2. Here, the phase regulated value of a phase regulator 11 is set to the value of the internal phase difference displace ment of the motor 3 obtained in advance by a flywheel effect coefficient of the load of the motor 3 and the input zero time of the motor 3. Thus, when the switch 2 is closed, a rush current is not flowed to the motor 3. |
