| 摘要 |
PURPOSE:To ensure a smooth restart of a synchronous motor upon AC power supply recovery by a method wherein an inverter circuit commutator capacitor is kept charged during a momentary power stoppage. CONSTITUTION:A momentary power supply interruption causes a commutation capacitor 22 to discharge, the reduced voltage resulting in a lower inverter commutation withstand capability. An auxiliary thrystor 25 when it is turned on causes the commutation capacitor 22 to be charged by a current flowing through a firt capacitor 7, the thrystor 25, a reactor 26, a commutation capacitor 22, a thrystor 20d, and a reactor 24b. This setup prevents an inverter commutation failure and enables the machine to restart upon recover from a power supply interruption of several seconds. |
