| 摘要 |
PURPOSE: An uninterruptible power supply system and a parallel operating method are provided to improve the stability of a system by controlling a phase angle and voltage. CONSTITUTION: A delta-delta and a delta-Y transformer(100) transmit a three-phase input voltage to a 12 pulse SCR converter(200). The 12 pulse SCR convertor produces standard DC voltage. A single phase PWM inverter(300) produces AC voltage. A controller(500) controls a parallel operation of uninterruptible power supply systems. [Reference numerals] (10) Single phase input voltage; (20) Three phase input voltage; (200) 12 pulse SCR converter; (300) Single phase PWM inverter; (400) SCR switch; (500) Controller; (AA,600) Gate driver; (BB) Input voltage, converter voltage and current; (CC) Inverter voltage and current |
