摘要 |
PURPOSE:To improve reliability, by confirming increase/decrease condition and deviation from a predetermined range of bus A frequency based on the condition of a frequency control signal and operating the direction of deviation of effective power and increase/decrease condition of frequency logically when the deviation of effective power exceeds over a predetermined level thereby judging failure of generator. CONSTITUTION:In case of parallel operation, an operating section 19 operates a reference effective power per a single generator based on total effective power of generators 1, 11 and a preset rated capacity ratio between the generators 1, 11 while operates an effective power deviation based on a reference effective power and an effective power born by the generators. Increase/ decrease condition and deviation from a predetermined range of bus frequency are confirmed based on the output condition of a frequency control signal when frequency control of the generators 1, 11 is performed while based on variation of frequency from that at a predetermined time before when frequency control of the generators 1, 11 is stopped. Then direction of deviation of effective power and increase/decrease condition of frequency are operated logically in an operating section 19 thus judging failure of generator. |