| 摘要 |
PURPOSE:To precisely detect the single operation of a generator regardless of the opening and closing of a generator breaker in a hydroelectric power station, by monitoring the ripple of the output frequency of the generator. CONSTITUTION:Comparators 11 and 12 receive the output frequency of a generator, and detect the ascent and descent over planned values of this output frequency, and generate output. Timers 23 and 24 receive the output of the comparators 11 and 12, and detects the ascent or descent over planned values of the output frequency, and subsequently measures the time from the detection of it to the detection of the descent or ascent over planned values of the output frequency, and outputs signals continuously during this measurement. Comparators 27 and 28 receive the output of the timers 23 and 24, and in case that this input is shorter than planned time, they produce output. A counter 32 receives the output of the comparators 27 and 28, and counts this input. And when the count value that the counter 32 counts within a planned time exceeds the planned value, this judges it to be the single operation of a generator. |
