| 摘要 |
PURPOSE:To permit the safe transition to power generation operation by releasing a generation motor from a system at the stage where the opening degree of a guide vane reaches a prescribed value and perfectly closing the guide vane and then opening said vane again after the water-pressure in a runner back- pressure chamber lowers to a prescribed value. CONSTITUTION:A guide-vane opening-degree detector (not shwon in the figure) detects that the guide vane 3 of a pump water-wheel in water pumping-up operation beings to close at a time t0 and a prescribed opening degree a1 is reached at a time t1, and then a power generation motor is released from a system by the detection signal. Then, the guide vane 3 is closing-operated, and perfectly closed at a time t2. Then, a water-pressure detector 11 detects that the water pressure P in a runner back-pressure chamber 10 reaches a prescribed water pressure P1 where excessive vibration or water-pressure pulsation is not generated even if the guide vane 3 is closed, and then the guide vane 3 is opened at a time t3 on the basis of the detection signal. Thus, the speedy transition to the power generation operation of the generation motor is permitted safely and certainly. |
