Patent attributes
A pumped storage power plant performs a pumping operation by using a pump turbine, upper and lower regulating reservoirs. An upper space of one of the reservoirs is sealable. The pumped storage power plant detects an air pressure in the upper space, first and second water levels of the one and the other reservoirs. A controller of the pumped storage power plant obtains information of the detected air pressure, first and second water levels, and an electrical energy input from an external grid and used during the pumping operation. A calculation water level of the one reservoir is calculated by using the first water level and the air pressure. The controller adjusts the air pressure such that a difference between the second water level and the calculation water level becomes a desired difference that is determined by a characteristic of the pump turbine depending on the input electrical energy.