Hydraulic design and optimization of rotary wheel for pumped storage power station

Abstract

As the core equipment for flexible peak regulation in power systems, the performance of pumped storage power stations directly affects the stability of the power grid and the efficiency of energy utilization. The impeller, as the key component of the pump-turbine, plays a critical role in bidirectional energy conversion. In pump mode, the impeller converts electrical energy into the potential energy of water; in turbine mode, it transforms the potential energy of water back into electrical energy. This bidirectional operating characteristic imposes stringent requirements on impeller design: it must simultaneously ensure high head and high efficiency under pump conditions, as well as stable operation across a wide flow range under turbine conditions. The hydraulic performance of the impeller directly determines the unit's energy conversion efficiency(accounting for 70~80% of the total efficiency) and operational stability(including issues such as pressure pulsation and vibration). The structural characteristics of the impeller were analysed and an in-depth discussion on the principles of hydraulic design, optimization method, key parameter analysis, and practical performance evaluation was carried out. The objective is to provide detailed and scientific references for the design and operation of pumped storage power stations.

Keywords

pumped storage power station / pump-turbine / impeller / hydraulic design / optimization methods / energy conversion efficiency