Pumped storage is a very known well form of generating and storing electric energy. With the integration of renewable energy sources and related changes in the grid, energy storage has become much more important.
Static frequency converters allow one to adapt the rotating speed of the pump-turbine and thereby optimize operation. This opens the possibility of dynamically adapting the output power of the plant and support the grid through frequency control operation. Besides that, the hydraulic efficiency of the plant can be increased, and its operation and control become much more flexible.
Hitachi Energy is a pioneer in hydro pumped storage: We have set a world record with the largest ever built converter for pumped storage application in the Swiss alps in 2012, and we have continued the journey of innovation with the Hydro SFC Light, the first direct modular multilevel converter (MMC) converter used for hydro pumped storage, commissioned in Austria in 2021.