Design and Manufacturing of The World’s Largest 475 MVA/460 MW Adjustable Speed Generator-Motor for Pumped Storage Hydro Electric Power Plant

摘要

Basic feasibility study and research and development of adjustable speed pumped storage system were started in the 1980’s. The world’s first commercial power plant of the adjustable speed pumped storage, Yagisawa pumped storage, was commissioned in Japan in 1990. For this plant, a 85 MVA adjustable speed generator-motor which has a cylindrical type rotor with three-phase field windings and a 25.8 MVA cycroconverter were installed, and have operated satisfactorily up to now since its commission. For last twenty years, several adjustable speed pumped storage plants have been constructed and commissioned in Japan and Europe. Unit capacity of around 350 MVA class adjustable speed generator-motors were applied to these plants.Currently, the world’s largest adjustable speed generator-motor is under construction, as Unit.4 of Kazunogawa pumped storage power station, which has maximum pumping head of 782 m in Yamanashi prefecture, Japan, and is planned to be commissioned in 2014. The adjustable speed generator-motor for Kazunogawa Unit.4 has the world’s largest unit capacity of 475 MVA/460 MW with rated rotating speed of 500±4 % min-1 which is ranked as high speed generator-motor. From a point of view of air-cooling capacity, the generator-motor’s unit capacity and rotating speed is close to the highest level of the past experiences. The peripheral speed of rotor is approximately 145 m/s at top speed of normal operation; and centrifugal force is approximately 1600 G at pump-turbine runaway speed condition.The world’s largest 475 MVA/460 MW adjustable speed generator-motor was installed within a very short period of 11 months in total; and its commissioning test is in progress. After the start of the commercial operation, it is expected this unit can contribute to the supply of electric power at peak demand and stability improvement of the power grid in Japan.With the increase of an intermittent renewable power, equipment and system to stabilize the power grid such as adjustable speed pumped storage system will be introduced and developed continually.