Abstract: A pumped-storage unit usually works in many different conditions at high water heads with complicated flows in its draft tube, and therefore the speed control requirement for its guide vane opening and closing is quite different from general hydropower units. To meet the requirement, this paper describes a method for guide vane opening and closing rate control under different working conditions that is derived through numerical simulations of regulating guarantee in a case study of the governing system in Jilin Dunhua pump-storage units. Then, we demonstrate the design of a new flow control device that meets the requirement and is based on the principle of cartridge valves, and analyze its working principle, structure, and design characteristics, focusing on the flow control method for accident shutdown in pump and turbine modes. Finally, the device is tested and verified through laboratory experiments showing its effective performance and applicability that improves the design of guide vane speed control, accident shutdown, and over speed protection functions.

Key words: cartridge valve, flow control, turbine governor, regulating guarantee calculation, performance test, Dunhua pump-storage power station