Stability Criterion for Mass Oscillation in the Surge Tank of a Hydropower Station Considering Velocity Head and Throttle Loss

Surge tanks (STs) are important facilities for ensuring the safety of hydropower stations. Reducing ST size under premise stable mass oscillations within is main issue. First, according to basic equations oscillation a station with an ST, novel expression critical stability section deduced considering velocity head and throttle loss. Then, sensitivity each influencing factor proposed criterion analyzed. Ultimately, through simulation small transients in two case studies, water level (WLOs) based on three criteria compared. The results show that 20% smaller may result 10.4% larger 60% pumped storage power 14.3% oscillations. Compared Thoma Chinese specification criterion, this paper can safely reduce since it considers influence provide reference optimal design STs.