Study on pump mode cavitation characteristic of variable speed pump turbine

The continuous variable speed technology is a key in the development of pumped storage units. When operating range rotation widened, unit's stable and safe operation will be constrained by conditions, such as cavitation, hump, power limit. This paper uses traditional fixed-speed station research object. Based on complete characteristic curves unit, modification hypothesis after application carried out, preferred curve pump working condition obtained. improvement cavitation characteristics fixed unit studied this paper, problems prediction prototypes based model tests are also analyzed. In prototype turbine analyzed using computational fluid dynamics simulation, with initial coefficient basis for judging cavitation. points out that there deviation direct through test provides more accurate method to predict limit units, which reference practical engineering.