Comparative Analysis of Vibration Characteristics Testing for Different Pumped Storage Power Station Plants

The excitation force of the plant structural vibration of pumped storage power station mainly comes from hydraulic excitation, which is obviously related to the cascade combination formed by the number of runner blades and the number of movable guide vanes of the unit. The main frequency of the excitation force is closely related to the minimum pitch diameter number of the unit. The analysis of the vibration test data of the typical pumped storage power station plants showed that the structural vibration spectrum caused by the cascade combination unit with the minimum pitch diameter number equaled 1 or 2, generally manifests as a single main frequency and a large vibration amplitude of the plant. While, the structural vibration spectrum caused by the cascade combination unit with the minimum pitch diameter number equaled 4 is relatively dispersed, and the vibration amplitude of the plant is relatively low. The above research indicates that the vibration amplitude of the plant has a significant decrease by using the cascade combination unit with the minimum pitch diameter number equaled 4, which is very beneficial for the vibration reduction of the plant.