Hydraulic Characteristics of Pumps and Turbines

Almost all hydraulic systems in hydropower stations are constructed for turbine and pump operations. Except for Pelton turbines, at which only the injector nozzles are included in the hydraulic system, all other types of turbines and pumps are found within the hydraulic network and the pipeline system. This fact determines that to compute each hydraulic transient the hydraulic characteristics of the respective turbines and pumps must be taken into account. In case of emergency shutdowns of turbines or pumps, for instance, the extended characteristics of these machines with changeable rotational speed must be known. Furthermore, the moment of inertia of the entire rotor system plays an essential role in affecting the changing rate of rotor rotations.