1D simulation of pump-turbine transition

Variable speed motor-generators based on full size converter offer new options for operation of reversible pump-turbines. To explore the challenges related with this new technology a specific test rig configuration is developed to perform such transition with a PT reduced scale model. Transition from pump to turbine and vice versa are performed with various guide vanes opening and transition time. In order to extrapolate the results obtained at model scale to prototype, it is important to understand the system behaviour including the waterways and its influence on the flow in the pump-turbine. For this purpose, a 1D model of the test rig is realised. After validation with measurement results, the 1D model has been used to test the influence of the waterway on the pump-turbine transition.