Method to Transfer Transient Prototype Conditions to Closed Loop Model Test Rig

Abstract

This paper describes a method for determining the sequence of transient model test experiments in a closed loop test rig, using previous 1D simulations. An existent power plant with reversible pump turbine in the Austrian Alps serves as baseline. First, real measurement data of power jumps are reproduced in 1D simulations. These simulation results were transferred to the scaled model size via similarity laws. Of particular importance is the choice of model to prototype speed ratio whose influence has been studied more closely. Subsequently, the transient processes are simulated in a closed loop test rig. The simulations are controlled by a temporal power variation of the service pump. An iteration loop with optimizer has adapted the power in order to achieve similar conditions as in the prototype simulation. Due to the good reproducibility of the power jumps in the closed loop model test rig more demanding processes are investigated in the next step. A fast transition with load rejection and guide vane closing has been simulated, as it is state of the art. Furthermore, it was assumed that this power plant also has a full size frequency converter for fast transition from pump mode to turbine mode and vice versa applying linear speed variation. The findings of the pump behavior as well as the test rig behavior can then be used for the transient model test experiments.