Active Power Response Rapidity of Variable Speed Pumped Storage Units with Full-Size Converter under Different Coordination Control Modes

The variable-speed pumped storage unit (VSPSU) with full-size converter (FSC) is characterized by its wide regulation range and fast power response. There is a significant difference in active power responses under two coordination control modes—fast power control mode and fast speed control mode. Quantitative comparison of power response rapidity under two control modes needs to be studied. In this paper, a model of a variable-speed pumped storage plant with full-size converter in turbine condition is built by applying MATLAB/Simulink. An evaluation system of power response rapidity (A_<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">vspsu</inf>) is established by application of Analytic Hierarchy Process (AHP). Power step commands and slope commands are set for numerical simulations to analyze regulation characteristics and quantify differences in active power response rapidity under two control modes. Preliminary results demonstrate that, under step commands, when power decreases by 10%, 20%, and 30%, A_<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">vspsu</inf> in fast power control mode is 2.2, 3.4, and 8.1 times A_<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">vspsu</inf> in fast speed control mode, respectively; under slope commands, when power decreases by 10%, 20%, and 30%, A_<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">vspsu</inf> in fast power control mode is 1.9, 3.4, and 15.0 times A_<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">vspsu</inf> in fast speed control mode, respectively. Under both types of power command signals, as the magnitude of power reduction increases, advantages in power response rapidity under fast power control mode become more evident. This paper could contribute to the selection of coordination control modes of a variable-speed pumped storage plant with full-size converter.