Stability Analysis of Pelton Hydropower Units Under Different Operating Conditions in Isolated Grid
There are a large number of hydropower stations with Pelton turbine in southwestern region,which have weak connections with the power grid and prominent stability issues in isolated grid operation.This article establishes a mathematical model of Pelton turbine,improves the analysis model for the isolated grid of Pelton turbine,and studies the stable range of control parameters for Pelton turbine in isolated grid.Firstly,a nonlinear model of the Pelton turbine is established based on the actual situation of the hydropower station.Secondly,stability analysis is conducted based on the Lyapunov first method.The state equation is established by linearizing the Pelton turbine at different operating condi-tions,calculating the relevant transfer coefficients,and substituting them into the isolated grid analysis model.The sta-bility region is determined based on the critical stability conditions.Finally,the analysis results are validated through nonlinear model simulation.The results indicate that the changes in the opening of the spray needle have a significant im-pact on the operating stability region and cannot be ignored.When adjusting the parameters of the governor,it is necessa-ry to analyze all operating conditions and optimize the parameters according to the minimum stable region conditions.
万方数据
维普
