Due to the complex dynamic characteristics of hydropower units,it is easy to produce ultra-low frequency oscillation when a high proportion of hydropower participates in the frequency modulation process of the power grid,which is not conducive to the safe and stable operation of the power grid.Therefore,this paper proposed a frequency modulation method based on small signal modeling.First of all,in order to reflect the dynamic characteristics closer to the actual working state,the model of the hydropower unit participating in the power grid frequency modulation was con-structed based on small signal analysis.To consider the small signal model that will reflect the characteristics of the sys-tem such as ultra-low frequency oscillation harm,the nonlinear system was highlighted,and Fractional Order PID(FOPID)speed regulating system controller was designed;On this basis,the genetic algorithm was used to optimize the controller parameters with the minimum frequency deviation as the objective,so as to further improve the control effect.Through the simulation analysis,the small signal model established can accurately reflect the dynamic characteristics of the water turbine,and the superior performance of the FOPID controller can effectively suppress the ultra-low frequency oscillation.
关键词
水电机组/一次调频/超低频振荡/小信号模型/分数阶PID
Key words
hydropower units/primary frequency control/ultra-low frequency oscillation/small signal model/frac-tional order PID
维普
万方数据