Fractional Modeling Of Turbine Governing System Based On TRR-PSO Algorithm

With the national development of new energy,we have to consider the inherent characteristics of new energy,which makes the hydropower units with good energy storage capacity and flexible regulation ability become more and more important for the reliable and safe operation of power grid.Therefore,the key to the stability analysis of power system is to establish a mathematical model that can accurately reflect the dynamic characteristics of hydraulic turbine governing system.In recent years,with the rapid development of fractional calculus,it has been applied in many fields,and its modeling and control ability has been proved in various engineering applications.Therefore,the fractional order calculus theory is applied to the hydraulic turbine governing system,and the fractional order model of the turbine diversion pipeline is established.Finally,based on the established fractional order model,the fractional order control is proposed and the Fractional Order PID controller is designed.In this paper,the off-line data and trr-pso optimization algorithm are used to obtain the-fractional order turbine water diversion pipeline mathematical model through identification method.First of all,data are needed for model identification,so a high-precision nonlinear turbine diversion pipe model based on full characteristic curve is established as identification data.The turbine diversion pipeline model in the form of general fractional order transfer function is established.The coefficient and order of the fractional order model are identified by trr-pso algorithm.The model identification is carried out under three operating conditions of a power station in China(operating conditions 1,2 and 3 are 0.45,0.6 and 0.75 respectively).The simulation results show that the fractional order model can better fit the wave curve of the real system and reflect the nonlinear characteristics of the turbine governing system more accurately than the integer order model.Finally,in order to prove that the Fractional Order PID controller is more suitable for the fractional order model,PSO algorithm is used to optimize the parameters of PID and Fractional Order PID respectively on the basis of the fractional order turbine governing system model.The simulation experiments under frequency disturbance and load disturbance show that the Fractional Order PID controller has better regulation performance than the integer order PID controller.