Research On The Turbine Digital Electric Hydraulic Control System Modeling Simulation And Parameter Optimization Based On The Method Of Modified Particle Swarm Optimization

Turbine control is an important part of the overall power plant control. Digital Electric Hydraulic control system is widely used in modern turbine, its control effect is of great significance in the supply quality of the power and plant operation in the safe, stable,and economic circumstance.In this paper, we choose Reheat Turbine and its control system as the researched plant, build the mathematical model of various loops by mechanism modeling method, including electro-hydraulic converter, oil motive, inlet steam capacity, reheat steam capacity, rotor and generator power, join the typical non-linear loop, and specify the model parameters.On this basis, Digital Electric Hydraulic control system which was widely used in load-frequency control scheme was simulated by SIMULINK toolbox. Firstly, we analyze the object of each control loop, and discuss the parameter tuning method of the complex cascade control,especially consider the case when limit cycle exists in controller. Secondly, we apply the formula method, dynamic parameter method, immune PSO method to tuning each subsystem controller parameters, by comparing the step response curve of each subsystem, analysis the advantages and disadvantages of three tuning optimization method and select the best PI tuning parameters.Based on the best controller PI parameters of the controller, we obtain the response curves of turbine speed and power in different disturbance signals, and study the robustness of the control system, and summarize the control effect when parameters changed. Then, we interpret accurately primary frequency regulation features by simulation results, and discuss the problem which speed governing droop impacts on the control system. Each link and system simulation curves are agree with the actual situation, it shows that the mathematical model of the control system and the controller parameters are reasonable. Finally, we test the three controller parameters of power loop on a physical simulation unit. By comparing of the dynamic response curves under different disturbance,proved that immune PSO method has good performance parameter optimization.The turbine control system model, control strategy and parameters tuning optimization method in this paper have certain reference value,which is of great practical significance for better modeling simulation and parameter optimization of steam turbine system.