| The dynamic quality of hydro turbine regulating system directly influences the safety,reliability and power supply quality of the power station and the reliability of power supply system.Therefore,the requirement of the control method of the regulating system is higher.The hydraulic unit has more remarkable time-varying characteristics,so it is difficult to control the quality of the whole time.The research content of this thesis is based on the theory of Iterative Learning Control.In this paper,the structure of the hydraulic turbine governing system is described,and the mathematical model of the hydraulic system,such as the pressure water diversion pipeline,the electric liquid servo system and the generator are established.For this kind of system,the conventional PID control is difficult to ensure that the system has the best performance under any working conditions.On the basis of this,the paper introduces the iterative learning control method,discusses the theoretical basis of the iterative learning control,introduces the principle of iterative learning control and the controller structure and design procedure.Using the iterative learning control theory,the model of the hydraulic unit controlled by PID is established,again using MATLAB simulation test to carry out hydraulic unit under the four main working conditions that is start-up,load disturbance,frequency perturbation and load shedding,and the simulation results are compared with the conventional PID control.Simulation results,based on the SIMULINK toolbox of MATLAB,show that the iterative learning PID control algorithm has the characteristics of fast convergence speed,small overshoot,good dynamic performance,simple,robust and high repetition accuracy,and can achieve effective control of the hydraulic turbine system. |
