Research On Hydraulic Turbine Regulation System Based On Sliding Mode Control Technology

At present,the hydroelectric units in China have the characteristics of large capacity,complex diversion pipes and close coupling between hydroelectric and mechanical units.However,HTRS(Hydro Turbine System(HTRS)is time-varying,nonlinear and non-minimum phase,leading to difficulties in accurate modeling and control of HTRS.The control problem of HTRS is not only related to the safety and stability of the unit itself,but also affects the safe and stable operation of the power grid.Therefore,how to improve the control performance of HTRS and its dynamic response characteristics in transition process is the research focus of many scholars.At present,traditional PID control is widely used in hydropower stations.However,HTRS is characterized by variable operating conditions and frequent parameter changes,which leads to the decline of traditional PID control effect.Therefore,different control strategies are proposed to improve the system’s ability of stable operation under various operating conditions.This paper conducts an in-depth study on improving the regulation performance of HTRS controller.The main research contents are as follows:Firstly,the basic principle of HTRS is described,the working principle of each component module of HTRS is analyzed,and the mathematical models of electrohydraulic servo system,pressurized water diversion system,hydraulic turbine,generator and load are established.At the same time,the state space equation,linear model and nonlinear model of HTRS are established.Secondly,for the HTRS linear model,a sliding mode variable structure control method is adopted to improve the dynamic characteristics of the system and enhance the robustness of the system.The parameter selection method of the linear HTRS sliding mode controller and the design process of the dynamic surface are described in detail.Then,the stability of the established linear HTRS is analyzed by Lyapunov stability principle.Finally,simulation experiments under different working conditions are carried out to verify the effectiveness and feasibility of the proposed control strategy on the HTRS linear model.In order to solve the problem of poor adaptability of traditional PID Control in complex HTRS non-linearity,fuzzy PID Control and conventional Sliding Mode Control are introduced.SMC)and Inversion Sliding Mode Control(ISMC).Aiming at the nonlinear model of HTRS,the inverse sliding mode control strategy was proposed,the system controller was designed,and the simulation experiment was carried out.The control effects of fuzzy PID controller,SMC controller and ISMC controller are compared and analyzed.The simulation results show that the ISMC controller designed in this paper has smaller overshoot and better tracking effect.