Research On Robust Control Of Maximum Power Tracking With Preset Performance For Wind Turbine Generator

Wind power,as a green and renewable energy,will develop rapidly and inevitably become a key component of China’s energy system in the context of "dual carbon".China is rich in wind resources and has great development potential.In the field of wind power,how to maximize the capture of wind energy is a major research direction.In general,the maximum wind power can be obtained through an effective power control system without changing the structure of the wind turbine.However,compared to foreign countries,China’s wind power control technology still needs to be further studied,and with the large-scale and far-reaching development of wind turbines,it has brought higher challenges to the safety and stability of wind turbines,as well as higher requirements for wind turbine control systems.In view of this,in-depth research on fan power control is of great significance.Starting with the power controller of wind power generation systems,this paper designs a maximum power controller to maximize wind energy conversion.The main research contents of this paper are as follows:(1)The aerodynamic model of a fan is introduced from three aspects: leaf element momentum theory,Bates theory,and turbulent wind model;The structure and power characteristic curve of wind turbine are analyzed and studied,and the basic principle of maximum power control is introduced;The dynamic model and transmission system model of the wind turbine under low rated wind speed are established,providing a model basis for subsequent maximum power controller design.(2)Research on the maximum power control system of wind turbines.Maximum power tracking control is an important part of the control task for variable speed wind turbines.Under rated wind speed,traditional maximum power tracking control is to track the optimal tip speed ratio to obtain maximum wind power.However,due to the strong nonlinearity and strong external disturbances of wind turbines,it is difficult to quickly respond to wind speed changes,and the tracking speed is slow,resulting in a decline in annual output.In view of this,this paper designs a new preset performance controller to achieve maximum power tracking control for wind power generation systems.Specifically,based on the idea of time-varying feedback,a time-varying function embedded with convergence time and tracking accuracy is defined,called a preset performance function,so that the convergence speed and accuracy can be specified in advance;Then,using the time-varying function,the actual specified time problem of the original system is transformed into a bounded time problem of the new system;Finally,based on the design idea of the backstepping method,this paper proposes a direct robust controller design scheme with preset performance.(3)A simulation model is established with Matlab/Simulink and other software.The simulation results show that compared to conventional sliding mode control,the preset performance maximum power robust control strategy can achieve rapid tracking of the fan speed to the most desired trajectory,with a shorter stabilization time,and the tracking error can converge to a given accuracy range within a given time.Its dynamic response speed is significantly faster than conventional sliding mode control methods.The method proposed in this paper provides a reference for maximum power tracking of wind turbines.