Research On MPPT Variable Pitch Control System For Wind Power Generation

At present,the extremely prominent hot topic is wind energy among renewable resources.The effective development and utilization of wind energy will be contributed to protecting the ecology in the earth,reduce greenhouse gases and reduce dependence on fossil energy.The wind power resource is considered as an important constituent part in sustainable development of energy market and power market.However,since wind energy is featured with the lower energy density and the large randomness,it is hard to accurately judge wind changes.By aiming at these problems and improving power stability,a more effective anti-interference self-adaption control is proposed to track the maximum power point in the wind turbine system.Considering nonlinearity and hysteresis of the wind turbine system,the poor anti-jamming capacity of the traditional feather PID control mode is easy to result in power fluctuation.In this thesis,the variable speed pitch-controlled system is considered as a research object.1.5MW direct-driven permanent magnet synchronous motor is used as the power generation unit of wind power system.The draught fan is operated at the slow speed of revolution.The electric feather is selected as the variable pitch servo system,because electric feather mechanism can satisfy loads of blades.Based on the Betz Theory,aerodynamic analysis and calculation of blades are used to explore the relationship between pitch angle and power.The systemic properties are utilized to propose the fuzzy self-adaption PID control method by combining fuzzy control with traditional PID.The corresponding mathematical and simulation model is constructed to verify nonlinearity,time-dependent nature and power tracking efect of pure time delay.Simulation experiments show fuzzy adaptive PID control is applied to the pitch system,the advantages of both algorithms may be incorporated,by paddles in it dynamically adjusts the pitch angle of the wind speed,can be well adapted to non?linear,strongly coupled wind power system,The robustness of the system is enhanced,the steady-state error of the system is reduced,and finally the maximum power point tracking of the wind power system is achieved.