Multi-mode Soft Switching Variable Pitch Control Of Wind Turbines Based On T-S Fuzzy Weighted

The variable pitch control method is the research difficulties of large wind turbines control technology,especially,it is very important to reduce the mechanical load and control the constant power operation of wind turbines above the rated wind speed.Taking 2MW permanent magnet direct drive wind turbine as the research object,aiming at the variable pitch control of wind turbines operating at constant power above rated wind speed,a multi-mode soft switching variable pitch control strategy is proposed based on Takagi-Sugeno(T-S)fuzzy weighted,this dissertation constructs dual-mode soft switching variable pitch control,in order to solve the problems existing in the two-mode soft switching variable pitch control,three-mode soft switching variable pitch control based on T-S fuzzy weighted is put forward,fuzzy-PID dual-mode soft switching variable pitch control and fuzzy adaptive-PID dual-mode soft switching variable pitch control are included in the former and fuzzy-fuzzy adaptive PID-PI three-mode soft switching variable pitch control and fuzzy-radial basis function(RBF)neural network PID-PI three-mode soft switching variable pitch control are in the latter.Firstly,the research background and significance of the subject are clarified,the overall structure and working environment of 2MW permanent magnet direct drive wind turbines are understood.On this basis,the mathematical models of each part of the wind turbine and three kinds of wind speed are established.The simulation models of each part of the unit and three kinds of wind speed as well as the whole simulation model of the pitch control of 2MW permanent magnet direct drive wind turbine variable pitch control are also built.The variable pitch controller is designed from two angles that reduce the mechanical fatigue load of the wind turbine and ensure the constant power operation of wind turbine.Secondly,the T-S fuzzy reasoning model is used to design the two-mode soft switching link to solve the oscillation of two-mode switch,the related control parameters of each control method are designed and optimized.At the two wind speed model,the effectiveness of the fuzzy-PID dual-mode soft switching variable pitch control and the fuzzy adaptive PID-PID dual-mode soft switching variable pitch control are verified.The step wind speed validates the anti-interference performance of two-mode control and the turbulent wind speed verifies the control performance of two-mode soft switching variable pitch control.Finally,in order to solve the problem of two-mode soft switching variable pitch control,a three-mode soft switching variable pitch control is proposed,the T-S fuzzy reasoning is used to design the three-mode soft switching link to solve the oscillation of three-mode switch,the related parameters of each control method are designed and optimized.At the two wind speed,the effectiveness of the fuzzy-fuzzy adaptive PID-PI three-mode soft switching variable pitch control and the fuzzy-RBF neural network-PID three-mode soft switching variable pitch control are verified.The step wind speed validates the anti-interference performance of three-mode control and the combined wind speed verifies the control performance of three-mode soft switching variable pitch control.