Multi-objective Optimazation Control Of Large Scale Double-fed Wind Turbine

Along with the progress and development of human society， energy supply isbecoming more and more nervous，as a clean reenewable energy，wind power has beenwelcomed all over the word. At present， almost all large scale wind turbine adoptedvariable speed variable pitch control technology， the control technology not only canachieve maximum wind energy capture and improve power quality，but also can reducethe load of the gearbox and other components. Therefor，this artical based on the3MWvariable speed variable pitch wind turbine as the research object.Firstly，to analyze the working principle of wind turbine and establish matchematicalmodel of wind turbine. According to the size of wind speed to divide the work region ofwind turbine， study the power control method of different operational phase of windturbine. Reasearch the power control method of different work region.Secondly，traditional PID control strategy is applied to the wind turbine controller，through the simulation we found that the control effect of the control strategy is not ideal，there are some problem，like larger power fluctiong，larger gearbox and other componentsload， frequent pitch. In order to optimize the control effects of the conventional PIDcontroller，below the rated wind speed torque PID controller with drive chain damper hasbeen designed，above the rated wind speed dual PID variable gain pitch controller with atower damper has been designed. The simulation results indicate that，the optimized PIDcontroller reduced the output power fluctuations and pitch movements，decreased gearboxand other components load.Finally， aim at larger power fluctions and load and frequent pitch movement oftraditional control strategy， multi-objective control strategy of wind turbine has beendesigned based on LQG optimal control，the control strategy controls multiple targets atthe same times，so that wind turbine could achieve the purpose of the overall optimal. Withthis optimization strategy, system noise and measurement noise are estimated throughKalman filter，adjusting dynamic optimal gain according to the system of estimation，inorder to achieve optimal control of different working point. The results indicate that， compared with the conventional pitch control strategy， the LQG optimal controller notonly reduced the fluctuation of power and frequent pitch movement but also reduced thefatigue load of gearbox and other key components.This paper aims at the optimization of wind generator controller， developing theexternal controller programm of Bladed through VC++software and then simulated inBladed to verify the performance of the controller.