The Research Of Large-scale Wind Turbine Independent Pitch Control System

Nowadays, the resource of traditional energy is shrinking. Developing green energy sourcevigorously has become an important topic of human science research. As one of the clean energyresources, wind power takes great part in energy supplying. As one of the key technologies inwind power technology，independent variable pitch control technology plays an important role inthe control of the wind turbine generator and has become the focus of the study of a number ofresearch institutes.Firstly, this paper introduces the composition, classification and working principle of thewind turbine, which become the theoretical foundation for wind turbine selecting for modelingresearch. Secondly, the paper introduces the working principle of pitch system and decides towhich type of electric drive mode should be taken use as variable pitch implementing agency.Establishing the mathematical model of wind turbine is often a complicate process. Accordingthis issue, this paper takes method of analyzing each subsystem of the wind turbine firstly. Andthen compositing every subsystem in order to establish the model of the wind turbine. Accordingto the power output can not meet the requirement in the process of simulation of the windturbine，the PID controller is designed. The PID controller is proved to be feasible in the powercontrolling by means of simulation of the CPC（Collective Pitch Control）wind turbine. But findout that the paddle axial aerodynamic change, which are caused by wind unevenness and shouldbe reduced, can make uneven distribution of blades and cause some oscillations. In this paper, amethod based the blade azimuth weight coefficient assigned in individual pitch control system isdesigned to solve this problem. As for power control in the independent variable pitch windturbine a fuzzy-PID control strategy is designed. Making use of simulink to prove the strategy isfeasible and could reduce blade load to a certain extent.