Research On Control Stratrgies Of The Mega-watt DFIG Wind Power System

Wind energy is a clean, renewable energy and extremely rich. It is estimated that the total wind energy resources around the world is two trillion kilowatts per year.only 1% of the surface wind using will be able to meet the worldwide demand for energy. From the mid 70s of last century, wind power has been attention by the countries of the world. Today, wind power has become the most mature renewable energy technologies, and has great prospects for development in commercial value.Thus wind power has a good commercial prospects. Comprehensive resources, technical, economic, environmental and other factors, the development of wind power industry will be the most realistic means to address the shortage of energy and power in China.This paper focuses on variable speed constant frequency control strategy in depth. Articles start with the basic principle of DFIG, and obtained its three-phase static coordinate system in the mathematical model. Then by coordinate transformation, a mathematical model in the two-phase rotating (dq0) coordinates is established of the doubly fed synchronous motor of the mathematical model which has laid a theoretical foundation in studies of the wind power generation system. In this paper, by introduction of maximum wind energy Tracking mechanism it was established based on stator flux oriented control strategy of DFIG power decoupling. Using stator flux oriented vector control technique the paper analyzes the AC excited variable speed constant frequency wind power of the control strategy in grid,and analyzes the relationship between the equivalent circuit and the power balance. Finally, by introducing the dual PWM converter, it establishes that voltage vector oriented control strategy based on the grid.And the establishment of a neural PID controller and conventional PI controllers are compared.In this paper,Matlab/Simulink has been used in the doubly-fed wind turbine module and the dynamic simulation. Through the simulation results analysis, the use of vector control of doubly fed variable speed constant frequency wind power generation system has good dynamic and static performance. Meanwhile, the simulation results also prove the correctness of the control strategy.