Research On VSCF AC Excitation Doubly-fed Wind Energy Generation Control System

The AC doubly-fed VSCF wind power systems because of its power electronic converters capacity is small, has the good input/output characteristics and simple control system, so it becomes the focus of attention. Detailed analysis and simulate the wind turbine theory, the grid side PWM converter principle and AC doubly-fed wind power system the maximum wind power tracing theory.This paper firstly summarize of the wind power technology development at home and abroad, and point out the development trend of wind power, the abroad wind power technology and policy on China's influence and inspiration. This paper describes the existing technical bottleneck problems and the research direction about the wind power and analyzed the doubly-fed VSCF wind power technology principle and topology structure.Detailed analysis the wind power theory and wind turbines theory. Derived the wind machine output power and wind speed and the relationship between the generator speed. Finally,the simulation of wind turbine is given.Given the doubly-fed induction machine in two phase rotation of the mathematical model on mt coordinate system, deduced the doubly-fed induction machine power distribution relationship between the stator flux coordinate system, and based on the four operating condition (super synchronous speed driven/super synchronous speed generating, under synchronous speed driven/under synchronous speed generating) vector diagram, the simulation results proved the results are correct.The article thoroughly analysis the grid side PWM converter, including the main circuit topology structure, mathematical model, based on the network voltage directional double closed loop control system, and introduced the selection method of DC capacitor. Through the simulation verify the correctness of the waveform control system.Analyze the maximum wind power tracking process and theory of AC doubly-fed wind power system and stator flux oriented vector control theory. Given a maximum wind power tracking vector control scheme and system structure, the simulation results verified the correctness of the scheme. Finally, based on the TMS320LF2812DSP, designed the control circuit topology structure of PWM reversible rectifier, and the software flow chart is also showed, the wave and results of tests verified the control system is corrected.