| The wind power is a sort of clean regenerative energy ,and the reserves is abundant in China. The wind power generation has good prospects.As one kind of late-model generating electricity technology, the variable-speed constant-frequency (VSCF) generate electricity technology which makes use of doubly-fed induction generator (DFIG) as the generating equipment has obvious advantage and broad prospects. The variable speed constant frequency generateing electricity technology can realize AC excitation by exerting three-phase alternating current with low frequency on the rotor of DFIG and output electric energy with constant-voltage and constant-frequency by adjusting the amplitude, frequency, phase of the rotor excitation current.Because the wind driven generator locates at places with abominable environment, and the mathematical model of the generating system is coupled and complex, the effects of conventional control methods are limited. The characteristic of the fuzzy control is that it can transmit the control information to control objects in the form of natural language. This process have no use for accurate mathematical model, so it can adapt to the nonlinear, big inertia and change momentarily of the wind power generation, furthermore, the fuzzy control can change natural language to algorithmic language directly, accordingly it can introduce the experience of the good operation staff and expert opinion into the control system in an attempt to receive better control effect.In this paper ,the internal and overseas status in quo of the wind driven generator is retrievaled. The background of research is pointed out. The advantages of DFIG,the keystone and the application on wind driven generator of fuzzy control are introduced. The operational characteristics of DFIG on the condition of AC excitation is analysed.The experimental system of operating characteristics on the AC excitation control of DFIG is designed.The transducer is used as AC field power supply on the experiment. The characteristic curve is depicted. At the same time, the characteristic curve can supply data for the designing and debugging of fuzzy controller. The mathematical model of DFIG on coordinate system which revolves at synchronous speed and the keystone of coordinate commutation are analyzed. On this basis, the basic elements and detailed steps of the fuzzy controller design on the active power channel of DFIG is brought forth.The researching of the AC excitation control on the rotor of DFIG is discussed in this paper. The voltage-typed double-PWM convector is used as the excitation source of the generator, and the separately excited DC motor is used as power plant to simulate the wind turbine. The C language is used to compile the system control program, and the experiment system of AC excitation control on the rotor of DFIG is established, which is on the system experimental platform based on TMS320F2812. The system hardware composition and principle of the experimental system on AC excitation control of DFIG is introduced, besides, the protective problem of Intelligent Power Module (IPM) is researched. The realization of fuzzy controller by DSP is achieved. The experimental research on excitation controller of variable-speed constant-frequency DFIG is carried through. The fuzzy controller is used as the main controller on the active power channel of the experiment on excitation controller of variable-speed constant-frequency DFIG. The experimental result is remembered.The PI adjuster on the current closed loop is designed for the purpose of making up the shortage of fuzzy controller on homeostatic control. The digital achieving algorithm of the PI adjuster is imposed to make the realization by DSP.The experimental results testify that the study of this paper is correct and viable. Each controller absolutely meets the DFIG moving control demand of VSCF. The expected effect is achieved. The base of further studies on fuzzy control used to doubly-fed generating system is established by the study of this paper.
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