| With the coming mature of the wind energy technology, both the foreign and native researchers are exploring and researching in area of the power system integration of wind power, and they have drawn some conclusions. With the increasing scale of wind power generation system, the grid-connection control and the maxim wind power capture operation principle become research hotspots.With the operation and control of DFIG system as the research subject, this dissertation made complete study by simulation. The main research contents include: the operation theory of doubly-fed induction generator, grid-connection and decoupled control of DFIG active & reactive.First, this dissertation analyzes DFIG operation theory, including mathematic model of DFIG and power relationship of DFIG, which establishes the theoretical foundation for succeeding study. The second, based on the analysis of the mathematic models of no-load and isolated load grid-connection, the dissertation discusses the grid-connection control principle, builds the controls which base on stator flux oriented vector control technique, can't affect by speed. The third, based on the analysis of the mathematic model of DFIG, the dissertation discusses the control to capture the maxim wind power, field oriented vector control technique was applied to DFIG control and the calculation method of the referenced active & reactive power of DFIG was given. The last, analyzes the mathematic model and control of DFIG when voltage-dip and gives the excitation control.An integrated simulation model of DFIG system was founded including wind turbine model and DFIG models. By time-sharing method, the grid-connection simulation subsystem and generation simulation subsystem in the model finished the whole simulation progress, which includes grid-connection control and the operation control. The controls of isolated load grid-connection and the maxim wind power capture are simulated respectively to testify the validity of the theories.
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