The Impact Of Large-scale Wind Farm Grid Power System Voltage Stability

Grid-connected wind power generation has been well developed for its special energy source, beneficial environments and dimensional benefit since1980s, which absorbs much attention about the questions accompanied with the wind power generation. The characters of wind energy will bring much negative influences with larger scale wind farm being connected to the power grid, these negative influences will restrict the wind energy development, so it is essential to investigate the influences between wind energy and power grid.Nowadays the technologies about wind power generation has got much progress, the new type generators will decrease the bad influences that brought by grid-connected wind power generation, but most of the wind farm adopt commonly asynchronous generator, some characters of asynchronous generator have a strong relationship with voltage stability. So the voltage stability is the emphasis this paper concerns.In the first two chapter of this paper, the history and development of wind energy are introduced, and then explains some correlative concepts about voltage stability, to the next the factors that influence the voltage stability after wind farm being connected to power grid are analyzed in principle. In chapter 3, the math's descriptions about every part of wind power generation system are expatiated. According to the math's description, the dynamic simulation models based on Matlab/Simulink are established. Chapter 4 discusses some of the factors that influence the voltage stability when system is under three-phase short circuit fault, such as reactive power compensator, grid coupling impedance and the rigidity coefficient between wind turbine and generator.The question about voltage stability is very complicated, this paper investigated just only a small part of it, and the more work will be done to further wind power development.