Abstract: The volatility and intermittency of wind speed lead to voltage stability changing of wind farm connecting power system. This paper studies the influence of local wind farm power fluctuation and the improvement strategies on grid voltage stability. In simulation model, the influences on grid voltage stability improving are researched of different reactive power compensator. Finally, with different operation sections of wind power, the grid voltage fluctuations are analyzed to evaluate the improvement effects of grid voltage stability with different reactive power compensation devices.