A wind turbine suitable for project wind condition is provided, and a method to find the best performance of wind turbine is found out. Using this method, the utilization efficiency of wind energy can be increased, and the investment profit of wind power plant can be maximized. By studying the relationship between the wind turbine generator speed, wind speed, optimal tip speed and generator power, this paper uses the actual data to calculate optimal tip speed ratio of running fan, and find the generator speed-power control curve which makes the wind turbine run on the optimal tip speed ratio. This curve is used to optimize the speed controller of the wind turbine generator, so that the maximum wind energy can be obtained in a wider generator speed range at the optimal tip speed ratio. By using this method, combined with the real wind power plant case, and by optimizing the generator speed control strategy by analyzing the running data of the operation unit, it finally achieves the purpose of improving the power generation capacity of the wind turbine, and verifies the feasibility of the method. This method can also be used as a reference for the assessment of type selection of wind turbines.