Abstract:Wind energy is the most widely used clean energy. With the continuous development and utilization of the new energy, the installed capacity of wind power generator is increasing steadily. However, there is a problem that wind turbine generator has a high failure rate. By analyzing the research status of fault diagnosis of wind turbine, it was found the gear box failure rate is the highest, and the failure rate of wind turbine gearbox was significantly higher than the ordinary gear box. Through researched a typical wind turbine gearbox by simulation, the root reason and functional mechanism of the high failure rate of the gearbox were researched. The improvement measures on the structure are put forward accordingly, and the verification is carried out effectively, it provides an important reference for the design and operation of wind turbine gearbox.