Gearbox was a key component of wind turbine but with the highest failure rate, so it was necessary to analyze its safety and reliability. In this paper, gears in MW wind turbine gearbox were analyzed by nonlinear finite element contact analysis method. The changing regularity of the stress was found as tooth mesh, and it was proved to be reliable by comparing with the result of theoretical calculations. The maximum contact stress existed on the second engaged tooth as well as the vicinity of the pitch circle of gears. The stress concentration phenomena occurred at the tooth root fillet which caused the main failure form of gears.

As the main load-bearing component, the tower supports the weight as well as the wind force and the dynamic load in operation of the wind turbine. It also endures the blow of itself. The level of the tower design directly affects the performance of wind turbines. This paper discusses static characteristic and dynamic model anasysis of the tower of an 1.5MW horizontal axis wind turbine. It is also about choice and calculation method of finite element.

To find the changing regularity of stress and displacement, a 3MW wind-turbine main shaft was modeled and analyzed at startup time of operation. The results were verified by theoretical calculation. Parametric design of the shaft was used through orthogonal experiment method in which parameters were consisted of structural and load ones. The optimal regression equation, which indicated the relationship between the shaft stress or displacement and the parameters, was given by using polynomial regression with the test results.