Prediction Of Tooth Root Crack Growth Life Of Wind Turbine Gearbox And Analysis Of Its Influence Factors

Wind energy is one of the effective ways to solve the current energy crisis and the environmental crisis. Wind power is the main way of wind energy using, and had a significant development recent years. The gearbox is one of the most important component of the non-direct-drive wind turbine. It's reliability requirements is very high, and design life exceed 20 years. Fatigue fracture of gear tooth resulting from fatigue crack growth is the most serious form of failure. Therefore, prediction of tooth root crack growth life of wind turbine gearbox has significance. This paper predicted crack growth life of gear of wind turbine gearbox, and analyzed influence of three factors on crack growth life.Based on an impeller aerodynamic load model, a transmission dynamic model and a tooth root crack growth model, a whole residual life calculation model of gear root crack growth on wind turbine was established. Targeting the sun gear of planetary of wind turbine gearbox, crack growth life of gear of wind turbine gearbox was predicted under random wind speed of Dabancheng wind farm. The crack growth residual life is 4249 hours.Based on the prediction model of crack growth life, the influence of single factor on crack growth life was analyzed. Different emergency braking model, internal dynamic process model of gearbox, and fracture performance degradation model of gear material were established. The influence level and influence process of three factors on crack growth life was analyzed. Emergency braking has the biggest influences on crack growth residual life, and fracture performance degradation of gear material has the least influences on crack growth residual life.Based on the analysis of the influence of single factor on crack growth life, the influence of coupling of two factors on crack growth life was analyzed. The coupling model of different emergency braking and internal dynamic process of gearbox, the coupling model of internal dynamic process of gearbox and fracture performance degradation of gear material were established. The influence level and influence process of tow coupling model on crack growth life was analyzed. When the influence of coupling of two factors was considered, crack growth residual life decreased more.