Damage Analysis of Planetary Gear Train in Wind Turbine Gearbox

Abstract

Wind turbine industry is meaningful for the energy safety, but there are still some bottlenecks with the development of the wind turbine technology. How to improve the fatigue life and reliability of wind turbines has become a major problem. In this paper, the 1.5MW wind turbine gearbox was used as an example to study the damage mechanism of the planetary gear train. First, the chemical compositions, tensile properties, Rockwell hardness, impact energy and carburized depth of the gear and bearing material were measured, and the result shows that all the above-mentioned parameters can meet the design requirements, which means they are not the reasons causing the damage of the gear. Second, based on the actual patterns of the damaged components, the main source of damage is deduced to be the inner-hole surface of the planet gear. Further, the curves of the maximum sliding distance with respect to load under different fit tolerances (P6 & R6) were compared. As a result, P6 is found not a rational fit tolerance for the planetary gear train, and it is the main reason causing the damage of the gearbox. Therefore, fit tolerance R6 should be chosen for the design.