Chapter 12 - The effects of bending moments on the dynamics of a wind turbine planetary gearbox

Abstract

This chapter investigates the effects of bending moments on the dynamic response of a planetary three-stage gearbox used in an indirect-drive wind turbine under different load conditions. A 6-degree-of-freedom (DOF) dynamic model is developed for each of three main gearbox components by considering the main variable factors, including the time-varying mesh stiffness, static transmission error, gear backlash, and bearing clearance. A total of 18-DOF dynamic model is obtained for studying the dynamic response of planetary gearbox components. Loading conditions considered include the external excitations from wind and the internal excitations originating from the static transmission error. The nonlinear dynamic response of the wind turbine planetary gearbox components is numerically investigated with the help of time history, frequency spectrum, phase portrait, Poincare map, and load share ratio. It is found that the bending moments can affect the gear meshes, and the driving torque influences the effect of bending moments. It is also found that the planet-bearing clearance has negligible effect on the dynamic response at planetary gear stage.