Effect of the variable gear mesh model in dynamic simulation of a drive train in the wind turbine

Abstract

To acquire transient response of a drive train, we consider more detailed mathematical model including variable gear mesh. The gear mesh is represented by the Fourier series. In transient analysis, gear’s angular velocity is considered as constant. It makes sense when we consider steady-state. However, the gear mesh is the only part which vary according to angular displacement. It should be considered not only by the Fourier series model but also as a modified system displacement. To establish the gear mesh model, we use a curve fitting theorem. Equations of motion are derived by the Lagrange’s equation, constrained equation and gear relation. The equations are solved by numerical integration method, the Newmark method. Through these processes, we get dynamic results including angular displacement, velocity, acceleration, gear mesh contact forces. Also, the Fourier transform is used to see signals more detailed. At last, we compared the variable gear mesh and constant gear mesh, gave physical meaning, and analyzed cause of the phenomenon.