Dynamic Characteristics Of Gear Transmission System For Wind Turbine Speed Increasing Box

With the energy and environment problem worsening, as a clean and renewable energy, wind energy is applied broadly through out the world. The gearbox is one of the important components in wind turbine, thus, its performance has a great effect on the wind driven generator. This paper paid close attention to the gearbox for particular1.5MW wind turbine, and studied dynamic characteristics of gear transmission system under the interaction of external wind load and inner excitation.First, using lumped parameter method, a physical model of gear transmission system was established. The three translational and three torsional degrees of freedom were chosen. The text also considered the couple relation between system responses corresponding to each generalized coordinates, and analyzed the elastic deformation of gear pairs along the line of action. Based on the theorem of angular momentum about the mass center of particle system, mathematical model was found. In addition, natural frequencies of gear transmission system in wind turbine speed increasing box were obtained by calculating and simplifying bearing support stiffness.Then, nonlinear time-varying meshing stiffness and meshing error excitation of internal and external gear mesh in transmission system were computed, systemic external excitation caused by wind load was analyzed. From the foregoing, it could demonstrate the diagrams of response phase, Poincare section, time domain waveform and axis orbit. This part investigated dynamic characteristics of wind turbine gear transmission system relatively comprehensively.At last, using ANSYS and taking gear meshing stiffness into account, the finite element model of the coupling vibration combing bending, torsion, axial direction and swinging was founded in helical gear transmission. Here, beam element with3-D and6-DOF was applied in shaft segment, lumped parameter element was drawn in gear, and support stiffness of bearing was simulated by spring element. Then the nature frequency and mode shape of gear transmission were obtained, and the results were accord with the ones calculated by dynamics model of gear train system.