Transmission Dynamics Analysis Of Large Wind Turbines Under A Flexible Support

Large-scale wind turbine is important wind energy machinery, but also is anaerial work facility. High reliability, low maintenance cost, and high lifeexpectancy are required for large wind turbines. With increase of unit capacity,structural dimensions of the components, tower height and flexibility graduallybecome large, while tower rigidity decreases. Large-scale wind turbine isactually a flexible multi-body system. Currently, there are much failure,poorreliability and high maintenance cost in large-scale wind turbinetransmission.dynamics behavior of large-scale wind turbine transmission systemwith high base flexibility, big change of transient load and lubricationperformance degradation is studied,and exploring its evolution and failuremechanism is a critical step to make a breakthrough on wind turbinetransmission technology at home.A combination of wind speed mathematical models withMATLAB/Simulink is used to simulate random wind for600s, according to thecharacteristics of natural wind. Then, input torque、 input power and axial thrustof variation-pitch VSCF wind turbine generator are calculated based onknowledge of aerodynamics. The wind turbine impeller/cabin/tower couplingdynamics equations are established by Lagrange equation, which is solvedthrough Matlab to analyze the dynamic response of the blade and the tower.Dynamics model of wind turbine transmission system by lumped massparameter method is created, and its dynamic equations are derived inconsideration of tower flexible support, variable stiffness of gear meshing andmeshing error and so on.The dynamic response of the gear and drive shaft is obtained throughinstances of1.5MW wind turbine utlizing above transmission equations, whichare compared and analyzed. Impact parameters of transmission dynamicsequations are discussed. The influence of helix angle about the helical gear ontransmission dynamic response is analyzed and its law is given. The resultscould offer some reference value to wind turbine power transmission system design theory in China.