| The vibration characteristics of the wind turbine directly affect the reliability operation of the unit.In order to obtain the vibration characteristics of the wind turbine drive system,this paper focuses on the vibration theory,the torsional vibration modeling method and calculation method,and the dynamic response calculation and analysis of the planetary gear system.The details are as follows:(1)The dynamics theory and calculation method of wind turbine drive system are studied and summarized.Based on the simplified model of lumped parameter method,the vibration differential equation of the system is established.The calculation method of vibration is verified by a numerical example.It lays the foundation for calculating the inherent characteristics of the torsional vibration of the transmission drive system and the calculation of the transient response.(2)Considering the influence of aerodynamic load and electromagnetic torque of grid fault: the wind speed model based on wind shear effect,tower shadow effect and turbulence effect predicts the aerodynamic load excitation force;based on the twophase short circuit at the generator exit Three-phase short circuit,120° nonsynchronous grid-connected fault and 180° non-synchronous grid-connected faulty empirical formula,using MATLAB programming to obtain electromagnetic torque under different grid faults.It provides a way to obtain the external excitation force of the drive train.(3)Calculation of transient torsional vibration characteristics of wind turbines: 5MW offshore direct drive wind turbines and 750 kW land doubly-fed wind turbines were used as research objects,and the torsional vibration calculation of wind turbine drive system was established by lumped parameter method.Based on the analysis model,the basic flow of torsional vibration analysis of wind turbines is summarized.Based on the idea of solving the characteristic equations of homogeneous differential equations,the inherent characteristics of torsional vibration of the transmission system are obtained by MATLAB programming.The unconditionally stable Newmark-? method is used to solve the model.The maximum dynamic response amplitude of the transmission system shaft segment of the transmission system under random wind loads and electromagnetic torque.(4)Research and application of calculation method for vibration response of wind turbine gear system: Considering the influence of key factors of gear transmission system(internal excitation and external excitation,etc.),the analysis of four-degreeof-freedom planetary gear system based on lumped parameter parameters is established.The model is used to analyze the vibration response characteristics of the planetary gear system of 750 kW wind turbine under different excitations. |
PDF Full Text Request