The Study On Dynamic Characteristics Of Gear Transmission System Of Wind Turbine Under Variable Loads

Wind power generation as a kind of clean and renewable energy has attractedincreasingly attention and the wind power technology has developed quickly. Whenwind turbine running, the rotor speed is far below the speed required by the powergeneration, thus the use of growth rate of gear transmission box is to achieve movementand the power transmission between the wind wheel and generator. The growth rate ofgear transmission box as an important component of the wind turbine, working in theharsh environment of the complex variable loads and at high altitude erected state andmaintenance in-convenience, has strict requirements on the operational stability andreliability. Research on the dynamics of wind turbine gear transmission under variableload conditions is one of the important task of design and manufacture of wind turbinegearbox.This thesis, aided by the National Natural Science Fund, considering the influenceof random wind and generator to the gear transmission system, wind turbines threehelical gear drive system as the study subject, studied on the dynamic characteristics inlow-speed shaft torque of pneumatic and high-speed axis electromagnetic torque in. Thethesis content mainly includes:First, based on mathematical model of a random wind speed, aerodynamicperformance, the drive chain and a squirrel cage induction generator, and correspondingsimulation model in Matlab, considering the case of the control strategy at low windspeed conditions and high wind speed conditions respectively simulation and analysis ofdynamic external load, to obtain the transmission system of the low speed shaft andhigh speed shaft of the dynamic variation of the external load;Second, considering the low speed shaft aerodynamic load, high speed shaftelectromagnetic torque, time-varying mesh stiffness, meshing error and damping factorsfocus on the quality of three helical gear system dynamics model of pure torsion, derivethe system vibration differential equations and analysis of the gear system of internaland external incentives;Third, variable-order numerical differentiation algorithm for solving dynamicdifferential equations of the gear system under the dynamic external loads conditions ofthe aerodynamic torque and induction generator electromagnetic torque, obtain the gearvibration displacement, dynamic meshing force and the vibration velocity of the meshing pair of the gear system under internal incentives and external incentives andanalysis the dynamic characteristics of the gear transmission system.Above work provides a theoretical reference for design and manufacture of windturbine gear transmission system.