Dynamic Modeling And Characteristic Analysis Of Yaw System On Wind Turbine

Multi-source driving yaw system is widely used in large-scale wind turbines.However,due to the complex coupling effect of mechanical、electrical and hydraulic,the dynamic process and behavior characteristics of multi-source driving yaw system of wind turbines need to be further studied.Therefore,through the combination of theoretical analysis,numerical simulation and field data analysis,this paper proposes the correction algorithm of large-scale wind turbine yaw load calculation,carries out the finite element analysis of multi-source driving yaw gear transmission system,constructs the dynamic model of multi-source drive yaw system of large-scale wind turbine,and analyzes its dynamic behavior The vibration characteristics of large-scale wind turbine under yaw are analyzed,and the understanding of yaw system and its behavior characteristics of large-scale wind turbine is deepened.The followings is main parts and innovations of this paper:（1）The yaw load calculation model of large-scale wind turbine is constructed.Firstly,the multiple load sources of large wind turbine blades（including aerodynamic force,gravity force,inertial force,etc.）are analyzed,and the yaw load calculation model is constructed when the wind direction is perpendicular to the wind turbine.Then,the influence of wind direction deflection（yaw angle）on yaw load is analyzed,and the relationship between yaw angle and yaw load is established through regression analysis,thus an approximate calculation model of yaw load is obtained,which provides a load basis for the analysis of dynamic characteristics of yaw system.（2）The finite element analysis of multi-source driving yaw gear transmission system of large-scale wind turbine was carried out.Firstly,a three-dimensional solid model of multisource driving yaw actuator（including yaw motor-gearbox yaw pinion-yaw inner gear ring）is established by using Solid Works software,and the meshing stiffness of multi-stage gear is calculated in ANSYS Workbench.Then,the stress-strain characteristics of single point（source）driving and multi-point（source）driving are analyzed,and the stress-strain characteristics of gear crack are further analyzed.（3）The dynamic analysis model of large-scale wind turbine multi-source driving yaw system is constructed.The multi-source drive yaw system is divided into yaw driving motor subsystem,multi-stage driving subsystem and hydraulic brake subsystem.The models of each subsystem are established and integrated respectively.The dynamic characteristics of the yaw system under two control strategies（yaw angle comparison control and yaw angle servo control）are analyzed,and then the multi-source driving yaw system model is integrated into the wind turbine model,and the dynamic characteristics of yaw system on wind turbine are analyzed.（4）Based on SCADA（Supervisory Control and Data Acquisition）data,the vibration characteristics of large wind turbine under yaw condition are analyzed.Based on the SCADA data of a wind farm in one year,the distribution characteristics of wind speed and direction in the local wind farm are analyzed,and the yaw running times of wind turbine is counted monthly.Then,according to the wind speed,the low wind speed,rated wind speed and high wind speed are classified and the vibration characteristics of wind turbine in front and back direction,left and right direction are analyzed respectively,so as to deepen the understanding of the yaw process of wind turbine.