Reliability Analysis Of 2.5MW Wind Turbine Gearbox With Three Grade Transmission

Wind power generation is an important source of environmental friendly energy,in recent years,wind power generation has become more and more important.It has become the world's fastest growing new energy.Wind energy is also the cheapest renewable energy.The wind does not need any fuel,so it has no waste problem;The wind does not produce radiation or carbon dioxide pollution;The wind will not affect the ecological environment,atmospheric climate and geological disasters,and has less impact on the environment.many countries have plans to invest in wind power in the near future.Wind turbines are mostly installed in remote areas such as sea,mountain,desert and so on.As a result,each gust impact on a wind turbine can be observed with a fast and robust change in electrical output power.These load changes require not only a stable grid to make it stable,but also a reliable mechanical part and system to withstand the stress generated during the load changing.Therefore,in order to design high reliability mechanical structures,especially in high power,design and manufacturing costs will become expensive.Data show that 12% of the world's wind turbine fault from the gearbox.In the wind power gearbox parts,gear failure rate of up to 60%,gear failure caused by wind turbine downtime,resulting in greater losses.Therefore,analyzes the strength and reliability of the gear,and provide a theoretical basis for the design and manufacturing engineering,so as to reduce the failure rate is extremely important gear.This paper aims at a gearbox company's existing 2.5 MW gearbox as the research object,the 3D model of three stage gear in wind power gearbox is established by Solidworks software,And then assembly;Using Solidworks and finite element software ANSYS docking interface,3D model is introduced into the finite element software,define the material properties,meshing,setting contact,applying loads and constraints,and analyzing the thermal structure coupling dynamics;The equivalent stress and temperature of all gears are obtained by simulation;Based on the discreteness of material properties,Random wind load and uncertainty of tooth surface friction coefficient,Six sigma analysis in ANSYS Workbench,and then extract the probability density distribution of stress and temperature;Finally,the reliability of strength failure and scuffing failure under two kinds of correlation failure are calculated by Copula function correlation theory.