基于 Copul a函数的2.5 MW风电齿轮箱齿轮可靠性分析

摘要

针对2.5 MW风电齿轮箱齿轮可靠性分析时，需考虑其接触疲劳和弯曲疲劳失效的相关性问题，根据风场长年监测数据，利用雨流计数法得到了其载荷谱，利用Romax Designer软件建立了2.5 MW风电齿轮箱的传动系统模型；利用其齿轮部件分析模块计算并统计得到了各齿轮的接触应力与弯曲应力分布；应用应力—强度干涉模型并基于Copula函数建立了考虑接触疲劳和弯曲疲劳相关性的齿轮疲劳可靠性计算模型；应用蒙特卡罗法对应力和疲劳强度抽样，并利用离差平方和最小值原理和MATLAB优化工具箱估计了Copula函数的参数，并计算出各齿轮的疲劳可靠度．研究结果为改进2.5 MW风电齿轮箱设计、提高其可靠性提供理论依据．%In order to research gear reliability of 2.5 MW wind turbine gearbox considering relativ‐ity of contact fatigue and bending fatigue ,based on the many years monitoring data of experiment wind load ,the Load Duration Distribution (LDD) was determined with the Rain‐flow Method . The transmission system model of 2.5 MW wind turbine was obtained based on Romax Designer software .Contact stress and bending stress were calculated by taking LDD into the transmission system model .So the distribution of contact and bending stress were determined with statistic method .Based on the Copula function the gear reliability calculation model which took the corre‐lation of contact and bending fatigue into consideration was determined under the dependency be‐tween contact fatigue and bending fatigue with the use of stress‐strength interference model . Stress and fatigue strength sampling was generated by Monte Carlo sampling method .Copula function parameter was estimated by Residual Square Sum (RSS) and optimized by MATLAB toolbox .Then each gear fatigue reliability was calculated .It provides the theoretical basis to im‐prove the reliability of 2.5 MW wind turbine gearbox .