中文摘要：

功率变流器是风机系统的核心组件，其可靠性直接影响风电系统的可靠性。风电变流器中主要的失效部件是IGBT模块，因此对IGBT模块进行寿命预测可以提高整个风电系统的可靠性。首先讨论变流器电热耦合模型中的退化参数，然后基于LESIT寿命预测模型和雨流循环计数法提出考虑IGBT模块退化状态的寿命预测方法。文中以1.2MW风力发电系统为例，预测了网侧风电变流器中IGBT模块的寿命，并对比分析了是否考虑模块的退化状态对寿命预测结果的影响。

英文摘要：

Power converter is a crucial component of the wind turbine generator system,and its reliability influence the reliability of the wind power system directly.The IGBT module is the main possible failure part in the wind power converters,sopredicting the lifetime of IGBT can improve the reliability of the entire wind power system.The degradation parameters of theconverter electro-thermal model are discussed.The lifetime prediction method considering the degradation state of IGBT is proposed based on the LESIT model and rain-flow cycle counting method.A1.2MW wind energy conversion system is taken as astudy example,the lifetime of IGBT module in grid side converter is predicted,and the two lifetime prediction results whichconsiders and does not consider the degradation state are compared.