中文摘要：

功率变流器是风机系统的核心组件,其可靠性受风机系统的功率波动影响,因此风电变流器的可靠性评估应考虑长时间任务剖面的影响。然而现有器件可靠性评估方法受限于结温计算方法,难以准确而快速的评估功率器件的寿命。因此文中在分析基于组件可靠性手册和基于失效机理的功率模块可靠性评估方法的基础上,对风电变流器长时间任务剖面进行尺度划分,提出一种功率模块的多时间尺度寿命评估方法。文中以1.2 MW直驱风力发电系统为例,利用器件结温数值计算方法,结合实际风速和气温数据快速计算出器件的多尺度任务剖面,基于文中提出的器件寿命评估方法计算了功率模块的寿命消耗,分析了多时间尺度任务剖面对功率模块寿命消耗的影响,并对研究结论进行了深入讨论。文中结论还为研究提高风电变流器中功率器件寿命的措施提供了一种新的思路。

英文摘要：

Power converters are crucial components of the wind turbine generator system（WTGS）, and reliability of wind power converters is susceptible to power fluctuations of the WTGS. Lifetime estimation of power semiconductors should consider the long-time mission profiles of wind power converter. The existing reliability evaluation methods of power devices are limited by the junction temperature calculation method, and difficult to evaluate the lifetime consumption of power devices accurately and rapidly. On the basis of analyzing the lifetime estimation methods of devices based on the component reliability handbook and the failure mechanisms of power devices, this paper proposes the multi-time sale lifetime evaluation method of power modules in the wind power converter. A 1.2MW wind energy conversion system is regarded as a case study, and the multi-time sale mission profiles of power devices are quickly calculated by the junction temperature calculation method considering the actual wind speed and air temperature. The multi-time sale lifetime consumption of devices are evaluated, and the effect of multi-time sale mission profiles of power devices on lifetime consumption is analyzed. Finally, the conclusions are deeply discussed in this paper. This paper also presents a new idea for researching the measures of improving the lifetime of power devices.