分布式发电系统中电热疲劳器件的健康状态估计及其剩余寿命预测

In distributed generation systems, electrothermal fatigue devices associate with the temperature rise in operation so that fatigue accumulates fast. The damage degree of them mainly depends on the accumulation of thermal damage intensity with time, which is temperature-related. Therefore, remaining life of the kinds of devices is related with applied electrical stress, temperature, performance and the enlistment age. The main contents of this project are as follows: 1) Research the timing mode of curved surfaces about the relation between double stress sequence and temperature sequence. And then research the calculation of electrothermal fatigue characteristics. 2) Consider time-lag of electrothermal effect and develop the quantitative estimation of health condition based on statistical properties of electrothermal fatigue characteristics. 3) Study the cloud uncertainty of health condition, elplore timing sequence mode of devices under operation cycles of systems and research health condition prediction according to cloud model based on the trend of the numeral characteristics of cloud properties. 4) Research the formulation and the prediction about remaining life in the light of the cloud uncertainty of health condition and realize the prediction of remaining life for the devices in the following operation cycles. Check and detect the devices which are too fatique to work normally in next system operation cycle and replace them in advance. It will contribute to guarantee the safety and reliability of generation system, especially to the systems which are multi-malfunction in their late-stage service.

分布式发电系统中的电热疲劳器件，在运行中伴发温升，疲劳累积快，其损伤程度取决于与温度有关的热损伤强度对时间的积累，其电热效应取决于疲劳程度。因此这类器件的剩余寿命与电应力、温度、性能均相关。 本项目研究的主要内容：1)研究双应力-温度序列相关曲面时序模态的发现方法和电热疲劳特征量的计算方法；2)基于电热疲劳特征量的统计特性，考虑电热效应时滞性，研究健康状态定量估计方法；3)研究健康状态的云不确定性，发现系统运行周期内的健康状态时序模态，研究基于云属性数字特征趋势性的健康状态云不确定性预测方法；4)研究基于健康状态云不确定性剩余寿命表述方法和预测方法，实现系统后续运行周期的器件剩余寿命云预测。 检修发现虽正常工作但剩余寿命不足一个运行周期的器件，并提前更换，特别有助于保证服役后期故障多发的发电系统的运行安全及可靠性。

分布式发电系统中的电热疲劳器件，在运行中伴发闻声，疲劳累积快，其损伤程度取决于与温度有关的热损伤强度对时间的积累，其电热效应取决于疲劳程度。这类器件的剩余寿命与电应力、温度、性能均相关。因此，本项目针对电热疲劳器件的健康状态估计及剩余寿命预测展开研究。进行了电热疲劳器件温度场仿真，发掘应力-温度相关性并进行电热疲劳分析；设计并搭建电热疲劳测试试验系统，包括三相逆变试验系统，加速退化试验及电热特性试验；发现电热疲劳征兆并定义电热疲劳特征量；研究健康状态隶属关系的获取方法，对电热疲劳器件建立健康状态估计模型；建立了基于云模型的剩余寿命预测模型，建立了考虑退化状态的剩余寿命预测模型。本项目研究成果可应用于IGBT模块及电热疲劳器件，以进行健康状态估计及剩余寿命预测。