电工技术学报2025，Vol.40Issue(7)：2295-2305,11.DOI:10.19595/j.cnki.1000-6753.tces.240518
基于热解动力学的有机硅凝胶封装绝缘剩余寿命评估方法
Remaining Life Assessment of Silicone Gel Package Insulation Based on Pyrolysis Kinetics
摘要
Abstract
Power electronics is a prominent aspect and critical characteristic of the emerging power system,wherein power conversion equipment plays a vital role in facilitating energy conversion and delivery.The power electronic devices used in multi-energy conversion equipment are being designed to focus on high efficiency and power capabilities.Additionally,the high-frequency thermogenic effect is becoming increasingly prominent.As a result,the chip junction temperature typically reaches several hundred degrees.The silicone gel package insulation material is susceptible to aging and degradation while operating in high-temperature circumstances for extended periods,which can result in insulation failure.To solve this problem,this paper derives a microscopic pyrolysis kinetic characterization model for encapsulated insulation,proposes an efficient solution method for the three thermodynamic state parameters in the model,and then establishes a high-precision package insulation life assessment model. Firstly,this research presents a model that characterizes the kinetics of pyrolysis for silicone gels at a microscopic level.A link is established between the remaining life assessment and the temperature integral P(u),the pyrolysis activation energy E,and the insulation failure temperature Tf.Subsequently,a solution algorithm is provided to determine the model state parameters efficiently.The validation results demonstrate that the temperature integration algorithm proposed in this paper outperforms the existing temperature integration results across the entire integration interval.Additionally,the enhancement of the Flynn-Wall-Ozawa method leads to a 2%increase in the accuracy of the activation energy calculation.At the same time,the insulation failure temperature of the silicone gel sample is 453℃by the microscopic determination method,and the weight loss rate is only 3.4%,which is lower than the weight loss rate of 5%recommended by the national standard.This finding contributes to establishing a more rational criterion for life failure.The evaluation results indicate that temperature substantially impacts the package insulation.Specifically,for every 10℃rise in operating temperature,the insulation life decreases by around 60%.Finally,the accuracy of the life prediction model provided in this research is demonstrated by an accelerated thermal aging experiment using silicone gel. The following conclusions can be drawn from the experiments analysis:(1)Utilizing an enhanced temperature integration algorithm,a refined Flynn-Wall-Ozawa equation is formulated,resulting in a 2%enhancement in the precision of determining the activation energy of silicone gels compared to the conventional Flynn-Wall-Ozawa equation.(2)This study proposes a microscopic approach to determine the temperature at which insulation failure occurs in package materials.The results show that the silicone gel sample had insulation failure at a temperature of 453℃,with a weight loss of only 3.4%.(3)The evaluation results indicate that the temperature substantially affects the insulation of the package.The lifetime of the package decreases by approximately 60%for every 10℃increase in operating temperature.关键词
封装绝缘/热失重分析/活化能/寿命预测Key words
Package insulation/thermal weight loss analysis/activation energy/lifetime prediction分类
信息技术与安全科学引用本文复制引用
王伟,李贝,王健,任瀚文,李庆民..基于热解动力学的有机硅凝胶封装绝缘剩余寿命评估方法[J].电工技术学报,2025,40(7):2295-2305,11.基金项目
国家重点研发计划(2021YFB2601404)、国家自然科学基金(52177147,52127812)、北京市自然科学基金(3232053)和中央高校基本科研业务费专项资金(2023JC005)资助项目. （2021YFB2601404）
