高干热环境下计及竞争失效的电能表可靠性评估方法

Reliability Evaluation Method for Electricity Meters with Competitive Failures Under Arid High Temperature

典型环境下电能表寿命与可靠性评估是行业内亟待解决的热点和难点问题。针对高干热典型环境试验基地挂网电能表存在样本量小、突发失效和渐进失效并存的问题,在计及故障数据随机截尾的情况下构建了电能表可靠性经典和Bayes评估方法,将现场运行电能表的可靠性信息与高干热典型环境基地电能表的可靠性信息相融合以扩展信息量,提高电能表可靠性评估准确性。进而考虑到电能表计量性能存在多指标、渐进失效的情况,基于多元Wiener过程构建高干热环境下存在竞争失效模式的电能表可靠性综合评估模型,给出电能表可靠度、MTBF和可靠寿命三种可靠性指标的点估计与置信限。收集了新疆吐鲁番、乌鲁木齐和阿勒泰地区现场挂网运行数据和高干热典型环境试验基地内电能表数据,验证本文所提方法的有效性。研究成果不仅为解决了小子样多元竞争失效型产品可靠性评估提供了理论基础,在工程上也为电力计量行业借助典型环境试验基地开展量测设备可靠性评估提供了参考,其应用前景广阔。

How to carry out the research on the life and reliability of smart electricity meters(SEMs)with the help of typical environmental test bases is a hot and challenging issue in the current industry.In view of the problems of a small amount of failure time,sudden failure and degradation failure of SEMs in the typical environment test base of high dry heat,the classical and Bayes evaluation methods of SEMs reliability are constructed considering the random truncation of the fault data.The reliability information of SEMs in the field operation is combined with the reliability information of SEMs in the typical environment test base of high dry heat to expand the information content and improve the accuracy of SEMs reliability evaluation.Further,considering the multi-index and degradation failure of the metering performance of SEMs,a comprehensive evaluation method of the reliability of SEMs is constructed based on the multivariate Wiener process with competitive failure modes under high dry heat environment,and the point estimates and confidence limits of the three reliability indicators of SEMs are given,including reliability,MTBF and reliable life.The on-site gridconnected operational data from Turpan,Urumqi,and Altay regions in Xinjiang,as well as the data of SEMs collected from the high dry heat typical environmental test base,were utilized to verify the effectiveness of the method proposed in this paper.The research results not only provide a theoretical basis for solving the reliability evaluation of small sample multiple competitive failure products,but also provide a reference for the power metering to conduct reliability evaluations of measurement equipment with the aid of typical environmental test bases.The application prospects of this research are broad.