Research On Reliability Accelerate Life Testing For Single-phase Smart Meter

Single-phase smart meter as a key part of State Grid, the reliability of which will not only impact the running of the Smart Grid, but also relate to the vital interests of the residents. However, there hasn’t been complete system for the comprehensive analysis of the reliability on the smart meter till now. In this paper, an accelerated life testing method on single-phase smart meters is developed, which mainly include the discussing on testing methods designing and life data statistical analysis.Based on the characteristics of the single-phase smart meter, smaller single units can be subdivided, which can be more conveniently to define the failure of single-phase smart meter. Combining with the results of historical data and environmental impact analysis results, we find the main sensitive stresses which influence the reliability of single-phase smart meter are the high-temperature stress and the over current stress. Then the high-temperature, humidity and current reliability enhancement testing are developpde, from which we can stimulate the failure modes and make sure the operating limit and destruct limit, according which the safe stress rage of the accelerate testing and the testing items can be ensured. Through a further analysis, we set three stresses combination [55℃,20A]、[70℃40A]、[80℃,60A] under the step-stress time censoring accelerate testing, at last the sample size,testing cut-off conditions and failure criterion on the limit of testing condition are confirmed.Above all, the testing scheme is finished.The accelerate life testing is started flowing the testing scheme, dealing with the degradation date in the testing, the regression analysis method and least square method are choosed, which is in order to get the degradation locus equation of every sample under all stresses combination levels,and then estimate the product fake failure life. Based on the theory of the accelerate life testing, a relationship between different stresses level and fake failure life will be established, according which the life distribution parameter under normal environmental can be estimated. statistics analysis results showing that the reliability of single-phase smart meter in normal environment after10years can be reach0.688, which shown that the level of single-phase smart meter is optimistic.