Progressively-censored aging tests on XLPE-insulated cable models

Abstract

The problem of evaluating the time-to-failure percentiles in progressively-censored tests on solid insulating materials is addressed. Statistical methods to estimate the parameters of the Weibull distribution (and their confidence limits) are examined on the basis of the results of aging with combined thermal-electrical stresses carried out on XLPE insulated cable models. These tests are performed at the same stresses on samples more than 1 m long and subjected to progressive censoring of aging times, or on short specimens about 20 cm long and subjected to complete, or singly-censored, life tests. This procedure allows the effectiveness of progressively-censored tests in estimating life percentiles to be verified, and the accuracy of the methods to be compared.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>