부산대학교 도서관

This paper presents Weibull failure models by experimental work and the step-up accelerated electrical–thermal test of oil-impregnated paper with 0.2 mm thickness is carried out under pulsating DC voltage at different temperatures. The breakdown voltage and failure time of the oil gap–paper insulation specimens at the same voltage duration is obtained by accelerated electrical–thermal aging test. The Weibull failure models of three-variable oil gap–paper insulation modified by Fallou and Ramu are established to analyze the failure data of oil gap–paper under different electric field intensities and temperatures. The statistical test method was used to evaluate the applicability and accuracy of two modified triple-variables Weibull failure models. The comprehensive test index of the Fallou-modified WFD is 1.6851, and the comprehensive test index of the Ramu-modified WFD is 1.8124. The Fallou-modified results were more accurate than Ramu-modified results in estimating the statistical distribution of failure data. Results show that the proposed triple-variable Weibull failure model could fully reflect the insulation state of oil gap–paper under the action of electric and thermal fields.