Reliability assessment method for thermal aging state of transformer insulation based on mixed Weibull distribution

Abstract

The invention discloses a transformer insulation thermal ageing state reliability evaluation method based on Weibull distribution. The transformer insulation thermal ageing state reliability evaluation method comprises the following steps: 1, collecting paper oil insulation thermal ageing characteristic data; 2, establishing a reliability evaluation index system; 3, determining comprehensive weights of all indexes; and 4, constructing a reliability evaluation hybrid Weibull distribution model, and evaluating a paper oil insulation thermal ageing state. According to the transformer insulation thermal ageing state reliability evaluation method, a reliability evaluation index system is established by analyzing the sensitivity of each paper oil insulation thermal ageing characteristic parameter to the thermal ageing state, and the paper oil insulation thermal ageing state reliability evaluation is performed by integrating the data and the weights of all the indexes. Compared with an existing paper oil insulation thermal ageing state evaluation method in the aspects of parameters such as the insulation paper polymerization degree and the content of furfuraldehyde in oil, the transformer insulation thermal ageing state reliability evaluation method has the advantages that the influence of the reliability of all the indexes to the overall reliability of paper oil insulation can be more sufficiently considered, and thus relatively accurate paper oil insulation thermal ageing reliability values can be obtained, and the accuracy rate of monitoring and evaluating the insulation ageing state of an oil immersible power transformer is effectively improved.

Description

Technical field [0001] The invention belongs to the technical field of transformer insulation aging state evaluation, and in particular relates to a method for evaluating the reliability of transformer insulation thermal aging state based on a hybrid Weibull distribution model. Background technique [0002] The aging life model of high-voltage electrical equipment insulation materials has always been one of the research hotspots of scholars at home and abroad. The oil-paper insulation aging state assessment technology is helpful to improve the safe operation level of power transformers. The oil-paper insulation life evaluation model mainly includes two research methods: a) Fitting the oil-paper insulation accelerated aging test data to obtain the life evaluation model; b) According to the physical and chemical properties of oil-paper insulation aging, combined with space charge, partial discharge, etc. to analyze the insulation Damage mechanism, and verify the life evaluation mo...

AI Technical Summary

Problems solved by technology

The thermal aging parameters of oil-paper insulation directly or indirectly characterize the aging state of insulation, but due to the differences in the information contained in each parameter index and the errors caused by measurement methods, it is difficult to accurately evaluate the thermal aging state of oil-paper insulation.

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