Quantitative evaluation method for transformer insulation cardboard aging based on dielectric response characteristics

Abstract

The present invention relates to a transformer insulating cardboard aging quantitative evaluation method based on dielectric response features. The main technical features of the method comprise the steps of: performing oil extraction of a tested transformer, and transmitting oil sample test objects to a lab for test; performing field transformer dielectric spectrum measurement; calculating a dielectric loss factor of the transformer under a special frequency; measuring dielectric spectrums of different insulating paper test objects through a frequency domain response dielectric spectrum testmethod; establishing an XY model, and calculating the whole dielectric spectrum of transformers with different aging degrees; fitting a relation of the transformer dielectric loss factors under the special frequency and the insulating cardboard aging degrees; and calculating the insulating cardboard aging degree. The method provided by the invention is reasonable in design, convenient to measure and calculate and accurate in result, achieve the quantitative evaluation function of the transformer insulating cardboard aging condition in a condition without hoisting cover sampling, is helpful formaintenance, test and repairing personnel to accurately grasp the operation state of the transformer and achieves accurate analysis and device management functions.

Description

technical field [0001] The invention belongs to the technical field of transformer testing, in particular to a method for quantitatively evaluating the aging of transformer insulating cardboard based on dielectric response characteristics. Background technique [0002] Oil-paper insulation system is the main insulation structure of oil-immersed transformers. In the oil-paper insulation system, since the samples of insulating oil are easy to obtain and the analysis technology of insulating oil is mature, the aging of insulating oil can be easily measured. However, the insulating paper is fixed inside the transformer, and the only way to obtain insulating paper samples is through hanging covers, hanging cores, etc., which is time-consuming and laborious. At the same time, the aging of insulating paper has a major impact on the safe operation of transformers. During the aging process, the degree of polymerization and tensile strength of insulating paper will gradually decrease...

AI Technical Summary

Problems solved by technology

Most of these aging products are harmful to electrical equipment, which will reduce the breakdown field strength and volume resistivity of the insulating paper, decrease the tensile strength, increase the dielectric loss, and even corrode the metal materials in the equipment.

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