A Method for Evaluating the Degree of Uneven Wetting of Oil-impregnated Paper Insulation Assemblies

Abstract

The present invention provides a method for evaluating the degree of uneven dampness of an oil-impregnated paper insulation assembly, comprising: step S1, forming a plurality of oil-impregnated paper samples with uneven dampness through a plurality of uniformly damp oil-impregnated paper insulation samples, and evaluating each The oil-impregnated paper sample is subjected to a frequency-domain dielectric spectrum test to obtain a plurality of first dielectric spectrum curves, and the corresponding relationship between each first dielectric spectrum curve and the degree of moisture of each oil-impregnated paper sample is established; step S2 , performing a frequency-domain dielectric spectrum test on the actual oil-impregnated paper insulation assembly to obtain a second dielectric spectrum curve, when the similarity between the second dielectric spectrum curve and one of the first dielectric spectrum curves meets a predetermined requirement , the degree of dampness corresponding to the corresponding first dielectric spectrum curve is taken as the degree of dampness of the actual oil-immersed insulation component. The invention has the advantages that: the characteristic peak of the frequency domain dielectric spectrum is used to evaluate the uneven moisture content of the oil-paper insulation, which improves the accuracy of the moisture evaluation of the oil-paper insulation compared with the existing method, and can obtain more detailed moisture conditions.

Description

technical field [0001] The invention relates to the technical field of power transmission detection, in particular to a method for evaluating the degree of uneven dampness of an oil-immersed paper insulation assembly. Background technique [0002] Oil-impregnated paper insulation is one of the most commonly used insulating materials for power equipment. It is mainly used in the insulation system of oil-immersed transformers, oil-impregnated paper bushings and oil-immersed capacitors. In the power grid system of 110kV and above, the proportion of oil-impregnated paper insulation reaches more than 93%. Among them, the capacitive high-voltage bushing is one of the typical oil-impregnated paper insulation devices, and it is an indispensable external connection component of the power transformer. It not only has the function of leading the winding leads out of the transformer, but also bears the role of supporting and fixing the leads. The data show that the bushing accidents o...

AI Technical Summary

Problems solved by technology

The first two measurements must take samples to destroy the insulation of the equipment. The weighing method has been replaced by the Karl-Fisher method because of its low measurement accuracy.

The oil-soaked paper moisture balance curve method first measures the moisture content in the oil, and then estimates the water content in the paper according to the oil-soaked paper moisture balance curve. This method is easy to operate and will not damage the equipment insulation, but the measurement accuracy is low

Images