Electrical treeing test device and sample making method of silicone rubber material for cable accessories

Abstract

Electric branch test device and sample preparation method of silicone rubber material for cable accessories, adding semi-conductive silicone rubber into xylene, then spraying on the surface of the silicone rubber insulation sample, curing, and then cutting into a triangular high-voltage at the end of the longitudinal section electrode, and then paste the high-voltage electrode on the surface of the silicone rubber insulation sample, and vulcanize at high temperature to obtain the piezo electrode silicon rubber sample; put the piezo electrode silicon rubber sample into the mold, inject glue, and vulcanize at high temperature to obtain the sample; then Cut off the tip of the high-voltage electrode at 2 mm, and paste the flat-plate structure ground electrode on the cross-section. With the sample of the present invention, air gaps and cracks will not appear at the tip of the high-voltage electrode under large mechanical deformation. Moreover, the electrical branches in actual cable accessories usually develop from semi-conductive to insulating parts, and semi-conductive materials used as high-voltage electrodes are more similar to the actual working conditions of cable accessories.

Description

technical field [0001] The invention relates to an electric tree branch test device and a sample preparation method of silicone rubber materials used for cable accessories, and belongs to the technical field of research on the electric tree branch resistance performance of insulating materials. Background technique [0002] As the production technology of high-voltage power cables and accessories in my country becomes more and more mature, high-voltage cables gradually replace overhead lines as the main channel for power transmission in cities, and the consumption of cable accessories also increases. Cable accessories are the most vulnerable link in the power system. 70% of power system failures are caused by the failure of cable accessories. The mainstream view is that the electrical branches inside the accessories are the main reason for the failure of cable accessories. At present, the installation of cable accessories mostly adopts prefabricated structures. Silicone rubb...

AI Technical Summary

Problems solved by technology

Since the silicone rubber material is a superelastic material with low tear strength, the steel needle as a high-voltage electrode is prone to cracks and air gaps at the needle tip under the action of large mechanical deformation, and even tears the sample from the needle tip, which seriously affects the test. result

Individual researchers used steel needles to make silicone rubber samples with a needle-plate electrode structure, and studied the initiation and growth characteristics of silicone rubber electrical trees under compressive force and tensile deformation, but the maximum stretching ratio is 30%. Far lower than the expansion rate of about 45% of common high-voltage cable accessories, it cannot reflect the characteristics of electrical branches under the actual deformation size of cable accessories, and it is difficult to realize the test of large mechanical deformation

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