Cable buffer layer axial resistivity test device and test method

Abstract

The invention discloses a cable buffer layer axial resistivity test device, which is characterized in that a first voltage test electrode, a second voltage test electrode, a first current test electrode and a second current test electrode are embedded and fixed in a lower insulation pressing block, and the first current test electrode is located at the outer side of the first voltage test electrode; the second current test electrode is positioned on the outer side of the second voltage test electrode; the cable buffer layer sample is located between the upper insulation pressing block and thelower insulation pressing block; the first voltage test electrode, the second voltage test electrode, the first current test electrode and the second current test electrode can make contact with the semi-conductive non-woven fabric layer of the cable buffer layer sample, and one end of the direct-current power source is connected with the first current test electrode through the ampere meter. Theother end of the DC power supply is connected with the second current test electrode, one end of the voltmeter is connected with the first voltage test electrode, and the other end of the voltmeter isconnected with the second voltage test electrode. According to the invention, the axial resistivity of the cable buffer layer can be rapidly and accurately tested.

Description

Technical field [0001] The invention relates to the technical field of electrical testing, in particular to a testing device and a testing method for the axial resistivity of a cable buffer layer. Background technique [0002] High-voltage XLPE cables have been used in my country for more than 30 years, and they have basically achieved localization. Every year, more than 10,000 kilometers of high-voltage cables are buried underground. During the migration, reconnection, and fault analysis of high-voltage cables in the past ten years, a large number of "ablation" and "white spots" have been found on the surface of the buffer layer and insulation shield. Analysis of the cause of the failure is related to the change in the resistance of the cable buffer layer. As national standards have not yet specified the method for measuring the resistivity of the cable buffer layer, the measurement methods in the project are not uniform and the measurement data is inaccurate. The cable buffer...

AI Technical Summary

Problems solved by technology

Since the national standard has not stipulated the measurement method of the resistivity of the cable buffer layer, the measurement method in the project is not uniform and the measurement data is inaccurate

The cable buffer layer is a semi-conductive material, and the conventional voltammetric method does not distinguish the voltage and current loops when measuring the resistance of the cable buffer layer. The measurement error caused by the contact resistance is relatively large, which cannot reflect the real resistivity of the cable buffer layer.

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