Method for evaluating insulation aging state of crosslinked polyethylene cable

Abstract

The invention relates to a method for evaluating an insulation aging state of a crosslinked polyethylene cable. The method comprises the following steps that a to-be-detected cable sample is selected;the cable sample is sliced axially to obtain sample pieces; the sample pieces are subjected to ultrasonic cleaning and make contact with electrodes; the sample pieces are subjected to dielectric losstest, and the dielectric loss is detected; and according to a dielectric loss result, the cable aging degree is judged. According to the method, design is reasonable, the functions of detecting and evaluating a major insulation aging state of an in-service cable are achieved through a dielectric loss test method of the cable sample pieces, the test result has better guiding significance to transformation and maintenance of a cable line, the cable operation and maintenance management level can effectively improved, safe operation of the cable line is ensured, and the method has the advantagesof easy and convenient operation, cost saving and the like.

Description

technical field [0001] The invention belongs to the technical field of cross-linked polyethylene cables, in particular to a method for evaluating the insulation aging state of cross-linked polyethylene cables. Background technique [0002] Compared with overhead lines, power cables have the advantages of less land occupation and better insulation performance, and have become the main artery of urban power grids. XLPE insulated cables have been used for more than 30 years and have developed rapidly. They have simple structure, light weight, good heat resistance, strong load capacity, chemical corrosion resistance and high mechanical strength, excellent processability and low cost. Cost has made XLPE the preferred choice for cable insulation. [0003] With the prolongation of cable service time, the breakdown fault caused by the decrease of cable insulation performance occurs from time to time. Studies have shown that cable insulation will age under the continuous action of ...

AI Technical Summary

Problems solved by technology

However, the physical and chemical analysis method in the laboratory is still being explored and studied. The test object is a cross-linked polyethylene test piece extruded by a vulcanizing machine. The artificial accelerated aging method is used to conduct physical and chemical analysis tests on the test piece to evaluate the insulation performance of the material. The main problem is: the test object is not the cable running in the field, and the artificial accelerated aging is not equivalent to the field running conditions, so the test analysis results cannot effectively evaluate the actual running cable