XLPE cable water tree accelerated aging tester and sample manufacturing method

Abstract

The invention relates to the field of cable aging testing and particularly discloses an XLPE cable water tree accelerated aging tester and a sample manufacturing method. The tester comprises a voltagegeneration monitoring unit and an XLPE cable sample unit and is characterized in that the XLPE cable sample unit comprises a heat-shrinkable sleeve, a NaCl solution and an XLPE cable; the heat-shrinkable sleeve sleeves the XLPE cable, two ends of the heat-shrinkable sleeve are connected with two ends of the XLPE cable in a sealed manner, a gap exists between the middle of the heat-shrinkable sleeve and the XLPE cable to form a cavity, the cavity is filled with the NaCl solution, and the upper portion of the cavity is provided with a liquid injection hole; the outer semi-conductive layer of the XLPE cable located in the NaCl solution is provided with a plurality of defect needle holes, the power supply end of the voltage generation monitoring unit is connected with the core of the XLPE cable, and the grounding end of the voltage generation monitoring unit extends into the NaCl solution. By the tester, the water tree aging process of the cable in actual operation can be effectively simulated.

Description

technical field [0001] The invention belongs to the field of cable aging test devices, in particular to an XLPE cable water tree accelerated aging test device and a sample preparation method. Background technique [0002] Driven by the great development of power technology, power cables have been widely used in power plants, substations, power leads or lead-in lines of industrial and mining enterprises, and urban power transmission and distribution networks. In the development history of the cable industry for more than a hundred years, oil-paper insulated power cables have played an important role. However, with the advancement of insulating material technology, cross-linked polyethylene (XLPE) insulated power cables have And the mechanical properties have been developed rapidly. At the same time, it has the advantages of large transmission capacity, light structure, no height drop restrictions, no oil leakage and fire hazards. In urban power grid reconstruction and constru...

AI Technical Summary

Problems solved by technology

[0003] The design life of XLPE cables is 30 to 40 years. However, due to the moisture intruding into the cables during production, transportation, and installation, the air gaps and impurities inside the XLPE insulation layer, and the burrs on the contact surface between the semiconductive layer and the insulation layer, etc. Due to the influence of electrical defects, after the cable is put into operation, the electric field will be concentrated in the corresponding area, which is prone to water tree aging. With the increase of the operating life, the high field strength will promote the water tree to gradually develop along the direction of the electric field, and eventually develop into an electric tree branch , leading to insulation breakdown failure of the cable, seriously affecting the safe and stable operation of the cable line

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