关键字：POWER-CABLES; WATER

摘要：Moisture is one of the major factors for the internal insulation damage of cable and accessories during operation. In this paper, the influence of moisture on the insulation properties of cable and accessories is investigated, and the harmonic technique is used to analyze the harmonic characteristics. Firstly, the insulation properties of cross-linked polyethylene (XLPE), ethylene-propylene-diene (EPDM) and silicone rubber (SIR) under different moisture time are compared for volume resistivity, dielectric constant and breakdown strength. Further, the influence of moisture time on the harmonic characteristics of single and composite dielectric (XLPE/EPDM, XLPE/SIR) is studied. Finally, the moisture mechanism of insulation dielectric is researched. The results show that the volume resistivity, breakdown strength and flashover voltage of the three single dielectric decrease with the increase in moisture time, and the XLPE decreases the most seriously, which decreases by 82.76%, 25.73% and 17.11%, respectively, compared with the untreated dielectric. The relative dielectric constant is the opposite, in which XLPE has the largest increase, reaching 21.66%. Under the same moisture time, the third, fifth and ninth harmonics of single and composite dielectric are typical harmonics, and the third harmonic content is the highest. With the increase in moisture time, the ninth harmonics of XLPE and EPDM sample change obviously, and the third harmonics of SIR sample and XLPE/EPDM and XLPE/SIR composite material increase significantly. This work has important guiding significance for the operation and maintenance of insulation moisture of distribution cable and accessories.

卷号：107

期号：2

是否译文：否