交联纳米材料/聚乙烯复合型电缆绝缘性修复

Insulation Repair of Cross-linked Nano Material/Polyethylene Composite Cable

交联纳米材料/聚乙烯复合型电缆很容易出现水树、老化现象,导致发生绝缘性失效引起的击穿事故,进而影响电力传输的安全稳定性。设计交联纳米材料/聚乙烯复合型材料电缆绝缘性修复实验,并验证其效果。实验采用YJLV22-8.7/10kV-3*50 XLPE电缆,材料为交联纳米材料/聚乙烯复合型,在NaCl溶液中进行加速老化。采用水针电极插入的方法对电缆内部材料进行电荷注入,将修复液注入电缆内部,完成电缆材料的注入传导处理。为检测绝缘性修复效果,进行测试实验。实验结果表明,这种针对交联纳米材料/聚乙烯复合型绝缘电缆修复技术,修复一周后电缆整体的绝缘性能仍会逐渐增强,tanδ会不断下降。修复一个月后,电缆整体tanδ逐渐趋于稳定,绝缘电阻也逐渐趋于稳定,场强与附近电缆绝缘场强接近,抗水树性能增加,且介损及泄漏电流明显下降,耐压水平提升,更适合未来电网发展。

The cross-linked nano material/polyethylene composite cable was prone to water treeing and aging,leading to breakdown accidents caused by insulation failure,which could affect the security and stability of power transmission.The insulation repair experiment of cross-linked nano material/polyethylene composite cable was designed,and its effect was verified.YJLV22-8.7/10kV-3*50 XLPE cable was used in the experiment,and the material was cross-linked nano material/polyethylene composite type,which was accelerated aging in NaCl solution.The method of water needle electrode insertion was used to inject charge into the internal materials of the cable.The method of inserting water needle electrode was used to inject charge into the internal material of the cable,and the repair solution was injected into the cable to complete the injection and conduction treatment of the cable material.In order to test the effect of insulation repair,test experiments were carried out.The experimental results show that the overall insulation performance of the cable could still gradually increase and tanδcould decline after one week of repair for the cross-linked nano material/polyethylene composite insulated cable repair technology.One month after the repair,the overall cable is gradually stabilized,the insulation resistance is also gradually stabilized,the field strength is close to the insulation field strength of nearby cables,the water tree resistance is increased,the dielectric loss and leakage current are significantly reduced,and the withstand voltage level is improved,which is more suitable for the future power grid development.