SF6分解物检测在高压直流套管故障诊断中的应用

摘要

Detection technology of SF6 decomposition products is an important method of electrical power equipment condition assessment and fault diagnosis along with wide usages of gas-insulated devices in power grids.However,most researches have been focused on GISs (Gas Insulated Switchgears),with a rare study on gas insulated wall-bushings and bushings at the valve-sides of converter-transfomers.According to SF6 decomposition mechanism and detection technology and based on data of SF6 decomposition products obtained from bushings in converter stations,regular patterns of SF6 decomposition and its products are analysed.By two field examples,a suggestion is given that abnormal data of SF6 decomposition shuold be systematically analysed by a comprehensive method with laboratory tests,electrical tests,electrical-ultrasonic wave detection and historical analyses.Eventually deficiencies of SF6 decomposition-product detections are discussed.%随着气体绝缘设备在电力系统中的广泛应用,SF6分解物检测成为电力设备状态评估与故障诊断的有效方法.然而目前的研究大都集中于GIS(气体绝缘开关装置),在换流站直流穿墙套管和换流变压器阀侧套管方面少有研究.为此,在介绍SF6气体分解机理和分解物检测技术的基础上,并依据套管分解物检测结果,分析换流站套管SF6分解物的组分含量及其生成规律.通过2个现场检测套管SF6分解物异常实例,说明生产现场开展SF6分解物检测时,应综合实验室检测、电-声-气联合检测及电气试验等手段,并结合历史数据与资料,对异常检测结果进行系统化分析.最后,讨论了SF6分解物检测技术目前存在的主要问题.