应用SF_6气体分解产物的高压开关设备故障诊断

Fault Diagnosis of High Voltage Switchgears by Decomposition Products of SF_6

全封闭式组合电器(gas insulated switchgear,GIS)、SF6断路器等高压开关设备广泛应用于110 kV及以上电压等级的电网中,设备故障诊断及状态判断是亟待解决的关键问题。分析SF6开关设备发生放电、过热等故障产生的气体分解产物,提出不同故障类型的分解产物特征气体,比较设备故障诊断现有判据,提出开关设备故障现场预判的参考指标及综合诊断依据。给出基于SF6气体分解产物的开关设备故障诊断应用案例,分析悬浮电位放电、零件连接异常和导体异常发热故障等设备潜伏性缺陷诊断和GIS设备故障间隔定位,结果表明SF6气体分解产物的开关设备故障诊断技术具有可行性和广阔的应用前景。

High voltage switchgears such as gas insulted switchgear （GIS） and circuit breaker （CB） are widely applied to power networks in voltage grades of 110 kV and above, thus the fault diagnosis of HV switchgears and the state judgment of their states are key problems to be solved urgently. By means of analyzing gas decomposition products produced by such faults as overheat and discharging occurred in SF6-filled HV switchgears, it is proposed to distinguish different fault types by characteristic gases in decomposition product; comparing with existing criteria for equipment fault diagnosis, the reference indices for on-site prejudgment of HV switchgear faults and the foundation for synthetical diagnosis are proposed. Application cases of HV switchgear fault diagnosis based on decomposition products of SF6 gas are given, the diagnosis of latent defect in HV switchgear such as discharge caused by floating potential, abnormal joint of parts and abnormal heating of conductors as well as the fault location in GIS are analyzed. Research results show that the diagnosis of HV switchgear faults based on decomposition products of SF6 gas is feasible and possesses expectable application prospect.