CAJ | 학술논문

为深入研究气体绝缘开关设备(gas insulated switchgear，GIS)中隔离开关分合空载短母线产生的触头间隙重复击穿现象，实现隔离开关操作全过程特快速暂态过电压(very fast transient overvoltage，VFTO)的准确仿真，建立了252 kV GIS试验平台，对GIS隔离开关分合产生的间隙重复击穿过程及影响因素进行了试验研究。通过同步测量触头间隙电压及长度，获得了隔离开关分合操作中触头间隙击穿电压与间隙长度的统计关系。统计结果表明，操作过程中间隙击穿电压与间隙长度的关系与工频电压下各长度的击穿电压基本吻合，且具有极性效应。每次间隙放电产生的空间电荷促进了后续击穿的发生，且首次放电越剧烈，这种趋势越明显。负载侧残余电压衰减时间常数约为160 min，仿真时可不计重复击穿间歇残余电压的衰减。相同的触头间隙恢复电压下，接地腔体对间隙电场分布影响不大。基于上述研究结果建立了隔离开关操作全过程 VFTO 仿真模型，仿真结果与实测结果基本吻合。
위심입연구기체절연개관설비(gas insulated switchgear，GIS)중격리개관분합공재단모선산생적촉두간극중복격천현상，실현격리개관조작전과정특쾌속잠태과전압(very fast transient overvoltage，VFTO)적준학방진，건립료252 kV GIS시험평태，대GIS격리개관분합산생적간극중복격천과정급영향인소진행료시험연구。통과동보측량촉두간극전압급장도，획득료격리개관분합조작중촉두간극격천전압여간극장도적통계관계。통계결과표명，조작과정중간극격천전압여간극장도적관계여공빈전압하각장도적격천전압기본문합，차구유겁성효응。매차간극방전산생적공간전하촉진료후속격천적발생，차수차방전월극렬，저충추세월명현。부재측잔여전압쇠감시간상수약위160 min，방진시가불계중복격천간헐잔여전압적쇠감。상동적촉두간극회복전압하，접지강체대간극전장분포영향불대。기우상술연구결과건립료격리개관조작전과정 VFTO 방진모형，방진결과여실측결과기본문합。
To research the phenomena of repeated breakdown of contact gap of the disconnector in 252 kV gas insulted switchgear (GIS) thoroughly when the disconnector is used to switch on/off no-load short bus and to implement accurate simulation of very fast transient overvoltage (VFTO) during the whole switching process of the disconnector, a test platform for 252 kV GIS is constructed to perform experimental research on repeated breakdown process of the disconnector contact gap and its influencing factors. Through synchronously measuring the gap voltage and the length of contact clearance, the statistic relationship between the breakdown voltage of contact gap and the length of contact clearance during the switching on/off of the disconnector is obtained. Statistical results show that the relationship between contact gap breakdown voltages and the lengths of contact clearance during the switching on/off process basically agrees with the breakdown voltages of corresponding lengths under power frequency voltage, and there exists the polarity effect. The space charge produced by every time of gap discharge promotes the occurrence of follow-up breakdown, and the more violent the first time of discharge is, the more obvious this trend will be. The attenuation time constant of residual voltage at load side is about 160 min, so the attenuation of residual voltage in the intermittence between the repeated breakdowns can not be taken into account in the simulation. Under the same restoring voltage of the contact gap the residual voltage at the load side does not obviously influence the electric field distribution in the gap. Based on above-mentioned research results, a VFTO simulation model of the whole switching on/off process of the disconnector is built, and the simulation results basically coincide with the measured results.