摘要
特高压GIS设备进行现场冲击耐压试验时,GIS内部在振荡冲击电压波作用下易发生电磁波折、反射,由此产生的电压波叠加后可能会高于标准要求的试验电压值从而危及GIS设备绝缘。为有效评估振荡冲击电压下GIS设备内部的过电压水平,优化GIS现场冲击电压试验方法。利用EMTP仿真计算软件,基于现场实际试验参数对GIS正常施加冲击耐压以及GIS发生闪络两种工况下的波过程开展了仿真计算分析,得到了GIS设备各节点的电压分布。结果表明,正常情况下对GIS施加振荡型冲击电压时,GIS各节点电压幅值差异较小,一旦发生内部闪络后,在截断电压波作用下,GIS支路末端电压会远超试验电压值进而引发二次闪络。针对该现象,根据仿真计算结果提出在试验回路中加入阻尼电阻的抑制措施,并结合现场实测进行验证。通过对仿真计算及现场实测结果的对比分析,大幅减少了现场冲击耐压试验次数,有效防止现场试验时过电压对GIS设备的损害,为今后开展1 100 k V GIS设备现场冲击电压试验提供了技术依据。
In the process of field impulse voltage withstand test of UHV GIS（gas insulated switchgear）,electromag-netic waves in GIS affected by oscillatory surge voltage are prone to refraction and reflection,and that will causes thevoltage waves superposition may higher than the test voltage required by the standard,endangering GIS insulation.To effectively evaluate the GIS overvoltage in case of oscillatory surge,the impulse voltage test method is optimized.The voltage distribution of each GIS node of is obtained by utilizing EMTP simulation software,based on field test pa-rameters,for the simulation of and analysis on the wave process in two different conditions,normal impulse with-stand voltage of GIS and flashover of GIS in the test process. The results show that GIS nodes demonstrated similarvoltage without noticeable wave process in case of normal oscillatory surge of GIS. However,in case of internal flash-over,the end node voltage of GIS branch affected by the cut-off voltage waves would greatly exceed the test voltage,triggering secondary flashover. In consideration of this case,feasible suppression measures are proposed on the basisof simulation calculation and in combination with actual conditions,which provides a technical basis for the field im-pulse voltage test of 1 100 k V GIS equipment in the future.
出处
《高压电器》
CAS
CSCD
北大核心
2018年第2期20-25,32,共7页
High Voltage Apparatus
