GIS不同绝缘缺陷的局放检测有效性对比研究  

Comparative Study on Partial Discharge Test Effectiveness of Different Insulation Defects in GIS

作　　者：刘弘景[1] 李伟[1] 任志刚[1] 高旭泽 任明[2] 孙白 娄奇鹤 LIU Hongjing;LI Wei;REN Zhigang;GAO Xuze;REN Ming;SUN bai;LOU Qihe(State Grid Beijing Electric Power Research Institute,Beijing 100075,China;State Key Laboratoryof Electrical Insulation and Power Equipment,Xi＇an Jiaotong University,Xi＇an 710049,China;Beijing Electric Power Enterprise Association of State Grid,Beijing 100031,China;Urban PowerSupply Company,Beijing Electric Power Corporation,Beijing 100034,China)

机构地区：[1]国家电网北京电力科学研究院,北京100075 [2]西安交通大学电力设备电气绝缘国家重点实验室,陕西西安710049 [3]国网北京市电力公司企协分会,北京100031 [4]国网北京市电力公司城区供电公司,北京100034

出　　处：《绝缘材料》2018年第9期53-60,69,共9页Insulating Materials

摘　　要：针对110 k V真型GIS试品建立了超高频检测(UHF)、超声检测(AE)及高频电流检测(HFCT)的局部放电综合检测系统,并量化对比研究了上述3种局部放电检测方法对不同类型和不同尺度绝缘缺陷检测的有效性。结果表明:当金属尖端长度小于5 mm时,各类测量方法都难以检测到额定电压下的放电脉冲,当金属尖端长度大于5 mm时,HFCT和UHF相对AE较为灵敏,HFCT和UHF能检出的最小缺陷尺度相同;当存在悬浮电极放电时,UHF最为灵敏;对于高压侧绝缘子表面颗粒缺陷,HFCT最为灵敏,当表面颗粒靠近地侧时,AE灵敏度最高;各检测方法均能在运行电压下发现尺度在0.1~2 mm的气隙缺陷。此外,在可检出绝缘缺陷的最小尺度下,HFCT和UHF可分别响应2 p C和10 p C以上的金属尖端、金属颗粒以及绝缘子气隙局部放电,而AE响应相对滞后;各检测方法的信号强度随视在放电量的变化趋势不同,UHF对放电量变化的响应最为敏感。A partial discharge comprehensive detection system of ultra high frequency（UHF）, acoustic emission（AE）, and high frequency current transformer（HFCT） was built for 110 kV real GIS sample,and the effectiveness of above three partial discharge detection methods in the defection of different types and scales of insulation defects were compared. The results show that when the metal tip length is less than 5 mm, all kinds of detection methods are difficult to detect the discharge pulse under rated voltage. When the metal tip length is larger than 5 mm, the HFCT and UHF methods are more sensitive than AE method, and they have the same minimum detectable scales defect. When there is suspended electrode discharge, UHF method is the most sensitive. When there is surface particle defect on the high voltage side of insulator, HFCT method is more sensitive, and when the surface particles are near the ground side, AE method is the most sensitive. All the detection methods can detect the air gas defects with the scales of 0.1-2 mm under operating voltage. Besides, under the minimum detectable scales of insulation defects, HFCT and UHF methods can response to the above 2 pC and 10 p C of metal tip,metal particles, and insulator air gap partial discharges, respectively, and the response of AE method is relatively lagged behind. The variation trends of signal intensity of each method with apparent discharge magnitude are different, and the response of UHF method to the change of discharge magnitude is the most sensitive.

关 键 词：局部放电 气体绝缘组合电器 超高频监测 超声检测 高频电流检测 

分 类 号：TM855[电气工程—高电压与绝缘技术]