高压直流GIL中盆式绝缘子表面电荷积聚与消散的实验研究  

Experiment Study of Surface Charge Accumulation and Decay on a Cone-type Insulator in HVDC GIL

作　　者：张贵新[1,2] 张博雅[1,2] 王强[1,2] 李金忠[3] 

机构地区：[1]清华大学电机工程与应用电子技术系,北京100084 [2]清华大学电力系统及大型发电设备安全控制和仿真国家重点实验室,北京100084 [3]中国电力科学研究院,北京100192

出　　处：《高电压技术》2015年第5期1430-1436,共7页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2014CB239502)~~

摘　　要：研究直流电压下绝缘子表面电荷积聚及其抑制措施,是开发直流气体绝缘管道输电线路(GIL)的一项关键技术。因此建立了一套盆式绝缘子表面电荷测量系统,采用静电探头法,在空气中对施加了直流电压后的环氧树脂盆式绝缘子进行了表面电位的测量,研究了不同极性、不同幅值电压以及极性反转情况下表面电荷的积聚现象,并对表面电荷的消散进行了测量。实验结果表明:绝缘子表面电荷分布与所施电压极性密切相关;在0.5 MPa空气中,随着施加电压幅值(+40^+70 kV)增加,绝缘子表面电荷急剧增加(负电位最大处从-200 V增加到-3 000 V);在0.5 MPa空气中,先后施加+70 kV及-40 kV电压,绝缘子局部表面电荷激增现象明显(正电位最大处由500 V增大到超过2 500 V);在0.1 MPa空气中施加+40 kV电压,在0~300 min内,绝缘子表面电荷消散近似指数衰减过程,时间常数约为104 s数量级。Study of insulator surface charge accumulation and its suppression is one of the key techniques in developing HVDC gas-insulated transmission line （GIL）. Consequently, we established a surface charge measurement system for the cone-type insulator in a GIL unit. Based on the electrostatic probe method, the surface potentials on a cone-type insulator made of epoxy resin under DC voltage were measured. The surface charge accumulation phenomenon under different voltage polarities, voltage amplitudes, as well as polarity reversal process were studied. And the surface charge decay process was also measured. The experimental results show that surface charge distribution of insulators is closely related to the polarity of the applied voltage. In 0.5 MPa air, with the increase of the voltage amplitude （＋40～＋70 kV）, the surface charge increases significantly （the maximum negative potential increases from -200 V to -3 000 V）. Moreover, in 0.5 MPa air, under polarity reversal condition （first ＋70 kV and then -40 kV）, surface charge of some certain area can in- creases sharply （the maximum positive potential increases from 500 V to over 2 500 V）. In 0.1 MPa air, after ＋40 kV voltage being applied, the decay process of the surface charge within 300 minutes is similar to exponential process and the time constant of the decay rate is about 104 s order of magnitude.

关 键 词：高压直流 GIL 表面电荷 盆式绝缘子 积聚 消散 静电探头 

分 类 号：TM216[一般工业技术—材料科学与工程]