低气压下复合绝缘子表面干燥带放电时频特征  

Time-frequency Characteristics of Dry-band Discharges on Polymer Insulator Under Low-pressure Conditions

作　　者：刘勇[1] 杜伯学[1] 王荣亮[2] 张黎明[3] 

机构地区：[1]天津大学电气与自动化工程学院,天津300072 [2]天津市电力公司检修公司,天津300250 [3]天津市电力公司电力科学研究院,天津300041

出　　处：《高电压技术》2014年第8期2348-2352,共5页High Voltage Engineering

基　　金：国家自然科学基金(50777048);哈尔滨理工大学工程电介质及其应用技术省部共建教育部重点实验室开放课题基金(编号略);天津大学自主创新基金(2704)~~

摘　　要：低气压环境下复合绝缘子的干燥带放电特征研究对其在高海拔地区的广泛应用具有重要的理论意义与应用价值。为此，选用取自硅橡胶复合绝缘子的试样，采用减压装置在人工模拟大气环境实验系统下分别模拟100～40kPa等7个不同气压环境，采用NaCI盐溶液分别模拟电导率为2．5mS／cm和5．0mS／cm的污秽等级，研究了不同低气压与污秽等级下复合绝缘子表面干燥带放电的时频特征。结果表明：随着气压的降低，复合绝缘子表面较易形成干燥带，进而引发干燥带放电，但放电发生区域较小，放电强度减弱；在不同低气压环境下，干燥带放电频率主要集中在1kHz以下，但是随着气压的降低，干燥带放电电流中的基波分量增大，谐波分量呈现减小的趋势，干燥带放电的累积电量减小。Understanding the dry-band discharge characteristics of polymer insulator in depression atmosphere is of great importance for polymer insulator＇s application in high-altitude regions. Therefore, with specimens made of silicone rub- ber insulators, we investigated the effect of both low pressure and contamination degree on the time-frequency characteristics of dry-band discharges. Seven atmospheric pressures, from 100 kPa to 40 kPa, were tested in a decompres- sion chamber established in artificial climate-simulating system. In the meantime, different contaminations with conductivity of 2.5 mS/cm and 5.0 mS/cm were simulated using NaC1 solution. Results show that, with the decrease of atmospheric pressure, the formation of dry bands is accelerated and gets easier to induce dry-band discharges on insulator surface, but the discharge area and the discharge strength both have the inclination to decrease. The frequency range of dry-band discharges is mainly below 1 kHz under different low-pressure conditions, however, with decreasing pressure, the fundamental component of dry-band discharge current increases while the harmonic components decrease, and the cumulative charge of dry-band discharges tends to rise.

关 键 词：高海拔 低气压 复合绝缘子 干燥带放电 时频特征 放电量 

分 类 号：TM216[一般工业技术—材料科学与工程]