支柱瓷绝缘子污层泄漏电流及干带产生的边界条件研究  

Study on the Leakage Current and the Boundary Condition of Dry Band on Pollution Layer of Porcelain Post Insulator

作　　者：袁田[1,2] 向铁元[1] 张锐[2] 周军[1] 刘翔[2] 

机构地区：[1]武汉大学电气工程学院,武汉430074 [2]中国电力科学研究院,武汉430074

出　　处：《高电压技术》2016年第1期214-222,共9页High Voltage Engineering

摘　　要：为了研究瓷支柱绝缘子污层干带产生的边界条件,建立了污层泄漏电流观测平台。通过对24~110 k V瓷支柱绝缘子污秽试验(固体层法)泄漏电流的频谱和雾室的温度、湿度参数测量和分析基础上,深入讨论了污秽试验中污层干带产生的边界条件。试验发现,通过4 000 Hz采样频率和频段的计算方法可减少频谱的偏频和泄漏问题;当初始湿度条件相近时(相对湿度55%~62%),干带产生前一刻的谐波畸变率在0.1733~0.3345,相同灰密下(1.0mg/cm^2),盐密同基波分量成正比;相同盐密下(0.1 mg/cm^2),灰密与雾室内绝对湿度(等同于污层水分交换速率)成正比,并给出了趋势曲线和拟合式。通过对污层频谱测量发现,污层中水分含量与泄漏电流相互制约,在干带产生边界前处于平衡中相互促进状态,谐波畸变率(THD)可灵敏地反映污层的水量。当干带产生和污层水量减少时,谐波畸变率(THD)迅速增高,泄漏电流频谱成波包形连续递减波形。By building a leakage current monitor platform for 24-110 kV porcelain post insulators in artificial pollution tests, we studied the characteristics of the boundary conditions of dry band in pollution layer on the basis of the data of frequency spectrum of leakage current, temperature and humidity of fog room. The offset frequency and spectrum leakage can be dealt with by sampling frequency of 4 000 Hz. The total harmonic distortion （THD） is 0.173 3-0.334 5 before the first dry band appearance if the initial condition is close （the relative humidity is 55%-62%）. Under this condition, the fundamental component is measured when the ESDD are （0.06-0.15） mg/cm2 and NSDD is 1.0 mg/cm2 and the absolute humidity （it is equal to the rate of water exchange between pollution layer and air）is also measured when the ESDD are 0.1 mg/cm2 and NSDD is （0.5-1.5） mg/cm2. The results are proportional to variables of pollution layer and the trend curves are fitted. Water in the pollution layer is related with the leakage current though measuring the frequency spectrum of pollution layer that has been found in the tests. The increase of water in pollution layer and leakage current is mutually reinforced before dry band appearance. The THD is closely related with the water of pollution layer. So the THD will rise and the waveform of frequency spectrum is in wave packet when the dry appearance and water of pollution layer decrease.

关 键 词：污秽 瓷支柱绝缘子:污层干带 频谱 谐波畸变率 凝结水 

分 类 号：TM216[一般工业技术—材料科学与工程]