交流电场下水滴对导线电晕特性的影响  

The Corona Characteristics of the Conductor Attached with Water Drops under AC Electrical Field

作　　者：胡琴[1] 吴执 舒立春[1] 蒋兴良[1] 杨爽[1] 徐清鹏 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400044 [2]国网重庆南岸供电公司,重庆400060

出　　处：《电工技术学报》2015年第18期237-245,共9页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(51007099);创新研究群体科学基金(51021005)资助项目

摘　　要：导线电晕会带来巨大的危害,是输电线路设计与运行必须考虑的重要因素之一,而降雨天气会严重影响导线的电晕特性。本文在小型电晕笼内对导线表面附着水滴时进行交流电晕试验,同时结合二维和三维有限元仿真来分析导线的电晕特性。研究表明,导线表面布满水的起晕电压远小于导线表面附着少量水滴的起晕电压;根据水滴在电晕过程中的破裂方式提出采用水滴的第一次破裂电压和第一次喷射微滴电压来表征水滴在电场作用下的稳定程度,试验得到导线表面附着三滴水的第一次破裂电压、第一次喷射微滴电压低于导线表面附着一滴水的值;水滴在交流电场中将会做两倍于电场频率的受迫振动,而且水滴在不同的振动位置对空间场强的畸变程度不一,这将导致水滴电晕过程中的瞬时电晕现象;通过三维仿真计算得到导线表面附着三滴水时的空间场强最大值和强场强区域体积大于导线表面附着一滴水的值,说明三滴水时对电场的畸变更为严重。Conductor corona, which would bring huge impacts, is one of the significant factors that should be taken into account during design and operation of transmission line. However, rains are momentous to the corona characteristics of conductors. Combined with 2D and 3D Finite Element Simulations, AC corona test has been carried out with water drops adhered to its surface inside a small corona cage, to figure out the corona characteristics of the conductor. The result shows that： the first and foremost, the corona inception voltage of conductor with water drops is much lower than that of conductor with few drops. Besides, according to the burst types of the water droplets, the first breakup voltage and the minimum micro-drops jetting voltage are used to represent the stability degree of the drops in the electric field. The first breakup voltage and the minimum micro-drops jetting voltage, which were measured under the circumstance of conductor with three water droplets attached to its surface, are lower than those of one-drop-condition. Next, water droplets are forced to vibrate by twice the frequency of electric field under the AC electric field. And different vibration position of the water droplet means different distortion of the electric field. In this case, intermittent-period of corona occurs. Last but not the least, the result of 3D finite element simulation shows that the maximum space field distribution and the volume of high field intensity region of three-drops-conduct are greater than that in one-drop-condition. Therefore, it is indicated that the three-drop-condition has a more severe impact on electric field distortion.

关 键 词：交流电场 电晕 水滴 破裂 振动 空间场强 

分 类 号：TM852[电气工程—高电压与绝缘技术]