摘要
通过对复合绝缘子用芯棒在型式试验中发现绝缘强度降低的现象进行分析,认为芯棒存放或者加工过程中发生了吸湿现象。为了研究芯棒吸湿引起的绝缘强度下降情况、吸湿特点以及预防措施,对芯棒进行了吸湿率、直流击穿、受潮后放电紫外线测量等试验。试验结果显示,吸湿会加剧芯棒局部放电,整支芯棒由于场强畸变（110kV复合绝缘子吸湿后畸变率为52.8%-90.4%）也会加剧局部放电现象,间隔性的吸湿引起场强畸变（〉95%）高于完整相同长度受潮的情况。芯棒吸湿集中在玻璃纤维裸露处,属于Fick扩散。热烘（〉50℃）会导致芯棒热失重,当重新浸入潮湿环境中会加剧吸湿,但提高环境温度（≥30℃）可有效抑制芯棒吸湿。对吸水率的深入分析认为,吸水率〈0.03%可满足同标准规定的直流击穿强度,并提出等效渗入深度概念。综合上述研究结果得出,加强原料和工艺控制,提高芯棒的生产和储存环境温度,生产过程中增加吸水率检测,运输过程中切面封RTV涂料等手段可有效降低芯棒的吸湿情况。
The insulation performance of fiber reinforced plastic（FRP） rods may decrease because of their moisture absorption in the procedure of manufacture and deposit. Therefore, the moisture absorption, power frequency puncture voltage, and the ultraviolent ray of FRP rods were tested after moisture absorption and so on. The results show that moisture absorption of FRP rods, as well as field distortion（the percent of field distortion on the 110 k V composite insulators is up to 52.8%-90.4%）, can make the partial discharge of FRP rod more serious. The field intensity of composite insulators with part interval moisture absorption（more than 95%） is higher than that with part whole moisture absorption. The moisture absorption happens on the naked glass fiber of FRP rod and follows the Fick law（the moisture absorption of samples can attain saturation in short time）. The thermal dying process may cause the weight loss which can make the moisture absorption of FRP rod more serious when FRP rod is taken in the wet environments, but the moisture absorption will be effectively inhibited if the temperature of environments rises（≥30 ℃）. The moisture absorption rate should be kept lower than 0.03%, and a new conception of the equivalent depth of permeating is introduced. It is suggested that strengthening the quality detection of raw material, increasing the environment temperature of FRP rod produce and storage, doing the moisture absorption test in the productive process, covering the section by RTV, and etc, can effectively decrease the moisture absorption.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2014年第11期3468-3476,共9页
High Voltage Engineering
基金
国家电网公司科技项目(SG[2009]58)
国家重点基础研究发展计划(973计划)(2009CB724504)~~
关键词
棒形复合绝缘子芯棒
吸湿性
绝缘性能
热失重
Fick定律
等效渗入深度
fiber reinforced plastic rod（FRP rod）
moisture absorption
insulation capability
thermal weight loss
Fick law
equivalent depth of permeating
