汕头地区变电站支柱绝缘子自然积污特性研究

Research on Natural Contamination Deposition Characteristic of Post Insulator in Substation in Shantou Area

为研究变电站支柱绝缘子自然积污特性,对广东省汕头供电局辖区内13个变电站进行了4年的自然积污试验,试验所用支柱绝缘子型号为GW4-110,取样时间选择每年10月至次年4月少雨季节,分别测量各个支柱绝缘子的每一个伞裙,然后取整串绝缘子等值盐密(equivalent salt deposit density,ESDD)和灰密(non-soluble deposit density,NSDD)的平均值作为该测量点的污秽,结果表明各测点的测试结果存在差异,同一测量点每年污秽增长不同,ESDD和NSDD相比差距较大。经过分析,得到结论:绝缘子积污与地理位置、积污时间段有关,不同积污时间段、不同测量点所测得的污秽度各有差异;不同积污期间,支柱绝缘子表面ESDD的变化波动小,比较均匀,而NSDD变化分散性大;绝缘子表面NSDD累积速度大于ESDD累积速度;汕头供电辖区变电站污秽等级主要为b级和c级;运行中应关注各测量点的污秽变化情况,随时对个别重污秽区采取应对措施。

In order to studying natural contamination deposition characteristic of post insulator,experiment on natural con-tamination of thirteen substations of Guangdong Shantou power supply bureau was carried out for four years. Type of test post insulator was GW4-1 1 0 and sampling time was rainless season from yearly October to April of the year ensuing. Each umbrella skirt of post insulator was respectively measured and contamination value of the measuring point was average value of equivalent salt deposit density （ESDD）and non-soluble deposit density （NSDD）of the whole string of insulator. Results indicates that there are differences of testing results of measuring points,increase of contamination of the same measuring point is different every year and differences of ESDD and NSDD are larger. By means of analysis,the conclusion indicates that contamination deposition of the insulator is related to geographic location and contamination deposition time,contami-nation degrees of different measuring points in different contamination deposition time are discrepant. In addition,in differ-ent contamination deposition period,changing fluctuation of ESDD on surface of the post insulator is comparatively equal while that of NSDD is relatively disperse and accumulation speed of NSDD on surface of the insulator is bigger than that of ESDD. Contamination grades of substations in power supply areas in Shantou are b and c,meanwhile,it is needed to notice changes of contamination of measuring points in operation and take countermeasures for some serious contaminated areas.