交流特高压输电线路绝缘子串污秽耐压特性试验

为研究1000kV特高压输电线路绝缘子串的污耐压特性,按照真型布置,依据GB/T4585-2004采用升降法求取了其50%污秽闪络电压。研究内容包括绝缘子串长与50%人工污秽耐受电压U50%的关系,不同串型下的污耐压特性,附灰密度(NSDD)、上下表面不均匀积污对污耐压的影响等。试验表明,绝缘子串长与U50%呈非线性趋势,按照线性拟合求取的U50%较试验所得出的结果高1.6～10.2%;NSDD的增加使绝缘子的U50%下降;上下表面不均匀积污比均匀积污时的U50%高等。研究结果可供1000kV交流特高压工程绝缘子串的选型及污秽外绝缘配置参数。

Flashover Voltage Characteristic of 1000kV AC Transmission Line Insulator Strings Under Polluted Conditions

This paper researched the artificial pollution withstand voltage character of 1000kV AC overhead line insulator strings in real layout.Using up and down lest methods,the 50% flashover voltage of insulator strings under polluted condition have been obtained according to GB/T 4585-2004.The relation between 50% artificial pollution power withstand voltage U50% with the length of insulator string,the character of artificial pollution withstand voltage in different string types,the impact of NSDD and non-uniform pollution of up and down surface to artificial pollution withstand voltage have been researched.The paper get that the relation of U50% and the length of insulator strings is nonlinear,U50% of linear fitting is 1.6% to 20% higher than that of test;if pollution external design is proceeded according to linear relation,the pieces of insulator strings will be 1.6% to 10.2% less than that by test.U50% of insulator will be decreased with the increment of NSDD,U50% of insulator is higher in non-uniform pollution condition than uniform pollution condition.The achievement of this paper are very important to choose and design insulator strings of 1000kV AC transmission line.