摘  要:　复合绝缘子因其重量轻、机械强度高、耐污闪性能好、运行维护方便等优点在电力系统中得到了广泛应用。但复合绝缘子仍不断发生污闪，这与现有的人工污秽试验仅考虑盐密的影响不无关系。因此，本文选择110kV复合绝缘子为试品，研究了盐密(ESDD)和灰密(NSDD)对其污闪特性的影响，并分析了复合绝缘子的闪络过程和闪络机理。

　　　本文研究表明：人工污秽试验中，复合绝缘子污闪电压Uf与ESDD和NSDD均相关，但二者的影响是彼此独立的。随着ESDD或NSDD的增加，其Uf均按幂函数规律降低，ESDD和NSDD对Uf影响的特征指数分别为0.135、0.139，即对于复合绝缘子，灰密的影响大于盐密，这与瓷绝缘子相反。通过对大量试验数据及试验结果的分析，本文得到110kV复合绝缘子污闪电压可表示为：。

关键词：复合绝缘子；盐密；灰密；闪络；憎水性

ABSTRACT:Composite insulator has advantages of less weight, higher mechanical strength, more excellent anti-contaminated characteristic, easier to maintain. Therefore, the composite insulator is widely used by power utilities in many countries. However, as more and more composite insulators are put into service, there are some problems emerging, the unavoidable reason of flashover on composite insulators when contaminated on surface, I think, it may be related with the pollution test method in which the Non-soluble Deposit Density (NSDD) does not be included. Aimed at the problems of composites in operation, in the paper the AC flashover characteristic of polluted composite insulators under the conditions with different ESDD and NSDD is researched by test. Moreover, the AC flashover mechanism and flashover process of composite insulators under the different polluted level is analyzed.

　　　According to the test results carried in the artificial fog chamber, this paper analyzes the effects of the equivalent salt deposit density (ESDD) and the non-soluble deposit density (NSDD) on the flashover performance of the 110kV composite insulator. The result shows that the flashover voltage Uf of the 110kV composite insulators decreases with the increase of both ESDD and NSDD by an power function with a negative index that is 0.135 for ESDD and 0.139 for NSDD, which is opposite with a porcelain insulator. By analyze of test data and experimental results, the formula of flashover voltage of 110kV composite insulator can be expressed as: .

Keywords: composite insulator；Equivalent Salt Deposit Density (ESDD)；Non-soluble Deposit Density (NSDD)；flashover；hydrophobicity