Study On AC Flashover Performance Of Artificially Polluted XP-160 Insulators At Various ρ_ESDD And ρ_NSDD

Contamination flashover of insulator strings is one of the most serious natural disasters, and it is also one of the most important pacing factors for determining insulation coordination of power system. The flashover performance of contaminated insulators and the relationship between AC flashover voltages of contaminated insulators and pollution severity must be further researched. A large number of researches about the influence of the equivalent salt deposit density (ρESDD) on AC flashover voltage (Uf) of polluted insulators have been done home and abroad, but the research on the influence of the non-soluble deposit density (ρNSDD) on Uf is few. And the relationship among Uf,ρESDD andρNSDD has never been found. In this paper, a lot of laboratory experiments were carried out on artificially polluted XP-160 insulator strings in the artificial fog chamber. Based on test results, this paper obtained following calculations:(1) Various density soiling solution was layout to do researches on the effects of bothρESDD andρNSDD on the AC flashover voltage of the artificially polluted XP-160 insulators. The results show that both theρESDD andρNSDD have influence on the Uf of the artificially polluted insulators, and the relationship between Uf andρESDD is the same as that between Uf andρNSDD in which the Uf reduces with the increase ofρESDD by a power function. BothρESDD andρNSDD are mutually independent as for the influence on Uf.(2) Test results show that the components of nonsoluble contaminations have influence on the AC flashover voltage of polluted XP-160 insulators. The flashover voltages of XP-160 insulators contaminated by kaolin are lower than that of kieselguhr.(3) The relationship among the flashover voltage of an artificially polluted XP-160 insulator string of 7 units,ρESDD andρNSDD is deduced by least-squares procedure and Tab Curve program. It indicates that the relationship among them could be expressed as dU f = KρE?ScDDρN?SDD, and K, c and d are 34.2, 0.24, and 0.14 respectively. The test of significance and verification were done to insure the equation ( U f = KρE?ScDDρN?dSDD) agrees well with the test result, and it indicates that the calculating results are quit approximate with test result.(4) Since that bothρESDD andρNSDD have influence on Uf of contaminated insulators,ρESDD andρNSDD must be both considered in artificial contamination test. Attentions...