人工污秽下盐/灰密对普通悬式绝缘子串交流闪络特性的影响

污闪是电力系统的严重自然灾害之一,国内外对盐密(ESDD)的影响进行了大量的研究,但对灰密(NSDD)影响的研究较少。文中以7片串普通悬式绝缘子XP-160为试品,在人工雾室中进行了大量的人工污秽试验,分析了ESDD和NSDD的变化对人工污秽绝缘子交流闪络电压的影响。试验结果表明:在人工污秽试验中,ESDD和NSDD均对绝缘子交流闪络电压有影响,与ESDD对人工污秽绝缘子串绝缘子交流闪络电压的影响一致,人工污秽绝缘子串交流闪络电压与NSDD也呈幂函数关系。在对交流闪络电压的影响上,ESDD和NSDD是相互独立的。因此,污区的划分不仅应考虑ESDD,同时也应考虑NSDD。对于7片串XP-160,文中还给出人工污秽试验条件下绝缘子串的交流污闪电压表达式。

Influence of ESDD and NSDD on AC Flashover Characteristic of Artificially Polluted XP-160 Insulators

Pollution flashover of insulator strings is one of the most serious natural disasters.A large number of studies about the influence of the equivalent salt deposit density(ESDD)on AC flashover voltage of polluted insulators have been done home and abroad,but few study done about the influence of the non-soluble deposit density(NSDD)on it is done.A lot of laboratory experiments are carried out on polluted XP-160 insulator string of 7 units in the artificial fog cabinet.Based on the tests results,the effects of both ESDD and NSDD on the AC flashover voltage of the artificial polluted XP-160 insulators are also analyzed.It shows that both ESDD and NSDD have influence on the AC flashover voltage(Uf)of the artificially polluted insulators,that the relationship between Uf and ESDD is the same as the one between Uf and NSDD in which the Uf reduces with the increase of ESDD by a power function,and that both ESDD and NSDD are mutually independent as for the influence on Uf.Therefore,while mapping a pollution level for a district,both ESDD and NSDD,should be considered.Then,it shows the relationship between the flashover voltage of an artificial contaminated XP-160 insulator string of 7 units and ESDD as well as NSDD.