雾霾对绝缘子交流闪络特性的影响

Effect of Fog-haze on AC Flashover Performance of Insulator

为研究雾霾环境对绝缘子闪络特性的影响,在自制小型雾霾室内利用超声波雾发生器产生水雾并启动气溶胶发生器,将不同成分(硅藻Ca SO4和(NH4)2SO4)的颗粒物通入试验罐内模拟雾霾环境,并对不同成分、粒径的气溶胶雾霾环境下的绝缘子进行多次交流闪络试验,分析了雾霾成分、颗粒粒径、盐密对绝缘子交流闪络电压影响规律。结果表明:雾霾颗粒会导致绝缘子表面快速积污,20 min内绝缘子表面等值盐密最大可增加0.028 mg/cm2,引起闪络电压降低32.2%;盐类气溶胶和小粒径气溶胶对闪络电压影响较大,可使轻度污秽绝缘子闪络电压降低20%以上;雾霾环境中绝缘子交流闪络依然为沿面闪络。

In order to research the influence of fog-haze conditions on the flashover performance of insulators, we utilized an ultrasonic fog generator to produce water sprays pervading the small fog-haze chamber designed by ourselves. Meanwhile, different components of fog-haze including diatomite, calcium sulfate（CaSO4）, and ammonium sulfate（（NH4）2SO4） were turned into tiny particles by the aerosol generator, and then these particles were transported into the fog-haze room in order to simulate the fog-haze environment. After the testing platform had been built, we carried out several experiments of AC flashover of insulators so as to find how the three factors, namely, fog-haze components, particle size, and salt deposit density affected flashover voltage of the insulators by fitting method. The testing results show that the fog-haze particles may lead to the contamination deposited rapidly on insulator surface, the insulator surface equivalent salt density can increase by 0.028 mg/cm2 within 20 min, and the flashover voltage may decrease by 32.2%. Salt aerosol and aerosol with smaller diameter will greatly impact flashover voltage, and it can cause flashover voltage of polluted insulator to reduce by more than 20%. The ac flashover of insulator in fog-haze conditions is still a phenomenon of surface flashover.