IEC火花试验装置灵敏度分析

Sensitivity analysis of IEC spark test apparatus

火花试验装置的灵敏度会受到环境因素、钨丝电极与镉盘电极等因素的影响。对IEC火花试验装置钨丝电极与镉盘电极在1个检测周期内的交汇/分离轨迹进行了分析,特别区分出钨丝从镉盘通槽"凹入"和"凹出"2种特殊情况;对钨丝电极在镉盘凹槽内的分离角度进行分析,指出分离角度范围为9°~86°,其中接近于垂直分离情况仅占50%;分离角度不同造成分离用时相差6.38倍,进而影响钨丝分离初速度,进而造成火花试验装置每次开路火花灵敏度的明显不同。

The sensitivity of spark test apparatus is affected by environmental factors, tungsten wire electrode and cadmium disk electrode. In this paper, the intersection/separation trajectories of tungsten wire electrode and cadmium disk electrode in a test cycle of IEC spark test device are analyzed. Two special cases of tungsten wire concave in and concave out from cadmium disk slot are distinguished. The separation angle of tungsten wire electrode in the groove of cadmium disk is analyzed. It is pointed out that the separation angle range is from 9° to 86°, and only 50% of them are close to vertical separation. The difference of separation time caused by different separation angles is 6.38 times, which affects the initial separation speed of tungsten wire and leads to the obvious difference of spark sensitivity in each open circuit of spark test apparatus.