That traditional arc models can’t fit the ampere characteristic of the whole arc burning period must be solvedin order to research the transient process and its factors during live breaking cables. Based on the improved arc black-box model

establish a stimulated circuit during live breaking 10kV non-loaded cable in ATP-EMTP. Then researchthe effects that the original phase angle

cable length

cable section area caused to the arc burning transient process

also find the relation between the arc current and the capacitive current. The results show that

longer and wider thecable is

larger arc current and longer burning time there will be

however

effects of the original phase is negligible;the arc current will get larger when the capacitive current gets larger

and the arc current will change more obviouslywhen the capacitive current is larger than 0.2 A. Finally

according to the result of the test of the electric arc

anamendment suggestion on the existing arc suppression strategy is proposed with considering a margin of safety.Whether or not use arc-extinguishing switch

the threshold value of capacitance current 0.5 A is amended to 0.45 A.