When a single phase grounding fault happened in neutral ineffectively grounding system, arc fault usually generated. Most of the existing arc models for the electric network are realized via the switch, which has a certain gap with the actual arc grounding. Firstly, this paper combines Cassie arc model with Mayer arc model to make it more in line with the actual arc grounding, and applies it to 10 kV simulation power grid. Then, a large number of simulations on the electric arc occurring in different closing phase angles and different feeders are done with EMTP in neutral point ungrounded power grid, power grid of the neutral point connected with arc suppression coil and neutral point via high resistance grounding network. Finally, the method of wavelet correlation analysis is used to select the fault line in Matlab. The results show that the method proposed can apply to most arc grounding faults, but it has some limitations for the arc fault in the vicinity of zero points of voltage.