Analysis of Arc Model and its Application in Single-phase Grounding Fault Simulation in Distribution Networks

The single-phase arc grounding fault is the main fault form in medium voltage distribution networks. In this paper., the Mayr model is used to study the characteristic of single-phase grounding fault current by adjusting the time constant τ and the dissipated power P, which belongs to the parameters of the Mayr model. The equivalent sequence network diagram of the phase A-to-ground fault in the feeder of the resonant ground distribution system is used to construct the simplified circuit. And then the variation law of arc voltage and current waveform under the change of time constant τ and dissipated power P is analyzed. The results show that increasing τ within a certain range or reducing P can change the arc from the arc extinguishing state to the continuous arcing state. Comparing with the true measuring voltage and current., simulation results show that the simplified zero-mode circuit with Mayr arc model for distribution networks can effectively obtain proper and valid voltage and current waveforms.