Research On Rapid Identification Of Arc Grounding Overvoltage In Distribution Network

Power system overvoltage is an important factor affecting the safe operation of power grids and electrical equipment.Arc grounding overvoltage is one of the most common internal overvoltages in distribution networks.It has a long duration and poses a huge threat to the safe and stable operation of power systems.At present,there are few researches on arc ground fault simulation models.This paper compares the advantages and disadvantages of current common arc models.From the perspective of electric breakdown and thermal ionization of arc current zero period,the arc extinguishing and reignition process are studied.An improved KEMA model was established to describe the nature of the arc when a fault occurred.The arc model was built in RTDS and compared experiments were carried out to prove its correctness and effectiveness.And the simulation model of a lOkV distribution network in Nanning,Guangxi,is built to simulate the arc ground fault in the distribution network.Through the analysis of the simulation results,it is proved that the improved KEMA model can accurately describe the arc extinction when the fault occurs in the distribution network.Re-ignition process.Then the simulation waveforms such as the current and voltage resistance of the fault phase are analyzed,which lays a foundation for rapid identification research.The advantages and disadvantages of the existing various filtering methods are analyzed.The mathematical morphology method based on multi-scale and multi-structural element edge detection operator is used to solve the problem of rapid identification of arc grounding overvoltage in distribution network.A large number of actual faults and simulation faults of a lOkV distribution network in Nanning,Guangxi,were identified,and then the parameters such as fault closing angle and transition resistance in the line were simulated separately,and compared with the traditional identification method,the method was proved to be distributed.The arc grounding overvoltage in the network has a very high recognition accuracy and applicability.