Simulation of VFTO by ATP/EMTP with Various Arc Models
Several arc models representing a disconnector’s closing operation in a 252kV gas insulated switchgear (GIS) are implemented with a computer program ATP/EMTP to simulate very fast transient overvoltage (VFTO). Arc models are used as black box models in connection with a test circuit. Theoretical bases, formulas and realizations of these models are described. Arc models’ parameters are mainly pinpointed by fitting their simulation results with VFTO waveforms measured in a real 252kV GIS test setup. Comparisons between arc models’ simulation results and measurement indicate that dynamic arc models based on Cassie and Mayr theories give more realistic results with particular regard to VFTO’s peak value and frequency spectrum.