Considering Restriking Arc Model 1000kV GIS Very Fast Transient Overvoltage Characteristics and the Influence of Disconnector Speed

In the research of Very Fast Transient Overvoltage(VFTO), the accuracy of arc model of disconnector largely influences the VFTO calculation results. How to accurately simulate the striking and extinguishing process of the arc during the action of the disconnector is the key issue of studying arc model. In this paper, the ATP-EMTP electromagnetic transient program was used to simulate the arc damping by series connection of constant resistance and time-varying inductance, and the built-in MODELS module was used for programming to simulate the restriking process of the arc. The model was applied to a 1000kV GIS test circuit. The voltage and current waveforms were analyzed under the opening and closing operations of the model, and the results were compared with the single breakdown arc model. At the same time, combined with the restriking arc model, the influence of opening speed of disconnector on VFTO was analyzed. The present study suggests that the restriking arc model can better reflect the VFTO characteristics during the breakdown process of disconnector. When the opening speed is less than 0.7m/s, the maximum VFTO of the test circuit increases with the increase of opening speed. When the VFTO amplitude reaches the maximum, it will decrease with the further increase of opening speed.