Electromagnetic-circuit co-simulation of very fast transient overvoltage in gas-insulated switches

The very fast transient overvoltage (VFTO) originating from operations of an isolating switch in a gas-insulated switch (GIS) will cause dangerous interference to the switch and its peripherals. Aiming at the engineering issue, a collaborative simulation method by field-circuit-wave of VFTO radiation interference is proposed in this paper. With a combination of project cases, the GIS equivalent circuit is first extracted by means of quasistatic electromagnetic (EM) field analysis. Furthermore, the equivalent time-varying voltage source of VFTO is obtained by associating the time-varying resistance model of the switching arc and the broadband circuit method. Finally, using the transient full-wave technique in the time domain, the spatial EM interference by VFTO is simulated. It turns out that this method has high significance to the high-voltage switch design.