Calculation and Analysis of VFTO under Different Reignition Arc Models of Isolating

The accuracy of the arc description of the isolation switch is a key factor affecting the calculation accuracy of the fast transient overvoltage (VFTO). In the current simulation calculation, the commonly used resistance model is equivalent to isolating the switching arc, so that it is impossible to deeply simulate the changes of various state quantities during the arc development process. Therefore, based on the theory of multiple reignition arcs and the theory of segmented arcs, this paper compares and analyzes three equivalent models of isolating switch arcs, and calculates and analyzes the internal VFTO of a gas insulated substation (GIS) in a 550kV power station. It is proved that the model can simulate the physical process of the arc during the operation of the isolating switch more accurately, and it is practical for the numerical calculation and characteristic analysis of VFTO.