Wideband Circuit Modeling of a Adjustable VFTO Simulator Considering Frequency-Dependent Characteristics

Very fast transient overvoltage (VFTO) induced by switching operation in gas insulated switchgears (GIS) might cause disturbances and damages to terminated devices and equipment of both the primary and secondary sides. This paper introduces a VFTO simulator design for experimental researches and tests in laboratory. The wideband circuit model has been built considering both the pulse generator and equivalent transmission line model in frequency domain. The simulation result shows good agreement with the time-domain Spice model, and the adjustment of frequency-dependent characteristics by circuit parameters is also discussed.