Finite-difference time-domain simulation of partial discharges in a gas insulated switchgear

It is important to estimate the current magnitude and charge amount of a partial discharge (PD) in a gas-insulated switchgear (GIS). In this study, electromagnetic fields generated by a PD in an 84 kV-class three-phase GIS for testing have been measured with a voltage probe installed on the outer surface of an insulation spacer of the GIS tank, and the corresponding simulations have been carried out using the three-dimensional finite-difference time-domain (FDTD) method. FDTD-computed time-domain voltages across spacers agree reasonably well with the corresponding measured ones, and the current magnitude of PD and its charge amount have been estimated