A Coplanar Waveguide Based Antenna for Partial Discharge Detection in Gas-insulated Switchgear

Partial discharge (PD) monitoring in gas-insulated switchgear (GIS) has been predominantly monitored using ultrahigh frequency sensors. This is attributed to the superior performance of such sensors in detecting and localizing partial discharge current pulses inside gas-insulated switchgear. In this paper, a coplanar waveguide antenna, widely used for wireless communication applications, has been optimized to operate over the UHF frequency range (0.3GHz - 3GHz). The final proposed antenna size is 120mm x 120 mm, which can fit internally within high voltage GIS structures. The reflection coefficient of the optimized sensor shows that it covers most of the UHF range (0.7GHz – 3GHz). The antenna radiation pattern is also presented, and the obtained results are discussed. Finally, a 3D Finite Element (FE) model for a small section of a GIS has been implemented to examine the antenna performance in detecting PD pulses within GIS structures.