Simulation Analysis of Miniaturized Butterfly Antenna for GIS Partial Discharge Detection

The electric field distortion caused by GIS defects can cause partial discharge or equipment insulation performance degradation. UHF method is widely used to detect partial discharge. The performance of UHF antenna directly affects the partial discharge detection effect. Miniaturization of antenna size is one of the main objectives of antenna structure optimization. This paper establishes a circular butterfly antenna simulation model, elliptical groove is dug on the radiation patch, and the parameters are simulated and optimized by Ansoft HFSS software. The simulation results show that after changing the antenna structure, the resonant frequency increases, the S11 corresponding to the resonant frequency increases, and the gain decreases. After the structure optimization, the E-plane curve is more obvious than the E-plane curve corresponding to the circular butterfly antenna, the surface curve is W-shaped. After the structure optimization, the impedance matching at the resonant frequency is better than that before the structural change, the resonant frequency shifts from 2.5 GHz to 2.7 GHz, and the S11 corresponding to the resonant frequency changes from -25.57 dB to -45.9 dB, meets the design requirement of S11 less than -10dB. The bandwidth of the antenna is increased from 0.45 to 0.5GHz, and the final antenna has a structural size of 52 mm *50 mm*1.2 mm.