Investigation of the Performance of Novel 3-D UHF Antennas for Partial Discharge Detection in Power Transformers

In this article, four proposed ultra-high frequency (UHF) sensors based upon the Vicsek fractal, mandel-box, Island fractal, and Menger sponge geometric shapes are designed, and their performance specifically their suitability for partial discharge (PD) detection inside power transformers is investigated thoroughly using COMSOL Multiphysics software. Most of these designs showed average performance, with the Island and the Menger antennas showing great potential for improvement in terms of gain, and return loss (RL). The Island antenna overall has the best performance for the purpose of PD signal detection inside the oil-immersed transformers. From this study it is concluded that among the evaluated designs, the Island antenna demonstrated the best performance for PD detection, with an ultrawideband response, a gain of 3.8 dBi, ${S}_{{11}}$ of −33.05 dB, and voltage standing wave ratio (VSWR) of 1.38. The Menger antenna also performed well, with a gain of 5 dBi, the S-parameter ${S}_{{11}}$ of −27.08 dB, and wideband characteristics, making it suitable for consideration. The Island antenna performance is investigated experimentally. It can be concluded from the results that there is strong positive correlation between the measured and the simulated values.