Trapezoidal toothed log-periodic UHF antenna for partial discharge detection.

This paper presents a trapezoidal toothed log-periodic ultra-high frequency antenna for partial discharge (PD) detection in high-voltage power equipment. The proposed antenna features a novel trapezoidal toothed structure and a systematic parametric optimization process, achieving an impedance bandwidth of 0.5-3 GHz (VSWR < 5) and a maximum gain of 6.34 dBi at 1.75 GHz. Experimental validation in a controlled sulfur hexafluoride (SF6) gas environment demonstrates the antenna's ability to detect weak PD signals with a high signal-to-noise ratio of up to 20 dB and generate clear phase-resolved partial discharge (PRPD) patterns. The obtained PRPD patterns aligning well with theoretical expectations and commercial detection systems, highlighting the antenna's potential for real-time PD monitoring and fault diagnosis in high-voltage power systems.