Miniaturized Broadband Antenna Loaded With Frequency Selective Surface for Corona Discharge Detection

Corona discharge is a common phenomenon on high-voltage transmission lines that can lead to insulation damage and power loss. Antenna detection is one of the current standard detection methods, but it suffers from limited sensitivity. To address this issue, this article proposes a frequency selective surface (FSS) array operating in the corona discharge frequency band. The FSS array has <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$15\times 15$ </tex-math></inline-formula> identical cells. Each cell consists of two metal patches. The upper patch is constructed of a twisted cross-shaped cell, while the bottom patch is constructed of a cross cell with patch inductive components. The cell’s dimensions are <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10\times 10\times 1.6$ </tex-math></inline-formula> mm, with S<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${}_{11} \lt -10$ </tex-math></inline-formula> dB in the corona discharge frequency band. We superimpose the array onto the antenna and use ANSYS HFSS module to simulate how the distance between the antenna and the array affects antenna performance. The results suggest that the optimum antenna performance occurs when the distance is 20 mm. Corona discharge experiments revealed that the amplitude of signals detected by FSS loaded on the detection antenna is 128%, 130%, 132%, and 135% higher than the original antenna at detection ranges of 1, 4, 7, and 10 m, respectively. Moreover, the antenna achieves the farthest detection distance of 13 m.