Design Of Antenna To Detect Partial Discharge In XLPE Cable

XLPE cable has been widely used in China’s power system. When the insulation of thecable insulation is broken, the insulation will release partial discharge phenomenon. Thepartial discharge in cable contains rich UHF signals and the detection and analysis of theseUHF components is helpful to diagnose the condition of cable insulation. This paper aimsto design an antenna with400MHz-1GHz bandwidth to detect UHF signals of partialdischarge in cable.The main research content includes four parts: firstly, designed a balun with gradualtype of structure is designed to match antenna. The impedance conversion betweenantenna and50coaxial cable is realized by the balun and the UHF signal can betransmitted to the acquisition device; second, a Archimedean spiral antenna and aequiangular spiral planar antenna are simulated separately and the performance parametersare compared. Low frequency performance of Equiangular spiral antenna is poor. Thespiral arm of Archimedean spiral antenna is too long. The Archimedean spiral antenna islarger transmission loss and lower efficient; Third, a control variable method is used tooptimize the parameters of these two antenna. Every parameter is optimized step by step;fourth, a complex planar spiral antenna is designed. This antenna integrated theadvantages of Archimedean spiral antenna and equiangular spiral planar antenna. Theantenna performance meet the design requirements. The antenna VSWR is less than2. Thereturn loss is less than-10. The3dB beam width is greater than30degrees.The UHF antennas meet the purpose to detect the partial discharge in XLPE cable.