Design of an Ultra-Wide Band Microstrip Patch Antenna for Partial Discharge Detection on Power Transformer

The reliability of the power system depends on the quality of the electrical insulation system of high voltage power equipment. Partial discharge (PD) activity in the power apparatus is an indication of insulation degradation due to the presence of defects in the insulation. The occurrence of a partial discharge activity in the insulation may lead to a catastrophic breakdown of the power equipment and may cause a power outage and penalty costs to the power utilities. A Partial discharge monitoring system on a power transformer is an effective and accurate technique for inspecting the insulation condition and identifying potential faults in power transformers. UHF sensors such as UHF Antennas play a vital role in the UHF PD monitoring system. However, UHF sensors still have sensitivity and accuracy issues in detecting partial discharge, especially in online PD monitoring, where there is a high level of electromagnetic interference. To address noise disturbance issues that affect the UHF antenna's sensitivity, we have designed an ultra-wideband (UWB) circular microstrip patch antenna operating in the UHF range. The designed antenna was simulated and optimized using HFSS software. The antenna was designed on FR4-epoxy substrate whose thickness is 1.6mm and dielectric permittivity of 4.4. The radiating patch and ground plane of the antenna are made of a perfect electric conductor (PEC). The designed microstrip patch antenna has a working frequency from 1.18GHz to 3GHz with three frequency bands at three resonance frequencies of 1.3GHz, 2.2GHz, and 2.83GHz respectively. The multiband behaviors will allow this antenna to suppress noise such as noise due to corona and electromagnetic interferences from telecommunication such as GSM.