Log Periodic Antenna Based Partial Discharge Detector for Condition Monitoring of High Voltage Insulators

This paper discusses the use of electromagnetic method of partial discharge detection for detecting and localizing partial discharges in high voltage insulators. In a power system, the condition of power line insulation used in transmission and distribution networks play a vital role in providing an uninterrupted power supply. Partial discharges that form in the insulators may be one of the main reasons for the failure of power line insulators. Therefore, pre-identifying partial discharges in high voltage insulators is essential in maintaining a reliable power system. In this study, a log periodic antenna is designed in order to detect the electromagnetic signals emitted from partial discharges, which are in a wide frequency band. Although the acoustic method can be used to localize the source of partial discharges, background noise can interfere with the process. Thus, in order to detect the electromagnetic signals in the wide frequency band, a log periodic antenna in the range 0.9 – 2 GHz has been designed. To localize and measure the severity of the source of partial discharges on the insulators, the designed antenna is mounted on an unmanned aerial vehicle.