An Uniform Wideband High Frequency Current Transformer Sensor for Partial Discharge Measurement in High Voltage Apparatus

In this paper, a novel inductive sensor solution for partial discharge (PD) measurement in high voltage equipment is proposed. The developed sensor is a low-cost high frequency current transformer (HFCT) which has been developed in the laboratory for measurement of PD events in high voltage power apparatus. The sensor has been fabricated to detect corona and surface discharge events in the laboratory. The frequency response of the proposed sensor has been initially examined using simulation and were further verified using experiment. Using the proposed sensor, PD measurement has been conducted on two standard sources i.e. corona and surface discharge, respectively. Investigations revealed that the proposed sensor can detect PD events accurately operating within the frequency band of 250 kHz to 10 MHz, ideally suited for PD measurement in any high voltage (HV) apparatus. The performance of the developed sensor is found to be better than the commercially available HFCT in terms of PD detection sensitivity. Thus, the proposed sensor can be used for PD monitoring in high voltage power apparatus.