On-line partial discharge measurement within the VHF range for smart energy grid monitoring

Abstract

Insulation quality of switchyard equipment can be determined through the measurement of the strength of partial discharges (PD). PD testing gives an indication of insulation deterioration and incipient faults in a smart grid. A continuous and on air partial discharge monitoring system can be used to determine the presence of high level partial discharge. In this paper a simpler and non-intrusive on air partial discharge monitoring system is described that has been developed and tested in the laboratory. This paper also describes a novel method of developing a PD emulator sub-system with in very high frequency (VHF) range. For detecting the PD signals several considerations for detector circuits have also been discussed. Results of the experiments delineate a feasible method for real-time condition monitoring combined with a proactive, preventative maintenance strategy that can be applied to the future smart grid monitoring system.