A Review of the History of the Development of Partial Discharge Testing

PD testing is routinely used on all types of medium and high voltage equipment both as a factory quality assurance test for the electrical insulation, and as a tool to detect when the electrical insulation in operating HV equipment is deteriorating and may fail. Today there are dozens of vendors of PD instruments, but the first PD tests were made by researchers over a century ago, to understand the corona and PD phenomena. This paper will trace some of the key research and developments that led to the current state of the technology. The authors encourage readers to correct misinformation or any key development that is missing.