A review of partial discharge detection, diagnosis techniques in high voltage power cables

Partial discharges (PDs) are the first indication of insulation materials degradation. This paper provides a general review on partial discharge in power cables. It starts with discussing the importance of PD detection and its effect on the continuity of operation and reliability of power systems. It then provides a description of the insulation explaining the process that leads to its breakdown. The stresses on the voids inside the power cable are explained and the equivalent circuit is discussed. The paper then discusses the most common methods to detect the partial discharge off-line and on-line, specifically in power cables. Methods of location of partial discharge inside the power cable are discussed as well. The most common signal de-nosing techniques are also briefly explained. Lastly, a deep insight of the current challenges and difficulties in PD detection and monitoring are provided.