Load and other effects on measuring partial discharge in power cables

Medium and high voltage power cables are the arteries of the transmission and distribution network. They have been-widely used in the power industry for many years. In insulation condition monitoring of MV and HV cables, partial discharge (PD) measurement is one of the most effective techniques. PD has been recognized as a major cause of insulation failure as almost all insulation breakdown starts from PD phenomenon. To make an accurate insulation assessment, the PD information obtained has to be carefully interpreted with other factors taken into consideration such as load, noise level, fault type, location, etc. This paper investigates the load effect on PD measurement. The PD signal is detected by the inductive sensor and processed with both narrow band and wide band coupling methods. Experimental results are compared with simulation results.