Investigation of partial discharge pulses propagation in single-core and three-phase XLPE cables

Partial discharge in XLPE cables can be employed to detect occurrence of any discharge in them. if any water treeing or insulation deterioration takes place in this type of cables, it would fail very fast and thus on time detection of the causes of failures such as partial discharge signal is very important to improve the reliability of power system network and to extend the life time of the cable. The presence of semi-conducting layers results in a high attenuation of high frequency signals amplitude during their propagation through the cable, and it will be difficult to detect and estimate the actual level of partial discharge in its location. To evaluate the attenuation of high frequency signals, frequency response of the semiconducting layers voltages and the shield current are determined, While a calibrator signal generator, is employed during these measurements. At the sending end of the single core and 3phase cables, voltages of semi-conducting layers and the currents of shield wires at sending end and receiving end are measured, and compared. The ATP frequency dependent cable model is employed for simulation of PD propagation in single phase cable and the results are verified against the measured data on an XLPE cable test setup of this work.

Investigation of partial discharge pulses propagation in single-core and three-phase XLPE cables Keywords:

Partial discharge , H.F. Signal Propagation , Semi conducting layers , XLPE cable , Detection , Propagation