Different Measurement Setup Configurations for Space Charge test in Mini Cable Specimens with the PEA Method

Under DC stress, the space charge accumulation is believed one of the most responsible of dielectrics ageing. For this reason, due to the increase of the HVDC transmission, a recommendation has been proposed. The latter want to introduce the space charge measure, with the PEA method, in cable specimens during the prequalification or type tests. Considering the several issues related to this kind of measures the aim of the proposed work is find a measurement setup for mini cable specimens which is able to provide a clear and clean space charge profile. Therefore, different tests have been made in this work. In particular, the length of the cable specimen, the width of the pulse electrodes, as well as the distance between the pulse electrodes position and the cell measuring point, have been evaluated. Measurement results shown that the best solution is for a mini cable 2 m length and when the pulse electrodes width and its distance from the measuring point is equal to 20 cm.