Typical defect simulation of 110kV cable and its partial discharge characteristic test

In order to investigate the causes of joint breakdown caused by high voltage cables partial discharge, the five kinds of cable body defects: the insulation shield fracture stripping irregular, the main insulation of the insulation shield fracture being cut, the insulation shield fracture has steps, the main insulation is inserted with the metal tip, and the main insulation having air holes, as well as the two kinds of defects in the accessories: the dislocation of the stress cone and the impurity in the stress cone for 110kV XLPE insulated cable joint, the simulation were made. Then the boost test was carried out in the high pressure test hall, and the test samples were monitored by the partial discharge detection system based on the broadband pulse current method. The analysis of the partial discharge characteristics of various typical defects shows that controlling the installation quality of the cable body and accessories during installation is the direct means to reduce the breakdown risk of the transition joints.