Development of prefabricated type straight through joint for 275 kV XLPE cable

The research involved in developing a prefabricated-type straight-through joint for 275 kV cross-linked polyethylene (XLPE) cable is described. Based on a review of the results of electric field analysis, a compact insulation structure using a molded epoxy insulation unit and a molded ethylene propylene rubber (EPR) stress-relieving cone was designed. The AC and lightning impulse voltage test as well as the short-circuit test and the offset test were conducted on the joint developed. The results have shown that the joint possesses excellent assembly properties and superb insulation performance. The accelerated long-term aging test was also conducted for six months and provided verification that the joint developed has adequate long-term reliability