A new technical step in underground links for 90 kV high voltage energy transportation

Since 1962, synthetic insulated power cables have been used in France for 63 and 90 kV networks, with over 700 km of links already in service and with excellent outcome of experience. This is in particular due to a qualification test procedure of the complete cable system plus accessories which ensures the intrinsic quality of the components and their perfect compatibility. Many evolutions have taken place in thirty years and, since 1987, the only material used for HV cable insulation has been cross-linked polyethylene. The new 90 kV power cable advances one step further, with a new reduction of insulation thickness and the use of aluminium screens. Innovation also includes the development of new accessories, with in particular, “one piece-premoulded” joints and synthetic material terminations. Simultaneously, from the experience acquired in medium voltage applications, a mechanized technique for high voltage link laying has been developed and validated, first in the laboratory, and then on the power network