Refurbishment strategies for HVDC projects

Several HVDC installations are presently undergoing refurbishment, while others have already been through refurbishment, and this paper will review the various strategies being adopted by the owners to extending the life of their plant. The projects covered by the paper include Nelson River (2000 MW Overhead Line Transmission), Konti-Skan Pole 1 (380 MW Cable + Line Transmission), McNeill (150 MW Back to Back), UK-France (2000 MW Cable), Haenam-Jeju Island (300 MW Cable). The approach for each project varies according to the owners need to minimize capital expenditure, while at the same time getting the maximum extended life, only replacing the parts of the system which are presently giving maintenance problems, or those that are expected to give maintenance problems in the near future. There is also a desire on the part of some owners to take advantage of new technology available today, which was not available at the time of the original construction. The scope and implementation plan for the refurbishment of each the above projects will be considered.