We have a number of recognized transmission and distribution experts serving on our board of "Grid Masters." Several times each month we’ll post what we judge to be the toughest questions that also have high interest to our readers. At least one of our experts will respond. Want to challenge our Grid Masters for a chance to win?

Q: What is the current state of the art with respect to repair joints for XLPE submarine cables at voltages AC and DC above 200kV?. Have any been installed in practice and what has the operational reliability been?
E. Bergin (Ireland)

A: ABB has designed and tested repair joints for 345 kV AC (Bayonne Energy Center), 420 kV AC (Lille Baelt project in Denmark) and 320 kV DC (DolWin 1). However, to date there have been no events that have required installation of such repair joints.
Michael Bahrman
HVDC Business Development
ABB

See previous questions and answers or join the discussion. Add your comments below: