ABB Review Special Report - ABB - ABB Group

of this project was completed in July2000.The main components delivered for theproject were:Submarine cables between Franceand Jersey and between Jersey andGuernsey (approx 70 km)Underground cables on Jersey andGuernseyGIS substationsNew transformers and reactors6Storage of submarine cable prior to layingThe two submarine cables are of thesame basic design, ie three-core, separatelead-sheathed, and with tripleextrudedXLPE insulation. Each has afiber optic cable with 24 fibers integratedin it for system communication andinter-tripping. The cables have doublewire armor (ie, an inner layer of tensilearmor and an outer, so-called rockarmor) to protect them from damagethat could be caused by tidal currentsand fishing.The cables have a diameter of approximately250 mm and weigh about85 kg/m in air.Both cables were delivered by the factoryin their full lengths 6 .Because of the risks posed by fishingactivities, the cables between Jersey andGuernsey and the fiber optic cables betweenJersey and France were jetted intothe seabed for extra protection.Another submarine cable project is theMa Wan and Kap Shui Mun Cable,which crosses a channel in Hong Kong.Due to the heavy traffic in this channel,it was decided to forgo conventionalinstallation of the 132-kV and 11-kVsystems, which would probably havedisturbed shipping even if modern techniqueswere used. The problem wassolved by drilling under the seabed andinstalling ducts through which thecables were pulled. This has the extraadvantage of allowing upgrades to becarried out in the future.Separate control systems were installedto monitor operation of the cable link,which was completed in 2003.A new submarine cable project hasrecently been awarded to ABB byAramco. The cable, which is 53 kmlong, is rated 110 kV with 3 ž 500 mm 2copper conductors. It will be commissionedin 2004.HVDC Light TMHVDC Light TM , which was launched in1997, is another ABB innovation in theT&D field that incorporates advancedHV cable technology. High VoltageDirect Current (HVDC) cables are employedfor bulk power transportationover long distances, mainly underwater.Traditional cable technology is basedon paper insulation systems impregnatedwith highly viscous oil. While thesecables have many technical advantages,the manufacturing process is slow andthe end-product is mechanically sensitive.The industry had therefore beenlooking for a long time for an extrudedHVDC cable of the kind used in ACsystems.With HVDC Light [2], ABB has introducedto the market an extruded cablesystem, together with new transistorbasedconverters, that makes HVDCSpecial ReportABB Review51