Nelson River HVDC system Y2k issues

The Nelson River HVDC system consists of two bipoles and supplies 70% of Manitoba Hydro's total power. Manitoba Hydro appointed a Y2K Contingency Planning Working Group and two Task Forces, one for the Power Systems and Operations and the other for the business systems. The function of the Power Systems and Operations Task Force is to test all the equipment for Y2K compliance/readiness and recommend action for the noncompliant equipment. The inventory results showed that there were no critical devices affected by the Y2K problem in bipole 2 and pole 2 of bipole 1. Since 1989 new reactive power compensation equipment has been added/upgraded and the mercury arc valves have been replaced with thyristor valves. The new equipment contains one or more devices that may be affected by the Y2K problem. Most of these devices (90%) are located at Dorsey station. A brief summary of the affected devices is given. The contingency plans for dealing with this equipment are outlined.