HVDC transmission system models for power system reliability evaluation

High voltage direct current transmission (HVDC) systems are finding increased use for long distance transmission of electrical energy from remote hydro electric generating stations to the load centers. The area of reliability evaluation of HVDC transmission systems has not attracted much attention in the past. The situation is changing as more and more DC links are being built, the need to develop methods for assessing the impact of these links on the overall system adequacy is increasing. This paper illustrates a technique for modeling the HVDC links. These models were then integrated into the overall system reliability studies. A simple system example was used to illustrate the technique. Practical system studies incorporating the developed model are illustrated. Finally the data requirements for modeling HVDC links in reliability studies are discussed.