Comparison between different types of EHV and UHV transmission system taking account of their forced outages

Over the world there are large and economically attractive energy resources that are located at long (500 -1500 km) and very long (2000 - 4000 km) distances from load areas. Proceeding from the state of the art, the problem of power transmission over such distances can be solved with the help of EHV and UHV Transmission Systems of both DC and AC. Forced outages of TSs have a marked effect on the reliability of Interconnected Power System (IPS). The effect most strongly manifests itself when transmitted power is comparable with installed capacity of receiving system. An analytical method is proposed for evaluating the effect of TS forced outages on reliability of IPS using Loss of Load Probability and Lost Energy. When comparing alternatives, this method makes it possible to determine the extra amount of Present Worth Cost connected with Forced Outages of TS and required to ensure equal reliability level in each variant.