Abstract
The supply reliability of the power system strongly depends on the system planning and operation. Under the competitive environment, system planning and operation become more complicated and difficult due to the new uncertainties that have not been considered so far. Which may also results in the enlargement of difficulties in forecast in the planning stage, and causes the deterioration of supply reliability. In the competitive environment, the transmission network must be planned and operated with the economical rationality and fairness. However, it is difficult to realize the system planning and operation considering the economical rationality and fairness because of the uncertainties. Then, the high flexibility and robustness against the uncertainties are required for the system planning and operation. This paper evaluates the performance of system expansion planning from two points of views: the probabilistic supply reliability and transmission margin in power system. As indices, the Expected Energy Not Supplied (EENS) and Available Transmission Capability (ATC) are used in this study.
