Subtransmission system reliability worth assessment using the Monte Carlo simulation method

This paper describes a Monte Carlo simulation approach to subtransmission system reliability worth assessment for all the five load buses of an educational test system. Three types of component failure modes in the subtransmission system are considered. First-order active failures, first-order total failures and all the possible second-order overlapping failures are included in this paper. Especially, the simulation sequences of general overlapping outage and overlapping outage modes involving scheduled maintenance are modeled and presented in this paper. In addition, the effects of different failure modes on the total supply point expected cost (ECOST) and interrupted energy assessment rate (IEAR) are analyzed. Furthermore, the results of a series of simulations studying the impacts of various probability distributions for restoration times on the two supply point worth indices and their dispersion degrees are presented. The information presented here is expected to be useful for electric power utilities and planners in the decision-making stage.