A novel state selection technique for power system reliability evaluation

摘要

Only credible system states up to a certain contingency level are usually investigated in the reliability evaluation of power systems. The probabilities of some high level outage states may be larger than those of some low level outage states since system components may be not identical. The number of these high level outages with relatively large probabilities can be very large in a practical system. Their impact on system reliability can be very significant. However these high level outage states are ignored in the existing state selection techniques. The problem can be solved by the novel state selection technique proposed in this paper. In this technique, a pre-process has been used to arrange system components based on their availabilities in ascending order. A fast sorting algorithm (FSA) has been derived to quickly select the required number of the system states in descending probability order with the minimum number of computations and comparisons. For the given number of system states to be considered, the accuracy of reliability indices obtained using the proposed technique is much higher than that using the existing techniques. On the other hand, for the same accuracy the number of system states to be evaluated using the proposed technique is much less than that using the existing technique. The proposed technique has been illustrated by the IEEE-RTS.