Enumeration based reliability assessment algorithm considering nodal uncertainties

A novel fast enumeration based reliability assessment algorithm based on a probabilistic load flow approach considering nodal uncertainties is proposed in this paper. The frequency and duration indices for each load point and the expected energy not supplied as well as the expected interruption costs are derived with the proposed methodology. By reducing the number of necessary system states a huge decrease of computation time is achieved while maintaining an adequate degree of accuracy. In order to verify the accuracy and the computational expensiveness of the proposed algorithm a commercial available program is used to compare the calculation results of a utility driven sub transmission power system. It is demonstrated that a fast calculation of the load indices, including station originated outages, can be performed, based on uncertain nodal powers, for instance nodal injections from wind farms or other stochastic power system loads, with a high degree of accuracy.