Reliability Evaluation Method for the Electricity-gas Coupled System Considering Correlation

A reliability evaluation method for the electricity- gas coupled system considering correlation is proposed. Firstly, the point estimate method is applied to the system reliability evaluation process. Since correlated variables could not be used in the point estimate method directly, Nataf transformation is adopted to deal with the correlation. Then, a novel general method to solve the transformed correlation coefficient matrix in Nataf transformation efficiently is researched. Finally, an electricity-gas coupled system consisting of a modified IEEE-RBTS Bus6 NO.4 feeder system and a modified NGSIO node natural gas system is constructed, and results indicate effectiveness and high efficiency of the proposed method.