To rapidly and accurately analyze the influences of randomness and correlation of wind speeds and loads on the reliability of an electricity-gas integrated energy system

a probabilistic reliability evaluation method based on the point estimation method and Nataf inverse transformation is proposed. The point estimation method

in which the probability problem is transformed into the deterministic problem that can be solved by the analytical method

is applied to the probabilistic reliability evaluation of the electricity-gas integrated energy system. The wind speeds and loads are processed by the Nataf inverse transformation

and a new general method for solving the transformed correlation matrix more conveniently and efficiently is researched

by which the point estimation method can be adopted to deal with the correlated variables in the electricity-gas integrated energy system. Finally

the effectiveness of the proposed method is verified by the reliability evaluation of the electricity-gas integrated energy system consisting of a modified IEEE RBTS-Bus6 feeder F4 system and a modified NGS10 natural gas system

and the results indicate that the effect of correlation on the reliability evaluation of the electricity-gas integrated energy system should be considered.