it has become a tendency for energy structure adjustment that natural gas is taking the place of coal. The tight coupling of natural gas system with power system is even strengthened by the proposition of the “Energy Internet”. Traditionally
neglect of the influence of the power system-oriented optimal power flow under the constraints for natural gas system safe operation can lead to an over-optimistic solution. A combined natural gas and electric optimal power flow model is proposed with minimized total cost as the objective while considering all constraints on both systems. To tackle the uncertainty as well as correlation with input variables
a three point estimate method based on Nataf transformation is adopted. Finally
the model is verified on a modified IEEE 39-bus system and modified Belgian 20-bus natural gas system. Different volatility levels and correlations are analyzed. This work is supported by National Natural Science Foundation of China (No. 51277052