(1. College of Energy and Electrical Engineering, Hohai University, Nanjing 211100, China; 2. China Electric Power Research Institute, Beijing 100192, China)

Some power generation technologies such as gas-fired generator provide an effective way for low-carbon electricity. Meanwhile, Energy Internet enables a deep interconnection between the natural gas network and the electric power network. This paper proposes a joint economic operation model for integrated electricity and natural gas energy system. Minimizing the sum of integrated energy system generation energy costs and carbon trading costs becomes the objective function of the model with the consideration of the carbon trading mechanism. The security constraints of the natural gas and electricity networks are considered simultaneously. The test case consists of the modified IEEE 30-bus electric network, the Belgian 20-bus gas network and the couplings of gas-fired generators. The effectiveness of the proposed model has been verified by analyzing and comparing the operation conditions of integrated electricity and natural gas energy system and power system with all coal-fired generators based low-carbon economic model. Finally, the effect of carbon trading price, the price of natural gas and natural gas network constraints on operation conditions has been further analyzed. This work is supported by National Natural Science Foundation of China(No. 51277052).