Distributed optimal scheduling for coupled transmission-distribution integrated electricity-gas system

The coordinated optimal scheduling of coupled transmission-distribution integrated electricity-gas system (CTD-IEGS) is of great significance to ensure the economy and security of the system operation. In this paper, an optimal scheduling model of CTD-IEGS is proposed. To deal with the influence of uncertainty on both trans-mission and distribution sides, a probabilistic reserve allocation model based on chance-constrained program-ming (CCP) method is proposed, and the discrete sequence transformation (DST) method is used to transform the CCP reserve constraints into an easy solvable deterministic form. Due to the interdependence between the transmission system operator (TSO) and distribution system operator (DSO), a distributed solution algorithm based on alternating direction method of multipliers (ADMM) is adopted to solve the optimal scheduling model of CTD-IEGS. Case studies show that the proposed distributed solution strategy can effectively realize the distributed scheduling and coordinated optimization of the transmission network and distribution network, and protect the information privacy of TSO and DSO. In addition, the CCP method can adjust the confidence level of reserve to meet the tolerance of transmission and distribution network decision-makers for different risks, and balance the operation economy and reliability of the system.