Resilience Enhancement Strategy of Electricity-Gas Integrated Energy System Based on Distributionally Robust Optimization

The frequent occurrence of extreme weather disaster events with low probability and high risk puts forward a great challenge to the safe and stable operation of the power system. Aiming at the deeply coupled electricity-gas integrated energy system, a resilience-oriented distributionally robust optimization model considering the failure probability information of distribution network transmission lines under extreme conditions is proposed to enhance the resilience. Firstly, the ambiguity set of the transmission line failure is constructed by incorporating the probability interval of component failure under extreme conditions. On this basis, an optimization problem of resilience enhancement in the distribution network is established with the tri-level framework of defense-attack-defense. Secondly, the operation feasibility sub-problem of the natural gas system is developed, where the power outputs of gas-fired units are regarded as the coupling variables. Thirdly, an internal and external bi-level cycle algorithm is proposed to solve the above problems: the outer cycle combines the duality theory and column-and-constraint generation algorithm to solve the distribution network optimization problem, and the Benders decomposition algorithm is employed to check the gas network problem in the inner cycle. Finally, the calculation example verifies the effectiveness of the proposed model and solution algorithm. © 2021 Automation of Electric Power Systems Press.