Multi-time-scale Optimal Scheduling of Integrated Energy System Considering Multi-energy Flexibility

The complex energy conversion relationship and the volatility of renewable energy and load in an integrated energy system containing electricity, heat and gas have brought challenges to the flexible and safe operation of the integrated energy system. In order to reduce the impact of renewable energy and load uncertainty on the system, and improve the power suppression capacity of the system at the same time, a multi-time-scale optimal scheduling strategy for an integrated energy system that considers multi-energy flexibility is proposed. First, in the day-ahead scheduling, a multi-energy flexibility state equation is established, and a scheduling model that takes the system multi-energy flexibility into account in the fluctuation scenario with the minimum daily operation cost is constructed. The intraday scheduling is based on the day-ahead scheduling results. Considering the responsiveness of electricity, heat, gas energy on different time scales, a multi-time-scale rolling optimal model is established to revise the previous plan to suppress the power fluctuation. The results of the calculation examples show that the proposed day-ahead model can improve the system operation flexibility by coordinating the output of different devices, and the intraday model can suppress the power fluctuation of electricity, heat and gas energy at different time scales. © 2021 Automation of Electric Power Systems Press.