Limin Xu

With the rapid development of China’s electricity spot market, the participation of Integrated Energy Systems (IESs) with multi-energy complementarity has become an inevitable trend in future energy development. However, IESs face difficulties in effectively matching heterogeneous resource capabilities with the diverse requirements of the multi-timescale spot market. Therefore, this paper proposes an optimization strategy for integrated energy system operation based on the hierarchical dispatch of flexibility resources, aiming to enhance the adaptability of different resources to multi-period markets. Firstly, a quantitative flexibility assessment framework is established from three key dimensions—power regulation range, energy shifting capacity, and dynamic response speed—to evaluate the market adaptability of various adjustable resources. Subsequently, the flexibility assessment results are converted into dynamic market participation ratios, which are incorporated as constraints into a Model Predictive Control (MPC)-based optimization model. In the day-ahead scheduling stage, the model prioritizes meeting fundamental electricity demand while dynamically reserving a portion of flexible capacity for participation in more profitable intra-day and real-time market services. Case studies demonstrate that the proposed strategy achieves real-time computational feasibility, significantly improves the economic performance of park-level IESs, and maintains stable dispatch behavior under market uncertainties and forecast deviations. The results indicate that the proposed hierarchical flexibility-oriented dispatch framework provides a practical and scalable solution for enabling IES participation in multi-timescale electricity spot markets.