Enhanced schedule optimization with cross-scale coupling for microgrid with hybrid energy storage system

For multi-energy microgrid system incorporating a hybrid energy storage system (HESS) with battery and supercapacitor, developing economically optimized scheduling plans at both macro and micro time scales is crucial in long-term operation and short-term fluctuation stabilization. In consideration that supercapacitors handle fluctuations only at the micro scale (seconds/minutes), it is challenging to accurately quantify their economic impact at the macro-scale scheduling operations, which is usually overlooked. However, our investigations in this paper show that taking the supercapacitors’ transients into account is important and necessary for the system performance. Therefore, to address the challenge of scale confliction, this paper proposes an innovative cross-scale coupling optimization scheduling strategy. By utilization of the featured HESS-package model and adaptive iterative optimization (AIO) method for global promotion at the macro scale, and an improved filtration-based method with filter coefficients pre-optimization (FCPO) for in-depth enhancement at the micro scale, the HESS performance is coordinately optimized at both scales with more economical and sustainable management of the microgrid system. A case study with statistical analysis verifies a 12.79 % improvement with 95 % confidence interval (CI): [12.24 %, 13.33 %] in the economic benefits of the HESS microgrid at macro scale, meanwhile on the micro scale, day-lasting system fluctuations are successfully managed with an average 13.22 % (95 % CI: [12.04 %, 14.40 %]) reduction in HESS operating cost. Sensitivity analysis and scalability test confirm the robustness and adaptability of the proposed strategy across different HESS configurations and microgrid systems.