Two-Stage Load Transfer Strategy for Multi-Energy Multi-Microgrids Based on Energy Hub Modelling

Abstract

In the face of sudden load fluctuations or energy shortages, load transfer in multi-energy multi-microgrid (MMG) plays a critical role in ensuring energy supply security. Traditional MMG load transfer strategies typically prioritise minimising load shedding while often neglecting inter-multi-energy microgrid (MG) coordination and the regulation burden on energy devices. To address these limitations, this paper proposes a load transfer strategy for MMG systems based on the energy hub (EH) model. First, a comprehensive energy hub-based modelling framework is established for the MMG. Then, a two-stage load transfer strategy is introduced: the first stage addresses local energy shortages within individual MGs by leveraging internal resources; the second stage is activated when local resources are insufficient, enabling coordinated energy transfer across microgrids to alleviate multi-energy shortages from a system-wide perspective. Furthermore, energy flow path analysis is conducted to explore optimal energy routing and inter-MG interactions under different load scenarios. Simulation results demonstrate that, compared with conventional strategies, the proposed approach reduces operational cost variation by 10.06% and 7.63%, respectively, decreases the regulation burden on internal devices, and enables effective inter-MG load coordination. These results confirm the proposed method's effectiveness in enhancing the economic efficiency and operational stability of MMG.