Energy management and operation modelling of hybrid AC–DC microgrid

TLDR

Hybrid AC–DC microgrids are envisioned as future distribution networks that combine the advantages of AC and DC, integrating AC and DC loads, renewable‑based distributed generators, controllable generators, and energy storage through separate AC and DC links. The study proposes an up‑down operation model for such hybrid microgrids that operates at both system and device levels. At the system level, a mixed‑integer linear model balances generation and load across AC and DC subgrids to minimize total operating cost over a 24‑hour horizon, while at the device level a controller for intergrid inverters and batteries regulates voltage variations in the AC and DC subgrids. Simulation results on a test hybrid microgrid confirm the effectiveness of the proposed up‑down operation model.

Abstract

Hybrid AC–DC microgrid is introduced as the future distribution network to utilise both benefits of alternative and direct currents. In such hybrid microgrid, AC and DC loads, renewable‐based distributed generators (DGs), controllable DGs and energy storage systems are connected through separate AC and DC links. An up–down operation model of such hybrid microgrid is proposed which consists of system‐ and device‐level. In the system‐level, a mixed integer linear model is suggested to balance the generation and load considering the interconnection of AC and DC subgrids for minimising total operating cost of the system in a 24‐hour period. In the device‐level, a controller is suggested for power converter‐based resources (i.e. intergrid inverter and battery) for controlling the voltage variations in AC and DC subgrids. The effectiveness of the proposed up–down operation model is demonstrated through simulation studies on a test hybrid microgrid.