Performance analysis of hybrid AC / DC microgrid under influence of battery energy storage location

Abstract

In microgrids, energy storage is generally located based on power management criteria and economic objectives that lean on the system's steady-state operation. However, the grid configuration, dynamics of primary energy sources, and storage type (AC or DC) impact its transient operation. This paper conducts a comparative study of the dynamic performance of Hybrid AC/DC Microgrids (HMGs) under the influence of Battery Energy Storage System (BESS) location, which has been neglected in the literature. The HMG performance is compared for one single BESS unit located either in AC or DC sub-grid during various grid operational cases, considering interlinking converter (ILC) control topology that alters depending on the type of BESS. Two types of microgrid case studies with different structures have been considered, that is, a high inertia HMG and a converter-interfaced low inertia HMG. Simulation results reveal that the HMGs with both BESS locations perform robustly in handling grid disruptions. However, the BESS located in the DC sub-grid of a high inertia microgrid case presents an average of 40% higher quality of performance in key performance indicators compared to that of the AC sub-grid BESS. Conversely, the performance of the low inertia HMG with the BESS connected to the AC sub-grid is superior to that of the DC sub-grid BESS, by an average of 65% and 54% in key performance indicators.