Energy Management and DC Bus Voltage Stabilization in a HRES Based DC Microgrid Using HESS

Abstract

This paper proposes a control strategy with stability analysis for a hybrid energy storage system (HESS) in a DC microgrid (DCMG) consisting of hybrid renewable energy sources (HRESs). The proposed control strategy effectively regulates DC bus voltage (DBV), maintains a balance in demand-generation and improves the power quality by flattening the intermittency in PV generation. The proposed configuration harnesses the advantage of both battery energy storage system (BESS) and supercapacitor (SC) energy storage system (SCESS) in the HESS through their effective utilization as per their power and energy densities. A filtration-based control (FBC) has been proposed using PI controllers to generate the reference signals as per inherent internal characteristics of BESS and SCESS. The efficacy of the proposed configuration is analyzed through simulations using Simscape™ module of MATLAB® software. The results are further validated using the FPGA-based real-time simulator Opal-RT.