A Modified Droop-Based Control Technique for Voltage Regulation of a Hybrid Energy Storage System Based DC-Microgrid

Abstract

The effective function of a hybrid energy storage system for a DC microgrid is noticeably influenced by factors such as variation in bus voltage,state-of-charge(SOC) and optimal power sharing.The centralized method of control is prevalent for achieving it.However,centralized method of control is prone to single points of failure,shows slow response due to delay in communication and is not cost-friendly.The paper explains an easy yet potential stratergy which is decentralized in nature.The virtual resistance droop(VRD) caters to the need of the battery converter where as the virtual capacitance droop(VCD) supplies power to the supercapacitor converter thereby achieving an effective power-split. The voltage variation is appreciably eliminated when the system reaches steady state resulting in smooth functioning of super capacitor.The model is simulated in the MATLAB/Simulink platform to verify the test results.