Voltage Regulation and Battery Stress-Reduction Strategy for DC microgrid

Abstract

This paper proposes a control strategy for Photovoltaic (PV) system and energy storage system (ESS) in an islanded DC microgrid. In contrast to conventional control techniques where the battery is mostly responsible for DC grid voltage regulation, the proposed strategy utilizes PV based controller separately in regulating the microgrid voltage when battery is fully charged and disconnected, consequently reducing the overcharging stress on the battery, thereby prolonging the battery-life. The simulation results show the efficacy of the proposed controller in regulating the DC bus voltage despite of varying irradiance conditions and varying load conditions.