Energy Management and Control of Combined Hybrid Energy Storage and Photovoltaic Systems in DC Microgrid Applications

This paper discusses an Energy Management Algorithm (EMA) integrated into the control structure of a combined hybrid energy storage and photovoltaic system designed for DC microgrid applications. The increasing use of DC-based appliances in residential and commercial settings has resulted in the emergence of distributed energy sources and Energy Storage Systems (ESS) that resemble DC sources. Moreover, the intermittent nature of photovoltaic generation has underscored the significance of energy storage systems. However, ensuring a consistent and dependable power supply requires efficient power-sharing schemes for multiple DC sources and loads. To address this issue, the Hybrid Energy Storage System (HESS) has been developed, comprising batteries and supercapacitors that offer high energy density and high power density, respectively. Closed-loop control regulates the DC link voltage to maintain the overall system power balance. The EMA takes into account variations in PV power, battery and supercapacitor state of charge (SoC), and changes in DC loads to optimize energy management. To validate the system’s performance, simulation studies were conducted in MATLAB/SIMULINK for multiple scenarios.