Coordinated Control of PV, Battery, and Supercapacitor in DC Microgrid

Over the past decade the interest in the DC microgrids (MGs) has been steadily rising, due to its various qualities such as greater efficiency and reliability, easier control, and a more natural interaction with electronic loads, renewable energy sources, and energy storage systems. The use of battery backup for energy storage is essential due to the irregular solar irradiation. In this paper, the DC microgrid consists of PV, battery, and supercapacitor for reliable power supply to the load. The solar PV is connected to the DC bus via a DC-DC boost converter by employing the P&O MPPT algorithm for maximum power point tracking. The battery is used with a bidirectional DC-DC converter for the charging and discharging. Also, the supercapacitor is used with a bidirectional DC-DC converter to supply the load during the transient conditions, which further enhances the battery life. The simulations are performed using MATLAB/Simulink software and take into account the modeling of the solar PV, battery, and supercapacitor as well as the design parameters of the DC-DC boost converter and bidirectional DC-DC converter.