Power Management of Solar PV Battery and Supercapacitor in DC Microgrid

This paper presents an intelligent power management strategy for a DC microgrid integrating a solar photovoltaic (PV) system, battery storage, and a supercapacitor (SC) to ensure reliable and efficient energy distribution under fluctuating load and environmental conditions. The core challenge addressed is the coordination of diverse energy sources to maintain power balance and voltage stability. To optimize energy harvesting from the PV array, an Incremental Conductance (IC) Maximum Power Point Tracking (MPPT) algorithm is implemented, which accurately tracks the maximum power point (MPP) even under dynamic irradiance levels, achieving efficiencies of up to 99.9%. The battery functions as the primary energy buffer, absorbing excess energy during high solar generation and discharging during periods of low irradiance or high demand. The Supercapacitor complements the battery by handling transient load variations and providing immediate power support, thereby reducing stress and enhancing battery lifespan. A PI-based Power Management Control (PMC) dynamically adjusts the contribution from each source based on system parameters. Simulation results in MATLAB confirm that the proposed strategy maintains the DC bus voltage at a constant 400V and sustains a continuous load power of 1 kW, regardless of changes in solar irradiance. The battery and SC exhibit efficient and coordinated operation, ensuring uninterrupted power supply and improved energy efficiency. This proposed system is particularly suitable for remote or off-grid locations, offering a robust, scalable, and reliable solution for modern renewable energybased microgrid.