Optimal load balancing strategy for hybrid energy management system in DC microgrid with PV, fuel cell and battery storage

This paper presents a novel strategy for a hybrid energy management system consisting of a photovoltaic (PV) array, a polymer electrolyte membrane fuel cell (PEM-FC) as energy sources and Lithium ion (Li-ion) battery as an auxiliary energy storage. Such hybrid combination brings the reliability, redundancy and an overall energy efficiency in the system. DC-DC converters are used to interface PV-FC-battery combination. Energy management between the three sources is done by operating them in three different modes based on power requirement of load. PV operates in maximum power point tracking (MPPT) or desired power control (DPC) mode. Battery operates in voltage control mode simultaneously maintaining its state of charge (SOC) and maintains the DC link. Fuel cell (FC) operates in Power control modes (PCM). The active power demand is controlled by regulating DC link voltage. The system is simulated in MATLAB/Simulink for all operations and the results are presented along with modelling, analysis and frequency based control design.