Adaptive Energy Management in Redundant Hybrid DC Microgrid for Pulse Load Mitigation

This paper investigates the real-time control and energy management of a dc microgrid incorporating hybrid energy sources with various loading schemes. In the proposed dc microgrid, a supercapacitor bank, a power buffer, and a pulse load are directly connected to a dc bus. The proposed system configuration highly improves the grid redundancy and reduces the total power losses. Moreover, the supercapacitor bank not only supplies the pulse load, but also supports the grid during transient periods when it is highly loaded. However, the energy management and control of such a system is more complex, since the heavy pulse load can cause high power pulsation and voltage drop. To reduce the adverse effects of the pulse load, a new real-time energy management system (EMS) with an adaptive energy calculator (AEC) based on the moving average measurement technique is developed. The proposed microgrid was implemented in hardware and experimentally tested. The results were compared with other methods, such as direct voltage control and continuous current averaging approaches. The results show that the developed EMS with AEC technique properly share the power and control the bus voltage under different loading conditions, while the adverse effects of the pulse load are highly reduced.