Power flow management algorithms for centralized controller in direct-current microgrid

Abstract

DC microgrids are definitely one of the global trends shaping the future of the energy sector. The prospective spread of distributed power generation systems raises the need for an optimized multilayer power management control structure in DC microgrids. The main topic of the article is modular control strategy for a centralized controller in a direct-current microgrid. The paper presents four power flow management algorithms allowing microgrid to operate in autonomous mode. Control algorithms ensure DC-bus voltage ripple compensation, maximum PV power point tracking, reduction of energy storage degradation and constraints for power exchange with the electrical grid. The topology structure of the microgrid with AC/DC and DC/DC modular converters is proposed for the distributed power technology. Furthermore, a simulation model consisting of PV power generation, hybrid energy storage, low voltage grid connection and EV fast-charging station submodels are presented. Simulation results are described to validate the effectiveness of the proposed hierarchical power management control structure.