A Distributed Control Strategy with Fractional Order PI Controller for DC Microgrid

This paper presents a novel distributed consensus control strategy for stabilization of the buses voltages and energy balancing of the storage in DC microgrids. The proposed strategy works based on sparse communication graph in which the agents possess fractional order proportional integral (FOPI) dynamics. The FOPI controller is used for energy balancing energy storage (ES) systems and to regulate the average DC microgrid buses voltages. The proposed control strategy operates in both operation modes of DC microgrid: 1) islanded mode, -2) grid connected mode. In both modes the average voltage of DC microgrid converges to the microgrid desire reference voltage. The energy storages systems are controlled independently of the operating mode to achieve and maintain a balanced energy level. The simulation results demonstrate the performance of the control strategy in a case study of a 10 bus 380 V DC with intermittent photovoltaic generation.