The Improvement of Dynamic Stability of DC Microgrids Using Decentralized Control System of Hybrid DG

In this paper, a decentralized control strategy based on the separation of the energy generation control unit is presented, which leads to stable operation and improve the DC micro-grid (MG) dynamic behavior. By applying the proposed control strategy, the fuel cell (FC) and supercapacitor (SC) units, which form a hybrid distributed generation (DG) source, are simultaneously controlled with independent controllers suggesting independent dynamic control performance. Moreover, in this control strategy, the SC unit, is supplied with a state-of-charge (SOC) regulator block to keep its proper performance. Accordingly, the dynamic separation of energy units affects the dynamic behavior of the overall DCMG and improves the system damping factor. By using the location analysis method of system eigenvalues, the proposed control strategy performance is evaluated. Also, the simulation studies in the PSCAD/IEMTDC software environment confirm the feasibility and proper performance of the proposed scheme.