Integrated Nonlinear Hierarchical Control and Management of Hybrid AC/DC Microgrids

Increasing the usage of distributed generations (DGs) leads the microgrids (MGs) to develop. Considering the existence of alternating current (ac) loads and sources and concerning increasing direct current (dc) loads and sources, hybrid ac/dc MGs have been used to have the advantages of both ac and dc MGs and reduce the drawbacks of them. By integrating the DG units in hybrid ac/dc MGs. Hence, a proper control method is required in such MGs to achieve precise voltage regulation and power-sharing, desired power quality, high efficiency, and high reliability. This article focused on nonlinear exponential control and distributed secondary control schemes to properly control the MG and form an integrated nonlinear hierarchical control and management for hybrid ac/dc MGs. Finally, to evaluate the proposed nonlinear control strategy's performance, offline digital time-domain simulation studies are carried out on a test MG system in MATLAB/Simulink environment. The results are also compared with previously reported methods. The simulation results and the comparisons showed that the proposed methods could properly share the power among subgrids and DGs in both ac and dc subgrids. In contrast, the proposed control scheme can prove its effectiveness and superiority over conventional controllers.