Hierarchical Control in Islanded DC Microgrids With Flexible Structures

Hierarchical architectures stacking primary, secondary, and tertiary layers are widely employed for the operation control of islanded dc microgrids (dcmGs) composed distribution generation units (DGUs), loads, power lines. However, a comprehensive analysis all put together is often missing. In this work, we remedy limitation by setting out top-to-bottom hierarchical architecture. Decentralized voltage controllers attached to DGUs form our primary layer. Governed an MPC-based energy management system (EMS), layer generates optimal references decision variables DGUs. particular, can turn on/off select their modes. An intermediary secondary translates EMS into appropriate signals required More specifically, provide solution, solves optimization problem embedding power-flow equations shown be always solvable. Since load voltages not directly enforced, uniqueness necessary produce reference powers handed down EMS. To aim, deduce novel condition based only on local parameters. Our framework, besides being applicable generic dcmG topologies, accommodate topological changes caused commands. Its functioning validated via simulations modified 16-bus system.