Cooperative Decentralized Hierarchical Based Voltage Control of DC Microgrids

This paper introduces a contemporary approach of cooperative decentralized control strategy of DC microgrids based on hierarchical paradigm to regulate power flow between grid terminals. This control structure comprises of primary, secondary and tertiary controllers, each of which is implemented at different time scales to mitigate operational terminal voltage at various grid locations with optimized generation cost. Distributed generations (DGs) are connected to the microgrid through highly efficient Line Regulating Converters (LRC). However, lack of transmission lines' current control might introduce successive violations of thermal and stability limits. Mitigating strategy is assigned to tertiary controller and the model is updated accordingly to regulate terminal voltages based on various overloading cases. The effectiveness of the proposed technique is verified using MATLAB/Simulink 2016b based on a composite DC microgrid test system.