Seamless Formation and Robust Control of Distributed Generation Microgrids via Direct Voltage Control and Optimized Dynamic Power Sharing

Seamless formation and robust control of distributed generation microgrids are essential requirements to facilitate powerful and flexible control infrastructure in future smart power grids. Motivated by this objective, this paper presents a control structure for microgrid converters based on direct-voltage control and optimized dynamic power sharing. The salient features of the proposed scheme are 1) minimum switching actions between grid-connected and isolated microgrids systems to minimize internal microgrid formation disturbances; 2) active damping control performance in the converter control voltage vector to effectively reject both voltage magnitude disturbances and power angle swings associated with mode transition and load disturbances; and 3) high bandwidth direct voltage control loop in both grid-connected and isolated microgrid modes to improve the dynamic response and disturbance rejection performance. Theoretical analysis and comparative experimental results are presented to validate the effectiveness of the proposed control scheme.

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