Power sharing correction in angle droop controlled inverter interfaced microgrids

Power sharing between angle-droop controlled inverter-based sources largely depends on the line impedances and choice of droop coefficients. Simple power correction methods such as set-point correction and droop coefficient modification work satisfactorily for specific network topologies and require only limited amount of communication. However, their performance can be inadequate for microgrids with different topologies. In this work, we propose a topology-independent power sharing correction technique based on inter-node communications in order to eliminate the power sharing errors between inverters. We analyse stability and convergence of the proposed solution and present simulation results. Finally, we study the robustness of frequency-droop and angle-droop controlled systems with respect to unknown impedances and parameter uncertainties.

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