Suchart JANJORNMANIT, Suttichai PREMRUDEEPREECHACHARN

A power sharing control for microgrids based on extrapolation of injecting powerand power-angle control

Droop controlled power sharing with an assumption that the value of line impedance is unavailable has beenproven to have limitations; the power sharing is problematic in systems with signi cantly resistive lines. Furthermore,when the droop is applied in the islanding mode of operation of a microgrid, the system is likely to become unstable. Inthis paper, the droop control is replaced by an analytical solution. The proposed approach of power sharing is power-angle control of distributed generators (DGs), such as voltage source converters, a type of DG with extrapolation ofpower injected to the connected bus. It is demonstrated that the power injection to the bus could be tracked within theDG's capacity autonomously. Simulation and experimental results demonstrate the validity of the approach and it isshown that the proposed approach is suitable for DGs with either inductive or resistive line impedance. Moreover, thismethod can be operated in complex networks, such as meshed networks.

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