Dynamic consensus algorithm based distributed unbalance compensation in islanded microgrids

In islanded microgrids (MG), distributed generators (DG) can be employed as distributed compensators for improving the power quality in consumer side. A multi-level hierarchical control is usually applied with each level dealing with different issues. In case of voltage unbalance compensation, droop control and virtual impedance can be applied in primary control to help the basic active and reactive power sharing. Secondary control is used to assist voltage unbalance compensation. However, if transmission line differences are considered, the negative sequence current cannot be well shared among DGs. Accordingly, this paper proposes a dynamic consensus algorithm based distributed negative sequence current sharing method based on the modeling and analysis of the unbalanced system. Experimental results are shown to demonstrate the effectiveness of the method.