A seamless operation mode transition control strategy for a microgrid based on master-slave control

This paper proposes a control strategy that can realize seamless microgrid operation mode transition between grid-connected operation and stand-alone operation. The scenario of a microgrid based on master-slave control is considered, where the master distributed generation (DG) unit operates in different control schemes in different microgrid operation modes, while other slave DG units operate with power/current control all the time. The proposed control strategy focuses on the master DG unit, and contains the control state/reference compensation algorithm and separation switch control logic. The proposed method can effectively reduce the impact on the critical loads and DG units caused by microgrid operation mode transitions.