An adaptive power distributed control method to ensure proportional load power sharing in DC microgrid considering equivalent line impedances

This paper proposed a distributed control method for dc microgrid to ensure the proportional load sharing by taking into account the different line impedance. In the proposed method, the operation point of each DG is effectively defined based on the power rating and the instantaneous power of the DG to achieve the proportional load power sharing. A low bandwidth communication is used to transmit the data required to determine the power reference for all DGs. In order to balance the power per unit requirement, the output voltage of each DG is controlled by a power controller to adjust the desired operating point. Therefore, all DGs can operate at the balanced operating point on the droop curve to ensure the proportional load power sharing. This paper also considers the load shedding to prevent the dc microgrid from operating under overload condition. The effectiveness of the proposed method is verified by simulation and experiment which are carried out with 2.8kW prototype dc microgrid.