An Improved Droop Control Method to Improve Bus Voltage and Ensure Accurate Proportional Load Power Sharing in Isolated DC Microgrids

A new power sharing control method for a dc microgrid is presented in this paper. The control strategy can restore the bus voltage and achieve accurate proportional load power sharing according to the power capacity of distributed generators. To achieve this goal, power compensation was proposed according to the rated power and output power of distributed generators. The bus voltage deviation was reduced by adding voltage compensation. With the proposed scheme, only the output power of generators requires to transmit through low bandwidth communication lines. An isolated dc microgrid is simulated in MATLAB/Simulink environment to testify the effectiveness of the control strategy. The proposed control strategy can effectively realize the bus voltage restoration and enhance the power sharing accuracy compared with the conventional droop control method.