Consensus Algorithm based Two-Level Control Design for a DC Microgrid

This paper presents two-level control of DC microgrid for proper voltage regulation and equal current sharing across the load. DC microgrid is emerging as an alternate solution for rural electrification but it needs a robust and stable control system for good quality power delivery and proper energy management. In this paper, four microgrids are joined together to form a cluster and jointly all four microgrids deliver equal current to a common load. Droop control is implemented as a local level control for the regularization of voltage and current sharing. In order to mitigate the deviations created by primary level, consensus algorithm is used for generating a universal voltage reference for all droop controllers. It has been found that in a two level control structure there is lesser voltage deviation and proper current sharing among the units as compared to only droop control.