Distributed Hierarchical Control for Optimal Power Dispatch in Multiple DC Microgrids

Abstract

Coupling dc microgrids in close vicinity can minimize the total operating cost by full utilization of the generated power of the power systems. A fully distributed, consensus-based, and resilient hierarchical control scheme is proposed in this article to optimize the total generation cost of multiple dc microgrids by equalizing incremental costs of all distributed generators (DGs). The proposed scheme uses a sparse communication network in a fully distributed manner, which operates based on the neighbor-to-neighbor output feedback without requiring a central controller. In the proposed control scheme, optimal power sharing among DGs within a dc microgrid is met via the secondary controller. Additionally, the elimination of voltage deviation is accomplished in the secondary level without any influence on the optimal power sharing. The tertiary controller is responsible to realize optimal power sharing among dc microgrids. Simulation results illustrate the capability of the proposed strategy in equalizing incremental costs, not only among all DGs within a dc microgrid, but also among all dc microgrids. The performance of the proposed control scheme is evaluated by simulating multiple dc microgrids considering intermittent renewable DGs in PLECS software environment.