Flexible Consensus Mechanism for Current Allocation in DC Microgrid

Renewable energy sources (RESs) have become the predominant trend in the development of energy systems in many countries. To coordinate RESs, microgrids have emerged as an efficient and optimal solution. However, the microgrid is facing the problem of inaccurate power sharing between the generators. To address the issue, this paper proposes a control technique that combines a dynamic consensus with droop control algorithms. The proposed method calculates current sharing error by utilizing current values and consensus algorithm. Then, an external current-sharing controller is adopted to regulate the droop parameter in an inner controller for improving the current sharing among RESs. By applying the proposed control method, the current sharing accuracy is achieved in the microgrid system under different load conditions. The proposed technique is analyzed and evaluated with the scale-down microgrid consisting of three distributed generators. The simulation results of the scale-down microgrid are obtained from the PLECS simulation platform.