Distributed hierarchical economic optimization approach of microgrid based on multi-agent leader-following consensus

Abstract

Considering the higher generation operation cost of distributed generations (DGs) and power purchase cost in microgrid, the discrete-time mean consensus protocol (DMCP) is improved by bringing in the power offset elimination term in this paper. Then an improved multi-agent leader-following consensus algorithm (IMLCA) is proposed. The total power balance can be realized by the algorithm, which make the incremental cost (IC) of DGs converge to the consensus value quickly. Besides, the active power output objective of DGs is optimized and the overall generation operation cost of the AC microgrid is lessened. Afterwards, the distributed hierarchical economic optimization approach of microgrid based on multi-agent leader-following consensus is studied. In this approach, a distributed hierarchical framework is constructed. The economic optimization management level emits the optimal active power output objective of DGs to the droop control level. Meantime, the optimal active power output objective computed by IMLCA is carried out by using the droop control level. Thus, the active power output of DGs is apportioned reasonably. Finally, the simulation model of five-DG operation is constructed for research. The simulation results suggest that the approach can achieve the economic cost optimization goal of the grid-connected microgrid and the IMLCA possesses the better transient response performance and steady-state computation accuracy.

Keywords

• Multi-agent consensus
• Microgrid
• Economic optimization
• Distributed hierarchical architecture