Robust Energy Management for Microgrids With High-Penetration Renewables

TLDR

Distributed energy management is crucial in smart grids, particularly in microgrids with distributed generation and storage, because it reduces communication overhead and improves robustness to failures. The study investigates distributed economic dispatch for a high‑renewable microgrid with demand‑side management in grid‑connected mode, proposing a novel power‑scheduling approach to handle stochastic renewable availability. The authors develop a distributed scheduling strategy that integrates actual renewable output and grid trades, minimizes net cost—including DG, DS, load utility, and worst‑case transaction costs—and solves the problem via dual decomposition across local controllers. Simulation results demonstrate the effectiveness of the proposed scheduling method.

Abstract

Due to its reduced communication overhead and robustness to failures, distributed energy management is of paramount importance in smart grids, especially in microgrids, which feature distributed generation (DG) and distributed storage (DS). Distributed economic dispatch for a microgrid with high renewable energy penetration and demand-side management operating in grid-connected mode is considered in this paper. To address the intrinsically stochastic availability of renewable energy sources (RES), a novel power scheduling approach is introduced. The approach involves the actual renewable energy as well as the energy traded with the main grid, so that the supply-demand balance is maintained. The optimal scheduling strategy minimizes the microgrid net cost, which includes DG and DS costs, utility of dispatchable loads, and worst-case transaction cost stemming from the uncertainty in RES. Leveraging the dual decomposition, the optimization problem formulated is solved in a distributed fashion by the local controllers of DG, DS, and dispatchable loads. Numerical results are reported to corroborate the effectiveness of the novel approach.