### A Novel Optimal Control Strategy for Energy Management in a Hybrid Microgrid System

#### Abstract

*This paper presents an optimal control technique for cost-effective microgrid operation that guarantees system stability in both off-grid and on-grid modes. This work proposes an evolutionary algorithmic approach to increasing power generation from renewable energy sources while minimizing losses. The system's loadability is enhanced, and general system limits and stability requirements such as the line stability index, voltage stability index, and small-signal stability are taken into account to achieve the best possible penetration of renewable energy. The proposed control method is employed in a campus microgrid and a microgrid integrated with the Indian (Kerala) power system. In off-grid mode, the renewable energy penetration into the microgrid is boosted to 87.5% more than the base scenario by enhancing system loadability to 94.9%, while in on-grid mode, the renewable power contribution improves by 46% more than the base scenario with an additional 9.4% of loadability. The results demonstrate that by maximizing renewable penetration, reducing power losses, and ensuring system stability in both off-grid and on-grid modes, a cost-effective and stable microgrid operation is achieved. Furthermore, grid integration and optimal loading enhance system performance.*

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