With continuous technological advances, increasing competitiveness of renewable sources, and concerns about the environmental impacts of the energy matrix, the use of hybrid microgrids has been promoted. These generation microsystems, historically composed basically of fossil fuels as the main source, have experienced an energy revolution with the introduction of renewable and intermittent sources. However, with the introduction of these uncontrollable sources, the technical challenges to system stability, low diesel consumption, and security of supply increase. The main objective of this work is to develop an operation and control strategy for energy storage systems intended for application in hybrid microgrids with AC coupling. Throughout the work, a bibliographic review of the existing applications is carried out, as well as a proposal for modification and combination to create a new control strategy. This strategy, based on optimized indirect control of diesel generators, seeks to increase generation efficiency, reduce working time, and increase the introduction of renewable sources in the system. As a result, there is a significant reduction in diesel consumption, a decrease in the power output variance of the diesel generation system, and an increase in the average operating power, which ensures effective control of hybrid plants.

The reliability of energy supply is an important factor for end-users of electricity. Although many advances and efforts have been made by distribution companies to guarantee energy quality, weak feeders and grids are still usually found. As an alternative to minimize such problems, Battery Energy Storage Systems (BESSs) can be used to supply energy to users in the case of power outages or major energy quality problems. This paper presents test results on a real application scenario in a microgrid with different load configurations in the moment of interruption. The tests were compared to each other to analyze the impact found in each scenario. In addition to those, real unpremeditated cases of power quality problems were also discussed, and the performance of the utilized BESS was evaluated.

Battery energy storage systems (BESS) are increasingly recognized as critical flexibility resources in power systems with high shares of renewable energy. However, their large-scale deployment depends on regulatory arrangements capable of supporting bankable business models. In Brazil, this issue has gained urgency considering growing renewable curtailment and the expected introduction of a storage-focused Capacity Reserve Auction in 2026. This article compares the regulatory treatment of BESS in China, California, Canada, and Chile to identify which elements most effectively support investment viability, and which applies to the Brazilian context. The analysis is structured around three dimensions that are central to storage bankability: capacity remuneration, participation in ancillary services, and energy arbitrage. The results show that financeable storage deployment rarely emerges from a single regulatory instrument. Rather, successful frameworks combine predictable revenue components, legal clarity for multi-service participation, and stable rules for performance verification and settlement. China illustrates the limits of mandatory co-location policies despite their role in accelerating scale. California highlights the contribution of ancillary-service markets, but also the risk of value cannibalization as storage penetration increases. Chile demonstrates the importance of capacity recognition, while Canada shows both the opportunities and limitations of storage in hydro-dominated systems. The article argues that Brazil should adopt a hybrid regulatory framework that combines capacity accreditation, explicit stacking rules, and formal remuneration for ancillary services. By linking cross-jurisdictional regulatory comparison to the Brazilian policy debate, this study contributes to literature on an applied framework for BESS regulatory design in hydro-dominant and renewable-constrained systems.