Enhancing Stability of AC-DC Microgrid Cluster and Reducing Diesel Dependency With BSS

Renewable integrated microgrids face significant challenges, including stability issues during transient voltage fluctuations and reliance on diesel generators during islanded operations. Improving the reliability and efficiency of these systems is crucial. This paper presents an innovative control strategy for PV and wind-integrated microgrid cluster, focusing on enhancing stability and reducing diesel generator dependency. The proposed strategy utilizes a Double Second Order Generalized Integrator with an Enhanced Phase-Locked Loop (DSOGI-EPLL), referencing the frequency determined by droop control and a Localized Autonomous Controller (LAC).This configuration ensures precise synchronization and stable operation in grid-connected and islanded modes. A key feature of this strategy is LAC, which uses rule-based control logic to manage microgrid cluster operations dynamically. The LAC adjusts real-time operational modes and breaker configurations based on generation, load, and battery State of Charge (SoC). By integrating a Battery Storage System (BSS), the strategy significantly reduces dependence on diesel generators during grid outages. Stability during transitions from grid-connected to islanded modes is further improved by switching from DSOGI EPLL to droop control mode. The proposed strategy has been validated through simulations and Hardware-In-Loop (HIL) testing. In the HIL setup, the 2.5 kW wind turbine and 2 kW Battery Storage System (BSS) are considered as the hardware under test, while all other components, including the PV system, are validated through simulation. This demonstrated the practical feasibility and effectiveness of the strategy.