Control Schemes for Hybrid AC-DC Microgrid

With expanding usage of renewable energy sources, the popularity of microgrids (MG) is also on the rise. Research is ongoing in the field of hybrid MG to develop effective control strategies and stability assessments. Among the three types of MG architecture (AC-coupled, DC-coupled, and hybrid AC-DC coupled), the hybrid AC-DC coupled MG (HACDCMG) is preferred for its benefits. This study focuses on the hierarchical control system of the HACDCMG, which consists of three layers: primary, secondary, and tertiary control. The first one regulates current or voltage, while the secondary control system corrects voltage or current errors and manages power exchange in MG. The tertiary control system manages power sharing along with energy management. The study explores the efficacy of each MG architectural control method, including the coordinated control among multiple ILC and ESS and mode transition. The HACDCMG control method is particularly effective, and this study provides an in-depth analysis of its benefits.