Control and Improvement of Power Quality in Hybrid Three-Terminal AC/DC Microgrids

Nowadays, the use of renewable energy sources has gained more attention due to their lower pollution ‎and cost compared to traditional fossil fuel generators. Microgrid (MG) structures are used for better ‎management of these resources. This article focuses on power control in three-terminal AC/DC hybrid ‎MGs. For this purpose, a network backup converter is used to improve power sharing and reduce power ‎quality disturbances. The components of the MG include distributed generation units, AC loads, DC ‎loads, energy storage system (battery), and parallel connecting converters. In the studied topology of ‎AC/DC hybrid MG in this article, there are two main converters: a grid-forming converter that acts as ‎an intermediary converter and is used to control the MG voltage, and a VSC converter that is located ‎between the DC link (including the DC MG and battery) and the AC MG. In this article, a control ‎system is implemented for a hybrid MG and simulations are performed in MATLAB software for ‎four different scenarios related to active and reactive power of the MG and loads. Simulation results ‎show that the energy management system and power control in the AC/DC hybrid MG have reduced ‎harmonics and improved system reliability in the MG.