A Meshed Hybrid Microgrid Configuration with Unified Power Quality Conditioner

The distribution grid is under major transformation due to the increasing dependency on renewable energy resources (RES) and electric vehicle (EV) charging stations. For accommodating such sources and loads in an existing AC distribution system without violating the voltage and current quality limits, various strategies such as modifying the control methodologies, structural reconfiguration of the grids, etc., are identified as suitable options. The power electronic converters play a significant role in integrating these features to the distribution grid. Unified power quality conditioner (UPQC) is a preferred choice to control quality of both currents and voltages. In this paper, the operation of a meshed hybrid microgrid is realized using UPQC. The DC link of UPQC is used to form a low voltage (LV) DC line. This LVDC line is connected parallel to the LVAC lines. The loads and distribution generation units are integrated to AC and DC lines using power electronic converters. The improved performance during adverse operating conditions show the superior reliability for the proposed system. In addition, the analysis verifies the enhanced capability of the proposed system in accommodating new DC loads to the existing system. Both simulation and experimental results are demonstrated to evaluate the performance of the proposed system.