Modeling, control study, and power management strategy of a hybrid grid-connected AC/DC microgrid with high integration of renewable energies and green hydrogen sources

Abstract

Abstract This first quarter of the 21st century is increasingly marked by population growth, digital and industrial developments, a growing need for electricity supply, and climate change. All these, to name just a few, have made the establishment of a stable, flexible, controlled, well-designed, extensive, and clean power system a necessity. Consequently, distributed microgrid generation based on alternative/renewable energies and/or low-carbon technologies has emerged. In this paper, we study the modeling, the control, and the power management strategy of a grid-connected hybrid alternating/direct current (AC/DC) microgrid based on a wind turbine generation system using a doubly fed induction generator, a photovoltaic generation system, and storage elements including hydrogen storage system and batteries. Adequate modeling is described, and the overall system monitoring is presented and applied to manage appropriate power sharing and to control active and reactive powers, in order to match load and weather fluctuation behavior. Simulations are carried out using a MATLAB/Simulink simulation tool. Simulations reveal convenient results in terms of the bidirectional interlinking converter capabilities regarding power balance establishment between the two subgrids, reactive power compensation to ensure a unity power factor, and DC-bus voltage regulation at 1200 V. In addition, the primary and secondary controls are approved for each distributed generation of the studied system to attain the assigned power references, regardless of whether the subgrid is heavily or lightly loaded throughout the four considered case studies, showing satisfactory tracking and interacting performances, and thus stimulating a stable system implementation.