Novel Interlinking Converter Approach for Islanded Hybrid Microgrids Based on the Modular Dual-Purpose Power Converter

The necessity of efficient and reliable renewable-based energy generation and distribution systems are turning the attention of researchers towards the hybrid ac/dc microgrid. This approach serves as a practical intermediate solution towards a fully dc distributed grid, as the majority of renewable energy assets such as photovoltaic generators, energy storage systems or electric vehicle charges operate in dc. In this paper, a novel concept of interlinking converter interfacing the ac and the dc buses of an islanded hybrid microgrid is studied. This approach relies on the recently proposed three-phase modular dual-purpose power converter, which is intended to be a universal power converter solution capable of performing both buck/boost operation for either dc-dc or dc-ac conversion while maintaining high modularity and minimum redundancy. The feasibility of this concept was demonstrated by designing a robust state-of-the-art control strategy for the islanded hybrid ac/dc microgrid coordination. The results verify the effectiveness of the proposed interlinking converter during real-time operation, which were obtained by means of hardware-in-the-loop tests.