Coordination-Based Power Management Strategy for Hybrid AC/DC Microgrid

In this article, a coordination-based power management strategy based on the concept of consensus algorithm and consensus index for hybrid ac/dc microgrid is proposed for achieving three objectives: 1) accurate and precise active/reactive power sharing between all ac distributed generations (DGs) in the ac subgrid, ac voltage regulation, and ac frequency restoration; 2) accurate and precise power/current sharing between all dc DGs in dc subgrid and dc voltage regulation; 3) accurate power sharing among all the participating ac/dc DGs in the hybrid ac/dc microgrid. The distributed secondary control within the ac/dc subgrids generates the consensus index, and the power management inside the two subgrids is achieved via the distributed control and the consensus index. Moreover, the bidirectional interlinking converter (BIC) control effectively operates with solely two consensus indexes, one from each ac/dc subgrid. Using these two consensus indexes, BIC establishes a dynamic interconnection between all participating DGs within the respective ac/dc subgrids, facilitating seamless power management among them. Compared to the existing strategies, the proposed strategy achieves accurate and proportional power sharing between all the participating ac and dc DGs in the system, rather than only achieving accurate and proportionate power sharing inside the two subgrids. Finally, the proposed power management strategy can considerably reduce communication data, complexity, and bandwidth.