An Adaptive Decentralized Power Management Strategy for Enhancing Transient and Steady-State Performance of Hybrid AC-DC Microgrids

In hybrid ac-dc microgrids (HMGs), the transient and steady-state performance of ac frequency and dc voltage can be improved by the virtual inertia enhancement and reasonable power management control, respectively. This article proposes an adaptive decentralized power management strategy for the HMG to enhance both the transient performance and the steady-state performance. For ac and dc subgrids, virtual inertia equations on both the subgrids are used to slow down the changes in ac frequency and dc voltage individually. For the bidirectional interlinking converter (BILC), bidirectional virtual inertia enhancement between two subgrids is achieved by the adaptive coordinated power control (ACPC), thus improving the dynamic responses of HMGs when power fluctuates. Besides, with the help of ACPC, the priority of ac frequency control and dc voltage control in power fluctuation responses is determined by the defined adaptive weight factor, thus enabling the BILC to support the side with a larger ac frequency or dc voltage deviation in priority. In this way, the global variation index of ac frequency and dc voltage deviations is minimized, ensuring the optimal stable power quality. Finally, the efficacy of the proposed control is validated by the comparative simulation and hardware-in-the-loop results.