A multifunctional complex droop control scheme for dynamic power management in hybrid DC microgrids

It is crucial for hybrid DC microgrids (MGs) to employ power management strategies that take into account the dynamic characteristics of all energy sources in the system. This paper proposes a novel complex droop control (CDC) for voltage control units in hybrid DC MGs, which enables flexible power management by providing the capability to adjust steady-state and dynamic power sharing in addition to damping provision by leveraging a multifunctional droop function. To accurately tune the splitting frequencies that determine the performance of dynamic power sharing, a novel design procedure based on a reduced-order DC MG model is proposed. To gain insight into the dominant oscillatory modes and the impact of the proposed control on the stability of the hybrid DC MG, a system-level small-signal analysis is also conducted. Offline and real-time simulations of the hybrid DC MG subjected to pulsed-power load variations reveal that the CDC can effectively share dynamic power, while improving voltage regulation and damping.

Automated summary

This paper proposes a novel complex droop control (CDC) for voltage control units in hybrid DC microgrids, which enables flexible power management and improved voltage regulation and damping. A novel design procedure based on a reduced-order DC microgrid model is introduced to accurately tune the splitting frequencies for dynamic power sharing. System-level small-signal analysis is conducted to study the dominant oscillatory modes and the impact of the proposed control on the stability of the hybrid DC microgrid. Offline and real-time simulations show that the CDC effectively shares dynamic power and improves voltage regulation and damping.