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Highlights • A virtual capacitor droop control (CDC) using fuzzy logic algorithm in multiple HESSs can adaptively adjust the droop coefficient, so as to eliminate the impact of the line impedance on the power splitting and improve the power sharing accuracy. This study has not been reported in previous work. • Both the small-signal model and eigenvalue analysis are presented to study the stability of the HESS system using CDC, investigate the impact of the droop coefficient variation on the system dynamics and determine an optimal range of the modified droop coefficient. This work has not been involved in the previous studies. Abstract In a DC microgrid, virtual capacitor droop control (CDC) can achieve power allocation according to different frequency characteristics of a hybrid energy storage system (HESS). However, the control performance may be easily affected by the line impedance. In this paper, an adaptive droop controller based on a fuzzy logic algorithm is proposed. By detecting the unbalanced power and the voltage deviation, the droop coefficient can be adaptively adjusted to mitigate the influence of the line impedance and achieve desirable power splitting in the HESS. Furthermore, the small-signal model of the HESS is established and the impact of the droop coefficient variation on the stability of the DC microgrid is exploited. The simulation results in PSCAD/EMTDC verify the effectiveness of the proposed adaptive droop controller. It has been proved that desirable power splitting can be obtained among multiple HESSs under different scenarios. [ABSTRACT FROM AUTHOR]