[Objective] The output of renewable energy is characterized by randomness and volatility, which can negatively impact the stable operation of power grids when directly integrated. To improve the grid connection characteristics of renewable energy generation systems, a hybrid energy storage system (HESS) has been introduced. To fully utilize the energy density and power density advantages of the HESS in DC microgrids, this paper proposes a fuzzy logic-based second-order high-pass filter control strategy with variable time constants. [Methods] Firstly, a photovoltaic hybrid energy storage DC microgrid model was constructed. Secondly, the power allocation strategy for the microgrid was designed based on power balance relationships, along with corresponding control strategies for each unit. The photovoltaic generation unit used fuzzy control to rapidly track the maximum power point, improving the energy utilization efficiency of the photovoltaic system. The grid-connected inverter adopted a double closed-loop con