In multi-terminal DC distribution system, due to the diversity of operating points and the complexity of impedance environment, it is often difficult to provide sufficient improvement effect of stability by the active damping control with single point configuration in the converter station. In order to meet the multi-source configuration requirements of active damping in complex system, this paper takes the phase-shifted full-bridge DC converter as the research object from the perspective of load. On the basis of establishing the average equivalent circuit, the reduced-order impedance model and the transformation relation between input side and output side parallel impedances in low-frequency range, the origin of active damping control strategy using input voltage feedforward is traced, and the active damping control strategy of output voltage feedback is proposed. Finally, the dual-terminal DC distribution system is taken as the application abject, the accuracy of the reduced-order impedance model for the phase-shifted full-bridge DC converter and the effectiveness of the active damping strategy are verified by the time-domain simulation results, the small-signal eigenvalue trajectories and hardware-in-the-loop experiments.