The converters are widely used in distributed power generation systems. The input & output impedance and control loop designs of all levels converter should be considered together for the dynamic and static characteristics both of converters and system integration. As one kind of the Buck mode converters, the phase-shift full bridge DC-DC converters are widely used in high frequency and high power field. Compared with voltage control mode, the average current control mode could make the converters get better dynamic and static characteristics. Based on average current control mode phase-shift full bridge DC-DC converter as an example, the relationship between the closed-loop output impedance and control loop parameters is revealed in the paper, the current and voltage loop compensation network parameters design rules also are discussed. In condition of the dynamic and static characteristics of the single stage converter, closed-loop output impedance rush of converter is also constraint to ensure stable and reliable work after system integration. System simulation and experimental results verified the theoretical analysis.