Research on the Dynamic Characteristics of Switching Power Supply

In the fields of using green energy such as PV system and Wind power system, the step-up DC-DC converter, witch is used to convert the power, is now attracting more and more attention. The response characteristics and stability of one are key points for the performance of the whole system. However, it is complex to analyze the dynamic characteristics and control design. In this paper, the dynamic model of full-bridge DC-DC converter is presented, and transfer functions of the converter are derived by using state-space averaging method. And then the improved PI controller is designed. Finally, a laboratory prototype circuit with input voltage 220V, output voltage 600V is implemented and results are shown to confirm the validity of the designed switching device.