Model-free power control of front-end PFC AC/DC converter for on-board charger

In a two-stage on-board charger, the front-end PFC AC/DC converter with conventional dual closed-loop PI controller, which consists of a external voltage loop and a inner current loop, is used to perform ac/dc conversion and power factor correction. The main drawbacks are poor dynamic performance and insufficient anti-disturbance ability. Therefore, enhancing the dynamic performance of PFC AC/DC converter has become one of the key problems that need to be solved urgently. Inspired by the power control method of PFC AC/DC converter based on the differential flatness theory, model-free power control is introduced in this paper to further improve system dynamic performance and the robustness against model uncertainties, unknown disturbances and measurement noise. Therefore, the ultra-local model of PFC AC/DC converter is first established innovatively by using the input and output data of converter and the model-free power controller is then designed. Based on the abovementioned researches, the feasibility of the proposed model-free power control scheme of PFC AC/DC converter is confirmed through system simulation. Finally, the automatic code generation and efficiency evaluation of the model-free power controller are carried out and some valuable conclusions are shown.