Modelling and control design of a dual Buck-Boost AC/DC converter used in the DC Nano-grid

Due to widely used DC characterized loads and more distributed power generation sources, the DC Nano-grid becomes more and more popular and seen as an alternative to the AC-grid in future. For the safety considerations, the DC Nano-grid should provide reliable grounding for the residential loads like the low voltage AC power system. In this paper, a dual Buck-Boost AC/DC converter for use in the united grounding configuration based DC Nano-grid with three terminal outputs is proposed. It will be much easy to construct an efficient DC Nano-grid based on the existing low AC power system by using the proposed converter. The working principle of this converter and the system modeling are presented in detail. Simulations are carried out to verify the theoretical analysis.