A bidirectional buck-boost bipolar DC/DC converter with inductive dc link

A novel buck-boost converter for bipolar dc grids is proposed. In the proposed topology, an inductive dc link is used between the input and outputs. The inductive dc link is charged and discharged at the link frequency. The proposed converter's merits are: bidirectional power flow, soft switching, and step up/down conversion capability. Operating principles of the converter are presented and analytically modeled; moreover, a control strategy for bidirectional operation is proposed. To achieve a suitable startup and proper steady-state response, a fuzzy logic rule is employed in the PI controller. The proposed converter and the control strategy are verified through several simulations.