A Graph-modeling Approach to Topology Simplification in Power Converters

In this study, we propose a topology simplification method (TSM) for power converters, based on graph theory, to improve efficiency and economics of converter design. In the proposed method, a directed graph is firstly established to model a converter circuits, from which the conceptually new converter adjacency matrix (CAM) is derived. Combined with the electrical features of power converters, a rule for electronics current paths is presented. Then the redundant components are eliminated based on the proposed TSM and a new CAM is obtained, which is converted to a new directed graph and thus a new converter topology with reduced components. In the process, the integrity of the current paths is preserved and the new topology contains all the current paths of the original converter. With the proposed TSM, the derivations of the existing single-ended primary-inductor converter (SEPIC) and current-fed dual active bridge (CF-DAB) converters are employed for theoretical verification. A novel single-phase Boost push-pull converter topology is designed, which is validated by experiments.