Three-port DC–DC converter based on quadratic boost converter for stand-alone PV/battery systems.

In this study, a three-port DC–DC converter is proposed based on quadratic boost converter. The proposed converter contains paths to enable the flow of power from input source to load and battery. Furthermore, it makes a path available to energise the load by the battery. The proposed converter has a bidirectional path using two additional switches and two diodes. Power flows from the input source and the battery to the load in a single-stage resulting in higher efficiency. The proposed converter has three switches and two duty cycles defined. By adjusting the duty cycles, maximum input power and output voltage can be regulated based on the input source power and the battery condition. To control the proposed converter, three operation modes are defined. In order to design the control system, the proposed converter is analysed and the small-signal models are obtained. Using a decoupling network for the integrated small-signal models, separated closed-loop controllers are designed. Finally, a prototype for the proposed converter is prepared to validate feasibility and effectiveness of the proposed converter and the control method by experimental results. [ABSTRACT FROM AUTHOR]