High-step-up quadratic DC-DC converter based on switched capacitor and coupled inductor techniques

This paper proposes a non-isolated quadratic high-step-up DC-DC converter. A coupled inductor and a switched capacitor cell are implemented in its structure to increase voltage gain. Balancing the capacitor and the coupled inductor plays the role of the resonant tank, which solves the problem of reverse recovery losses of its diodes. In this structure, soft switching conditions are established for some diodes and MOSFET, which reduces the switching losses of the converter. With a low number of components, the proposed converter achieves a high voltage gain. The diode-capacitor clamp circuit is utilized to reduce the negative effects caused by the leakage inductance and recover the energy stored in it. The performance of the proposed converter is analyzed in the continuous and discontinuous conduction modes. An analysis of design considerations, including inductors and capacitors, is presented. In addition, an analysis of the efficiency of the proposed topology is provided. The proposed topology is compared in terms of voltage gain, voltage/current stress across semiconductor components, and converter efficiency with related topologies. Finally, a 210 W (20 V/420 V) laboratory prototype is presented to verify the proposed converter's mathematical analysis and performance.