A novel soft-switched interleaved high step-up DC-DC converter for high-efficiency conversion

摘要

The present study aims to present a new interleaved soft-switched high step-up DC-DC converter, which is suitable for renewable energy sources, by integrating built-in transformer. A high conversion ratio is achieved by adjusting the turns ratio of the built-in transformer and duty cycle. The proposed converter uses active clamped circuit, which provides zero-voltage switching (ZVS) and a zero-current switching (ZCS) operation for all switches and diodes, respectively. Therefore, the losses caused by reverse recovery are considerably alleviated by providing ZCS condition in the diodes. The proposed structure has some advantages such as low-voltage stress across power switches, very low-input current ripple, fewer components, and lower cost. The MOSFET with low drain-source resistance can be used due to the low-voltage stress, which could reduce conduction losses. Furthermore, a 500-W, 48-V input to 380-V output laboratory prototype is built and tested to validate the performance of the proposed topology.