A Novel Isolated High-Step-Up Interleaved Converter for Renewable Energy Systems

In this article, an isolated high-step-up interleaved converter for renewable energy systems is proposed. The input-parallel configuration is introduced by two energy storage inductors, which can disperse the input current, reducing conduction losses, and also improve the conversion efficiency. In order to improve the voltage gain and recover the energy stored in the leakage inductance, the auxiliary step-up structure is utilized in the proposed converter, which includes an auxiliary inductor, an auxiliary capacitor, a voltage multiplier capacitor, and two switches that serve to exchange the energy stored in auxiliary capacitors and inductors. On the secondary side, a voltage-doubler circuit is used to extend the voltage gain. Finally, a prototype with an input voltage of 48 V, an output voltage of 400 V, and the rated power of 500 W is implemented to verified the effectiveness of the proposed converter. The experimental results show that the maximum efficiency is 95.97%, and the efficiency of full load is 93.27%.