A new family of cascaded high-order DC–DC converters for renewable energy applications
摘要
This paper proposes a non-isolated high step-up DC–DC converter suitable for renewable energy systems. The proposed topology, based on the concept of high-order coupling, integrates a secondary winding, a coupled inductor, a switched capacitor, and a voltage multiplier cell. Compared with conventional quadratic converters, the proposed converter achieves a high voltage gain while significantly reducing the turns ratio and lower duty cycle, thereby minimizing the size of magnetic components and improving overall compactness. Furthermore, the converter exhibits low voltage stress across semiconductor devices (including both switches and diodes), high efficiency, and a common-ground configuration. A comprehensive performance comparison with existing topologies of the same type is also presented. In addition, a reduction-order method for small-signal modeling of multi-winding cascaded converters is proposed. To validate the theoretical analysis, a laboratory prototype with an input voltage of 24 V and an output voltage of 400 V was built with peak efficiency of 95.83%. Experimental results confirm the correctness of the derived model and demonstrate the converter’s suitability for applications requiring high step-up ratios and high efficiency.