Tapped-inductor bi-directional Cuk converter with high step-up/down conversion ratio and its optimum design

Area of Science:

• Electrical Engineering
• Power Electronics
• Energy Storage Systems

Background:

• Bidirectional DC-DC converters are crucial for modern energy storage systems.
• Key development trends include high efficiency and wide voltage conversion ratios.
• Existing Cuk converter topologies may not meet these demanding requirements.

Purpose of the Study:

• To derive and propose a novel bidirectional high-gain Cuk converter.
• To enhance voltage gain and efficiency for energy storage applications.
• To analyze and optimize the performance of the proposed converter topology.

Main Methods:

• Derivation of a series of bidirectional high-gain Cuk circuits by integrating tapped inductors.
• Analysis and comparison of derived circuit characteristics.
• Establishment of a power loss model and optimization of the tapped-inductor turn ratio.

Main Results:

• A specific bidirectional high-gain Cuk circuit with a tapped-inductor (reverse coupling) was proposed.
• The proposed converter exhibits a simple structure and high voltage gain in both Buck and Boost modes.
• Experimental validation demonstrated efficiencies of 93.5% (step-up) and 92.4% (step-down) for a 400W prototype.

Conclusions:

• The proposed tapped-inductor bidirectional Cuk converter effectively meets the demands for high efficiency and gain.
• The design offers a viable solution for energy storage system applications.
• Theoretical analysis was validated through experimental results.