Single Switch Ultra-High Step-Up Quadratic Converter With Low Input Current Ripple

This article proposes a single switch ultra-high step-up converter based on the quadratic structure. In this converter, an auxiliary circuit is integrated with the quadratic topology which uses coupled inductors and switched capacitors to improve the voltage gain and switch voltage stress without adding any extra magnetic core. The auxiliary circuit elements are arranged so that a passive clamp path is created to absorb the leakage inductance energy and recycle it to the output. In addition, most diodes turn off at zero current which eliminates the reverse recovery problem. Also, due to low switch voltage stress, high-quality switch with low conduction loss is used leading to high converter efficiency. The presented converter benefits from continuous input current and common ground between input and output which increase its applicability. The proposed converter is completely analyzed and compared with other counterpart structures. The implemented 300 W laboratory prototype converter has achieved the peak efficiency of 96%.