A new quadratic boost converter featuring an integrated coupled inductor and low input-current ripple for renewable energy sources

This paper presents an ultra–high step-up quadratic DC–DC converter that achieves a high voltage gain while maintaining relatively low voltage stress on semiconductor devices and a common ground between the input and output, which is attractive for practical high-voltage, low-power-stage applications. The proposed topology uses a low part count and shapes the source current with a low input-current ripple, easing EMI filtering. By properly routing the magnetizing energy, the converter inherently absorbs the leakage inductance energy and eliminates switch voltage spikes and no dissipative clamp is required. The diodes commutate with zero-current switching (ZCS) at turn-off, thereby mitigating reverse-recovery losses and contributing to improved efficiency. A complete steady-state analysis in CCM/DCM is provided, including a closed-form high-gain expression. A 200 W laboratory prototype was built to validate the analysis; measurements confirm the predicted high gain, low stresses, and low input ripple, and demonstrate a 92% efficiency at full load. • An ultra-high step-up non-isolated quadratic DC–DC converter with common ground is proposed. • High voltage gain is achieved without extreme duty cycles or auxiliary clamp circuits. • Reduced semiconductor voltage stress and ZCS turn-off of diodes improve efficiency and reliability. • A simple single-duty-cycle control strategy ensures stable operation and fast dynamic response. • Experimental results from a 200 W prototype validate high efficiency and practical suitability for renewable-energy applications