A nonisolated interleaved boost converter for high-voltage gain applications

The requirement for high-voltage gain step-up dc-dc converters is increasingly becoming important in many modern power supply applications. They are an essential power conversion stage in systems, such as grid-connected renewables and electric vehicles. Unfortunately, achieving a low cost, high efficiency, power dense, step-up converter with high-voltage gain is not a trivial task; yet they are highly desirable when aiming for a green power supply solution. For this reason, this paper presents a new nonisolated interleaved dc-dc boost converter with zero voltage switching. The proposed converter is designed around a coupled inductor with an active-clamping circuit arrangement to recycle the coupled inductor leakage energy and reduce the voltage stress on the semiconductor devices. The lack of isolation transformer improves the power density of the system. Likewise, the interleaved circuit allows for high efficiency over a broad range of operating conditions. The theoretical behavior of the power converter is fully described, and the performance of the circuit is validated through experimental results. Importantly, the circuit is capable of achieving > 10 × voltage gains without the need to apply extreme modulation signals to the pulse width modulation circuit.