A single-switch high step-up DC-DC converter with coupled inductor

With the development of photovoltaic (PV), fuel cells and uninterruptible power supply (UPS), high step-up converter plays an important role in them. In this paper, a single switch high step-up DC-DC converter is proposed, which can achieve high voltage gain without extreme duty cycle and huge turn ratios of coupled inductor. The leakage energy of coupled inductor can be recycled and the voltage across the switch can be clamped. Moreover, the reverse recovery of some diodes can be reduced. All these characteristics make it possible to design appropriate parameters to realize high step-up gain and high efficiency. The operating mode, static analysis and simulation results have been presented, and a prototype circuit has been realized to verify the effectiveness of the proposed converter.