High Step-Up SEPIC-Based Trans-Inverse DC–DC Converter With Quasi-Resonance Operation for Renewable Energy Applications

This article proposes a new single switch trans-inverse high step-up converter applicable in sustainable sources of energies such as photovoltaic (PV) and fuel cell (FC). Through developing a single-ended primary-inductor converter by a three-winding built-in transformer (BIT) mixed with a switched-capacitor voltage multiplier cell, high voltage gains as well as low voltage stress across the mosfet can be achieved to reduce the required duty cycle and the conduction losses. The third winding of the BIT acts in a trans-inverse manner whose turns ratio should be lower than unity. Hence, with a lower number of windings the voltage gain can also be improved. Furthermore, the quasi-resonance operation of the proposed converter, reduces the associated switching losses of the mosfet and also guarantees zero current switching of diodes through the whole switching cycle. Meanwhile, low input current of the proposed converter serves as an interesting feature to maintain PV and FC lifetime. The detailed steady-state analysis of the proposed high-efficiency converter is presented with an extensive performance comparison to explore its advantages. Finally, a 200-W prototype with 20–250-V voltage conversion is developed in the laboratory to examine the carried steady-state analysis.