New coupled-inductor SEPIC converter with very high conversion ratio and reduced voltage stress on the switches

The new circuit of the coupled-inductor SEPIC converter is proposed. By addition of the secondary output inductor and diode in a basic SEPIC converter a new converter with a large conversion ratio is obtained. The splitting of this secondary inductor into two windings reduces the voltage stresses on the main switch and diodes. The additional diode helps to circulate the leakage inductance energy to the load in a non-oscillatory manner. The transistor turns on/off with soft- switching. The voltage stress on both the transistor and diodes is less than the output voltage. Computer simulation and experimental results confirmed the theoretical expectations.