Simulation studies of half-bridge isolated DC/DC boost converter

In order to utilize energy from low voltage power source it is necessary to use isolated DC/DC boost converter which will provide desirable input voltage step-up. To obtain a high voltage gain it is necessary to apply a magnetic device with the relevant turns ratio to the converter structure. This can be coupled inductor or transformer. The great advantage of the transformer is galvanic isolation between the subsequent power levels. Unfortunately, the high values of voltage gain is accompanied by significant currents on the primary transformer side. Large DC input currents cause an increase in power losses as the transistor conduction losses are proportional to square of current. The solution to this problem would be to divide a large input current into smaller currents through applying balancing transformers in converter structure. The input current in one stage exactly matches the current in the parallel branch, therefore there is no need for additional control to guarantee current balancing between power stages. This technique, together with the use of transistors with a small drain-source resistance and output SiC (silicon carbide) Schottky diodes enables converter to achieve necessary output voltage. This paper presents PSpice simulation results and mathematical analysis of half-bridge isolated DC/DC boost converter. In presented circuit high voltage gain and high conversion efficiency were achieved.