Optimizing the efficiency of a dc-dc boost converter over 98% by using commercial SiC transistors with switching frequencies from 100 kHz to 1MHz

In this paper an evaluation of Silicon Carbide (SiC) transistors currently available in the commercial market is presented. An experimental performance comparison between SiC JFET, Si MOSFET-SiC JFET cascode configuration and SiC MOSFET used as the main switch for a dc/dc boost converter (150 V/400 V) operating in Discontinuous Conduction Mode (DCM) is presented. The comparison of the different SiC devices is made in terms of the global boost-converter efficiency. Several experimental results dealing with the switching behavior of these SiC switches at different switching frequencies (from 100 kHz to 1 MHz) have been carried out in order to optimize the efficiency of the converter at different output power (300 W and 600 W). A good performance of all these switches is obtained from the point of view of the efficiency, highlighting the Si MOSFET-SiC JFET cascode behavior at 1MHz with an efficiency of 97.5% at 600 W. In addition, a possible application in the field of solar panels is proposed using the SiC JFET as the main switch. Continuous Conduction Mode (CCM) and DCM are tested at different switching frequencies with an output power of 1 kW and the results obtained are compared to the most widely reported in the bibliography.