Practical implementation of a silicon carbide-based 300 kHz, 1.2 kW hard-switching boost-converter and comparative thermal performance evaluation

Field experience shows that the vast majority of solar photovoltaic (PV) energy system failures are related to the power conditioning system (PCS). Among the principal reliability issues of PV PCSs are thermal management and heat extraction mechanisms. The study considers practical implementation of a DC-DC boost converter as a solar PV pre-regulator in terms of thermal management, with comparative thermal performance evaluations of silicon carbide (SiC) semiconductors and silicon (Si) metal-oxide-semiconductor field-effect transistors (MOSFETs). Thermal performance evaluation of power semiconductors is based on a 1.2 kW DC-DC converter with: (i) various switching frequencies up to 300 kHz, in steps of 25 kHz; (ii) case temperatures from 25 to 150°C; and (iii) a natural convection heatsink with temperature increase rate of 0.5°C/W. Simulation and experimental results verify that losses from SiC semiconductors are low compared with Si MOSFETs. This provides an opportunity for designing a pre-regulator DC-DC boost converter with less effort required for thermal management and enhanced reliability.