Why SiC MOSFET Might Be Better Than IGBT

 

The use of SiC MOSFETs in electronic devices is rapidly increasing. Whereas many experts say the reason for this rise is simply because SiC technology has finally matured and offers a performance better than that of IGBTs. Others believe there are significant reasons.

 

Sic MOSFET vs. IGBT

 

One factor commonly acknowledged among experts is that SiC MOSFETs have a lower body diode voltage drop than IGBTs. This allows for a 20% improvement in conversion efficiency (from AC to DC) as well as higher power density and cooler operation, all of which contribute to the rise of silicon carbide MOSFETs.

 

IGBTs are utilized where well-controlled, medium-speed switching is required, and they can be less expensive than equivalent silicon MOSFETs. Furthermore, while IGBTs can take higher voltages than typical MOSFETs, they have large switching losses when silicon is employed. 

 

These losses generate heat, necessitating the use of costly and massive thermal management solutions as well as limiting the efficiency of power-conversion systems.

 

Silicon carbide MOSFETs have good thermal conductivity, allowing for lower switching losses. Reduced switching losses (even at high voltages) alone result in significantly less heat generation, lowering the thermal management needs of systems using silicon carbide MOSFETs rather than silicon IGBTs.

 

This results in lower total expenses as well as a far more compact, weight-saving design. Furthermore,  silicon carbide mosfets are more robust than silicon IGBTs, which make them perfect for applications in harsh environments that IGBTs would struggle with, such as onboard chargers for solar power systems and electric vehicles.

 

Takeaway

 

In conclusion, experts say silicon carbide mosfets are better in applications where high efficiency and high operating frequency are critical.  These applications, like EV charging, are able to reduce their system size and costs when switching the  silicon carbide mosfets at high frequency. With these benefits, designers will be motivated to move from IGBT to the more expensive silicon carbide MOSFETs, marketing the new technology adoption and efficiency performance enhancement.

 

On the other hand, IGBT is still the mainstream, matured and cost effective solution for the lower frequency application like motor drive and AC inverters.