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What is the actual reason behind IGBTs having lesser conduction losses than SiC MOSFETs? For the same application, I can see that an IGBT having the same power rating exhibits 10 times more switching losses but 3 times lesser conduction losses then SiC MOSFET.

JRE
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Alison
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    MOSFET have an on-resistance and IGBT have an on-voltage (to 0th order approximation). High currents favor the latter. – tobalt Jan 03 '23 at 13:32
  • For low current and/or low voltage, your first statement is not correct. – winny Jan 03 '23 at 13:37
  • could you please elaborate your point – Alison Jan 03 '23 at 13:52
  • Have you compared the on-state voltage for a (SiC) MOSFET to an IGBT over current? What were your findings? – winny Jan 03 '23 at 14:46
  • yes for 40A of ID/IC the onstate voltage drop for SiC is 3V while for IGBT it is 1.8V art recommended gate biasing voltage – Alison Jan 03 '23 at 15:02
  • Plot it over a wider range of current than just one value. What do you see? – winny Jan 03 '23 at 15:18
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    for IGBT 1.3V for 10A, 1.6V for 20A, 1.76V for 30A, 1.94V for 40A, 2.10V for 50A, 2.26V for 60A, 2.4V for 70A, – Alison Jan 03 '23 at 15:35
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    For SiC Mosfet 4.6V for 60A, 3.65V for 50A,2.81V for 40A, 2V for 30A, 1.31V for 20A ans 0.62V for 10A – Alison Jan 03 '23 at 15:37
  • @Alison I'm not sure what SiC mosfets and IGBTs you're comparing. Are you only comparing one of each or multiple? Can you provide part numbers? It will really depend on the application which is better. Every technology has their area where they out preform as well as areas where they are completely terrible. – bunker89320 Jan 03 '23 at 15:58
  • part number for IGBT is AFGHL40T120RHD and for Mosfet it is SCT070HU120G3AG. Its for 3 phase inverter controlling a PMSM motor – Alison Jan 03 '23 at 16:05
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    You have answered the question in your two comments. As you can see the constant(ish) voltage drop of the IGBT is less efficient at low current and more efficient at high current – tobalt Jan 03 '23 at 17:51

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