Thank you for your great question! PLECS does not automatically feed back the thermal losses into the electrical domain at this time. It is possible to implement a temperature-dependent Ron for a MOSFET in PLECS, however, by using the Variable Resistor component in series. Note that a variable resistance inherently creates an algebraic loop, but as of a recent version of PLECS, it is possible to solve this situation.
Attached is an example model of a buck converter where a SiC MOSFET (E3M0280090D) from Wolfspeed is used. The datasheet and PLECS thermal description file are found here: https://www.wolfspeed.com/power/products/sic-mosfets/e3m0280090d
. The datasheet has, for example, two plots (Figure 4. and Figure 5.) that can be used to develop a characteristic for the Junction Temperature vs. Ron behavior. Using this information, a basic dataset of Ron values at several operating temperatures and using a fixed Ids current of ~7A, has been captured using a lookup table in the included model.
Hopefully this example demonstrates the concept and can be used as a reference for you to create a higher resolution temperature dependency for your application. Please let us know if you have any questions.