Dear Milan
Your approach is correct in principle, so there is likely a mistake somewhere in the implementation.
Since PLECS 5.0, this kind of paralleling is supported natively through the Number of parallel devices parameter, but only for MOSFETs, diodes, and MOSFET with diode components. For IGBTs, this is less common and still needs to be handled manually.
In PLECS 4.9 and earlier, paralleling had to be implemented in the initialization script. Although the example below is for MOSFETs, the same idea can be adapted for IGBTs:
thermal_parallel_example.plecs (35.6 KB)
C3M0065100K.xml (10.7 KB)