I am simulating a non-ideal IGBT using passive elements and controled current sources. In one of the current sources I use If-then-else statements.The switching frequency that I am using is 3000 Hz. For a solution time step of 1.666667 us or bigger the results of the simulation are what I was expecting, but when I try to use a time step lower than this value (for example 0.833333 us) I start having convergence issues. I am using the same value for the solution time step and the plot step. I need smaller solution time steps so I can get a better view of the system behaviour.
I don't understand what could be happening and what I could do to resolve this problem.
For a time step of 1.666667 us this is the collector current and collector-emitter voltage of the IGBT:
And for a time step of 0.833333 us this is the collector current and collector-emitter voltage of the IGBT:
Do you have any idea of what could be happening?