Error "Derived parameter initialization for Vbe_sat failed to converge"

Hi there,

I'm trying to model an IGBT using the N-Channel IGBT block (simscape electrical library), but I obtained the above mentioned error. From what I've observed it seems that the error is related to the value that I introduced in the "Collector current at which VCE(sat) is defined" parameter where I put 1.000A (same value as in the datasheet).

I'm using the Full I-V and capacitance characteristics variant and concretely equivalent circuit based on a PNP bipolar transistor and N-channel MOSFET mode.

These are the values that I've introduced in the main tab:

Ices: 10mA

Voltage at which Ices is defined: 1700V

Vge(th): 6.5V

Vce(sat): 2.15V

Collector current at which Vce(sat) is defined: 1000A

Gate-emitter voltage at which Vce(sat) is defined: 15V

Temperature: 150

https://es.mathworks.com/help/physmod/sps/ref/nchanneligbt.html#brj69we-3

Is there someone who knows how to solve the error?

Thank you in advance,

Ander.

Answer 1

[Joel Van Sickel]

Hello Ander,

the issue is that RC and RE need to be lower to calculate a realistic Vbe-sat. I believe it needs to be lower than Vce. To do this, lower the values in the advanced tap of RC and RE. I tried lowering them both by a factor of 100 and was able to get it to work.

Regards,

Joel