How are losses calculated when IGBT is operating at voltage higher than mentioned in datasheet

Question

In the three phase grid connected inverter model for thermal modelling,the IGBT in chopper circuit sees a voltage of more than 700V. However in the datasheet included in the model the turn on losses are written only till 600V. How are losses determined for higher voltages

Answer 1

Hello,

You point out an important detail, yes, the boost converter devices in that model are probably a little undersized with the default PV array sizing and related power output. You could of course stack two in series for the 800V setup and modify the modulation signals to accommodate that. But to answer your question, linear extrapolation is used to determine losses for any voltage, current, or temperature inputs that fall outside the loss table limits, using the two nearest datapoints.

Regards,

Kris

Comments

Thank you Kris