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I conducted a double pulse test (DPT) on an AUIRFP4568 MOSFET in the lab as well as in LTspice. With the same setup as used in the lab I created a setup in LTspice using the SPICE model of the MOSFET. The behaviour I am getting in terms of switching energies is completely different. I am unable to understand why.

For example, in the lab Eon is very much smaller than Eoff but in LTspice Eoff is much smaller than Eon. Ereq is also roughly 50% different from the measured value. I use the same pulse length, the same load inductor value, the same value of Rgon, Rgoff, RG, and CG, and the same input capacitor bank for the 24 V switching voltage with switching currents varying from 10 A to 60 A.

I don't know why we don't have any sort of correlation between simulated and measured values. I don't know what I should do now.

Can anyone explain what the reason could be?

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    \$\begingroup\$ Simulator != reality, basic truth of simulators. Does the model accurately represent the MOSFET? Do the simulated passive components truly represent the passive components? Have you considered parasitic effects in the wiring (capacitance, inductance, and resistance in wires?) \$\endgroup\$
    – JRE
    Commented Jan 24, 2023 at 13:17
  • \$\begingroup\$ @JRE Yes the Model i am using for MOSFET is the model provided by infenion. I have also included parasatics values for driver loop, power loop and source inductance but still its kind of weird to have that much deviation in measured and calculated values \$\endgroup\$
    – Alison
    Commented Jan 24, 2023 at 13:30
  • \$\begingroup\$ Test bed parasitics it looks like to me. \$\endgroup\$
    – Andy aka
    Commented Jan 24, 2023 at 13:45

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