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CAB011M12FM3 SpeedFit switching loss predictions

Matt
Matt Contributor Level 2
edited August 2023 in Module Products

I have been using the excellent SpeedFit simulation tool to assess the most suitable module rating for a DC/AC inverter application. I am a little confused by the results for the CAB011M12FM3 device...maybe the model has been adjusted recently?

Predicted switching losses for the CAB011M12FM3 device are higher than the smaller CAB016M12FM3 device (as expected), but confusingly also higher than the larger CAB008M12GM3. The switching losses for the CAB011M12FM3 seem to have increased from results obtained earlier in the year (was circa 365W in April, now 525W under the same conditions).

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Comments

  • Forum_Moderator
    Forum_Moderator Wolfspeed Employee - Contributor Level 4

    Thank you for your post, it has been approved and we will respond as soon as possible.

  • BlakeNelson
    BlakeNelson Wolfspeed Employee - Contributor Level 2

    Hi Matt,

    I have reviewed our CAB011M12FM3 PLECS model and, as you pointed out, the losses have indeed increased. Further investigation revealed that when we updated our Wolfpack thermal values in April to match the latest datasheets, the new version of the PLECS model had an erroneous switching energy model. The new model has higher switching losses, but it also less accurately models the datasheet.

    I have made new versions of the model which roll back to the prior switching energies but keeps the latest thermal value. I've attached the model, but it will take a few days to get the new model onto SpeedFit. I'll let you know as soon the new model is available on SpeedFit.

    CAB011M12FM3.xml

    Thank you for your valuable feedback. My team is reviewing our internal validation procedures to try to prevent such mistakes making it out in the future.

    Sorry for the inconvenience this has caused and I hope you continue to rely on SpeedFit going forward.

    Thanks,

    Blake

  • Matt
    Matt Contributor Level 2

    Blake,

    Thanks for looking into this and finding the issue, and very well explained.

    Best regards

    Matt

  • BlakeNelson
    BlakeNelson Wolfspeed Employee - Contributor Level 2

    Hi Matt,

    I wanted to follow up and let you know that the model on SpeedFit has been updated.

    Please don't hesitate to reach out if you have any further questions!

    Thanks,

    Blake

This discussion has been closed.