LDU inverter gate drive PCB fault finding  [SOLVED]

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Boxster EV
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LDU inverter gate drive PCB fault finding

Post by Boxster EV »

I’m playing with one of these on the bench out of a spare inverter. Does anyone have any specs or guidance on fault finding them?
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Re: LDU inverter gate drive PCB fault finding

Post by fredd90 »

Hello

When I repaired the three pcbs, i digged deep In the manual to the igbt controller pdf.

https://www.mouser.se/ProductDetail/726-1ED020I12FA2XUM

I traced down fault at the igbt and transistors/mosfets.
And resistors/diodes between igbt controller and transistors/mosfet.

A litte error will be fatal because that you have 400vdc in to that little pcb.
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Re: LDU inverter gate drive PCB fault finding

Post by Boxster EV »

Thanks, the spec sheet is helpful. I’ll start playing.
Infineon-1ED020I12FA2-DS-v03_00-EN-1225902.pdf
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Not sure I’ve got the cajonas to desolder the whole PCB and replace everything en masse like you did.
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Re: LDU inverter gate drive PCB fault finding

Post by Boxster EV »

fredd90 wrote: Fri Jun 03, 2022 11:22 am
A litte error will be fatal because that you have 400vdc in to that little pcb.

Your’re not wrong - IGBT driver is fried. The part is currently out of stock. 🤨

0C3C4D88-5760-474A-93BA-2E9D1B8808AB.jpeg
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Re: LDU inverter gate drive PCB fault finding

Post by Boxster EV »

I don’t know why this IGBT driver fried itself, but I managed to repair the board by transferring a second-hand semiconductor over from a parts bin inverter section courtesy of Damien – in fact this is the second LDU that’s been successfully repaired using these scrap parts.

Very important that the lacquer type material that covers the component needs to be removed by warming it up before de-soldering - used a hot air solder station for the removal process and was very careful not to damage the PCB with too much heat.

Upon powering up the inverter, the red fault LED is no longer illuminated and the inverter now goes into run mode without an overcurrent error.
9D825808-BAA2-4E96-AF99-623581871673.jpeg
CE2AF097-FF48-41EF-B05F-BBF4B626DCD3.jpeg
217C038C-5E25-4880-A6C1-BBE4E5D3B987.jpeg

FDBA0B7B-31D3-491A-B7CE-844BC340BB82.jpeg
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Re: LDU inverter gate drive PCB fault finding  [SOLVED]

Post by Boxster EV »

Made a quick beginner’s guide video whilst doing a bench test.

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Re: LDU inverter gate drive PCB fault finding

Post by jon volk »

Nice save!
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Re: LDU inverter gate drive PCB fault finding

Post by Boxster EV »

jon volk wrote: Wed Jun 22, 2022 2:21 amNice save!
Think the parts originally came from you. Thanks!
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