# Big IGBT question



## frodus (Apr 12, 2008)

link to the datasheet might help


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## Georgia Tech (Dec 5, 2008)

http://www.infineon.com/dgdl/fz2400...601e3&fileId=db3a304412b407950112b43041434fd2

OR

http://www.infineon.com/cms/en/product/channel.html

Click the FZ2400R17KF6C B2


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## Tesseract (Sep 27, 2008)

Georgia Tech said:


> *FZ2400R17KF6C B2* ..what would be the pratical maximum current you would push through this thing? 1000 amps? or what??


If you can get rid of the heat you can run damn near whatever current you want through it. Datasheets for parts at this power level typically do not "stretch the truth" as is common with lower power discretes.

Add up the thermal resistances from junction to case to heat sink, multiply by the estimated watts dissipated, and as long as the temp at the junction is less than 125C you are golden.

You will, of course, need to use a liquid cooled heat sink for this application as dissipating 7kW or so of heat over an area of 266cm^2 is well beyond the capability of forced convection.


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## Georgia Tech (Dec 5, 2008)

Tesseract said:


> If you can get rid of the heat you can run damn near whatever current you want through it. Datasheets for parts at this power level typically do not "stretch the truth" as is common with lower power discretes.
> 
> Add up the thermal resistances from junction to case to heat sink, multiply by the estimated watts dissipated, and as long as the temp at the junction is less than 125C you are golden.
> 
> You will, of course, need to use a liquid cooled heat sink for this application as dissipating 7kW or so of heat over an area of 266cm^2 is well beyond the capability of forced convection.


Thank you BUD!!!


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## jamesweirick5 (Jul 26, 2007)

Georgia Tech said:


> Thank you BUD!!!


So how did your 2400A IGBT work out. If so, where do I get some?


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## subcooledheatpump (Mar 5, 2012)

Depending on what voltage you'd be using, you might actually need a stepped turn off. Becausde of such high currents, a regular "flat" turn off might cause such a high voltage spike, the IGBT could be destroyed. 

Though I take it you won't be using 1.7 kV


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## Siwastaja (Aug 1, 2012)

subcooledheatpump said:


> Depending on what voltage you'd be using, you might actually need a stepped turn off. Becausde of such high currents, a regular "flat" turn off might cause such a high voltage spike, the IGBT could be destroyed.
> 
> Though I take it you won't be using 1.7 kV


With IGBT that big, you won't have too fast turn-off accidentally... To do that, you need to design a HUGE gate driver. Well you need to do it anyway if you don't want to kill the IGBT (or at least cause huge losses) by desaturating it for a relatively long time.

So, just limit the gate current to some practical value. For IGBT that big, it will be in the range of 10-50A anyway. Make a 20A driver and use 1...2 ohm turn-off gate resistor and the turn-off won't be too quick. You can start with higher gate resistance and carefully monitor the voltage spikes and then increase the drive current to reduce losses.

A good, low-inductance bypass capacitor (probably in the range of 1...10 µF) mounted directly to the DC bus at the IGBT is a must, too.

And keep the battery voltage below 1000V and you'll have some leeway in the voltage rating for the spikes... But if it is just one IGBT I guess this is for a DC controller so probably the battery voltage won't be that high anyway. (OTOH, someone _might_ design a >1000V controller for using an unmodified industrial AC induction motor.)

(I notice that the topic is old, but hopefully this might help others.)


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## subcooledheatpump (Mar 5, 2012)

I'd like to be able to try something like that, 1 kV+ inverter. Like what they use in electric locomotives. Totally impractical, I know but I'd still like to try


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## jamesweirick5 (Jul 26, 2007)

Siwastaja said:


> With IGBT that big, you won't have too fast turn-off accidentally... To do that, you need to design a HUGE gate driver. Well you need to do it anyway if you don't want to kill the IGBT (or at least cause huge losses) by desaturating it for a relatively long time.
> 
> So, just limit the gate current to some practical value. For IGBT that big, it will be in the range of 10-50A anyway. Make a 20A driver and use 1...2 ohm turn-off gate resistor and the turn-off won't be too quick. You can start with higher gate resistance and carefully monitor the voltage spikes and then increase the drive current to reduce losses.
> 
> ...


Sounds doable but tricky, but where do I get affordable IGBTs?


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## shortbus (Sep 27, 2011)

jamesweirick5 said:


> Sounds doable but tricky, but where do I get affordable IGBTs?


I've bought 10 of various voltage and amp ratings from a couple of guys that sell on Ebay. They are take outs from surplus equipment, but so far all have been good working components. At $20 - $50 each for $500 IGBTs its worth using them to experiment/prototype with. Or even use in a finished DIY project.

I'll get a link if anyone is interested. The also sell snubber caps, big heatsinks, and other related stuff at great prices. Not connected with them at all, just a happy customer.


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## PStechPaul (May 1, 2012)

I've had good experience with http://stores.ebay.com/lisa-ctrsurplus

IGBTs, link capacitors, heat sinks, contactors, complete drives, etc.


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## subcooledheatpump (Mar 5, 2012)

Do a google search "CTR Surplus Ebay Auctions"

CTR surplus has tons of IGBTs, lisa-ctrsurplus is just one of their ebay stores, they have other ebay stores with more.

They actually had a 1500 lb crate full of assorted IGBTs


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## shortbus (Sep 27, 2011)

PStechPaul said:


> I've had good experience with http://stores.ebay.com/lisa-ctrsurplus
> 
> IGBTs, link capacitors, heat sinks, contactors, complete drives, etc.


Those are the guy's! There are I think four people selling from ctrsurplus. If you buy more than one item, try an offer to them, their real good at dropping prices.


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## hbthink (Dec 21, 2010)

I have numerous brand new in packaging Semikron modules

SKiM 606GD066HD

these are intended for vehicle use and have major advances to increase reliability in transportation uses like sintered silver connections not soldered.

See

http://www.semikron.com/skcompub/ko/SKiM.pdf

They were purchased from Azure Dynamics and intended for the DMOC845 heavy duty controller. I also have mounted driver boards for these that are already tested and conformal coated. When I finish inventory I will post with prices and photos.

Steve


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