|
Posted by azotic on August 15, 2008, 6:19 am
Please log in for more thread options
Just in case anyone is intrested, here are some pix of my 100 amp DIY VFD
being
assembled. As soon as time permits i will post a video of the VFD in
opperation.
I still have to make a remote control pannel.
http://members.cox.net/azotic/inv1.jpg
http://members.cox.net/azotic/inv2.jpg
http://members.cox.net/azotic/inv3.jpg
http://members.cox.net/azotic/inv4.jpg
http://members.cox.net/azotic/inv5.jpg
http://members.cox.net/azotic/inv6.jpg
http://members.cox.net/azotic/inv7.jpg
Best Regards
Tom.
|
|
Posted by Larry Jaques on August 15, 2008, 7:44 am
Please log in for more thread options
On Fri, 15 Aug 2008 03:19:17 -0700, with neither quill nor qualm,
>Just in case anyone is intrested, here are some pix of my 100 amp DIY VFD
>being
>assembled. As soon as time permits i will post a video of the VFD in
>opperation.
>I still have to make a remote control pannel.
>
>http://members.cox.net/azotic/inv1.jpg
>http://members.cox.net/azotic/inv2.jpg
>http://members.cox.net/azotic/inv3.jpg
>http://members.cox.net/azotic/inv4.jpg
>http://members.cox.net/azotic/inv5.jpg
>http://members.cox.net/azotic/inv6.jpg
>http://members.cox.net/azotic/inv7.jpg
Cool! It looks like the project is really coming together, Tom.
--
Challenges are gifts that force us to search for a new center of gravity.
Don't fight them. Just find a different way to stand.
-- Oprah Winfrey
|
|
Posted by Joseph Gwinn on August 15, 2008, 11:23 am
Please log in for more thread options
> On Fri, 15 Aug 2008 03:19:17 -0700, with neither quill nor qualm,
>
> >Just in case anyone is intrested, here are some pix of my 100 amp DIY VFD
> >being
> >assembled. As soon as time permits i will post a video of the VFD in
> >opperation.
> >I still have to make a remote control pannel.
> >
> >http://members.cox.net/azotic/inv1.jpg
> >http://members.cox.net/azotic/inv2.jpg
> >http://members.cox.net/azotic/inv3.jpg
> >http://members.cox.net/azotic/inv4.jpg
> >http://members.cox.net/azotic/inv5.jpg
> >http://members.cox.net/azotic/inv6.jpg
> >http://members.cox.net/azotic/inv7.jpg
>
> Cool! It looks like the project is really coming together, Tom.
The big power modules mounted on the heatsink - what are they and what
did they cost?
Thanks,
Joe Gwinn
|
|
Posted by azotic on August 15, 2008, 9:38 pm
Please log in for more thread options
>
>> On Fri, 15 Aug 2008 03:19:17 -0700, with neither quill nor qualm,
>>
>> >Just in case anyone is intrested, here are some pix of my 100 amp DIY
>> >VFD
>> >being
>> >assembled. As soon as time permits i will post a video of the VFD in
>> >opperation.
>> >I still have to make a remote control pannel.
>> >
>> >http://members.cox.net/azotic/inv1.jpg
>> >http://members.cox.net/azotic/inv2.jpg
>> >http://members.cox.net/azotic/inv3.jpg
>> >http://members.cox.net/azotic/inv4.jpg
>> >http://members.cox.net/azotic/inv5.jpg
>> >http://members.cox.net/azotic/inv6.jpg
>> >http://members.cox.net/azotic/inv7.jpg
>>
>> Cool! It looks like the project is really coming together, Tom.
>
> The big power modules mounted on the heatsink - what are they and what
> did they cost?
>
> Thanks,
>
> Joe Gwinn
>
They are dual IGBT transistors also known as a GTR module. Basicly
they are 2 NPN transistors conected in series to form a half bridge which
means the are capable of switching both + and - DC power back and forth.
You get AC output in the form of a square wave as a result. You can achive
the same result by using 2 individual IGBTs.
The GTRs i am using have the capacity to switch 100 amps at 1200 volts,
they have built in free wheeling diodes which cuts down on the component
count. I bought these GTRs on ebay for $8.00 each, shipping was $7.55.
Best Regards
Tom.
|
|
Posted by Joseph Gwinn on August 16, 2008, 5:14 pm
Please log in for more thread options
> >
> >> On Fri, 15 Aug 2008 03:19:17 -0700, with neither quill nor qualm,
> >>
> >> >Just in case anyone is intrested, here are some pix of my 100 amp DIY
> >> >VFD
> >> >being
> >> >assembled. As soon as time permits i will post a video of the VFD in
> >> >opperation.
> >> >I still have to make a remote control pannel.
> >> >
> >> >http://members.cox.net/azotic/inv1.jpg
> >> >http://members.cox.net/azotic/inv2.jpg
> >> >http://members.cox.net/azotic/inv3.jpg
> >> >http://members.cox.net/azotic/inv4.jpg
> >> >http://members.cox.net/azotic/inv5.jpg
> >> >http://members.cox.net/azotic/inv6.jpg
> >> >http://members.cox.net/azotic/inv7.jpg
> >>
> >> Cool! It looks like the project is really coming together, Tom.
> >
> > The big power modules mounted on the heatsink - what are they and what
> > did they cost?
> >
> > Thanks,
> >
> > Joe Gwinn
> >
>
> They are dual IGBT transistors also known as a GTR module. Basicly
> they are 2 NPN transistors conected in series to form a half bridge which
> means the are capable of switching both + and - DC power back and forth.
> You get AC output in the form of a square wave as a result. You can achive
> the same result by using 2 individual IGBTs.
>
> The GTRs i am using have the capacity to switch 100 amps at 1200 volts,
> they have built in free wheeling diodes which cuts down on the component
> count. I bought these GTRs on ebay for $8.00 each, shipping was $7.55.
So each module is a a half-bridge containing two IGBTs plus some
frewheeling diodes. What make and model?
The reason I ask is I'm designing a homebrew impulse magnetizer, to be
built around three 2900 microfarad 350 volt computer electrolytics I got
surplus somewhere (no longer recall when or where). In this case, the
current is all surge and no continuous, and the modules I'm considering
are Diode-SCR half-bridges. (IGBTs don't seem suitable.) The circuit
protects the electrolytics from reverse voltage by returning the
inductive kick to the capacitor with the correct polarity to charge it.
The surge current will be something like 3000 amps for 10 milliseconds.
I'm still working out the details, such as how big a surge current is
needed. Even if the SCRs and diodes are happy, the capacitors have a
limit as well.
I got the circuit idea from an expired US patent, 4,258,405 to
Steingroever. Steingroever uses Mercury-pool ignitrons, as nothing else
will withstand the currents necessary to use pulsed magnetic fields to
form metal. <http://en.wikipedia.org/wiki/Ignitron>
For more information on metalforming, see US patents 5,586,460;
5,684,341; 5,813,264; and 5,953,805. Also see the website of Dr
Steingroever's company: <http://www.magnet-physik.de/>.
They use very high voltages and small inductances, to yield very short
pulses, the better to create the eddy currents against which they push
to apply force to the metal being formed.
For our purposes, and with some care, the ignitrons may be replaced with
big SCRs. But even the biggest of SCRs is a wimp compared to a big
ignitron.
Richardson Electronics still offers ignitrons and hydrogen thyatrons:
<http://industrial.rell.com/et_ignitrons.asp>
<http://industrial.rell.com/et_Hthyratrons.asp>
But they tend to be expensive.
Joe Gwinn
|
| Similar Threads | Posted | | KE 100 update | August 1, 2006, 11:26 am |
| Re: Update | July 30, 2008, 2:04 am |
| PCB drills update | July 5, 2006, 6:23 pm |
| Bridgeport update & ??? | October 25, 2006, 8:10 pm |
| F/S Welders-update | November 19, 2006, 5:03 am |
| Trailer update | January 26, 2007, 7:49 pm |
| OT-Iraq update | January 31, 2007, 3:20 am |
| RR track update | February 6, 2007, 9:09 pm |
| JD-455 Transaxle update | September 4, 2007, 11:07 am |
| Van/truck update | November 4, 2007, 1:03 am |
|
|
Yahoo! 
Google 
Windows Live 
del.icio.us 
digg 
Netscape 
XML Sitemap
>being
>assembled. As soon as time permits i will post a video of the VFD in
>opperation.
>I still have to make a remote control pannel.
>
>http://members.cox.net/azotic/inv1.jpg
>http://members.cox.net/azotic/inv2.jpg
>http://members.cox.net/azotic/inv3.jpg
>http://members.cox.net/azotic/inv4.jpg
>http://members.cox.net/azotic/inv5.jpg
>http://members.cox.net/azotic/inv6.jpg
>http://members.cox.net/azotic/inv7.jpg