High Voltage Forum

Tesla coils => Dual Resonant Solid State Tesla coils => Topic started by: Laci on December 17, 2018, 09:36:03 PM

Title: TO-247 IGBT Comparison for High Frequency & Paralleled Operation
Post by: Laci on December 17, 2018, 09:36:03 PM
Hi,Guys!
I found some pretty nice IGBTs,but I'm not sure which ones are the best in a full bridge alone and paralelled for a high frequency coil(maybe QCW,250kHz-400kHz).

*FGH60N60
   180A peak,198W maximum power dissipation,0.33°C/W
   https://www.mouser.com/ds/2/149/FGH60N60UFD-889110.pdf


*FGA60N65
   180A peak,600W maximum power dissipation,0.25°C/W
   https://datasheet.octopart.com/FGA60N65SMD-Fairchild-Semiconductor-datasheet-68791176.pdf

*IRG4PC60U
   300A peak,520W maximum power dissipation,0.24°C/W
   http://www.irf.com/product-info/datasheets/data/irg4pc60u.pdf


The last one seems to be the best,but I never saw other coilers using it.Does anybody have experience with them,or knows other better IGBT?Any help would be greatly appreciated!
Title: Re: TO-247 IGBT Comparison for High Frequency & Paralleled Operation
Post by: Fumeaux on December 17, 2018, 10:22:31 PM
I can tell you as much as max amps isn't everything. Especially as you want a rather high frequency, rise and fall times matter a lot. The longer the switching needs, the more power gets turned into heat. I recommend you stick to what others have used, with similar coils/frequency. Look for something ward used or possibly if these aren't produced anymore, check loneoceans qcw-coils out. Choosing your own parts isn't as easy as one might think. There are many factors to consider and there is no shame in copying someone's design.

And if noone else used it, there is probably a reason behind it.
Title: Re: TO-247 IGBT Comparison for High Frequency & Paralleled Operation
Post by: sjsimmo on December 18, 2018, 03:18:05 AM
loneoceans used FGH60N65SMD (electrically equivalent to the FGA60N60SMD) in his QCW2 coil which had a resonant frequency of 308kHz. Note that the 'UFD' variety of FGH60N60 only has about half the power dissipation of the 'SMD' variety, so if you want to use a FGH60N60, I'd go for the SMD model, rather than the one you've listed.
Steve Ward also used the FGH60N60SMDs in his '"Fat Coil" QCW Tesla Coil', which had 8 H-bridges paralleled.  :)

I don't know of anyone (other than yourself) who has used IRG4PC60U in a DRSSTC or QCW coil. Looking at the datasheet, it seems that it's about twice as slow as the other two, so probably not as good a choice (looking at rise, fall, turn-on delay and turn-off delay times)... But I could be wrong ;). That said, it does have a higher peak current rating, which could be useful at lower frequencies.

I'm currently using the FGY75N60SMD in my DRSSTC, but I haven't pushed them very hard yet, so I don't know their limits. They're slightly slower than FGH60N60SMD, but still faster than IRG4PC60U, and are rated for 225A peak.
Title: Re: TO-247 IGBT Comparison for High Frequency & Paralleled Operation
Post by: Laci on December 18, 2018, 09:25:26 PM
Thanks for the advices!
Sadly the store went on vacation and I can't order the parts until 20 January :( .I will try to run dual resonant with my current HGTG30N60A4D full bridge,but just carefully not to destroy them(under 250Ap)after I repair my oneTesla interrupter's SD card function,which isn't working.Another interesting experiment would be a IRFP460 bridge ramped,maybe buck modulated with high primary impedance to keep peak currents low.I will try that out with my small coils!
Title: Re: TO-247 IGBT Comparison for High Frequency & Paralleled Operation
Post by: Mads Barnkob on December 18, 2018, 09:42:25 PM
Thanks for the advices!
Sadly the store went on vacation and I can't order the parts until 20 January :( .I will try to run dual resonant with my current HGTG30N60A4D full bridge,but just carefully not to destroy them(under 250Ap)after I repair my oneTesla interrupter's SD card function,which isn't working.Another interesting experiment would be a IRFP460 bridge ramped,maybe buck modulated with high primary impedance to keep peak currents low.I will try that out with my small coils!

Just get the calculator out as sjsimmo did in his thread and you know all about those IGBTs :)

On a side-note, I had a onetesla midi interrupter returned to them because of malfunctioning sd card reader, it needed resoldering/reflow, whatever, it had bad connection and sd card would not stay in. I did not get a new unit but a repaired board back, which was not done very nicely :(
Title: Re: TO-247 IGBT Comparison for High Frequency & Paralleled Operation
Post by: Laci on December 18, 2018, 10:30:34 PM
I built the interrupter myself :D It uses a microSD SPI module,but the LCD screen glitches when I accidently touch it's metal screws while the coil is working.I hope the microSD module hasn't died, although the screen displays "No card found" everytime.The interrupter is already a big mess,so it'll be hard to desolder it I guess...