SCR to Discharge Capacitor Bank

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jct891

Joined Sep 30, 2016
9
I survived!:)

I was in a 7 (seven) Tesla MRI, 2 years ago. It's survivable, but it gets really hot in there!
You can feel the energy pulses heating your skin.:confused::eek:

So far, the only information we have is 52uH, 400V and 7334 uf's.
Working with nothing but that results in huge numbers and a similar amount of doubt.
Repeating myself: The resistance of the wire is going to be a limiting factor.
You can't slam mega-amps around in the basement like a battleship mounted rail gun.
There's a lot more to this than a capacitance, some microhenries, and a switch, and those other parts will set the limits.
Provide that information to get useful answers.
@#12 and @BertHickman I have attached some pictures, I have attached my coil for demonstrations purposes only, I know it still needs to have a trigger circuit in between. The resitance of my coil is 0.2 Ohms, it has 15 turns, a radius of 45mm and a lenght of 25mm. I'm trying to accomplish what is on this link http://www.bem.fi/book/22/22.htm. However I had 400V caps and not 500V so I calculated the energy produced by the circuit on the link and did the math to produce the same amount of energy with 400V caps. The only thing I got left is the thyristor trigger circuit. I hope this helps, thanks for all your help!
IMG_20161003_214017933.jpgIMG_20161003_214039949.jpgIMG_20161003_214010207.jpgIMG_20161003_213758774.jpgIMG_20161003_214017933.jpgIMG_20161003_214039949.jpgIMG_20161003_214010207.jpgIMG_20161003_213758774.jpg
 

tcmtech

Joined Nov 4, 2013
2,867
My rough estimate says that given the estimated resistances of the wiring you have in your pictures plus the likely fairly high ESR values those type of electrolytic would have I would likely put your peak discharge below the 1 KA range at best. :oops:

Now if those capacitors were mounted on two solid copper buss bars of say 1" x .25" feeding to your SCR then through your coil but made of 4 Ga or heavier wire you may be able to hit the 1 - 2 thousand amp pulse range if the capacitor ESR was still not too high.

BTW, if you want HV capacitors with very low ESR values common power factor/motor run capacitors are a good choice being even a large 500 VAC 100 uF rated one the size of a pop can can run on a a 480 VAC circuit conducting a pretty impressive 26.5 amps without getting the slightest bit warm whereas even if your 400 volt 100 uF electrolytic were non polar types were subjected to that current level they would blow themselves to bits in a few seconds.

They would cost you more but if the circuit was built to handle the high amps I think that 7400 uF of those would not have a problem producing a multi KA pulse.
 

DickCappels

Joined Aug 21, 2008
10,662
Interesting discussion but it is likely that it violates the User Agreement. This thread is losed for discussion while it is being evaluated.
 
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