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CO2 Power Supply Schematic Help

DashApple

DashApple

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upaa27 said:
First off thank you guys so much for putting up with my noobishness and it is really great to have some teachers even if on a forum. :)


Ok so basically stick the 10kv diodes in series to triple their rating
Click to expand...

Yup , the diodes are all ready made from multiple series diodes inside the one package , series 3 "diodes" will give you a 30Kv diode .

It's Easyer to string lower voltage diodes together , I did the same thing with 600v diodes on my 2Kv transformer
 
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The Lightning Stalker

The Lightning Stalker

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upaa27 said:
For the capacitor, can't exactly find many good priced capacitors in the nf range rated for 30kv. Would making my own work and be efficient enough?
Click to expand...

That is the problem with doing it the
"easy" way. With mains frequencies, you
need big expensive capacitors. Just be
thankful you live in an area with 60Hz
mains. Most of the world uses 50Hz, making
the problem even worse. You could get 2
sets of these and parallel them to get
enough capacitance.

015 uf 30000 WVDC Capacitors 15nF 30KV High Voltage Quantity 9 | eBay

Or keep looking. Or you could make your
own. With 2mm thick glass, it would only
take about 15x15cm area to get to 100nF,
though it would depend on the glass.
 
Sigurthr

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^ Which is why it is a LOT easier to use a HF drive and a flyback style transformer. Either standard DC, or a custom/DIY AC one followed by a cascade multiplier. Either way you need to smooth the DC pulses, and the capacitance value at 60KHz is much easier to achieve.
 
upaa27

upaa27

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Sigurthr said:
^ Which is why it is a LOT easier to use a HF drive and a flyback style transformer. Either standard DC, or a custom/DIY AC one followed by a cascade multiplier. Either way you need to smooth the DC pulses, and the capacitance value at 60KHz is much easier to achieve.
Click to expand...

Wouldn't the caps smooth the output?
 
The Lightning Stalker

The Lightning Stalker

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upaa27 said:
Wouldn't the caps smooth the output?
Click to expand...

Yeah, he's just saying that at higher
frequencies, the caps can be smaller
because the pulses occur more often keeping
the voltage on the caps topped off. Using
Sigurthur's example, at 60kHz you could get
away with even 500pF caps without a problem.
 
upaa27

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I think I will use wax paper and aluminum foil (5 meters) for around 6.5uf while still being able to take the voltage load then rol it up.

Will this work without jumping plates?
 
Sigurthr

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You have to make the plates smaller than the dielectric so that the cap won't arc over. You also have to place the lead-ins away from each other.

Do watch for dielectric heating and corona. It'l take out a cap quickly.
 
upaa27

upaa27

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Sigurthr said:
You have to make the plates smaller than the dielectric so that the cap won't arc over. You also have to place the lead-ins away from each other.

Do watch for dielectric heating and corona. It'l take out a cap quickly.
Click to expand...

Will do. I might go with glass and aluminum plates now due to the fact that they will be easier to set up and should be more resilient to corona. To bad that they will be big
 
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Sigurthr

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Glass works excellently. When I did a DIY plate cap I used glass and heavy duty aluminium foil. It's just heavy, expensive, and fragile. I tried PP too, but it eventually failed from dielectric heating.
 
upaa27

upaa27

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Sigurthr said:
Glass works excellently. When I did a DIY plate cap I used glass and heavy duty aluminium foil. It's just heavy, expensive, and fragile. I tried PP too, but it eventually failed from dielectric heating.
Click to expand...

How would an electrolytic cap work? I would basically soak paper towels in baking soda water, put plates on either side, roll and put into a jar full of the baking soda water.

Would that be able to take the voltage load without using a ridiculous amount of aluminum foil?

Only thing that I can see that might go wrong is the polarity might interfere with the circuit
 
Sigurthr

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The problem is the varying levels of moisture in the electrolyte and induced electrolyte breakdown and hydrolysis. Just stick with a dry cap.
 
Cyparagon

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Also, electrolytics aren't even commercially available much higher than 500V, so there's no way in hell you're going to DIY a 20kV one. I'd just buy a pair if I were you... or omit them entirely.
 
upaa27

upaa27

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I might just go with the zvs flyback circuit as it is a lot easier to hook up(not using massive cables) and is much smaller than making huge caps. Only problem is the fbt as It looks a bit harder to acquire.

Pump the flyback into the nst then voltage double it using the 2200pf caps
 
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