High Voltage (600VDC)

[Krumlink]

I am currently working on a coilgun and I have generated a 600:mu:f Capacitor bank at 600V, giving me 108 Joules of energy. I now need to generate that 600VDC. I have been looking online on how to generate the 600VDC, but to no avail. I have worked on High Voltage and Coil Guns before, but I require this high voltage source. I would like to use a small transformer with a high frequency, so I can save on space. I just have to find directions on how to wind a transformer. Any good websites?

 

[ericgibbs]

hi,
There are voltage doublers and triplers that will give you a few hundred volts.
You could use a bog standard mains transformer, driven by a simple switcher.

Stating the obvious, that level of charge can kill, I know you are aware of that, but ensure that no other less experienced person finds out the hard way.

 

[Leftyretro]

Why don't you contact these guys, they seem to be on the right track

Navy Tests Incredible Sci-Fi Weapon | LiveScience

Lefty

 

[Hero999]

A voltage trippler on 120VAC will give you 500V.

You could add a 0-150V variac to the input of your trippler to get a variable 0 to 636V supply but watch you don't blow the capacitors.

That brings up another point are your capacitors rated to 600V and no more?

Remember that the voltage rating is an absolute maximum rating so make sure it isn't exceeded, always give about 25% headroom

If you want to get 600V very accurately, then build yourself an SMPs - it's the only sensible way.

 

[Krumlink]

I am using 2 400V caps in series to give me around 800V. 600V gives me plenty of room.

 

[Dean Huster]

Voltage multipliers are rarely capable of much current unless you use REALLY BIG capacitors in the circuit and the load demand isn't too long.

Dean

 

[Krumlink]

I am looking for a portable solution (no 120VAC) that can run off 1 and in worst case scenario 2 12V18AH batteries. Total estimated requirements: 600VDC-800VDC at 960uf.

I can wind my own xformer and anything else that is required. its been done before, but I cannot find the circuitry that they did it with.

 

[erosennin]

You want to step up a DC source???
Invert it to AC and step it up like that, because I don't think anyone makes DC to DC converters of such magnitude...
Also take into consideration that Xformers don't like square wave inputs much so you will need to develop a sine inverter...

At least I think that's what would be required, someone back me up/correct me on this...

 

[Mikebits]

Transformers can handle squarewaves just fine. Look at any flyback converter design.

 

[Krumlink]

yes, but how do/should I generate the 600-800VDC?

 

[Mikebits]

Maybe you can get some insight from the following article.
**broken link removed**

 

[Ubergeek63]

Transformers can handle squarewaves just fine. Look at any flyback converter design.

Actually they can't. It depends on the frequency and response of the transformer how good it looks on the output.

To a LF square wave to a HF transformer is DC. You end up shorting the input with the output differentiated.

Put a HF square wave into an AC line transformer and you get almost nothing out.

 

[Hero999]

I am using 2 400V caps in series to give me around 800V. 600V gives me plenty of room.

You could use a couple of mains transformers, providing they have twin 120V primaries (for operation at either 120V or 240V). This will give you about 450V (if you take into account the losses in the transformers) which you can rectify to give about 636V.

Note that the circuit attached is niether isolated nor current limited and touching the live output is likely to kill you, use at your own risk.

 

[joshua17ss2]

Have you consided using a camera flash charger, 1 for each of the capacitors, the can change it up to 330 volts each, you would probably need to change it for higher current, but it would get you the voltage level that you need.

 

[Krumlink]

camera flash chargers are inadequate for charging 800VDC 235uf capacitors. They have a low current output and would take up space.

I am looking for a high frequency transformer solution that can generate 800VDC from 12 even 24VDC.

 

[Mikebits]

Here is a link for the xformer used in the above mentiond circuit.
https://www.electro-tech-online.com/custompdfs/2008/05/453f0091-4eeb-4ee7-b33c-b689416a62c7.pdf

 

[Hero999]

You could use a cold cathode tube inverter with a variable DC voltage on the input and a rectifier on the output.

 

[RODALCO]

Use an old microwave transformer perhaps.

That usually steps up the 110V or 230V mains voltage to about 2200 Volts !!

Run the primary at about 1/5 th of the mains voltage and you have after rectification around 600 Vdc.

Be very carefull, these voltages will kill !!

 

[Krumlink]

Your making this too big, I need a small PSU yet capable of charging a 960uf 800VDC capacitor bank in a somewhat respectable time (lol no 20 hr charge time)

 

[dknguyen]

MIL-2132 - Original Military Hand Crank Generator Type 65 10 Watts of Power 1960's Chinese - Manufactured by: Military

It's 60 lbs though...would run as long as you do though!