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FrozenGate by Avery

dc-dc voltage step up HUGE!!!

Have you ever thought of using an automotive ignition coil? I know someone else that is using them for a similar purpose.
 





For the propelling coil, you mean? I just got my 0 aug wire for the coil, and, sadly, do not have any automotive ignition coils hanging about. Also, according to lens law, the flatter the coil the better! So I need a real pancake.
 
Average ignition coil outputs roughly 100 times the input voltage or a 100 to 1 ratio.
You should be able to get one at a junk yard pretty cheap.
This explains how a coil works. Ignition coil function and testing
Here is a video of someone using a coil for high voltage.



It is amazing what google can do for you!
 
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Did you know you can buy flat magnet wire, it's used to wind the armature on really big motors.


Lascannon said:
For the propelling coil, you mean? I just got my 0 aug wire for the coil, and, sadly, do not have any automotive ignition coils hanging about. Also, according to lens law, the flatter the coil the better! So I need a real pancake.
Click to expand...
 
Lascannon said:
Been there. thanks for pointing me in the direction of the car inverter! It turns out that some types invert after steping the voltage up. All I have to do it to pop the cover off and get my leads in before it inverts. With extreme care, of course.
Click to expand...

Virtually all modern inverters to this: The generate a DC voltage equal to the peak of the grid voltage (ca 200 volts for a 120 grid, 400 for a 230 grid). The 'modified sine' consists of little else that periodically switching this dc voltage to the output resulting in an alternating current.

If you pop something like that car inverter open, it would probably be quite easy to indentify the buffer capacitor used before the alternating part.

The actual 12v -> 200/400 volt process works at a high frequency and can use a very compact transformer, comparable to a switchmode power supply that does this trick the other way around.
 
Thanks guys! Couple of questions:

What would be the advantage of using flat wire? And would this stuff be capable of sustaining the 110 wats running through this thing?

Speaking of watts, the internal resistance of this much wire is going to be almost nothing, inscreasing my watts to an insane number, destroying the wiring. My plan was to put a 1ohm resistor somewhere, but I cant find one which will take 150 watts. Does anyone know if the capacitors have an internal resistence? And if so, how much?

Benm: Thanks alot for pointing me in the right direction!
 
00Giorge said:
Average ignition coil outputs roughly 100 times the input voltage or a 100 to 1 ratio.
You should be able to get one at a junk yard pretty cheap.
This explains how a coil works. Ignition coil function and testing


It is amazing what google can do for you!
Click to expand...

That would work if he needed a charge pump to crank up an oil filled 10kv cap. He only wants ~110 v. A boost converter or a mazilli flyback converter would suit his needs. With the mazilli with voltage cut-off, he could even set it to shut off the charge pump once it hits 110V.
 
The circuit i presented to you a while ago will do what you need. Theres also a more basic version, but I would suggest the one I suggested. It's desgined for 450 volts, but with a resistor change, it'll happily shut off @ 110V.

I can help you work out the resistor, and fix up a schematic sans all the fluff on the circuit that isnt needed.

but there is one problem. MY inverters are beginning to fail. I am no longer able to produce 400V to run all my system. They are whining like crazy due to low input voltage. Having been up for 72 hours straight, I hear my bed calling!

I'll be back after a good nights sleep :)
 
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Now I feel silly... but... what circuit?

So, my circuit as it is now: 12 volt battery > safety switch > vk2fro's unkown circuit > to capacitors in parallel > safety switch #2 > trigger switch > Coil.

Missing anything?

Sleep well! I am realy looking forward to continuing this tomorrow!

Edit: I cancellend my wire round order, can anyone suggest a wire gauge that wont burn out?

Thanks!
 
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Epic! Thats perfect! So... yea... thanks guys!

Can any tell me what wire size to use so as not to melt the coil into a pudle?

Thanks,
Liam.
 
Not sure what you mean there Liam - melt the coil into a puddle?

Are you talking about the inductor, or the transformer windings?

To simplify the circuit, remove the 2 680R resistors, the led, the two 1K resistors and the 15K resistors, along with the comparator, and the two pnp transistors. All these parts are to the right of the switch. The 12V connection which is left floating connects to the right of the 18K resistor near the switch.

Add a volt meter and you'll know what voltage your at (either a multimeter or panel meter. You can get these on ebay for about 9 bucks that go 0-200 volts DC, perfect for your project. I had to mod mine to read 1500 volts, so I just desoldered the decimal point, and made a 10:1 voltage divider :) (1250v in, 125v out). This is at the bank. so saves having to have HV wiring back to the control box.

You can get more details about a cap charger by looking at the thread entitled "big capacitor bank". I am doing exactly the same thing except at a much higher (and deadly LOL) voltage :)
 
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