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Best way to produce 1 million volts dc

  1. Apr 25, 2009 #1
    I'm wanting to build a dc power source of 1 million volts more would be nice but ill start with a million and work my way up from there. Any suggestions would be helpufull. Is it possible to build a 1 million volt capacitor or should i build a capacitor bank to smooth out the ac current after its rectified or do you have a better suggestion for me. I'm wanting to build a coil gun with 1 million volts and not have to wait for capacitors to charge all the time just want to have a high voltage supply and fire it whenever. Any help will be greatly appreciated.
  2. jcsd
  3. Apr 25, 2009 #2
    There are two basic methods to get 1 million volts DC. One way is to use the Van de Graaff approach with a moving belt. An example of this are the Emporer tandems (made by High Voltage Engineering), which have exceeded 10 million volts terminal voltage. See
    The other way is to use the Cockroft-Walton (or Marx generator) approach with a stack of high voltage diodes and capacitors for voltage multiplication. See
  4. Apr 25, 2009 #3
    i don't know much about those i'm looking for a constant dc power supply though not something i have to wait to charge back up or anything just something thats always there.
  5. Apr 25, 2009 #4
    It's not a good idea to work with high voltage if you don't know much about it, let alone work with 1 million volts.

    A rule of thumb is 10,000 volts per 1 cm of spark. At 1 million volts you will get 1 meter long sparks shooting around.

    Also, regardless what way you will generate high voltage, there will always be some capacitance involved. From basic physics, the energy stored in a capacitor is proportional to voltage squared. At 1 million volts, even a relatively small internal capacitance can unload a lethal charge.
  6. Apr 25, 2009 #5
    Here is a rather simple way to produce a high voltage, but not 1 million volts.

    1) Assemble a parallel plate capacitor in a tank with ultra pure water as dielectric.
    2) Charge up the plate to a high voltage.
    3) Drain out the water.

    This produces a very high voltage by decreasing the dielectric constant of the charged capacitor by a factor of about 80.
  7. Apr 26, 2009 #6
    Wouldn't you be drawing a ridiculous amount of power to achieve this. I would think a steady 1 million volts ps would require more then an average wall output.
  8. Apr 26, 2009 #7
    i don't know but thats what i need to do check out my other one talking about superconductors and high voltage it talks about what i want to do down in a reply i left. i have an idea to change the world i'm going to build it but i need your guys help to get it done. i don't care what power it takes or what i have to do to do it im going to do it. if you have any ideas it would be greatly appreciated.
  9. Apr 26, 2009 #8


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  10. Apr 26, 2009 #9
    I have an old (40 years?) Mark Ten B CD (capacitor discharge) igniton system that can generate roughly 30 kV from less than 1 amp at 12 volts. This circuit charges a capacitor to about 300 to 400 volts using a dc-dc converter, and dumps it into the primary of a 12-volt automotive ignition coil when an electronic switch is triggered. I get 2 cm sparks (2.5 on a good day) out of it. For spark voltages over 100 kV, I think a Tesla coil would be good choice. I had a high school classmate who built a small one (about 1 meter high) for a class project (with the teacher's help).
  11. Apr 26, 2009 #10
    I seem to recall that air at STP can withstand about 30KV per centimeter. One million volts would require a smooth conducting ball of two foot diameter to be charged to 1MV without arcing to infinity.
    Last edited: Apr 26, 2009
  12. Apr 27, 2009 #11


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    What'cha plannin' on shooting this coil gan at?
  13. Apr 27, 2009 #12
    i'm not planning on shooting any coil gun well maybe one or two just for fun. What i'm wanting to do with it though is i have an idea for a propulsion system using this. i talk about it in my other post of superconductors and high voltage
  14. Apr 30, 2009 #13
    Are you in essence storing the potential energy that the water had from gravity into additional energy per a charge as your dielectric changes from water to air?
  15. Apr 30, 2009 #14
    Go fly a kite in a thunderstorm.
  16. May 1, 2009 #15
    1 million volts is way too much for a coil gun except maybe if that coil gun is as big as a house.
    You only need a few thousand volts. You can build a power supply from a tv flyback transformer.
  17. May 1, 2009 #16
    Put 250 of THESE in series.
  18. May 1, 2009 #17
    Is there any way to increase the current of a Cockroft-Walton generator by adding tunnel diodes? I heard from someone years ago that a tunnel diode can increase current.
  19. May 1, 2009 #18
  20. May 2, 2009 #19
    I need the coils to have 1 million volts. I need a really powerful coil gun. But its not to shoot a projectile I want to but it on an aluminum ring with iron bolted to it in certain spots and make it spin as fast as I can. Will it eventually make it spin as fast as the magnetic field is generated. Thats why I want a steady supply and not something that you have to charge for one firing. I think a tesla coil might work can you wire that up to something. My idea is to use superconducting wire for the coils and some thick Mylar insulation. Go to superconductors.com and type 2 superconductors and check out the top one. Supposedly its superconducting at -40 degrees Fahrenheit. And put 1 million volts through those.
  21. May 2, 2009 #20


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    Don't know if this will help, but if you have a little time to look at the patents of a man that contributed so much in the early days, there is lots of mind stimulating drawings and wording in the body of his patents.

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