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Voltage multiplication using a battery

  1. Sep 14, 2011 #1
    Okay, so before when I asked a question about voltage multiplication, I was recommended a charge pump. But now I realize that creating a charge pump to get the voltage I want would be rather ridiculous. So, here is my problem: I need to get 1000vdc from a 9vdc battery, but I'm not entirely sure how to do this conveniently (well, more conveniently than a charge pump that is). Have any suggestions?


    Note: I don't want to convert to AC, otherwise, I wouldn't be asking this question.
     
  2. jcsd
  3. Sep 14, 2011 #2

    berkeman

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    What is the application? What kind of potential safety issues could you identify in this project for us?
     
  4. Sep 14, 2011 #3
    I suggested looking at charge pumps when I did not know your source or target.

    I can't imagine why you don't want to use a step up transfomer. A 9v battery can readily be persuaded to yield 500 to 1500 volts with a Hartley oscillator configuration, which is very simple. This is how many insulation testers work.

    But, since you eschew such methods, try a Wimshurst machine. You will not then need a battery at all, just a bit of muscle power.
     
  5. Sep 14, 2011 #4
    Lol, I knew I would be asked that. The application is for charging capacitors in a series, which are being used to power a coilgun. The potential safety issues aren't really an issue, as I have dealt with high voltage before, and know the safety precautions that I must take.
     
    Last edited: Sep 14, 2011
  6. Sep 14, 2011 #5
    I guess I wasn't very specific on my first question. Anyways, I need to charge capacitors in a series. I need the DC because that would require a inverter, a transformer, and a bridge rectifier, and I am rather limited on space and weight. So to combat this, I thought that a DC to DC converter would be a much better alternative. A whimshurst machine would make a good alternative, although the same issue with the space turns up.
     
  7. Sep 14, 2011 #6

    jim hardy

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    i dont know what is a whimshurst

    but take a look at how the flash unit works in a throwaway disposable camera.

    they turn 1.5 vdc into 400 vdc
    using a "flyback" converter

    how fast do you want to charge the cap?

    local photolab folks at grocery or drugstore will probably give you a grocery sack of old disposable cameras- put 9v to one and see what it'll do.

    But be careful, that photoflash capacitor in the camera will probably be charged and it's easy to get a surprisingly vigorous shock. Discharge it before you get very far nto disassembly..
     
  8. Sep 14, 2011 #7
    I am glad I'm not helping someone with this attitude power a coilgun.
    I retire from this thread, mods please feel free to delete my contributions (if any) so far.
     
  9. Sep 14, 2011 #8

    berkeman

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    Yeah, wanting to make a highly portable railgun in highschool. I think this thread is done.
     
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