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How to AC oscillate a HV capacitor?

  1. May 19, 2013 #1
    I have read, analyzed and researched so much, my eyes and mind are on a breaking point , therefore, what I really want to know , how and why.. is perhaps best summoned in what I really want to do in the end. So lets cut to the chase:

    I just simply want make a HV capacitor oscillate at a high AC frequency?. How can I achieve that ?

    Example: I want a 400000v 20pf capacitor to oscillate at say a frequency of 200khz( i.e. make it charge to positive, get it to zero, make it charge to negative and get back to zero each cycle - NO SPARKS anywhere of course) . Does a 400 000v, 200khz tesla coil with a 20pf top- load do the job I need? (since the top load do that at that frequency or am I wrong?)

    I have been in this journey a long time now and despite hard work and dedication I feel I am reaching nowhere. I looked into LC circuits since there it seems that caps oscillate pretty quickly easily but I am not sure anymore about what I know. I do feel that I am reaching a dead end and I wish I could speak with someone knowledgeable about this to help me. To put it in another unpreferred way, I am reaching a rather desperate point. Your help is truly valued.

    Kind regards
     
  2. jcsd
  3. May 20, 2013 #2

    NascentOxygen

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    I suppose a Tesla coil will do that voltage and frequency, but it may be difficult to stop it sparking/discharging because air will break down with those voltages.
     
  4. May 20, 2013 #3
    Oh yes, stopping the top capacitance is an another problem. I just wanted to know for sure if a Tesla Coil´s top load oscillates at the resonant frequency at the Tesla Coil voltage. Insulating the capacitance in strong dielectric like mica or oil could help avoid sparkings maybe? It is the effects of air molecules bombardment around a rapidly alternating surface that I am interested in analyzing , not sparking or streamers
     
  5. May 20, 2013 #4

    berkeman

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    What in the world do you want to do this for?
     
  6. May 20, 2013 #5
    400 kV and 200 kHz sounds very difficult.
    Can you use a lower voltage and or a lower frequency?

    Just out of curiosity, at 400 kV how are you going to be able to get close enough to the surface to view molecules bombardment?

    Good Luck
    Carl
     
  7. May 20, 2013 #6

    psparky

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    Gold Member

    400,000 volts?

    Although it's not continuous, a HEI coil off a car produces like 50,000 volts....if you get hit by that your gonna know it. 8 times that amperage and wow......you better be careful....
     
  8. May 20, 2013 #7

    berkeman

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    Thread closed for Moderation...
     
  9. May 20, 2013 #8

    berkeman

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    Thread will remain closed. Discussions about DIY HV apparatus are a bit too problematic for the EE forum, IMO, because of the broad range of experience levels that folks have (it's the less experienced users that I'm concerned about).

    @leviterande -- The wikipedia page on Tesla Coils should answer your questions. Please pay particular attention to the section on "High frequency electrical safety".

    http://en.wikipedia.org/wiki/Tesla_coil

    .
     
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