Switching 2000 Volts

Discussion in 'General Electronics Chat' started by Levitylab, Jun 6, 2014.

  1. Levitylab

    Thread Starter New Member

    Mar 16, 2013
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    I would like to use a solid state switch to discharge a bank of eight 250 volt/560 microfarad capacitors, wired in series, into a load. Currently, I am using a 40TPS12A SCR, rated at 1200 volts/40 amps to discharge a bank of four of these same capacitors, wired in series, into my load, which, effectively, is a short circuit. But, scouring the internet, it looks like the highest rated SCR is 1400 volts. Is there any other device that would satisfy my requirements?
     
  2. timwhite

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    Apr 10, 2014
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  3. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    What will be the load, where you want to dump all enery in?
    You might run in violation of the ToS.

    Bertus
     
  4. BobTPH

    Active Member

    Jun 5, 2013
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    A rail gun would be my bet.

    Bob
     
  5. timwhite

    Member

    Apr 10, 2014
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    Well in that case, NEVERMIND MY POST. :D
     
  6. Levitylab

    Thread Starter New Member

    Mar 16, 2013
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    Thanks for the replies, I'll check out the links after I do my daily bike ride, which I'm just about to head out on.

    Actually, it's a bit of an esoteric project, that I've been pursuing for several years, off and on. Back in 1996 a Russian materials scientist, by the name of Evgeny Podkletnov, claimed to have observed a 0.05% drop in the force of gravity above a rotating superconductor, while he was working in Finland.

    Later he modified the setup by discharging 2 million volts from a copper plate, about a foot in diameter, to a similar sized YBCO superconductor disc, some distance away. Allegedly, a distant target, consisting of a solid rubber ball suspended on a thread, was physically displaced a small amount. When his physicist assistant calculated the force required, they concluded a "gravitational impulse" of about 100 microseconds duration and 1000 g's was produced, in a collimated beam.

    My intent is to try essentially the same experiment, but with lower voltages and currents. By simple scaling, assuming there is any truth to these claims, I was hoping to see something in the neighborhood of about 1 g, which should be easy to detect with the commercial accelerometer that I'm using. Even if it's only 1/10th of that it should be recognizable.

    As far as the 'load', I had two ideas in mind. 1) Directly discharge the 2000 volts through the superconductor by pressing flat, metal plates on either side of it, connected between ground and the output of the SCR. I've been stymied in this approach by not being able to find a YBCO disc that is perfectly flat. They are always warped, presumably from the high heat used in their fabrication.

    Assuming I'm unable to find a flat YBCO, or have one specially made, the second option is: 2) Create a spark gap between the superconductor and a metal plate, maybe 1/4 to 1/2 inches away. Or, alternatively, if I can't make good electrical contact with the YBCO disc put metal plates on either side of it, spaced a small distance away, and discharge the voltage right through the superconductor.

    Here's my project's URL: http:www.starflight1.freeyellow.com

    I've actually posted before on this project with regard to some timing problems. Those were long ago solved.
     
    Last edited: Jun 6, 2014
  7. alfacliff

    Well-Known Member

    Dec 13, 2013
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    is it possible that the discharge of 2 million volts made an acustic wave that moved the suspended ball? that would have been quite a bang.
     
  8. bertus

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  9. Alec_t

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    Assuming the original experiment was not conducted in a vacuum I would think that's a more likely explanation for the ball movement. The laboratory walls could have had a focussing effect on the acoustic pulse.
     
  10. Levitylab

    Thread Starter New Member

    Mar 16, 2013
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    That's a good thought. In my early experiments I was plagued by much the same problem; trying to distinquish between the acoustic 'bang' produced by the sudden expansion of the liquid nitrogen in the cryostat and any, hoped for, genuine signal. In my experiments it was a serious problem as the accelerometer detector was only about 5 inches from the cryostat. But I resolved the problem by syncing the scope, which was monitoring the accelerometer output, to the actual moment of capacitor bank discharge, so I was easily able to separate the acoustic impulse from the sought for signal. This strategy assumed the anomalous signal propagates at light speed, or some sizable fraction of light speed. In the papers written by Podkletnov, and his physicist colleague Giovanni Modenese, it's indicated the phenomena propagates at light speed, as I recall.

    bertus:

    Thanks for mentioning the HTS tape. I actually did look into that, possibly the same company, it's been a while. I've forgotten what happened exactly, but I believe I contacted them, but never had a response. I think I'll look into that again. That would solve all my problems as the tape is, I assume, perfectly flat.

    As for liquid helium, that would be another way to get around the flatness problem, since Niobium, a superconducting metal, can be bought in all kinds of shapes, sheet, bar, etc. I haven't gone to your links yet, but I've known for a long time that liquid helium requires special handling and equipment. I thought about making up a mechanical jig with the superconductor secured to a frame and anode attached close by, that would enable me to simply dunk the jig into a vessel filled with liquid helium. I could then simply take this jig, and my portable accelerometer, scope, etc., to a laboratory that works with liquid helium. I live in southern New Hampshire, so I'm sure there are labs in the Boston area, or possibly the Nashua area, that work with liquid helium. That's another possible option.
     
  11. Levitylab

    Thread Starter New Member

    Mar 16, 2013
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    I just read the portion of the paper written by Giovanni Modenese and Evgeny Podkletnov, and it states that the suspended "targets" were placed in an evacuated cylinder. Additionally, the superconductor is placed in a partially evacuated chamber. It's also mentioned that some of the sensing devices (not specified) are placed as far as 150 meters from the superconductor containing chamber, and within another building.

    So it looks like they have pretty well eliminated sound impulses as the source of the phenomena they claim to have seen.

    Here's the URL for their paper. I know that they conducted further experiments after this report, but I will have to scan the internet to find them: http://arxiv.org/pdf/physics/0108005v2.pdf
     
  12. Lestraveled

    Well-Known Member

    May 19, 2014
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    Back to your original question: how do I switch 2000 volts.

    In the 80s I built a modulator for a radar transmitter. I stacked 1000 volt Mosfets in series. Each Mosfet had its own floating power supply, gate driver and opto-isolator. I used a capacitive divider tree to force the Mosfets to equally divide the voltage.
    Later I discovered that another company went to 10 KV with the same technique but used magnetics instead of opto-isolators. Interested?

    Mark
     
    Last edited: Jun 6, 2014
  13. ronv

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  14. nsaspook

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    Making an anti-gravity device is trivial, most of our butts are sitting on one called a chair. Weight is not important, mass is. They don't claim to alter the gravitational mass of the object. I can alter my weight on a scale by jumping up but my gravitational mass is constant. Nothing here suggests anti-gravity, I would suspect electromagnetic effects with rotating superconductors at those power levels so if you do build this thing be very careful.

    "They laughed at Galileo. They laughed at Newton. But they also laughed at Bozo the Clown." -- Carl Sagan.
     
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