Re: [TCML] ideas needed for using 3 SMPS NSTs (10 kV, 30 mA)

[Steve Ward <steve.ward@xxxxxxxxx>]

Bert,

The caps see 2X Vpk input, except for the very first "AC" coupling cap.

Having just repaired several glassman HV supplies at work, this fact is
quite fresh in my mind ;-)

Steve

On Tue, Jan 5, 2010 at 12:26 PM, Bert Hickman <bert.hickman@xxxxxxxxxx>wrote:

> Hi Thomas,
>
> The voltage rating of each diode must be _at least_ 2 times the peak output
> voltage of the HV supply. For the 10 kVrms SMPS supplies mentioned in the
> original thread, if the supply outputs a (mostly) sinusoidal waveform, 2 x
> Vpk would be about 3 x Vrms (rounding 28 kV upwards to 30 kV). However, I'd
> suggest using a rectifier (diode chain) rated for a reverse voltage of at
> least 3.5 - 4 x Vrms (or 35 - 40 kV) to provide healthy system margin and
> robustness.
>
> In a standard cascade C-W multiplier (using equal-value capacitors/stage),
> each capacitor must be rated for _at least_ the peak voltage of the HV
> supply (or 15 kV for a 10 kVrms sinusoidal source). I'd suggest using
> capacitors rated for at least 2 x Vrms (20 kV) to provide good margins and
> robustness. BTW, note that there are some other multiplier circuit variants
> (such as Greinacher multipliers) that apply progressively higher voltages
> across the DC stage caps.
>
> Some additional sites you may find useful:
>
> Theory and component rating:
> http://www.eettaiwan.com/ARTICLES/2001JUN/2001JUN14_AMD_AN2009.PDF
> http://hep.uchicago.edu/~rosner/p226/proj09/voltmult.pdf<http://hep.uchicago.edu/%7Erosner/p226/proj09/voltmult.pdf>
>
> Java-based C-W calculator:
> http://www.cosmicrays.org/muon-cockroft-walton-calculation.php
>
>
> Bert
> --
> ***  /\  ******************************************************
> __  _\/_  __  *     *     *     *     *     *     *     *     *
> \_\/_/\_\/_/  We specialize in UNIQUE items! Coins shrunk using
>  /\_\/_/\    ultra-strong magnetic fields, Captured Lightning
>  _\/_/\_\/_   (Lichtenberg Figures), & technical Books. Please
> /_/\_\/_/\_\  come visit us at http://www.capturedlightning.com
>     /\       *     *     *     *     *     *     *     *     *
> ***  \/  ******************************************************
>
> jhowson4@xxxxxxxxxxx wrote:
>
>> Hey guys i have one of those solid state neon transformers as well,
>> and i too was looking for something useful to do with it. voltage
>> multiplier seems like a good idea. especially since i have a ton of
>> 2kv .5A diodes and 2kv .01uf ceramic caps laying around. the
>> transformer is rated for 6kv 30ma
>>
>> I know this is not a tesla coil question so respond to my e-mail at
>> jhowson4@xxxxxxxxxxx
>>
>> How do you determine the voltage ratings for the diodes and the
>> capacitors needed in the multiplier circuit? I have looked on the
>> internet for an answer and have yet to find a clear one. Will the
>> stuff i have work.
>>
>> thanks in advance , Jay Howson
>>
>>
>>
>>
>>
>>
>> Hi Thomas,
>>
>> The high frequency (20+ kHz) output is ideal for driving a Cockroft-Walton
>> (C-W) Voltage Multiplier, since smaller HV capacitors
>>  can be used in each stage. The following web page provides useful
>> C-W design info for both half and full wave C-W multipliers:
>>
>> http://www.blazelabs.com/e-exp15.asp
>>
>> Bert
>>
>
> _______________________________________________
>
> Tesla mailing list
> Tesla@xxxxxxxxxx
> http://www.pupman.com/mailman/listinfo/tesla
>
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla