Re: 500 KV DC (fwd)

[<sroys@xxxxxxxxxxxxxxxxx>]

---------- Forwarded message ----------
Date: Thu, 23 Sep 2004 09:42:50 -0500
From: Bert Hickman <bert.hickman@xxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: 500 KV  DC (fwd)

High Voltage list wrote:

> Original poster: <sroys@xxxxxxxxxxxxxxxxx>
> 
> 
> 
> ---------- Forwarded message ----------
> Date: Wed, 22 Sep 2004 20:56:22 -0300
> From: Antonio Carlos M. de Queiroz <acmdq@xxxxxxxxxx>
> To: High Voltage list <hvlist@xxxxxxxxxx>
> Cc: hvlist <hvlist@xxxxxxxxxxxxxxxxx>
> Subject: Re: 500 KV  DC (fwd)
> 
> High Voltage list wrote:
> 
> 
>>From: Bert Hickman <bert.hickman@xxxxxxxxxx>
> 
> 
>>Sounds like the easiest way would be to make a voltage doubler, using
>>at least 25 to 36 of your 20 kV rectifiers or 5-7 100 kV X-ray
>>rectifier sticks. Series stacks of at least 13 to 18 40 kV ceramic
>>(doorknob) caps can be used to make the HV caps. If you think you
>>might every try running the X-ray transformer at full input voltage,
>>you'll need to use the larger number of rectifier sticks and caps to
>>withstand the voltage stress (~705 kV).
> 
> 
> And how would someone insulate the 700 kV, or 500 kV? With 700 kV
> you need a sphere with about 50 cm of diameter just to avoid 
> ionization of the air.

Well, it wouldn't be a trivial design, for sure.  :^)

It would require a large insulated oil filled tank topped by a large 
toroid or oblate spheroid. An alternative might be a conductive tank 
topped with a huge graded oil bushing, tipped by the appropriate 
corona ring(s)...  similar to extra HV power sources produced by 
Haefely:
http://www.haefely.com/high_voltage_test/ac_test_transformer/index.html#acs
http://www.haefely.com/high_voltage_test/ac_resonance_test/index.html

BTW, I tried to talk the wife into letting me get a 300 kV AC test 
system (very cheap at the price!), but thus far no such luck:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=36351&item=3841334825

[Buy it and keep it at the neighbor's house until the appropriate time -
Christmas, your anniversary, her birthday...! It's (usually) easier to get
forgiveness than permission... ;-) SRR]
> 
> Antonio Carlos M. de Queiroz
> 
> 
> .
> 

-- Bert --
-- 
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