Re: Multisection HV terminal (fwd)

[<sroys@xxxxxxxxxxxxxxxxx>]

---------- Forwarded message ----------
Date: Mon, 22 Nov 2004 22:46:01 -0600
From: Dr. Resonance <resonance@xxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Multisection HV terminal (fwd)


I've also wrestled with the problem of making a large HV terminal,
especially one that can be manufactured for a reasonable cost.

One of the best designs for very large terminals is a long cylinder that is
horizontal.  A 60 inch dia. rolled aluminum cylinder with a pair of
hemi-circle endplates makes a great HV terminal.  Costs for the hemispheres
are reasonable and the cylinder in relatively inexpensive as compared to
spinning large spheres and oblates.

For Van de Graaff applications this design allows you to use very wide belts
up to 40 inches in width for rapid charge and very high terminal currents.

The Quebec design sounds simple until you consider all the "stalks" that are
required to support the plates.  Getting these angles correct and getting
inside the beast to do all the welding is very tough.

Dr. Resonance


> >Hi,
> >
> >In big HV lab they often used hv terminal maid of many small aluminium
> >curved plate, if you want a terminal 5 to 10 feet big it's more
> >practical to use this instead of a big spinning part. If the curve and
> >placement of the plate is right the terminal behave more or less like a
> >big single part terminal .  in the desing of these terminal you need to
> >shape and place the small plates in a way that they sheild each other
> >border.
> >
> >I try to find information on how to build them to have max performance
> >without success.
>
>
> I too have looked for this kind of information.  I think it's all
empirical
> (someone comes up with a design that "seems to work", they build it, it
> works, and from then on, all the electrodes are built that way.  I've seen
> ones with lots of little rounded edge circular "tiles".
>
> Take a look at this brochure from Hydro Quebec:
>
http://www.hydroquebec.com/technology/ireq/varennes/pdf/high-voltage_lab.pdf
>
>
> >I know many of you like Antonio and other study electrostatic, Bruce
> >and Rogowski profiles. May be some of you could help.
> >
> >I probably can find a stock of cheap serving spoon,  may be I can use
> >them by bending the handle and arrenging them in a sphere shape.
>
> I was thinking of something like pizza pans or serving platters
> epoxied/welded/soldered to threaded rod.
>
>
>
>