# Discussion Forum

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## electric field and potential distribution

Hi

I have been working on a 3D (AC/DC) model of a insulator, and I am trying to verify the uniform potential and field distribution along the insulator surface.

I apply 33Kv voltage at HV end. I got result, in this result potential along the insulator surface is uniform distribution, i want field also uniform distribution along the surface.

5 Replies Last Post May 8, 2013, 10:09 AM EDT
Posted: 4 years ago

Hi,

the field is the gradient of the potential. So your request is not physical. A uniform potential gives zero field. A linear potential distribution gives a uniform field.

Cheers
Edgar
--
Edgar J. Kaiser
www.emphys.com

Posted: 4 years ago

Thank u sir

I apply 33Kv voltage at HV end. I got result, in this result potential along the insulator surface is linear distribution, but not uniform field distribution along the surface and also field at HV (33KV) terminal as same as ground terminal, why sir ?
i attach my model image.

Posted: 4 years ago

I would expect a higher field close to the terminals and the geometry is the same on both ends.

--
Edgar J. Kaiser
www.emphys.com

Posted: 4 years ago
Hi

In HV end : field is high bcoz 33Kv applied, but same field will occur in ground end (zero potential), why sir?

Posted: 4 years ago

Sure, your geometry is symmetric. It doesn't matter where HV and ground are connected.

But looking at your pictures, I think you are making a very basic mistake. You don't have an air volume around your device. So you confine the model into the interior of the device. That is probably not what you want.

Another hint: The device has axial symmetry. You can save tremendous memory and computing time by setting up this in 2Daxial geometry. And the precision of the results can be much better.

Cheers
Edgar

--
Edgar J. Kaiser
www.emphys.com

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