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Multi coil domain- coil excitation by voltage does not depend on number of turns?

Posted Dec 8, 2016, 7:59 a.m. EST Version 4.3a 6 Replies

Vineeth Raj S
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Hello

In a multi-coil domain, using the magnetic field interface, when I give the coil excitation by voltage, I get a particular magnetic flux density. But when I change the number of turns, keeping the voltage constant, the magnetic flux density does not change. Why?

Kindly help.
6 Replies Last Post Dec 8, 2016, 9:30 a.m. EST
Mark Harradine
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Posted: 7 years ago Dec 8, 2016, 8:12 a.m. EST
Hi,

I assume you mean a multi-turn coil domain, right? If you have correctly specified that the coil should be driven by your user defined voltage, then you are right, the field should change when you change the number of turns.

Difficult to say exactly why without seeing your model, if you post it I can take a quick look to see what the issue might be...

Mark
Hi, I assume you mean a multi-turn coil domain, right? If you have correctly specified that the coil should be driven by your user defined voltage, then you are right, the field should change when you change the number of turns. Difficult to say exactly why without seeing your model, if you post it I can take a quick look to see what the issue might be... Mark
Mark Harradine
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Posted: 7 years ago Dec 8, 2016, 8:38 a.m. EST
Other things to check:

1) If you are plotting the field, make sure that your plot is using the correct dataset as its source. You may have used a parametric sweep to increase the voltage across a range, but your plot may be using a data set that was not created by your parametric sweep hence it looks like your field has not changed.
2) The attached file gives great guidance on multi turn coils in version 4.3a.

I have many coil models that I could share with you, but mine are all version 5.3a, looks like you are on 4.3a. Let me know if you have access to 5.3a and I can share some models that should help.

Are you in2D axisymmetric or 3D? Stationary of transient/time dependant?
Other things to check: 1) If you are plotting the field, make sure that your plot is using the correct dataset as its source. You may have used a parametric sweep to increase the voltage across a range, but your plot may be using a data set that was not created by your parametric sweep hence it looks like your field has not changed. 2) The attached file gives great guidance on multi turn coils in version 4.3a. I have many coil models that I could share with you, but mine are all version 5.3a, looks like you are on 4.3a. Let me know if you have access to 5.3a and I can share some models that should help. Are you in2D axisymmetric or 3D? Stationary of transient/time dependant?
Edgar J. Kaiser Certified Consultant
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Posted: 7 years ago Dec 8, 2016, 9:05 a.m. EST
If your coil domain remains at the same size, the resistivity of the coil rises as the number of turns rises. So with constant voltage the coil current drops and the field remains constant.

Cheers
Edgar

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
If your coil domain remains at the same size, the resistivity of the coil rises as the number of turns rises. So with constant voltage the coil current drops and the field remains constant. Cheers Edgar -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com
Mark Harradine
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Posted: 7 years ago Dec 8, 2016, 9:12 a.m. EST
Exactly right... I just realised I mis-read his first post. I thought he was increasing the voltage and not seeing any change in field, my mistake!

Mark

By the way, I have attached the file I referred to earlier as it is a useful reference anyway.

Exactly right... I just realised I mis-read his first post. I thought he was increasing the voltage and not seeing any change in field, my mistake! Mark By the way, I have attached the file I referred to earlier as it is a useful reference anyway.

Attachments:

Vineeth Raj S
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Posted: 7 years ago Dec 8, 2016, 9:30 a.m. EST
Thank you Sir :)
Thank you Sir :)
Vineeth Raj S
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Posted: 7 years ago Dec 8, 2016, 9:30 a.m. EST
Thank you Sir :)
Thank you Sir :)

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