Problem with magnetic field, magnetostriction

Please login with a confirmed email address before reporting spam

Hi,

So Im trying to solve the core noise by magnetstriction in a three phase transformer. But Im having problems with the magnetic field. Directly when i try to solve it an An unexpected error occurred and its very hard to understand how to fix that anyone had same or any solutions?.

Tried to build the magnetic field same as this https://www.comsol.com/model/nonlinear-magnetostrictive-transducer-6063 But same thing An unexpected error occurred. And when i open log file its impossible to understand anything.

I would really need help on this problem.

  1. Coil Geometry Analysis
  2. Time dependent

16 Replies Last Post 2024年5月15日 GMT-4 12:03
Edgar J. Kaiser Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月13日 GMT-4 14:28

Hi Linus,

Those 'unexpected errors' can be cumbersome. I sometimes found that the model file is corrupted and it is not advisable to go ahead with the file that produced the error. I step back to the last version that did not show the error. Save often and use version numbers! Anyway, it is not possible to give any specific advice in your case without seeing the model.

Cheers Edgar

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Hi Linus, Those 'unexpected errors' can be cumbersome. I sometimes found that the model file is corrupted and it is not advisable to go ahead with the file that produced the error. I step back to the last version that did not show the error. Save often and use version numbers! Anyway, it is not possible to give any specific advice in your case without seeing the model. Cheers Edgar

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 04:35

Hi Linus,

Those 'unexpected errors' can be cumbersome. I sometimes found that the model file is corrupted and it is not advisable to go ahead with the file that produced the error. I step back to the last version that did not show the error. Save often and use version numbers! Anyway, it is not possible to give any specific advice in your case without seeing the model.

Cheers Edgar

Alright well if you could take a quick look it would be thankful, but it only happens when i add magnetostriction to the modell otherwise it computes fine.

>Hi Linus, > >Those 'unexpected errors' can be cumbersome. I sometimes found that the model file is corrupted and it is not advisable to go ahead with the file that produced the error. I step back to the last version that did not show the error. Save often and use version numbers! >Anyway, it is not possible to give any specific advice in your case without seeing the model. > >Cheers >Edgar Alright well if you could take a quick look it would be thankful, but it only happens when i add magnetostriction to the modell otherwise it computes fine.


Edgar J. Kaiser Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 06:20

You have a couple of issues in your model.

  • No piezomagnetic domain is defined for the core in the solid physics.
  • The solver is not defined
  • Compliance matrix, coupling matrix are all zero
  • Relative permeability is not defined

There may be other errors. I suggest you look into the nonlinear magnetostriction example in the application library to learn how to properly set up the magnetostriction part.

Cheers Edgar

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
You have a couple of issues in your model. - No piezomagnetic domain is defined for the core in the solid physics. - The solver is not defined - Compliance matrix, coupling matrix are all zero - Relative permeability is not defined There may be other errors. I suggest you look into the nonlinear magnetostriction example in the application library to learn how to properly set up the magnetostriction part. Cheers Edgar

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 06:59

You have a couple of issues in your model.

  • No piezomagnetic domain is defined for the core in the solid physics.
  • The solver is not defined
  • Compliance matrix, coupling matrix are all zero
  • Relative permeability is not defined

There may be other errors. I suggest you look into the nonlinear magnetostriction example in the application library to learn how to properly set up the magnetostriction part.

Cheers Edgar

Hello,

Well first i wanna say thanks, i will for sure take a look into that. But could i ask what do you mean with the solver is not defined?

Also where can i find the expression for Compliance matrix, coupling matrix? And Piezomagnetic coupling matrix, Voigt notation?

Also did you find any other parts missing in the solid mechanics? Like constraints etc?

>You have a couple of issues in your model. > >- No piezomagnetic domain is defined for the core in the solid physics. >- The solver is not defined >- Compliance matrix, coupling matrix are all zero >- Relative permeability is not defined > >There may be other errors. I suggest you look into the nonlinear magnetostriction example in the application library to learn how to properly set up the magnetostriction part. > >Cheers >Edgar Hello, Well first i wanna say thanks, i will for sure take a look into that. But could i ask what do you mean with the solver is not defined? Also where can i find the expression for Compliance matrix, coupling matrix? And Piezomagnetic coupling matrix, Voigt notation? Also did you find any other parts missing in the solid mechanics? Like constraints etc?

Edgar J. Kaiser Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 09:38

There wasn't any solver sequence, probably due to the missing piezomagnetic domain and the resulting error. COMSOL stopped before building the solver sequence.

Material data for magnetostriction is a difficult point. You can find data for the material used in the library example (a giant magnetostrictor like Terfenol, used for tranducers), but that is not valid for Iron. Iron and polycrystalline ferrous materials have a more complex magnetostrictive function. Also the current nonlinear magnetostrictive approach in COMSOL is not really suitable for materials like Iron, even if you had a magnetostrictive function. You may get a result but it is probably not correct.

I developed a method for the linear case with DC bias and a small AC perturbation, but this is not suitable for a transformer.

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
There wasn't any solver sequence, probably due to the missing piezomagnetic domain and the resulting error. COMSOL stopped before building the solver sequence. Material data for magnetostriction is a difficult point. You can find data for the material used in the library example (a giant magnetostrictor like Terfenol, used for tranducers), but that is not valid for Iron. Iron and polycrystalline ferrous materials have a more complex magnetostrictive function. Also the current nonlinear magnetostrictive approach in COMSOL is not really suitable for materials like Iron, even if you had a magnetostrictive function. You may get a result but it is probably not correct. I developed a method for the linear case with DC bias and a small AC perturbation, but this is not suitable for a transformer.

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 09:43

There wasn't any solver sequence, probably due to the missing piezomagnetic domain and the resulting error. COMSOL stopped before building the solver sequence.

Material data for magnetostriction is a difficult point. You can find data for the material used in the library example (a giant magnetostrictor like Terfenol, used for tranducers), but that is not valid for Iron. Iron and polycrystalline ferrous materials have a more complex magnetostrictive function. Also the current nonlinear magnetostrictive approach in COMSOL is not really suitable for materials like Iron, even if you had a magnetostrictive function. You may get a result but it is probably not correct.

I developed a method for the linear case with DC bias and a small AC perturbation, but this is not suitable for a transformer.

Could i use another material for the core then to get it to work?

>There wasn't any solver sequence, probably due to the missing piezomagnetic domain and the resulting error. COMSOL stopped before building the solver sequence. > >Material data for magnetostriction is a difficult point. You can find data for the material used in the library example (a giant magnetostrictor like Terfenol, used for tranducers), but that is not valid for Iron. Iron and polycrystalline ferrous materials have a more complex magnetostrictive function. >Also the current nonlinear magnetostrictive approach in COMSOL is not really suitable for materials like Iron, even if you had a magnetostrictive function. You may get a result but it is probably not correct. > >I developed a method for the linear case with DC bias and a small AC perturbation, but this is not suitable for a transformer. Could i use another material for the core then to get it to work?

Edgar J. Kaiser Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 10:20

Transformer cores are made from Iron, so I am afraid you can't.

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Transformer cores are made from Iron, so I am afraid you can't.

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 10:37

Transformer cores are made from Iron, so I am afraid you can't.

How about grain oriented electrical steel? Im thinking the silicon steel GO 3%

>Transformer cores are made from Iron, so I am afraid you can't. How about grain oriented electrical steel? Im thinking the silicon steel GO 3%

Edgar J. Kaiser Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 11:27

Do you have its coupling matrix?

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Do you have its coupling matrix?

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 12:55

Do you have its coupling matrix?

No, will have to research if its possible to find.

>Do you have its coupling matrix? No, will have to research if its possible to find.

Edgar J. Kaiser Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 15:05

Here is some good reading about magnetostriction. It is mostly about magnetostrictive transducers, not about transformers. However, it shows the magnetostrictive function of a typical low carbon steel (page 25) and how to derive a coupling matrix from that. It is good for general understanding, but will be a long way to model magnetostriction in a transformer.

Hirao, M., Hirotsugu, O., Electromagnetic Acoustic Transducers, Springer Series in Measurement and Science Technology, ISBN 978-4-431-56034-0.

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Here is some good reading about magnetostriction. It is mostly about magnetostrictive transducers, not about transformers. However, it shows the magnetostrictive function of a typical low carbon steel (page 25) and how to derive a coupling matrix from that. It is good for general understanding, but will be a long way to model magnetostriction in a transformer. Hirao, M., Hirotsugu, O., Electromagnetic Acoustic Transducers, Springer Series in Measurement and Science Technology, ISBN 978-4-431-56034-0.

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月14日 GMT-4 18:54

Here is some good reading about magnetostriction. It is mostly about magnetostrictive transducers, not about transformers. However, it shows the magnetostrictive function of a typical low carbon steel (page 25) and how to derive a coupling matrix from that. It is good for general understanding, but will be a long way to model magnetostriction in a transformer.

Hirao, M., Hirotsugu, O., Electromagnetic Acoustic Transducers, Springer Series in Measurement and Science Technology, ISBN 978-4-431-56034-0.

Read thru it but still is it even possible to find desired magnetoelastic properties for Silicon Steel GO M-6 Rolling on internet?

Also could i ask you quick do i need some constraints in the solid? Or can i just leave it free

>Here is some good reading about magnetostriction. It is mostly about magnetostrictive transducers, not about transformers. However, it shows the magnetostrictive function of a typical low carbon steel (page 25) and how to derive a coupling matrix from that. It is good for general understanding, but will be a long way to model magnetostriction in a transformer. > >Hirao, M., Hirotsugu, O., Electromagnetic Acoustic Transducers, Springer Series in Measurement and Science Technology, ISBN 978-4-431-56034-0. Read thru it but still is it even possible to find desired magnetoelastic properties for Silicon Steel GO M-6 Rolling on internet? Also could i ask you quick do i need some constraints in the solid? Or can i just leave it free


Edgar J. Kaiser Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月15日 GMT-4 03:21

In a time dependent study the solid can be free, in a stationary study the rigid body DOFs must be constrained.

I was doing extended research regarding magnetostrictive properties in the internet, but didn't find much relevant. You may consider to inquire with manufacturers. Of course it is possible to measure magnetostrictive properties of specific materials. Then you still need a nonlinear method that can handle the non-monotonous behavior of Iron based materials.

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
In a time dependent study the solid can be free, in a stationary study the rigid body DOFs must be constrained. I was doing extended research regarding magnetostrictive properties in the internet, but didn't find much relevant. You may consider to inquire with manufacturers. Of course it is possible to measure magnetostrictive properties of specific materials. Then you still need a nonlinear method that can handle the non-monotonous behavior of Iron based materials.

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月15日 GMT-4 11:19

In a time dependent study the solid can be free, in a stationary study the rigid body DOFs must be constrained.

I was doing extended research regarding magnetostrictive properties in the internet, but didn't find much relevant. You may consider to inquire with manufacturers. Of course it is possible to measure magnetostrictive properties of specific materials. Then you still need a nonlinear method that can handle the non-monotonous behavior of Iron based materials.

Hey,

Well i did research myself and hardly found anything. I will take a consideration tomorrow about what to do but i think its way too big task considering the time i have left on my project.

Also just another question when i tried to solve the FFT, time to frequency. degrees of freedom solved for are zero? I mean I'm using the initial expression and input study as the time dependet. Values of dependent variables (Physics controlled). Should that get the displacement? Even if i have wrong material and getting result that are not correct. the FFT solver operates on dependent variables right? In my case there is already a dependent variable that can be input into the FFT solver, that is the solution variable (magnetic vector potential) from study 1? But still freedom solver for 0 and getting no output? Is it becouse of the solid or what can it be?

>In a time dependent study the solid can be free, in a stationary study the rigid body DOFs must be constrained. > >I was doing extended research regarding magnetostrictive properties in the internet, but didn't find much relevant. You may consider to inquire with manufacturers. >Of course it is possible to measure magnetostrictive properties of specific materials. Then you still need a nonlinear method that can handle the non-monotonous behavior of Iron based materials. Hey, Well i did research myself and hardly found anything. I will take a consideration tomorrow about what to do but i think its way too big task considering the time i have left on my project. Also just another question when i tried to solve the FFT, time to frequency. degrees of freedom solved for are zero? I mean I'm using the initial expression and input study as the time dependet. Values of dependent variables (Physics controlled). Should that get the displacement? Even if i have wrong material and getting result that are not correct. the FFT solver operates on dependent variables right? In my case there is already a dependent variable that can be input into the FFT solver, that is the solution variable (magnetic vector potential) from study 1? But still freedom solver for 0 and getting no output? Is it becouse of the solid or what can it be?

Edgar J. Kaiser Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月15日 GMT-4 11:59

This is now a different topic and I recommend to open a new thread. As your model is pretty complex I advise to set up something simple and test the FFT. You may find an example in the application library too.

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
This is now a different topic and I recommend to open a new thread. As your model is pretty complex I advise to set up something simple and test the FFT. You may find an example in the application library too.

Please login with a confirmed email address before reporting spam

Posted: 1 month ago 2024年5月15日 GMT-4 12:03

This is now a different topic and I recommend to open a new thread. As your model is pretty complex I advise to set up something simple and test the FFT. You may find an example in the application library too.

Alright, thanks!

>This is now a different topic and I recommend to open a new thread. As your model is pretty complex I advise to set up something simple and test the FFT. You may find an example in the application library too. Alright, thanks!

Reply

Please read the discussion forum rules before posting.

Please log in to post a reply.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.