Homogenized Multiturn causing tolerance issues

Please login with a confirmed email address before reporting spam

Hello,

I am currently simulating my model using the Coil Geometry Analysis study in COMSOL. When I select the Single Conductor option for the coil, the analysis runs successfully.

However, I would like to proceed with a Time-Dependent study, which requires using the Homogenized Multiturn coil model. Since I have already modeled all the turns explicitly in the geometry, I set N = 1. But when I switch to the homogenized multiturn option and run the Coil Geometry Analysis, the solver returns the error “Failed to find a solution.”

Could you please suggest how to resolve this issue?

Thank you for your support.



3 Replies Last Post 2026年3月10日 GMT+8 15:55
Edgar J. Kaiser Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 19 hours ago 2026年3月9日 GMT+8 21:49

You can run a time-dependent study with the single conductor coil.

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
You can run a time-dependent study with the single conductor coil.

Please login with a confirmed email address before reporting spam

Posted: 3 hours ago 2026年3月10日 GMT+8 13:36

I am working with a planar-type coil modeled as a solid conductor in COMSOL. The coil is excited using a sinusoidal voltage source through an external I–U coupling.

The Coil Geometry Analysis study runs successfully. However, when I attempt to run a Time Dependent study, COMSOL returns the error:

"Current excitation is not supported in single conductor coils in time dependent studies."

To troubleshoot, I also tried removing the external circuit and directly applying a current excitation in the coil, but the same issue persists.

I have attached the corresponding .mph file for reference.

Could you please help me understand how to correctly set up the coil excitation for a time dependent study in this case?

Thank you for your time and assistance.

Best regards, Anushka Mahajan

I am working with a planar-type coil modeled as a solid conductor in COMSOL. The coil is excited using a sinusoidal voltage source through an external I–U coupling. The Coil Geometry Analysis study runs successfully. However, when I attempt to run a Time Dependent study, COMSOL returns the error: **"Current excitation is not supported in single conductor coils in time dependent studies."** To troubleshoot, I also tried removing the external circuit and directly applying a current excitation in the coil, but the same issue persists. I have attached the corresponding .mph file for reference. Could you please help me understand how to correctly set up the coil excitation for a time dependent study in this case? Thank you for your time and assistance. Best regards, Anushka Mahajan


Edgar J. Kaiser Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 1 hour ago 2026年3月10日 GMT+8 15:55
Updated: 1 hour ago 2026年3月10日 GMT+8 15:56

Anushka,

this coil geometry is not well suited for a multiturn coil. The coil geometry analysis has a very hard task to determine the current direction. The current excitation adds extra numerical complexity. Try the single conductor with voltage excitation. If possible make sure the time dependent voltage starts at zero and not at a non-zero value, to make convergence easier at the start of the time dependent step.

Cheers Edgar

P.S. you don't need to zip COMSOL files, they are zipped by themselves already.

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Anushka, this coil geometry is not well suited for a multiturn coil. The coil geometry analysis has a very hard task to determine the current direction. The current excitation adds extra numerical complexity. Try the single conductor with voltage excitation. If possible make sure the time dependent voltage starts at zero and not at a non-zero value, to make convergence easier at the start of the time dependent step. Cheers Edgar P.S. you don't need to zip COMSOL files, they are zipped by themselves already.

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.