Menu

Discussion Forum

New Discussion
Filter

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Piezoelectric Coupled With A Shunt Circuit For Vibration Damping

Posted May 6, 2019, 3:22 p.m. EDT 3 Replies

Yongchen Tai
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hi, I have been using comsol to study topics related to piezoelectric materials. I'm modelling a beam with a piezo attached on the top, and an electrical circuit attached to the patch: to do so I used the solid mechanics (solid), electrostatic (es) and circuit (cir) modules. I want to perform the eigenvalue analysis (I want to extract the dispersion using my model as a periodic cell...) it doesn't work and it says that one equation is missing ("Singular matrix. - Detail: There are 1 void equations (empty rows in matrix) for the variable comp1.es.term1.Q0_ode. at coordinates: (0,0), ... "). The implementation is ok for time domain study. Do you have any ideas?

The piezo-shunt is implemented as follows: the bottom face of the piezoelectric patch (attached to the beam) is grounded (es.ground), the upper one is connected to a circuit terminal (es.terminal 1 - type circuit), then a resistor and a inductor (in cir) is connected in series from node 0 (ground) to node 1 which is in turn connected to the terminal (in es) through a "External I - Terminal" connection (selecting terminal 1 for the electric potential).

Please see the attached file for details.

Thanks, Yongchen

Attachments:

3 Replies Last Post Sep 6, 2019, 5:04 a.m. EDT
Yongchen Tai
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 6 years ago May 6, 2019, 5:23 p.m. EDT

Hi everyone,

I made a change in the electrostatics(es). I disabled terminal. Instead of using that, I chose floating potential which can also be connected to external I-terminal I. Then, no error will occur. Can I simply do that? Can anyone tell the difference between terminal and floating potential?

Thanks, Yongchen

Hi everyone, I made a change in the electrostatics(es). I disabled terminal. Instead of using that, I chose floating potential which can also be connected to external I-terminal I. Then, no error will occur. Can I simply do that? Can anyone tell the difference between terminal and floating potential? Thanks, Yongchen
Yongchen Tai
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 6 years ago May 7, 2019, 12:04 p.m. EDT

Hi everyone,

I find out the problem is that the electric circuit interface (cir) doesnt support eigenfrequency study. It only support stationary, time dependent and frequency domain studies.

Thanks yongchen

Hi everyone, I find out the problem is that the electric circuit interface (cir) doesnt support eigenfrequency study. It only support stationary, time dependent and frequency domain studies. Thanks yongchen
Feng Xiao
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 5 years ago Sep 6, 2019, 5:04 a.m. EDT

Hi, I am facing the same problem. I want to perform the eigenvalue analysis (I want to extract the dispersion using my model as a periodic cell...) .But the electric circuit interface (cir) doesnt support eigenfrequency study.So did you have some good solution and could you tell me how to solve this problem.The importent is that how to get band gap.

Thanks

>Hi, >I am facing the same problem. >I want to perform the eigenvalue analysis (I want to extract the dispersion using my model as a periodic cell...) .But the electric circuit interface (cir) doesnt support eigenfrequency study.So did you have some good solution and could you tell me how to solve this problem.The importent is that how to get band gap. > >Thanks

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.

Suggested Content