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Calculate impedance variation

Posted Nov 13, 2019, 12:13 p.m. EST Electromagnetics, Low-Frequency Electromagnetics, Parameters, Variables, & Functions Version 5.2a 6 Replies

Enver Salkim
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Hi,

I would like to calculate impedance variation on a specified boundary based on time dependent study. The way of finding the impedance variation is to calculate elecrtical potential variation and divided this results by terminal current. I am not sure this is the correct way and also model give singularity problem. The model was attached Can you please guide me regaridng that?

Thank you in advance

Enver

6 Replies Last Post Dec 9, 2019, 6:36 a.m. EST
Dave Greve
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Posted: 5 years ago Nov 13, 2019, 5:06 p.m. EST
Updated: 5 years ago Nov 13, 2019, 12:06 p.m. EST
  1. If you want to calculate impedance you should be doing a frequency dependent (sinusoidal steady state) study.
  2. In many modules you can assign a Terminal boundary condition and the terminal impedance is available as a global variable.
  3. There was no model attached. Be sure to remove the solutions before posting.
1. If you want to calculate impedance you should be doing a frequency dependent (sinusoidal steady state) study. 2. In many modules you can assign a Terminal boundary condition and the terminal impedance is available as a global variable. 3. There was no model attached. Be sure to remove the solutions before posting.
Enver Salkim
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Posted: 5 years ago Nov 14, 2019, 5:05 a.m. EST
Updated: 5 years ago Nov 14, 2019, 5:07 a.m. EST

Hi Dave,

Thank you for reply. Sorry, it was my mistake. The model was attached. Would it be possible to look at the model? I have defined bipasic stimulus pulse and applied a boundary.

Kind regards, Enver

Hi Dave, Thank you for reply. Sorry, it was my mistake. The model was attached. Would it be possible to look at the model? I have defined bipasic stimulus pulse and applied a boundary. Kind regards, Enver
Dave Greve
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Posted: 5 years ago Nov 14, 2019, 10:16 a.m. EST
Updated: 5 years ago Nov 14, 2019, 5:16 a.m. EST

See #1. You can only calculate an impedance for sinusoidal excitation. Impedance is only defined for sinusoidal steady state excitation.

See #1. You can only calculate an impedance for sinusoidal excitation. Impedance is only defined for sinusoidal steady state excitation.
Enver Salkim
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Posted: 5 years ago Nov 18, 2019, 5:40 a.m. EST

Hi Dave,

Thank you for your comment. I have to apply bihasic rectangular signal as an input. Do you mean I can not calculate impedance if I apply any types of signals wavefrom but sinusoidal?

Kind regards, Enver

Hi Dave, Thank you for your comment. I have to apply bihasic rectangular signal as an input. Do you mean I can not calculate impedance if I apply any types of signals wavefrom but sinusoidal? Kind regards, Enver
Dave Greve
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Posted: 5 years ago Nov 18, 2019, 3:24 p.m. EST
Updated: 5 years ago Nov 18, 2019, 10:24 a.m. EST

Hi Dave,

Thank you for your comment. I have to apply bihasic rectangular signal as an input. Do you mean I can not calculate impedance if I apply any types of signals wavefrom but sinusoidal?

Kind regards, Enver

That is exactly what I am saying. Impedance is defined as the ratio of the (complex) voltage phasor to the (complex) current phasor. Phasors represent a sinusoidal signal that has been applied for a very long time.

>Hi Dave, > >Thank you for your comment. >I have to apply bihasic rectangular signal as an input. Do you mean I can not calculate impedance if I apply any types of signals wavefrom but sinusoidal? > >Kind regards, >Enver That is exactly what I am saying. Impedance is defined as the ratio of the (complex) voltage phasor to the (complex) current phasor. Phasors represent a sinusoidal signal that has been applied for a very long time.
Enver Salkim
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Posted: 5 years ago Dec 9, 2019, 6:36 a.m. EST
Updated: 5 years ago Dec 9, 2019, 6:37 a.m. EST

Hi Dave,

Thank you for your suggestions. Do I need to just apply preiodic sinusoidal signal to a boundary then calculate impedance variation (I belive I can do terminal voltage/terminal current ) or do I need to define an equation for the impedance variation? If it is possible, can you please guide me on my model?

Kind regards, Enver

Hi Dave, Thank you for your suggestions. Do I need to just apply preiodic sinusoidal signal to a boundary then calculate impedance variation (**I belive I can do terminal voltage/terminal current** ) or do I need to define an equation for the impedance variation? If it is possible, can you please guide me on my model? Kind regards, Enver

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