Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

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.

Transformer Impedance/Inductance Matrix

Please login with a confirmed email address before reporting spam

Would anyone have a suggestion for how to start analyzing an COMSOL AC/DC magnetic circuit model to come up with an inductance matrix?

At first I thought I could use the port sweep, but it doesn't appear to work for this. I can get the results I'm looking for when I run one condition at a time, but I would like to set up a model with an arbitrarily large number of windings and run this as part of a parametric study.

Assume as a simple example, that I have a transformer with 4 windings.

V=Ldi/dt
or V=jwLI

[V1;V2;V3;V4] = jw [L11, L12, L13, L14; L21, L22 ... L44] [I1; I2; I3; I4]

How could I get comsol to calculate the 4x4 inductance matrix?


2 Replies Last Post Sep 16, 2013, 10:31 a.m. EDT

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Sep 16, 2013, 5:22 a.m. EDT

Would anyone have a suggestion for how to start analyzing an COMSOL AC/DC magnetic circuit model to come up with an inductance matrix?

At first I thought I could use the port sweep, but it doesn't appear to work for this. I can get the results I'm looking for when I run one condition at a time, but I would like to set up a model with an arbitrarily large number of windings and run this as part of a parametric study.

Assume as a simple example, that I have a transformer with 4 windings.

V=Ldi/dt
or V=jwLI

[V1;V2;V3;V4] = jw [L11, L12, L13, L14; L21, L22 ... L44] [I1; I2; I3; I4]

How could I get comsol to calculate the 4x4 inductance matrix?


May be you can try the parametric sweep when you tune the solver, and the current matrix [I1;I2;I3;I4] and voltage matrix [V1;V2;V3;V4] can be given as a lookup table.
[QUOTE] Would anyone have a suggestion for how to start analyzing an COMSOL AC/DC magnetic circuit model to come up with an inductance matrix? At first I thought I could use the port sweep, but it doesn't appear to work for this. I can get the results I'm looking for when I run one condition at a time, but I would like to set up a model with an arbitrarily large number of windings and run this as part of a parametric study. Assume as a simple example, that I have a transformer with 4 windings. V=Ldi/dt or V=jwLI [V1;V2;V3;V4] = jw [L11, L12, L13, L14; L21, L22 ... L44] [I1; I2; I3; I4] How could I get comsol to calculate the 4x4 inductance matrix? [/QUOTE] May be you can try the parametric sweep when you tune the solver, and the current matrix [I1;I2;I3;I4] and voltage matrix [V1;V2;V3;V4] can be given as a lookup table.

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Sep 16, 2013, 10:31 a.m. EDT
Unlike the example with the capacitance matrix in the Model library, you have to assign non-zero values to all your ports if you want to make use of the port sweep feature.

Assign, for example, 1 V to every port and COMSOL will use 1 V at the firtst port and 0 V at the remaining three ports in step 1. In Step 2 it will use 1 V at port #2 and 0 V at ports #1, #3 and #4. And so on.

In electrostatics, on the contrary, it is necessary to assign 1 V to one port and 0 V to the others and COMSOL will sweep the 1 V through all the ports.

This difference is hard to find out, if you start at the Model library example...
Unlike the example with the capacitance matrix in the Model library, you have to assign non-zero values to all your ports if you want to make use of the port sweep feature. Assign, for example, 1 V to every port and COMSOL will use 1 V at the firtst port and 0 V at the remaining three ports in step 1. In Step 2 it will use 1 V at port #2 and 0 V at ports #1, #3 and #4. And so on. In electrostatics, on the contrary, it is necessary to assign 1 V to one port and 0 V to the others and COMSOL will sweep the 1 V through all the ports. This difference is hard to find out, if you start at the Model library example...

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.