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Transformer Impedance/Inductance Matrix

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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 16 sept. 2013, 10:31 UTC−4

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Posted: 1 decade ago 16 sept. 2013, 05:22 UTC−4

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.

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Posted: 1 decade ago 16 sept. 2013, 10:31 UTC−4
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...

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