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Time dependent study on a 3D multiturn coil inside of an electrical circuit
Posted 30 lug 2013, 13:40 GMT-4 2 Replies
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Hello,
I am trying to model the voltage in function of time across a 3D multiturn coil inside of an electrical circuit. To do this I use the Magnetic Fields and the Electrical Circuit physics and a Time Dependent Study with a coil current calculation preceding it. In the electrical circuit there is a voltage source generating a pulse . Moreover, I have added in the Magnetic Field study a Gauge Fixing and a multiturn coil with a reference edge (the coil excitation is set to current from circuit and in the electrical circuit there is an External I vs. U). Finally, the initial value of the magnetic vector potential is 0 in x,y and z and there is magnetic insulation on the surfaces of the air box surrounding the coil.
When I try to run the simulation COMSOL 4.3b displays the following error message:
Failed to find consistent initial values.
Segregated group 2
Singular matrix.
For mesh-case 0 there are 113600 void equations (empty rows in matrix) for the variable mod1.mf.psi.
at coordinates: (-0.00949828,-0.0132493,-0.010552), (-0.00882481,-0.0125927,-0.0109472), (-0.00959674,-0.0126878,-0.0111544), (-0.00884992,-0.0132232,-0.0111593), (-0.00894054,-0.0125715,-0.0118075), ...
and similarly for the degrees of freedom (empty columns in matrix).
Last time step is not converged.
Has anyone any idea why this error occurs?
Thanks,
Frédéric
I am trying to model the voltage in function of time across a 3D multiturn coil inside of an electrical circuit. To do this I use the Magnetic Fields and the Electrical Circuit physics and a Time Dependent Study with a coil current calculation preceding it. In the electrical circuit there is a voltage source generating a pulse . Moreover, I have added in the Magnetic Field study a Gauge Fixing and a multiturn coil with a reference edge (the coil excitation is set to current from circuit and in the electrical circuit there is an External I vs. U). Finally, the initial value of the magnetic vector potential is 0 in x,y and z and there is magnetic insulation on the surfaces of the air box surrounding the coil.
When I try to run the simulation COMSOL 4.3b displays the following error message:
Failed to find consistent initial values.
Segregated group 2
Singular matrix.
For mesh-case 0 there are 113600 void equations (empty rows in matrix) for the variable mod1.mf.psi.
at coordinates: (-0.00949828,-0.0132493,-0.010552), (-0.00882481,-0.0125927,-0.0109472), (-0.00959674,-0.0126878,-0.0111544), (-0.00884992,-0.0132232,-0.0111593), (-0.00894054,-0.0125715,-0.0118075), ...
and similarly for the degrees of freedom (empty columns in matrix).
Last time step is not converged.
Has anyone any idea why this error occurs?
Thanks,
Frédéric
2 Replies Last Post 17 ago 2013, 02:36 GMT-4
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Posted:
1 decade ago
Just a guess - since you wrote
I would suggest you add a gauge fixing for A-field node. This might help with the variable psi.
For mesh-case 0 there are 113600 void equations (empty rows in matrix) for the variable mod1.mf.psi.
I would suggest you add a gauge fixing for A-field node. This might help with the variable psi.
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Posted:
1 decade ago
1, in the circuit, you may need to add an external resistor to ensure the convergence.
2, your error information shows that there is void equations, may be some domains in your model are not filled with correct materials, and if it is air domain, you 'd better set the onductivity as non-zero, like 1 or 10 to avoid a divergence.
3. sometimes, it is neccessary to set the initial vector potential as non-zero value, and it depends on your model.
2, your error information shows that there is void equations, may be some domains in your model are not filled with correct materials, and if it is air domain, you 'd better set the onductivity as non-zero, like 1 or 10 to avoid a divergence.
3. sometimes, it is neccessary to set the initial vector potential as non-zero value, and it depends on your model.