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Resistance of a coil in 3D

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Hello,

I am performing 3D simulation of a power cable. I would like to compute resistance of my cable. I have done simulation of the same cable in 2D and I could compute resistance from coil parameters. However, in 3D I could not find expression for resistance. I would like to know if it is possible to evaluate resistance in 3D? Actually, I want to see if the resistances in 2D and 3D of the same cable are different. 3D simulation requires more memory and time, therefore, if the resistances in 2D and 3D will be the same then I want to run 2D simulation.
Also how can I calculate mutual inductance between two cables?
Thanks!

Regards,
Akim

12 Replies Last Post 2016/02/24 14:27 GMT-5

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Posted: 10 years ago 2014/06/13 7:24 GMT-4
dear Akim,
maybe you can upload your model. So it will be easier understand you. Next is, it's a DC or ac problemm. If ac problemm we should know the freqency and so far....
dear Akim, maybe you can upload your model. So it will be easier understand you. Next is, it's a DC or ac problemm. If ac problemm we should know the freqency and so far....

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Posted: 10 years ago 2014/06/15 3:55 GMT-4
Dear Viktor,

Thank you for your response. I have attached both 2D and 3D models, frequency is 60 Hz. I did not build mesh for 3D model because size of meshed model exceeds allowed size to upload.

Regards,
Akim
Dear Viktor, Thank you for your response. I have attached both 2D and 3D models, frequency is 60 Hz. I did not build mesh for 3D model because size of meshed model exceeds allowed size to upload. Regards, Akim


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Posted: 10 years ago 2014/06/16 5:23 GMT-4
Ok, i have your 2d and 3dmodel. I think this is difenitly a 2d Problem. The 3 cables have the exactly the same cabel or maybe it a 3phase curren width 120deg angle between the phases. see the model

sorry for my bad English
Ok, i have your 2d and 3dmodel. I think this is difenitly a 2d Problem. The 3 cables have the exactly the same cabel or maybe it a 3phase curren width 120deg angle between the phases. see the model sorry for my bad English

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Posted: 10 years ago 2014/06/16 8:09 GMT-4
changed model
changed model


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Posted: 10 years ago 2014/06/16 11:48 GMT-4
2D and 3D models are the same. the only difference is the distance between cables. it is 0.425 m for 2D model and 0.2974 m for 3D model, I forgot to change the distance for 2D model. All cable parameters, i.e. diameters of conductor, insulation, sheath, armour, aluminium wires and jacket are the same. Yeah, I forgot to mention that 3 phase balanced current is going through the cables. So, my question is will the resistances of 2D and 3D model be same? I would like to run 2D simulation because my computer is not powerful enough to handle complex (because of aluminium wires and sheath) 3D models.
Thanks!

Akim
2D and 3D models are the same. the only difference is the distance between cables. it is 0.425 m for 2D model and 0.2974 m for 3D model, I forgot to change the distance for 2D model. All cable parameters, i.e. diameters of conductor, insulation, sheath, armour, aluminium wires and jacket are the same. Yeah, I forgot to mention that 3 phase balanced current is going through the cables. So, my question is will the resistances of 2D and 3D model be same? I would like to run 2D simulation because my computer is not powerful enough to handle complex (because of aluminium wires and sheath) 3D models. Thanks! Akim

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Posted: 10 years ago 2014/06/17 5:14 GMT-4
Dear Akim,
i have solved yout 2d model.

freq = 60Hz
R L1 (mΩ) = 5.73224
R L2 (mΩ) = 5.72243
R L3 (mΩ) = 5.69881
L L1 (nH) = 441.67833
L L2 (nH) = 362.688
L L3 (nH) = 334.39856
Z L1 (mΩ) = 5.73224+0.16651i
Z L2 (mΩ) = 5.72243+0.13673i
Z L3 (mΩ) = 5.69881+0.12607i

hope it help you. The 3d Simulation take a while. Becaus the 3 D Model is not finished and I didnt found any port or coil configuration.

regards Viktor
Dear Akim, i have solved yout 2d model. freq = 60Hz R L1 (mΩ) = 5.73224 R L2 (mΩ) = 5.72243 R L3 (mΩ) = 5.69881 L L1 (nH) = 441.67833 L L2 (nH) = 362.688 L L3 (nH) = 334.39856 Z L1 (mΩ) = 5.73224+0.16651i Z L2 (mΩ) = 5.72243+0.13673i Z L3 (mΩ) = 5.69881+0.12607i hope it help you. The 3d Simulation take a while. Becaus the 3 D Model is not finished and I didnt found any port or coil configuration. regards Viktor


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Posted: 10 years ago 2014/06/17 5:41 GMT-4
ok,
i have some question to your 3d model. Why you use mef for this Problem because, you use only 60Hz. The model is very big and i can not mesh and solve it. My workstation have 256G Ram and 32 Physical Prozessors.
I think for your problem, you need only mf and es in 2d. To calculate RLC Parameters for your cable.

regards Viktor
ok, i have some question to your 3d model. Why you use mef for this Problem because, you use only 60Hz. The model is very big and i can not mesh and solve it. My workstation have 256G Ram and 32 Physical Prozessors. I think for your problem, you need only mf and es in 2d. To calculate RLC Parameters for your cable. regards Viktor

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Posted: 10 years ago 2014/06/18 7:08 GMT-4
Hy dear Viktor Reising!!!

Sorry for interruption in the discussion, actually I am stuck in the problem and can't overcome it from many weeks and also can't get favourable help...
I have almost similar task but a simpler one with some additional task.
I have attached a model with fixed vibrating magnet beam and a circular coil. Principle on which I am working is "Faraday's Law". Voltage value is calculated and I actually need to find:
"The resistance of my circular coil and attach a resistive load equal to coil resistance and secondly obtain the values of Current in Amps and the Maximum Power drawn in Watts".
If Amps and Watts is not possible, kindly suggest for alternate and it will be much beneficial if you kindly do the changing in the attached file.
Kindly reply at your earliest convenience. It will be your great favour for me.
Thanks in advance please and waiting for your kind help.

Regards.
Hy dear Viktor Reising!!! Sorry for interruption in the discussion, actually I am stuck in the problem and can't overcome it from many weeks and also can't get favourable help... I have almost similar task but a simpler one with some additional task. I have attached a model with fixed vibrating magnet beam and a circular coil. Principle on which I am working is "Faraday's Law". Voltage value is calculated and I actually need to find: "The resistance of my circular coil and attach a resistive load equal to coil resistance and secondly obtain the values of Current in Amps and the Maximum Power drawn in Watts". If Amps and Watts is not possible, kindly suggest for alternate and it will be much beneficial if you kindly do the changing in the attached file. Kindly reply at your earliest convenience. It will be your great favour for me. Thanks in advance please and waiting for your kind help. Regards.


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Posted: 10 years ago 2014/06/18 9:31 GMT-4
hi,
to find out the Resistans and Inductance of the coil. Yo can run a parametric run. In the first rund you give the current value for the coil 0[A] and at the seccond 1[A]. If the Simulation is done you can see the Parameter at derived values/ global calculation yo can see the Parameters induced volatge, resistance and so on...

Im loking over to your model in the next days.
regards viktor
hi, to find out the Resistans and Inductance of the coil. Yo can run a parametric run. In the first rund you give the current value for the coil 0[A] and at the seccond 1[A]. If the Simulation is done you can see the Parameter at derived values/ global calculation yo can see the Parameters induced volatge, resistance and so on... Im loking over to your model in the next days. regards viktor

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Posted: 10 years ago 2014/06/18 10:13 GMT-4
Dear Viktor,

I noticed that running simaltion in MF violates current conservation. Therefore, one will have to use either ec or mef ( these two only have current conservation in their equations). But every time I used ec it was giving an error saying "relative residual is greater than relative tolerance". Now I am using mef and I guess it will work.
I appreciate your help, thank you!

Akim
Dear Viktor, I noticed that running simaltion in MF violates current conservation. Therefore, one will have to use either ec or mef ( these two only have current conservation in their equations). But every time I used ec it was giving an error saying "relative residual is greater than relative tolerance". Now I am using mef and I guess it will work. I appreciate your help, thank you! Akim

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Posted: 10 years ago 2014/06/22 2:47 GMT-4
Hy dear Viktor Reising,
I have been trying that but I can find only resistance of coil and confirmed it by R = (rho*L/A) and L = (2*pie*r)*no. of turn but cannot proceed further. Kindly review my model and I hope it will take your very less time. Hoping for a response from you and kindly reply at your earliest convenience.
Thanks in advance.

Regards
Hy dear Viktor Reising, I have been trying that but I can find only resistance of coil and confirmed it by R = (rho*L/A) and L = (2*pie*r)*no. of turn but cannot proceed further. Kindly review my model and I hope it will take your very less time. Hoping for a response from you and kindly reply at your earliest convenience. Thanks in advance. Regards

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Posted: 8 years ago 2016/02/24 14:27 GMT-5

Dear Akim,
i have solved yout 2d model.

freq = 60Hz
R L1 (mΩ) = 5.73224
R L2 (mΩ) = 5.72243
R L3 (mΩ) = 5.69881
L L1 (nH) = 441.67833
L L2 (nH) = 362.688
L L3 (nH) = 334.39856
Z L1 (mΩ) = 5.73224+0.16651i
Z L2 (mΩ) = 5.72243+0.13673i
Z L3 (mΩ) = 5.69881+0.12607i

hope it help you. The 3d Simulation take a while. Becaus the 3 D Model is not finished and I didnt found any port or coil configuration.

regards Viktor

can you explain how can you get these values using the changed model?
[QUOTE] Dear Akim, i have solved yout 2d model. freq = 60Hz R L1 (mΩ) = 5.73224 R L2 (mΩ) = 5.72243 R L3 (mΩ) = 5.69881 L L1 (nH) = 441.67833 L L2 (nH) = 362.688 L L3 (nH) = 334.39856 Z L1 (mΩ) = 5.73224+0.16651i Z L2 (mΩ) = 5.72243+0.13673i Z L3 (mΩ) = 5.69881+0.12607i hope it help you. The 3d Simulation take a while. Becaus the 3 D Model is not finished and I didnt found any port or coil configuration. regards Viktor [/QUOTE] can you explain how can you get these values using the changed model?

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