Learning Forum

[Marta Ściubak]

Hi, I am trying to model a 110kV high voltage cable in Maxwell so that when I set a current value in the main conductor, I get the temperature value to which the cable has heated up. More specifically, I want to get the current carrying capacity of the cable.I know that I need to combine the analysis with Icepak. I have created a 3D model of the cable that is 10cm long to reduce the number of mesh elements, which is problematic to generate anyway. I also have a region which, where the 'cut' edges of the cable are, meets the surface of the cable. On the perimeter it is offset 100% from the cable surface. I considered that the eddy current type of solution would be correct. I'm wondering how to set the excitations and boundaries? If I only want to analyse this 10cm slice, how do I ask for the current path and what to set on the "cut" edges of the cable?

[GLUO]

Hi,

Is all current epected at Y direction? If yes, it looks easier to model this in 2D.

GL

[Marta Ściubak]

Yes but I guess to do the analysis in Icepak I need a 3D model?

[GLUO]

Yes, Icepak model has to be in 3D. Please select the two ends of the conductor, assign current to both of them, one goes inside the region and the other goes outside of the region. You can use the default boundary (no additional boundary needed).

GL

[Marta Ściubak]

Thank you for your answer, this is how I solved it.

[Marta Ściubak]

I created an Ansys Maxwell and Icepak Two-Way Coupling analysis for 1cm of cable based on the video:
https://www.youtube.com/watch?v=4MWTGHqRpjk

With the Eddy Current solver, I achieved an ohmic loss of 0.27W and a cable temperature of 65 degrees Celsius. I was not satisfied with this result - it's a bit low. 
I tried an analysis in the Magnestostatic solver, where the ohmic loss was 0.51W - almost double that. Then the cable temperature was 85 degrees Celsius and that was the result I wanted.

Why are these results so different? I don't understand which one is correct and which solver should be used to model this cable. 

I need to ask for an AC current of 1662A and a frequency of 50 Hz. 

I have found several different articles in which the authors use either the Eddy Current or Magnestostatic solver for the AC, hence my doubts and questions.