Learning Forum

[S78MALIK]

I am setting up a system of coils and cores in the eddy current module. I need to calculate the inductance from the matrix solver, but that requires me to add a winding to the matrix parameter. If i add a winding, i need to attach a coil terminal, but i do not want to do that - i would like to input current density as an excitation, since current density from the coil terminals is not the same as i would like. How do i use current density as an excitation but still be able to calculate inductance? Following is my system.

[NKC]

nMay I know, why you do not want to use the standard procedure of assigning coil terminals?nwhat is stopping you or what is the issue you are facing to do so?nWhat advantage do you think you are going to get by assigning the current density?nFor maxwell to calculate the inductance matrix you must define the winding terminals.nnRegardsnNavyan

[S78MALIK]

Hello Navya,nThe reason I don't want to use coil terminals is because as soon as I do that, and provide the number of conductors (number of turns, 1000 for the inner coil and 500 for outer), ANSYS divides the coil rectangular cross sections into 1000 and 500 boxes with equal areas of cross section respectively. Now this area of cross section is different from what I would expect from an 18 AWG copper coil turned around 1000 times for the inner and 500 times for the outer coil. Hence, I get a different current density as that expected from the real life application using the 18 AWG copper wire. Kindly see the following:nArea of cross section of an 18 AWG copper wire = (pi.(1.0237mm)^2)/4nTherefore using a 3 Amp RMS current, current density = 3.645 * 10^6 Amp/m^2 - This is what I want ideally.nBut, what I am getting from coil terminals, when I assign 3 Amps of RMS current is:nnn

[S78MALIK]

Hi @S78MALIK May I know, why you do not want to use the standard procedure of assigning coil terminals?what is stopping you or what is the issue you are facing to do so?What advantage do you think you are going to get by assigning the current density?For maxwell to calculate the inductance matrix you must define the winding terminals.RegardsNavya/forum/discussion/comment/108553#Comment_108553

Hello Navya,nThe reason I don't want to use coil terminals is because as soon as I do that, and provide the number of conductors (number of turns, 1000 for the inner coil and 500 for outer), ANSYS divides the coil rectangular cross sections into 1000 and 500 boxes with equal areas of cross section respectively. Now this area of cross section is different from what I would expect from an 18 AWG copper coil turned around 1000 times for the inner and 500 times for the outer coil. Hence, I get a different current density as that expected from the real life application using the 18 AWG copper wire. Kindly see the following:nArea of cross section of an 18 AWG copper wire = (pi.(1.0237mm)^2)/4nTherefore using a 3 Amp RMS current, current density = 3.645 * 10^6 Amp/m^2 - This is what I want ideally.nBut, what I am getting from coil terminals, when I assign 3 Amps of RMS current is:nnnn