“Edited material property values are unacceptable for Active Design”

- July 28, 2021 at 2:14 am
  
  Brad_H
  Subscriber
  
  In Ansys Maxwell Electronics 2021 R1, I am trying to edit a material in the Eddy Current Solve mode, but it gives the error: "Edited material property values are unacceptable for Active Design. The data type for the property, permeability, in the material 'NdFeB43' is not supported for the Eddy Current Solution."
  
  I am using a nonlinear B-H curve for permeability, with the BH-field curve chosen as "Normal". Originally, I used "Intrinsic", but I learned the intrinsic B-H curve is not accepted for the Eddy Current Solver. Therefore, I switched to "Normal". Ansys gave the option to automatically convert to the Normal curve from the Intrinsic B-H curve, which I selected.
  
  For the magnetostatic solver, the error messages are more specific. For the Eddy Current Solver, I don't know what to change to get the B-H curve to work. What is wrong with the B-H curve that I specified? I copied the B-H curve data below.
  I should add that this is the B-H curve of a permanent magnet, and I am trying to model its eddy current losses. Thank you in advance.
- July 28, 2021 at 10:17 am
  
  Navya C
  Ansys Employee
  
  The following points need to be satisfied while defining the BH curve.
  ┬ÀFor a Normal BH curve, the slope of the curve cannot be less than that of free space anywhere along the curve.
  ┬ÀThe value of B must increase along the curve. (Please add points in order accordingly)
  ┬ÀThe first data points for B and H must be 0 (zero).
  ┬ÀThe data points representing the BH curve should have enough points for an accurate representation of the curve.20 or more points should be specified with increased representation on the "knee" of the curve.
  
  ┬ÀSince BH operating points in the FEA solution may extend beyond the input BH data set, the BH data set is extrapolated in Maxwell.The slope of the last two user-defined data points is used to extrapolate the BH curve, and thus should be as close to mu0 as possible.
  
  Regards Navya
- August 1, 2021 at 7:25 am
  
  Navya C
  Ansys Employee
  
  HI @Brad_H I didn't notice that you are using permanent magnets in the eddy current solver.
  Permanent magnets cannot be used in eddy current solver. you need to use a Transient solver for your simulation.
  
  Regards Navya