Re: [FEMM] problems with losses and inductance values

[David Meeker <dmeeker@xxxxxxxx>]

gkoerich@xxxxxxxxxxx wrote:

> Hi!
> I'm having some problems with a solenoid with a variable core model. It's an axisymmetric and time harmonic problem, that uses a very high frequency (112000Hz). 
> The problem is that post-processor results, like resistive losses and inductance (calculated using the field energy equation), are too small compared with the measured values.
> I've tried to vary the mesh size to a very small value and change a little bit the materials property, but up to now nothing about better news.
> Anyone does have an idea? Can I use FEMM to problems with high frequency?
You can use FEMM for high frequencies as long as the frequencies aren't 
so high that displacment currents are important (i.e. the problem is 
still an eddy current problem and not a wave equation problem.

In your case, it sort of sounds like the situation described in 
http://femm.foster-miller.net/pipermail/femm/2001-March/000374.html  In 
AC problems, you have to be careful how you apply the current to the 
solenoid so that you get the results that you want.  This is a bit less 
ambiguous using v4 of the program, which lets you explicitly define 
multi-turn wound regions that behave the "right" way for AC problems.

Dave.