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resistive losses and Lubarsky



Dear David Meeker,


Before I start complaining, thanks for your program. It was exactly what I
needed.

One of my objectives was to calculate the resistance at high frequencies.
Message number 49 of the "femm mailing list" got me a bit worried whether or
not the eddy currents were already included in the resistive losses when
using the last FEMM release. In the simulations I did, this component seems
indeed been accounted for. However, in the manual it is stated that:
"Resistive losses; This selection integrates the i^2 R losses due to
currents flowing in the ?z? direction (or theta direction, if you are
evaluating an axisymmetric problem)."

Which sounds to me that eddy currents (that are not flowing in the theta
direction) are not included! Could you please clarify this point?


Second, it seems I found a bug. When evaluating in the FEMM-editor, in the
LUA console window "runpost("temp.fem")", it does run the FEMM-viewer, but
it gives a "run error" (the FEMM-file is attached to this mail.).
With another file, it first states:
"
error: <statement> expected;
last token read: '[' at line 1 in file 'temp.fem'
"
after that, it gives the "run error".
After clicking OK to these messages, the FEMMviewer is working normal.

When using the appropriate button in the FEMM-editor to invoke the
FEMM-viewer, there are no errors for both files.


My third remark. Am I right to think that there is no way for the LUA script
to "switch" from the Lua window in the editor to the Lua window in the
viewer? So a single script can not invoke the design, analyse it and do
calculations on it as well.


And my final remark. The manual states that FEMM can be used fro solving low
frequencies problems. My simulations are run at several hundredths MHz, and
the calculated values (inductance, resistance)seem pretty accurate. Can you
give a general idea what is a high or a low frequency?

Thanks in advance for responding to the remarks.

Henk

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