--- In LTspice@..., John Woodgate <jmw@...> wrote:
In message <krbus2+ba2e@...>, dated Sun, 7 Jul 2013, Herbert
<afu@...> writes:
dows anybody have an idea for modelling a inductance with a
permeability in dependency of frequency ??
I want to go right back to the beginning. Because you gave very little
information, people have assumed various things and that can make the
whole thing complex and confusing.
First of all, what frequency range are we in, and what is the material
whose permeability depends on frequency? Secondly, is this material
significantly lossy in that frequency range or not?
For example, if you are looking at nickel-iron at audio frequencies, the
losses are secondary, but if you are looking at ferrites at radio
frequencies, then whether the losses are significant or not depends on
which grade of ferrite you are looking at.
If the losses are NOT significant, then why bother with permeability?
The inductance is proportional to it, so you can just use a table of
inductance against frequency.
If the losses ARE significant, you CAN model as L and R parallel but
both need a table of values against frequency.
Here's an example of a material exhibiting reduced permeability with frequency.
RL
