There'something sour here. Way down ...
"Paul Keinanen" wrote in message
...
[snip]
The problem with circuits containing both inductances and capacitances
is that in one kind of reactance, there is a +90 degree phase shift
and the other with -90 degree phase shift. Thus, when these are
combined, they partially cancel each other, producing different
magnitudes and some phase shift between -90 and +90 degrees. If only
the resultant magnitude is used (and the resultant phase is ignored),
this would give the false impression that the inductance changes with
frequency.
I don't quite follow where you are going here. below the self resonant
freq the angle will be +90 (minus a little for what ever resistance is
there).
The rest of this about measuring the energy from DC, I don't think is at all
practical.
[snip] the inductance could be measured in a different way.
... the energy
stored in the inductance is W = I*I*L/2. ...
...cut the DC current...dissipate the energy in some kind of
integrating load across L. Even if there is a significant
capacitance[snip]
...the energy would bounce back
between L and C, but finally it would be dissipated by the external
load. ...
Thus using this measurement method, the value of L would be the same
regardless if C is present or not....
Paul OH3LWR
OK. so then, how do you propose to measure this energy? I don't think
it is practical.
--
Steve N, K,9
d, c. i
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