Subject: Is there something weird in Counter wound Bifilar Coils ?

Counter-wound bifilar coils (series or parallel connected) wound so that the 
current flows in opposite directions. The magnetic field created by one winding 
is therefore equal and opposite to that created by the other, resulting in a 
net magnetic field of zero. In electrical terms, this means that the self-
inductance of the coil is zero.

a- According to the equation where the energy stored by an inductor, if we feed 
current into a counter-wound bifilar coil, there will not be an energy stored 
in the coil, if so where does the energy in the magnetic field go ?

b- If such a coil is used in a LC (tank) circuit, which interesting results do 
you expect to get ?
(For example if L is equal to zero, does this mean that the resonance frequency 
will be Infinite ?)

c- If this coil is used in an RF antenna, which interesting results do you 
expect to get ? Could you please discuss it ?

Main Reference

http://en.wikipedia.org/wiki/Bifilar_coil

Yours Sincerely

Birol

Re: Is there something weird in Counter wound Bifilar Coils ?