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In a transformer when you pulse the primary, it induces a magnetic field which induces current on the secondary. The secondary then induces its own magnetic field in opposition to the primary. I think this is what we call BEMF and a manifestation of Lenz law?
Yes.
All of the transformers I have seen are relatively small. Given the speed limit on flux - wouldn't simply having a sufficiently large transformer core along with a sufficiently short pulse on time and dead time, avoid the penalties mentioned above?
Your question brings up in my mind a very interesting answer on getting around Lenz law. I managed to find it in the Sweet-VTA yahoo group, see this link:
http://tech.groups.yahoo.com/group/Sweet-VTA/message/4583 If someone cannot see it, here is the text, first the question, then the answer:
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Really confused about Lenz Law
>
> Hey Yall,
>
> I'm really confused about Lenz's Law. If you place a solid permanent
> magnet through a coil, the coil will produce a magnetic field that
> opposes the magnetic field of the magnet. But, isn't this simply due
> to the fact that magnetic fields flow in a circle from North to South
> pole? Inside the structure of the permanent magnet, magnetic field
> lines flow from South to North, but outside the magnet they loop back
> around and flow from North to South. What gives?
>
> If we placed a coil through a hollow cylindrical permanent magnet,
> wouldn't induction produce a magnetic field that sucks the coil in,
> at least so far as center of the hollow cylinder?
>
> Confused,
> Ed
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Re: Really confused about Lenz Law
Only the imaginary lines of magnetic flux looping around the outside
of a magnet will cut across external conductors and create a current
flow in them which will then have its own opposing magnetic field.
see:
http://micro.magnet.fsu.edu/electromag/java/lenzlaw/index.htmlfor a demo.
But you can get around Lenz's law. If you have a single small loop
inside a conductive cylinder or sphere and the distance from the loop
to the outer conductor wall is X and you apply a microwave signal to
the loop such that a 1/4 wave length of the signal equals X then the
normally opposing magnetic field from the current induced in the outer
conductor will be aiding rather than opposing the magnetic field of
the loop by the time it propagates back to the loop.
Lenz's Law only applies at distances much smaller than the wavelength
of the signal involved. The higher you go in frequency, the more time
delay and so the more phase shift across distances between original
signal and counter EMF signals until an opposing signal becomes an
aiding signal.
George
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Regarding your intention on stepping back from tinkering and starting a study on physics and quantum mechanics: while it is very good to learn on topics like that, you actually do learn while tinkering, so why don't you do both at the same time?
rgds, Gyula