Rotating Magnetic Field's and Inductors.

[MileHigh]

Here you go mate, a second party confirmation with a suggestion how to further boost your results.

Link to video demo: https://www.youtube.com/watch?v=TwKd7UG1Wb8

Enjoy

Luc

I think that you need to review what you mean by the "efficiency of a coil."  Brad has defined it as the average output power from the back spike as compared to the average input power.  In your clip I am not clear on what you mean by "efficiency" nor am I clear on what measurements you are attributing to the claim you are making.  Perhaps the numbers are there in the clip but they are not standing out for me.  Your main point seems to be that a long energizing cycle without a passing rotor magnet inducing a huge amount of EMF in the coil will result in a large amount of current flowing into the coil.  Beyond that I am not really sure what point you are making.

Brad:  You are still not seeing the forest for the trees.  You need to seriously think about the thrust of your argument.

[TinselKoala]

Ditto.

I'm wondering what kind of "efficiency" numbers I'd get from this old thing if I used the same measurement and calculation process that we are calling "efficiency" here.

http://www.youtube.com/watch?v=LfC5cTHtfYY

[MileHigh]

Brad:

I believe that you state in your clip that the rotor has eight magnets alternating north-south-north... facing outwards.  Are you sure about that because your waveforms don't seem to indicate that.

MileHigh

[verpies]

I'm wondering what kind of "efficiency" numbers I'd get

I think that a good efficiency number would be the energy used to energize the coil's circuit (L1 & R1), divided by the energy gained be the capacitor C1, after S1 opens and the "inductive spike" energy is recovered into C1.

...measuring the gain when starting from an empty capacitor, preferably.

[verpies]

Once, I did some math, that calculated the ratio of:

energy stored in an inductance
vs.
energy dissipated in the resistance used to energize this inductance.

...in a simple LR circuit energized by a constant voltage step and I got the formula below, as a function of time (t):

Note, that this formula evaluates to 1 when t = 1.151389*Tau


P.S.
I would appreciate if some math enthusiast could simplify this formula.