A3C & X-MAGNETS AND PMF.

[Low-Q]

The picture you posted in your recent post, is a magnet with coil around it. When the magnet pass through the iron core, you will generate electricity through the coil.
This is the same principle as an electric guitar. The pickup is a set of magnets and coils. I don't think this method is reducing feedback. If you happen to have one of these guitars, you can try shortcircuit the coils and see what happens to the sustain on the strings when you play on them. The strings will stop viberating sooner if you short circuit the coils. However, the coils in guitars have rather high impedance, so the back EMF is relatively low. In adittion, the strings are relatively far away from the pickup.


I can do a simple experiment. I have lots of copper foil that has been used in foil inductors for high end speaker crossovers. The foil is uninsolated, so the result will be a "massice copper tube around the magnet.
When this foil is winded around a magnet, and the magnet is approaching an iron core, the magnet will approach the iron core as it was going through syrup. I will post a video if you like.


Vidar

[ageofmagnetizm]

Hi Low-Q,
I've never had a guitars and need (I shall) to learn about the coils in guitars,
once suggesting coil over magnet I had in mind "Anelectropermanent magnet or EPM" at:


https://en.wikipedia.org/wiki/Electropermanent_magnet


often utilizing for lifting purposes and as door-locks, where coils are used for operational
switching of and on magnetic fields of permanent magnet. I still need to work out its practical design
having for now only conceptual set up where moving magnet can generate EMF in one of the coils round
ferromagnetic core - and that coil will be connected to the coil round permanent magnet acting similar to
those coils explained in Wikipedia article (link above). 


It will be very nice if you'll do as you want and post picture and link to videos out here, those conceptual
prototypes presente in first two experimental series are very easy to replicate and test,
though if any information is needed - than I'm eager to help. Following is image of simplest coil with U-Core and bare magnet generating twice more currents than same coil with I-Core inducing by the same magnet.

[Low-Q]

Yes, you get twice the current with the U-core, but also twice the input energy from moving the magnet. The U-core will, as you say, be more efficient, but the same thing happens with an I-core with two different distances to the magnet. The closer you get, the more the induced current in the coil. Increased induction have a cost. Well known in all electric motors.


An important concern regarding measuring input energy and forces, is that many do this by hand. It is impossible to measure with the hand. Specially if the forces are very weak, and you "measure" again with a little more force, it is barely noticable - if noticable at all, but you get higher output readings with the voltmeter. Then people scream "EUREKA!! - I GOT OVER UNITY!" :-)))


Vidar

[ageofmagnetizm]

Hi Low-Q,
here are tree simple arguments and explanations:


1. quo.: ...you get twice the current with the U-core, but also twice the input energy from moving the magnet.
    answ.: twice input of energy happens because that both magnetic poles acting for induction of EMF, while all contemporary generators having magnets with only one magnetic pole moving near one end of a coil. Though force which is necessary for motion of magnet is proportional to its mass not to number of magnetic poles, see - one of magnetic poles do not need to be moved without use... Plus, coils with I-Cores producing Negative Magnetomotive Feedback decelerating inducing magnet, while  coilc with U- C- G- or similar cores producing Zero Magnetomotive Feedback so that magnet moves through ferromagnetic core as easy as it moves through the air. Here comes double of magnetic force and minus Negative Magnetomotive Feedback.
2. quo.:  The closer you get, the more the induced current in the coil.
    answ.: indeed, the width of air gaps is proportional to inducing EMF, and I have compared magnet moving near coil with I-Core with 10mm air gap between them, and same magnet moving near bars of long curved core with same 10mm air gaps between magnetic poles and bars, when widths of air gaps where different (exmpl.: 3mm with I-Core and also 3mm with U-Core) - then voltage readings are higher but proportion remain the same.
3. quo.: An important concern regarding measuring input energy and forces, is that many do this by hand.
    answ.: al measurements are made on the same pendulum having same magnet where pendulum arm is lifted vertically up again stopper then released to free fall without any other input than input producing by gravity pulling pendulum arm down from the exactly same posission with exactly same force causing exactly same velocity... and readings are twice higher..


And I do not "scream "EUREKA!! - I GOT OVER UNITY!" :-)))", it is not overunity but simple innovation of utilization of same known components acting accordingly to known laws but generating electricity in more efficient manner because of novel methods and constructions.
Once I'm posting here it is because that energy of moving whole magnet do not need to be wasted by utilization of just one magnetic pole and there many variants of development which could be interesting for guests and users of this group.


Take it easy, and preview your post before clicking on post button. This will save you from reading your post with filling of shame. No need to worry, just ask and I'll explain.

[ageofmagnetizm]

One more utility design of simple MEG has been published at:


https://sites.google.com/site/ageofmagnetizm/home/magnetomechanics/simple-megs-and-semi-permanent-electromagnet


New design has stator with H-Core with many coils on it.
Please make your suggestion which of nine published designs should be preferred for manufacturing prototypes.