"Turn Off" a PM... Strategies

[dieter]

Ain't got no axially magnetized ring magnets here, so, what's this twist thing please?


Time compression? Move away? These methods all have the same problem: No matter how fast something is moved, Attraction Force remains the same. Inertia cannot cancel out the field. In fact, turning the field off is the point of interest.


We may consider Victor  Schauberg's theorem about the egg in a stream, that by its shape can neutralize the streams force and float on place, being a forceless, static object.


What if this or something similar works not only in water, but also in a magnetfield?
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[TechStuf]

Ain't got no axially magnetized ring magnets here, so, what's this twist thing please?

Talk is cheap.  But then, so are ring magnets. 




TS

[MarkE]

Dieter, stored energy actuators have canceled permanent magnet flux for many, many years.  Before LASER printers took over the world better quality impact printers used stored energy actuators.  A permanent magnet would act as  the spring.  To release the spring and print a dot, a coil would be energized that canceled the flux from the permanent magnet.

Soldering irons of various different designs have also used the Curie temperature to regulate tip temperature.

The challenge is coming up with a way to turn off and restore the flux in a closed cycle that consumes less energy than can be harvested from the flux change.  No one seems to have found a way to do that.

[TechStuf]

The challenge is coming up with a way to turn off and restore the flux in a closed cycle that consumes less energy than can be harvested from the flux change.

Momentary PM field impingement via counter field EM pulse is hardly "turning off" the field.  Call it "field change" or "field fluctuation", what have you, but it is a misleading generalization to imply that the PM field is being turned off and then restored. 

Examine the work of Howard Johnson at depth.  How many field fluctuations may one decipher in his examples?

And all at little to no cost....

[MarkE]

Momentary PM field impingement via counter field EM pulse is hardly "turning off" the field.  Call it "field change" or "field fluctuation", what have you, but it is a misleading generalization to imply that the PM field is being turned off and then restored. 

Examine the work of Howard Johnson at depth.  How many field fluctuations may one decipher in his examples?

And all at little to no cost....

Techstuf, yes: In precise terms we are adding fields together.  We are manipulating the net flux that passes through a reluctance path we choose.  The same is true with multiple windings on a core whether or not they are layered or multi-filar.  The superimposed fields still appear as one net result to an observer.  The person paying the power bill finds out the difference between a source that "has been turned off" and one where the field has been canceled to some extent with an opposing field.