Holcomb Energy Systems:Breakthrough technology to the world

[partzman]

Hi Partsman,

Saturation and Hysteresis are somewhat interlinked (sorry but the animated gif linking these won't post). Anyway:

Remant Flux Density (B_r) [Coercivity of material]

From the full Four Quadrant Hysteresis Curve of a ferromagnetic material it can be seen that when the Applied Field (H in amp-turns)
is removed (H = 0) there is still some induction remaining in the material; even though H=0 there is a remant flux density, or B_r as
shown in the full Hysteresis Curve.

This may restrict the full use of the B-H in a pulsed system and may also result in hysteresis losses for AC drive signals. B_r is shown in
the attached Hysteresis Curve from the Arnold Magnetic Technologies - Designing with Thin Guage presentation:

https://www.arnoldmagnetics.com/wp-content/uploads/2017/10/Designing-with-Thin-Guage-presentation-1.pdf

This presentation is worth the read IMHO.

Page/Figure 29 - 1: Hysteresis Curve
> Hysteresis Curve B-sub-r [H: Proj_Steel\Arnold_Magnetics]

One possible fix would be to somehow use the Coil Flyback when the pulse is removed (BEMF quickly falls to a large negative value) to
briefly excite the coil (or a second coil on the pole) thus driving the Pole back, or near to, its initial 0 value (removing or adjusting the
Coercivity). Actual circuit techniques are TBD. Flyback pulse depiction is attached.

This problem - solution requires more analysis and design work.

Kind of a disjointed post but hopefully has some useful information.

SL

This book "Dynamo-electric Machinery: A Manual for Students of Electrotechniques by Sylvanus Phillips Thompson S.Sc., B.A.
London Technical Colledge 1888" goes through the development process of "B-H discovery."

https://books.google.com/books/about/Dynamo_electric_Machinery.html?id=i34AAAAAMAAJ

Chapter XIV. Field-Magnets and Magnatism ... Page 288

https://books.google.com/books?id=i34AAAAAMAAJ&pg=PA288&source=gbs_toc_r&cad=3#v=onepage&q&f=false

Hi SL,

Too bad the animated gifs won't work here. 

In my experience, core remanence due to hysteresis will appear only if there are no gaps in the core material.  Once a gap of a certain magnitude is introduced, the magnitude of remanence will decrease.  There are obvious gaps in the Holcomb magnetic structure so I wonder if remanence will have much of an effect here.

Regards,
Pm

[bistander]

when you talk about LinGen, I always associate this word with lingam.
...

Had to look up definition. I like your humor, but now have undesired mental image.
bi

[bistander]

...
In my experience, core remanence due to hysteresis will appear only if there are no gaps in the core material.  Once a gap of a certain magnitude is introduced, the magnitude of remanence will decrease.  There are obvious gaps in the Holcomb magnetic structure so I wonder if remanence will have much of an effect here.

Regards,
Pm

I agree. This may be a replication flaw with Ariovaldo's cores, ie. no gaps.
bi

[partzman]

For those interested,

Here is a simulation of a moving magnetic unipole across a four pole rotor.  This is done at very high efficiency with only minimal losses due to the current shuttling between the inductors via capacitors.  The bucking sequential switching between the coils produces the nearly constant unipolar field at the core ends.  L1 starts with a current bias of 500ma at t=0us and ends with ~490ma at t=40us.

Regards,
Pm

[bistander]

I will write down a detailed chain of equations for electromagnetic induction. The moment when the circuit is closed is recorded.

Bm = -E:  -E = Bi;   (Bm= Bi) 
...

Hello rakarskiy,
please define Bm, Bi, & -E.
Thanks in advance.
bi