μ is a continuous variable, not a constant, maybe we can have problems at the ends, but this is another story.
yes. but when you draw a loop you limit it to a singular operating parameter. 1 frequency and 1 excitation level at a given DC bias. change any one of these and the loop changes size and rotation. This is your variability. To look at a single point on a minor loop means you are looking at behavior for a much shorter period of time at which point a new loop needs to be drawn taking in account your new excitation level and frequency.
Note: I can't draw the two loops with different inclinations, because my old Tango PCB works on 45º angles, however this is irrelevant, but mind you that, as I said before, coordinate systems are placed arbitrarily, you can rotate which you want, if it makes you happy.
It is the rotation of 1 with relation to the other that is important. If you are saying that your B/H scales can be different for each loop, then this is all pointless since the two loops then have no valid relationship to each other.
dave
yes. but when you draw a loop you limit it to a singular operating parameter. 1 frequency and 1 excitation level at a given DC bias. change any one of these and the loop changes size and rotation. This is your variability. To look at a single point on a minor loop means you are looking at behavior for a much shorter period of time at which point a new loop needs to be drawn taking in account your new excitation level and frequency.
Note: I can't draw the two loops with different inclinations, because my old Tango PCB works on 45º angles, however this is irrelevant, but mind you that, as I said before, coordinate systems are placed arbitrarily, you can rotate which you want, if it makes you happy.
It is the rotation of 1 with relation to the other that is important. If you are saying that your B/H scales can be different for each loop, then this is all pointless since the two loops then have no valid relationship to each other.
dave
Here are two gross oversimplifications of the discussion at hand of two superposed signals one 10X the frequency of the other.
if you actually traced this signal you would not see the 1/10th frequency minor loops but rather a major loop with a set of "squiggles" at 1/10th the frequency. For the sake of this simple experiment lets consider that the 1/10 frequency component essentially sees the major loop as a series of 10 different bias points or XY positons that we could set with DC and then cleanly run the pure 1/10f and get a series of minor loops and it is my belief they would look very similar to this.
Very easy to see
Bac = (Uac x 10⁸) / (√2 π f S Np)
Clearly Bac decreases with an increase of frequency.
While as
Hac = [(4 √2 π Np) / 9 l] iac
Must be maintained its values along the B(H) curve, the result is a less inclined curve, it is as if the curve rotates clockwise.
No, you are still confused, I didn't say that B/H scales can be different for each loop, I said that, due to linear superposition principle I have the freedom to put each coordinate system where I want.
Due to magnetic permeability is well defined, graphs are easy to interpret, so no need to rotate anything.
Oops, typical Tarzan-English misunderstanding, as you did say "line" I understood a curve not a "straight line", on this hemisphere are not synonyms. 😉
Needless to say that I strongly disagree, isn't it?
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I'll side with Bozorth, McLymon, Lee, The EE staff at MIT, and Grossner.
I indeed meant line. You seem to be confusing the slope of a point on a magnetization curve with the slope of a point on a single loop. If you look at the way a magnetization curve is actually derived your error should become apparent.
You cannot interchange the procedures for determining perm from a magnetization curve to that of an individual loop since the magnetization curve is derived from the data from a series of increasing individual loops. (this creates a circular argument)
Maybe you need to read this book
Classical Electrodynamics Third Edition: John David Jackson: 9780471309321: Amazon.com: Books
No, you are confused
A point can't have a slope, a curve does, this is elementary.
And you are doing a mess with magnetization, defined as
B = H + 4π M
You are confusing magnetic hysteresis curve B=f(H) with magnetization curve M=f(H), both has the same shape, but conceptually are not the same thing.
You cannot change Classical Electrodynamics, please follow my advice and read the book, is magnificent. 😉
This kind of reviews make me laugh, to criticize a book, first you must read it, after that you must understand what you did read.
Jackson's is not a computation book at all, just its problems are very hard to solve, and surely its detractors couldn't.
The level of the book is amazing, I can understand its detractors, simply they could not understand the book. 😀
BTW. First edition is better because the use of cgs units, second edition added something to Lorentz covariance, among others, and third edition I have no idea.
Another good book is
Electrodynamics of Continuous Media, Second Edition: Volume 8 (Course of Theoretical Physics): L D Landau, L. P. Pitaevskii, E.M. Lifshitz: 9780750626347: Amazon.com: Books
However focusing on particular topics.
Jackson's is not a computation book at all, just its problems are very hard to solve, and surely its detractors couldn't.
The level of the book is amazing, I can understand its detractors, simply they could not understand the book. 😀
BTW. First edition is better because the use of cgs units, second edition added something to Lorentz covariance, among others, and third edition I have no idea.
Another good book is
Electrodynamics of Continuous Media, Second Edition: Volume 8 (Course of Theoretical Physics): L D Landau, L. P. Pitaevskii, E.M. Lifshitz: 9780750626347: Amazon.com: Books
However focusing on particular topics.
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You obviously have put a lot of effort into it, but imo you somehow managed to turn an already difficult subject into an imcomprehesible one. Thank you for sharing though, but I think I wil just stick with using Yves' application and Patrick Turner's detailed instructions.
hmm, review from a physics PhD from Cornell, publications, actual experience, apparent interest in teaching with a Assistant Professorship - not exactly someone who is just expressing a uninformed sour grapes opinion
Publications
Publications
Please attach the evidence.
If I encourage the physic evidence exposed in this thread I must say that I am a profane guy.
The information is to boring for me specially when I decide to design an Audio transformer. First I will ask to the market. Second I will ask to popilin that made recently a couple of treasures using the poor materials that he could find in the 3th world, In the last position I will ask to AJT. But these are all my excuses. The point is: I try to learn about the deep knowledge of this tread. Each of the exposers tried to demonstrate with mathematics formulas.
Please attach in this thread the information you think is relevant. If popilinging is lying or wrong either if he is a sophist on this era, is no enough to attach bibliography.
Best Regards 😀
If I encourage the physic evidence exposed in this thread I must say that I am a profane guy.
The information is to boring for me specially when I decide to design an Audio transformer. First I will ask to the market. Second I will ask to popilin that made recently a couple of treasures using the poor materials that he could find in the 3th world, In the last position I will ask to AJT. But these are all my excuses. The point is: I try to learn about the deep knowledge of this tread. Each of the exposers tried to demonstrate with mathematics formulas.
Please attach in this thread the information you think is relevant. If popilinging is lying or wrong either if he is a sophist on this era, is no enough to attach bibliography.
Best Regards 😀
I learned a lot from Patrick Turner's web pages, from the RDH3 and RDH4 when they became available for download, from Norman Crowhurst's writings on the internet, postings here by YvesM, cerrem, Bud Purvine, and smoking amp and others...
i have been making my own OPT's since....
i have been making my own OPT's since....
From the beginning you made us know about your displeasure.
I regret that this thread is not for your help. 🙁
The path of knowledge is long, hard and sometimes thankless, good luck with yours. 🙂
Hmm, that confirm my suspicions, not a very impressive curriculum vitae...
I have a friend here who works on Nuclear Magnetic Resonance into a team with a Nobel laureate in Germany, my friend has even more publications, not on the local journal, but on American Journal of Physics.
Where he goes when has a doubt about E&M?
Of course, to Jackson's book, well, he always curses a bit however...😀
Publish or perish is the motor for publishing among scientific community.
A few publications on Optics are not enough to criticize Jackson's book, even less in that pedantic and sarcastic way. 🙄
Jackson's is not only a book on E&M, is THE book on E&M.
John David Jackson (physicist) - Wikipedia, the free encyclopedia
It seems this thread is starting to turn into a battle of the Transformers, the Michael Bay variety.
My dear friend
I put a lot of effort, energy and time on this thread, indeed there are people who want kill me because of their TVs, they are hurry because of the football world championship, so I loose money too.
I'm used to personal/technical attacks on all my threads, can be for my style, or maybe they do not like our flag, but to attack the recommended bibliography, it seems quite absurd, even surreal. 🙄
You know I do not usually lie, I'm neither a sophist, if I were, I would say "I never tell the truth" or "I always lie" 😀
AFAIK all information is correct, if I find an error, I correct it and apologise, if anybody find something wrong, I will grateful, however some people "correct me" with false arguments, and I can't follow with transformers, after all I'm the host, and I must answer, do the contrary wouldn't be polite.
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Displeasure is perhaps too strong a word, I admire your work but unfortuntely I am not able to benefit from your tutorial, but I am sure many other already has or will, so more power to you. 😉
The whole premise seems odd, so let's step back a bit and see what you and/or Juan are saying - are you basically suggesting that the transformers designed with "old" knowledge do not work well? And the new equations can help to address their shortcomings? But isn't it common knowledge that well designed old transformers are the ones most sought after? And many diy'ers lament that the OPTs "are not made like they used to...", no?
It appears that the two of you have reached a deadlock again, surprise...
popilin - could you please just summarize what is new or different with your equations (if any) vis-a-vis the "old" equations. You have posted so much stuff, so a short summary statement would be very helpful.
I apologise if I offended you, but I am too bad with words. 🙂
Hysteresis is defined by a loop, Magnetization by a curve.
The slope of a line tangent to any point on a magnetization curve represents the permeability. The slope of a line tangent to a hysteresis loop does not represent permeability.
In your B=f(h) f is a nonlinear fucntion. How can you apply linear supposition to a non-linear function?
dave
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