Magnetic Compression Study" by Cyril Smith

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Author Topic: Magnetic Compression Study" by Cyril Smith (Read 32018 times)

Smudge	Magnetic Compression Study" by Cyril Smith « on: 2016-09-27, 15:19:14 »
Group: Professor Hero Member Posts: 1856	Here is my paper on the Gunderson-Smith Effect. Looking back over my files I have more material on this subject. If everyone agrees I will not clutter this thread but will start a new one devoted to using ferro-magnetic resonance as a means to obtaining OU. Smudge ------------------------ The Gunderson Smith Effect.pdf (120.45 kB - downloaded 331 times.)

Smudge	Re: Magnetic Compression Study" by Cyril Smith « Reply #1 on: 2016-09-27, 19:29:12 »
Group: Professor Hero Member Posts: 1856	Woops, I made a mistake in the table with the energy gain for PE22 material. Here is the corrected paper ------------------------ The Gunderson Smith Effect.pdf (120.51 kB - downloaded 333 times.)

Peterae	Re: Magnetic Compression Study" by Cyril Smith « Reply #2 on: 2016-09-27, 20:31:37 »
Group: Administrator Hero Member Posts: 3867	Hi Smudge Thanks for your hard work, the paper is very interesting, how hard would it be to setup to test a core material 4D2, what is needed in the way of electronics, if it's a fairly easy setup i would give it a go, i can start a dedicated thread if you wish. Regards Peter

verpies	Re: Magnetic Compression Study" by Cyril Smith « Reply #3 on: 2016-09-27, 22:56:54 »
Group: Professor Hero Member Posts: 3359	Quote from: Smudge on 2016-09-27, 15:19:14 Here is my paper on the Gunderson-Smith Effect. Looking back over my files I have more material on this subject. If everyone agrees I will not clutter this thread but will start a new one devoted to using ferro-magnetic resonance as a means to obtaining OU. Smudge I will disagree since I have the impression that you are like my girlfriend who is such a good dancer that nobody wants to ask her to dance at a party. Quote from: Smudge The second possibility relates to the frequency response of the core material where its permeability can have different values for different rates-of-change of flux. You forgot to account for the well known behavior of a coil, which responds to an increasing permeability (decreasing reluctance) of the magnetic circuit with a decrease of the current flowing through its windings. To be more precise, I mean the response of an energized, shorted ideal solenoid coil, which is subjected to a changing permeability/reluctance as in a scenario in which a soft ferrite slug is being inserted inside it. Note that the coil's current decreases as the ferrite slug approaches the coil. Quote from: Smudge ... one being the possibility that energy could be stored in the compression of the Mylar film situated between the two core halves, and that mass inertia might play its part in slowing down the change in compression when the flux changes value. During the slow flux change between secondary interrupts the compression would follow the flux, but in the fast flux change period the core faces would not move hence creating an imbalance between the magnetic energy and the stored compression energy. After exploring this in some detail it has been found that this imbalance does not lead to over-unity. 1) How did you determine that? 2) Did you ever prove the 3^rd possibility, that the kinetic energy gained by an approaching soft ferrite slug (or approaching ferrite core halves) is not greater than the difference between ½L_MINi_MAX² - ½L_MAXi_MIN² without using the CoE law ? ( notation is according to this article ) « Last Edit: 2016-09-27, 23:28:37 by verpies »

ion	Re: Magnetic Compression Study" by Cyril Smith « Reply #4 on: 2016-09-28, 00:11:41 »
Group: Elite Hero Member Posts: 3537 It's turtles all the way down	First, thanks greatly to Cyril for his good work on this introductory paper. I would agree with Cyril's intention at the end of the paper that a new thread be started. May I suggest "Magnetic Compression Studies" as a title for the thread? I would not agree that an "effect" be named an "effect", before it is proven by replication that "the effect" actually exists. In other words an "effect" should be observable and testable by anyone who sets up the experiment, based on a full disclosure of the details of the experiment by the party that first notices the "effect" In light of the fact that Graham, although given ample time to fully disclose either to this community or elsewhere, has not done so, I believe the title should be changed to something more generic e.g. "Magnetic Compression Study" by Cyril Smith. I use the word "study" because that is exactly what it should be. A hypothesis is presented and it should be studied to see if an "effect" can be demonstrated and observed in the lab and then replicated, which could thus lead to a "theory". When it is determined that such a study leads to an novel "effect", then IMO, it should be first named "The Smith Effect" after Cyril who has hypothesized and identified and freely given the necessary structure for replication, without reserve. When it is determined that the Gunderson transformer and associated circuitry is indeed operating according to Cyril's named effect, then perhaps Gunderson's name can be included in the title or perhaps in the text, but again, only if he fully co-operates with Cyril and / or the community with full disclosure and participation. It is sad to see that because of Gunderson's non-cooprative stance, much guesswork has ensued and time has been wasted, when everything could have moved along much more quickly. This is not the way of science. There is a somwhat a danger in posting a paper with such a title, because there are those entities that are poised looking for something exactly like this to buttress the next commercial release, which will probably be named " Beyond The Secrets of the Implosion Transformer" .You can be certain this paper and anything that follows will be scooped up by certain for profit entities and used in future commercial releases as a "proof positive", even though such proof has not yet been established, and worse yet, even if the hypothesis fails it will be probably be given a "pass" by those entities. I have given this a lot of thought and believe that we should work the science of discovery carefully, and not skip the proper steps. FWIW, do as you will. Kind Regards ION « Last Edit: 2016-09-28, 12:34:53 by ION » --------------------------- "Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy

TinMan	Re: Magnetic Compression Study" by Cyril Smith « Reply #5 on: 2016-09-28, 00:35:50 »
Group: Elite Experimentalist Hero Member Posts: 4608	Quote from: ION on 2016-09-28, 00:11:41 First, thanks greatly to Cyril for his good work on this introductory paper. I would agree with Cyril's intention at the end of the paper that a new thread be started. May I suggest "Magnetic Compression Studies" as a title for the thread? I would not agree that an "effect" be named an "effect", before it is proven by replication that "the effect" actually exists. In other words an "effect" should be observable and testable by anyone who sets up the experiment, based on a full disclosure of the details of the experiment by the party that first notices the "effect" In light of the fact that Graham, although given ample time to fully disclose either to this community or elsewhere, has not done so, I believe the title should be changed to something more generic e.g. "Magnetic Compression Study" by Cyril Smith. I use the word "study" because that is exactly what it should be. A hypothesis is presented and it should be studied to see if an "effect" can be demonstrated and observed in the lab and then replicated, which could thus lead to a "theory". When it is determined that such a study leads to an novel "effect", then IMO, it should be first named "The Smith Effect" after Cyril who has hypothesized and identified and freely given the necessary structure for replication, without reserve. When it is determined that the Gunderson transformer and associated circuitry is indeed operating according to Cyril's named effect, then perhaps Gunderson's name can be included in the title, but again, only if he fully co-operates with Cyril and / or the community with full disclosure and participation. I have given this a lot of thought and believe that we should work the science of discovery carefully, and not skip the proper steps. FWIW, do as you will. Kind Regards ION I agree ION,and i would be most interested in this,as i have carried out a few experiments in this area,based on a paper verpies once sent to me. Yes,please start a dedicated thread on the subject matter Brad « Last Edit: 2016-09-28, 14:24:30 by TinMan » --------------------------- Never let your schooling get in the way of your education.

Peterae	Re: Magnetic Compression Study" by Cyril Smith « Reply #6 on: 2016-09-28, 08:09:54 »
Group: Administrator Hero Member Posts: 3867	Hi ION I agree totally, i have left this in the Buzz thread for the moment but split it from the original Gunderson thread, lets see if we can see an effect first. Regards Peter

Smudge	Re: Magnetic Compression Study" by Cyril Smith « Reply #7 on: 2016-09-28, 11:45:03 »
Group: Professor Hero Member Posts: 1856	Quote from: verpies on 2016-09-27, 22:56:54 You forgot to account for the well known behavior of a coil, which responds to an increasing permeability (decreasing reluctance) of the magnetic circuit with a decrease of the current flowing through its windings. To be more precise, I mean the response of an energized, shorted ideal solenoid coil, which is subjected to a changing permeability/reluctance as in a scenario in which a soft ferrite slug is being inserted inside it. Note that the coil's current decreases as the ferrite slug approaches the coil. I think you have missed the point here. This is not something that is going on outside the core (like your moving slug) but something inside the core. It is not an absolute permeability change, it is an incremental permeability change. The absolute permeability doesn't suddenly change when going from charge to discharge, so there is no change of flux at that point in time. But the incremental permeability is different because the domain wall resonance comes into play, so the flux change during the discharge (for a given change of current) is greater than that during the charge. And that creates the CW loop. Quote 1) How did you determine that? Considering a gap where the fringe effects are negligible, the formula for pressure at the mating faces is identical to the formula for magnetic energy density within the gap. That equivalence mean that any mechanical work done when the gap changes exactly matches the change in magnetic energy. And it is that energy that the usual Li²/2 relates to. It is not necessary to invoke CoE. Whether whoever derived the pressure formula used CoE to get it I know not. If in reality the pressure differs from that formula I am of the opinion that the difference would be very small, so any gain in COP would be lost due to the usual losses. Quote 2) Did you ever prove the 3^rd possibility, that the kinetic energy gained by an approaching soft ferrite slug (or approaching ferrite core halves) is not greater than the difference between ½L_MINi_MAX² - ½L_MAXi_MIN² without using the CoE law ? ( notation is according to this article ) I think my answer above covers that Smudge

verpies	Re: Magnetic Compression Study" by Cyril Smith « Reply #8 on: 2016-09-28, 12:40:44 »
Group: Professor Hero Member Posts: 3359	Quote from: Smudge on 2016-09-28, 11:45:03 I think you have missed the point here. This is not something that is going on outside the core (like your moving slug) but something inside the core. I think you have missed the point that the slug IS the core and it is moving into the INSIDE of the coil. Quote from: Smudge on 2016-09-28, 11:45:03 It is not an absolute permeability change, it is an incremental permeability change. I know the difference between absolute permeability and differential permeability, but what of that difference? The moving slug affects the reluctance of the magnetic circuit absolutely and differentially, all the same. Quote from: Smudge on 2016-09-28, 11:45:03 The absolute permeability doesn't suddenly change when going from charge to discharge, so there is no change of flux at that point in time. There wouldn't be any flux change even if the absolute permeability changed inside an energized shorted ideal coil. So I just don't see the point you are trying to make about the lack of change of flux being caused by the lack of absolute permeability change. Quote from: Smudge on 2016-09-28, 11:45:03 But the incremental permeability is different because the domain wall resonance comes into play, so the flux change during the discharge (for a given change of current) is greater than that during the charge. And that creates the CW loop. I understand the CW BH loop but in the end the charge and discharge energies are related to the absolute permeability which affects the inductance in the ½Li² relation, which in turn affects the current waveforms during charge and discharge. Quote from: Smudge on 2016-09-28, 11:45:03 Considering a gap where the fringe effects are negligible, the formula for pressure at the mating faces is identical to the formula for magnetic energy density within the gap. Yes, the fringing is negligible but pressure/force is not the same as energy, and energy density is customarily calculated from the integration of that force over the thickness of that gap and the gap's area and using the CoE. Quote from: Smudge on 2016-09-28, 11:45:03 That equivalence mean that any mechanical work done when the gap changes exactly matches the change in magnetic energy. In the gap, but not inside the ferrite. What about the energy represented by the alignment/magnetization of the soft ferrite's domains? Alas, that energy can be recovered as the ferrite relaxes. « Last Edit: 2016-10-03, 12:35:51 by verpies »

Smudge	Re: Magnetic Compression Study" by Cyril Smith « Reply #9 on: 2016-09-28, 16:50:38 »
Group: Professor Hero Member Posts: 1856	Quote from: verpies on 2016-09-28, 12:40:44 I think you have missed the point that the slug IS the core and it is moving into the INSIDE of the coil. I'm sorry, I thought you were talking about a slug moving into an air gap in the core. I was not looking into slugs moving into coils, I was looking into variable air gaps. I don't see the relevance of your original question in relation to variable air gaps. Quote I know the difference between absolute permeability and differential permeability, but what of that difference? The moving slug affects the reluctance of the magnetic circuit absolutely and differentially, all the same. I wasn't looking at moving slugs. Quote There wouldn't be any flux change even if the absolute permeability changed inside an energized shorted ideal coil. So I just don't see the point you are trying to make about the lack of change of flux being caused by the lack of absolute permeability change. Here your original question related to the change of permeability between slow charge and fast discharge where you introduced the effect of a moving slug changing the permeability. The point I am making is that the change is not due to a moving slug. The permeability doesn't change at the point where the discharge starts. The permeability is a dynamic thing relying on rate-of-change of current. Quote I understand the CW BH loop but in the end the charge and discharge energies are related to the absolute permeability which affects the inductance in the ½Li2 relation, which in turn affects the current waveforms during charge and discharge. I disagree that those energies relate to the absolute permeability. The voltage developed (hence also energy) relates to the differential permeability. I can imagine a non-linear core biased at some point by the use of a PM, then a coil being charged and discharged where the flux changes over a small region of the BH curve. The coil is not aware of the PM bias and its charge and discharge is related to the differential permeability at that bias point. The absolute permeability doesn't come into it. Quote Yes, the fringing is negligible but pressure/force is not the same as energy, and energy density is customarily calculated from the integration of that force over the thickness of that gap and the gap's area and using the CoE. Well perhaps that answers my question, our recognized formula are derived using CoE. Then no wonder we can't get OU from theory. I had thought that magnetic energy density B²/2*mu was derived some other way. Quote In the gap, but not inside the ferrite. What about the energy represented by the alignment/magnetization of the soft ferrite's domains? Alas, that energy can be recovered as the ferrite relaxes. My analysis assumed ferrite permeability sufficiently high that the (conventional) energy internal to the ferrite was negligible. Smudge

Smudge	Re: Magnetic Compression Study" by Cyril Smith « Reply #10 on: 2016-09-28, 16:58:50 »
Group: Professor Hero Member Posts: 1856	Here is something to think about regarding soft materials. Smudge ------------------------ Some musings on magnetization3.pdf (20.79 kB - downloaded 247 times.)

Peterae	Re: Magnetic Compression Study" by Cyril Smith « Reply #11 on: 2016-09-28, 18:21:41 »
Group: Administrator Hero Member Posts: 3867	Another interesting paper thanks Smudge. So we need to drive a core at a low frequency and extract the energy at the cores ferromagnetic resonant frequency or a multiple of harmonic of the low frequency. So the hardest thing i can see is finding the cores ferromagnetic resonant frequency. If we tune the primary as a tuned LC and tune the secondary as a higher harmonic tuned LC.

Smudge	Re: Magnetic Compression Study" by Cyril Smith « Reply #12 on: 2016-09-28, 19:06:55 »
Group: Professor Hero Member Posts: 1856	Quote from: Peterae on 2016-09-28, 18:21:41 Another interesting paper thanks Smudge. So we need to drive a core at a low frequency and extract the energy at the cores ferromagnetic resonant frequency or a multiple of harmonic of the low frequency. So the hardest thing i can see is finding the cores ferromagnetic resonant frequency. If we tune the primary as a tuned LC and tune the secondary as a higher harmonic tuned LC. Don't bother with making a transformer, just use a single coil. Used a non-gapped core such as a ring core if possible. Then measure its inductance against frequency and at resonance the inductance should be greater than at non-resonance. The published data sheet will show the frequency so you should know where to look. Then the idea is to charge the inductor slowly then resonantly discharge it quickly at the ferromagnetic resonant frequency, not a harmonic of the low frequency. So you have a simple charging circuit that need not be resonant, then to discharge it you switch the inductor onto a capacitor of the appropriate value to resonate at the known frequency, allow the capacitor to charge over half a cycle then switch the capacitor onto a load R. Keep doing that at some rep rate. Smudge

Smudge	Re: Magnetic Compression Study" by Cyril Smith « Reply #13 on: 2016-09-28, 19:39:19 »
Group: Professor Hero Member Posts: 1856	Here is a paper written some time ago on using the slow charge fast discharge scheme. This looks at resonant charging at 100KHz by switching a charged capacitor onto the inductor, that capacitor being two capacitors in parallel. At the point where all the energy is now stored in the inductor, where the capaciitor voltage has fallen to zero, one of the capacitors is removed leaving only one there, and that one resonates with the changed inductance value at the ferromagnetic resonant frequency. The energy stored in the inductor now swings back into the reduced capacitance, and when the current reaches zero the capacitor is disconnected to then be switched onto a load. The formula for COP is derived using published complex permeability data. Smudge ------------------------ On using Complex Permeability Resonance to get OU.pdf (143.82 kB - downloaded 246 times.)

Peterae	Re: Magnetic Compression Study" by Cyril Smith « Reply #14 on: 2016-09-28, 22:06:12 »
Group: Administrator Hero Member Posts: 3867	That is fantastic work Smudge and this test is exactly the type of experiment i really enjoy doing. I have two fets SiC 1700 V, 5A and two fets SiC 1200 V, 10A sitting in the work shop waiting for a project so we could probably up the voltage somewhat, hopefully they would be ok to switch capacitors in circuit. I need to think about the driving circuit but should be easy enough. So to walk myself through the functioning schematic the way i see it. we switch the psu onto the capacitors and charge to 10v. Isolate the power supply and switch the inductor across the 2 capacitors in parallel, when the voltage across the capacitors nears 0V we isolate the larger capacitor leaving the smaller capacitor connected across the inductor. You say in quarter of a cycle we reach 124.1V across the smaller capacitor but surely we are on the negative quarter cycle so would be at -124.1V if so my SICs have body diodes and thats not good for how i was going to use them for switching the ground legs of the psu and caps. OK more thought required.

ion	Re: Magnetic Compression Study" by Cyril Smith « Reply #15 on: 2016-09-28, 22:51:26 »
Group: Elite Hero Member Posts: 3537 It's turtles all the way down	Thanks for those three latest papers, Smudge. Now, I wonder if this could be simulated in LTSpice by an expression which changes the inductor's model at the appropriate moment in the cycle. Any thoughts, partzman, Smudge? Regards, ION --------------------------- "Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy

partzman	Re: Magnetic Compression Study" by Cyril Smith « Reply #16 on: 2016-09-29, 00:41:49 »
Group: Experimentalist Hero Member Posts: 1671	Quote from: ION on 2016-09-28, 22:51:26 Thanks for those three latest papers, Smudge. Now, I wonder if this could be simulated in LTSpice by an expression which changes the inductor's model at the appropriate moment in the cycle. Any thoughts, partzman, Smudge? Regards, ION ION, IMO, it is doable in simulation using gyrator-capacitance modeling. I am looking at Magnetics "P" material because I have it on hand and it has an initial u'=2500 up to 100kHz and peaks with a u' = 3400 at 500kHz so the ratio of change is close to the PE22 material with a narrower frequency spread. I plan to use Smudge's math to calculate the possible COP and will post when finished. I've attached a paper from Magnetics that contains curve fit equations for their materials that would be used to define the nonlinear capacitance to represent the nonlinear core permeability in the G-C model. The core loss would then be modeled with a nonlinear resistor. The problem I've found in doing this type of nonlinear modeling is difficulty with convergence. IOW, the sim "sticks" at certain points during the simulation when it is having difficulty resolving internal calculations and may or may not recover. pm edit ------------------------ FC-S7 Curve Fit Equations for Ferrite Materials.pdf (117.65 kB - downloaded 223 times.)

ion	Re: Magnetic Compression Study" by Cyril Smith « Reply #17 on: 2016-09-29, 01:02:18 »
Group: Elite Hero Member Posts: 3537 It's turtles all the way down	partzman Thanks for the Magnetics paper on curve fitting. I kind of thought you would have a solution to the simulation of Smudge's ideas. Is there a sim out there that would help me learn more about the use of gyrators? I'll do some searching on the subject. You and Smudge are keeping some of us very busy (in a good way). Thanks again Regard ION --------------------------- "Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy

Smudge	Re: Magnetic Compression Study" by Cyril Smith « Reply #18 on: 2016-09-29, 08:49:58 »
Group: Professor Hero Member Posts: 1856	My interest would be modelling in the magnetic domain. Whereas the normal magnetic domain model for an inductor having a closed magnetic circuit (i.e. a coil wound on a ring core) would be an mmf generator of Ni ampere-turns connected across the classical reluctance of the core (l/(murmunoughtA) my model would differ from that. I would use two mmf generators in series connected across the reluctance of the air space occupied by the core. One generator would have the value Ni and the other would have the value chi*Ni where chi is the magnetic susceptibility. Then the reluctance of the air core remains constant and it is the value of chi that exhibits the resonance, that changes value with frequency. If using Spice to model the magnetic domain the frequency variation applies to the "voltage" generator and it is quite simple to model that. The attached pdf could help in turning published complex permeability data into the frequency variations of chi. Smudge ------------------------ complex permeability.pdf (64.43 kB - downloaded 240 times.)

Smudge	Re: Magnetic Compression Study" by Cyril Smith « Reply #19 on: 2016-09-29, 09:29:42 »
Group: Professor Hero Member Posts: 1856	Here is another paper that introduces the magnetic domain modelling where the susceptibility chi has the resonance. Smudge ------------------------ Using change of permeability.pdf (30.86 kB - downloaded 229 times.)

partzman	Re: Magnetic Compression Study" by Cyril Smith « Reply #20 on: 2016-09-29, 15:01:52 »
Group: Experimentalist Hero Member Posts: 1671	Quote from: ION on 2016-09-29, 01:02:18 partzman Thanks for the Magnetics paper on curve fitting. I kind of thought you would have a solution to the simulation of Smudge's ideas. Is there a sim out there that would help me learn more about the use of gyrators? I'll do some searching on the subject. You and Smudge are keeping some of us very busy (in a good way). Thanks again Regard ION ION, I've attached some papers that I used to gain an understanding of G-C simulation. There are some ready made gyrator models in the files of the LtSpice forum that one can play with but I chose to make my own model with external variables like DCR and number of turns. I started using the H source but would recommend the B source. There are two B sources available and those are Bv and Bi. Basically, a Bv source is a device that produces a voltage across it's terminals that is dependent on any math function that is included in the help file listing on the sources. Bi works the same but as a current source. In general, a gyrator can be built with two cross coupled Bv sources where one is used as a port for the electrical inputs to a winding whereby the other one is used to represent the magnetic circuit for the same winding. In this manner, any type and/or size of core material in any configuration may be modeled with reasonable accuracy. For example, in Graham's device where the upper U core is high perm while the lower U core is a lower perm material presents a unique situation which can be modeled with the G-C gyrator. I hope this is of some help. pm ------------------------ Gyrator capacitor modeling.pdf (590.5 kB - downloaded 468 times.) Lumped Equivalent Circuits of Magnetic Components_The Gyrator Capacitor Approach.pdf (885.38 kB - downloaded 261 times.) Gyrator-capacitor Simulation Model of Nonlinear Core.pdf (827.86 kB - downloaded 357 times.)

partzman	Re: Magnetic Compression Study" by Cyril Smith « Reply #21 on: 2016-09-29, 15:07:00 »
Group: Experimentalist Hero Member Posts: 1671	Quote from: Smudge on 2016-09-29, 09:29:42 Here is another paper that introduces the magnetic domain modelling where the susceptibility chi has the resonance. Smudge Smudge, Thanks for posting these papers. I'm personally a little slow on getting up to speed with mathematical concepts so lots of study is in order. pm

Smudge	Re: Magnetic Compression Study" by Cyril Smith « Reply #22 on: 2016-09-29, 16:15:13 »
Group: Professor Hero Member Posts: 1856	Just found this paper hidden among my files. It may help in understanding just what complex permeability means and how it effects circuits. It tells how to use published complex permeability data to determine inductance and effective loss resistance. And how to determine the complex permeability from measurements. Smudge ------------------------ Evaluation and Measurement of Complex Permeability.pdf (55.07 kB - downloaded 230 times.)

ion	Re: Magnetic Compression Study" by Cyril Smith « Reply #23 on: 2016-09-29, 16:22:12 »
Group: Elite Hero Member Posts: 3537 It's turtles all the way down	Quote from: partzman on 2016-09-29, 15:01:52 ION, I've attached some papers that I used to gain an understanding of G-C simulation. There are some ready made gyrator models in the files of the LtSpice forum that one can play with but I chose to make my own model with external variables like DCR and number of turns. I started using the H source but would recommend the B source. There are two B sources available and those are Bv and Bi. Basically, a Bv source is a device that produces a voltage across it's terminals that is dependent on any math function that is included in the help file listing on the sources. Bi works the same but as a current source. In general, a gyrator can be built with two cross coupled Bv sources where one is used as a port for the electrical inputs to a winding whereby the other one is used to represent the magnetic circuit for the same winding. In this manner, any type and/or size of core material in any configuration may be modeled with reasonable accuracy. For example, in Graham's device where the upper U core is high perm while the lower U core is a lower perm material presents a unique situation which can be modeled with the G-C gyrator. I hope this is of some help. pm Hi partzman Thanks much for the papers. I have been doing some research on gyrators and my fuzzy brain now realizes I built one (an pseudo inductance simulator) out of the National Semiconductor catalog back in 1977 or thereabouts. With age I can now claim to have forgotten more than I presently know. The ramifications are that I will arrive at a point where I know nothing and have forgotten everything. It amazes me that Smudge and yourself can keep the ol' biocomputer working so well. Improved refresh clock cycles perhaps? Regards, ION --------------------------- "Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy

partzman	Re: Magnetic Compression Study" by Cyril Smith « Reply #24 on: 2016-09-29, 17:17:48 »
Group: Experimentalist Hero Member Posts: 1671	After setting up the variables in Mathcad and solving for the low frequency resonance capacitor Cl in equation (4) in Smudge's paper "On using Complex Permeability Resonance to get OU", it becomes obvious that the lower the ui, Fl, and Lair, the more realistic the value of Cl will be. In my example, with Lair = 250uh, Fl = 100kHz, and ui = 2500, Cl = 4.053pfd. Does this sound right to you Smudge? pm

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