Is this Simulating a Parasitic Transient? - Page 1
Forum section: electronics / beginners

author: Vinyasi
author_rank: Contributor
timestamp: April 25, 2017, 01:43:23 pm
content: https://tinyurl.com/is-this-realistic

author: sokoloff
author_rank: Super Contributor
timestamp: April 25, 2017, 02:10:28 pm
content: Obviously, no.Just a simulation defect (but neat find).

author: Vinyasi
author_rank: Contributor
timestamp: April 25, 2017, 04:23:45 pm
content: I'm sorry. I forgot to provide more information in my post.Is this simulating a parasitic transient?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 26, 2017, 12:36:54 am
content: Turn off "Trapezoidal Approximation" on the capacitors.Tim

author: Vinyasi
author_rank: Contributor
timestamp: April 27, 2017, 04:08:39 am
content: Quote from: T3sl4co1l on April 26, 2017, 12:36:54 amOK. Thanks. I did that and I see it stopped escalating. I don't know what it means. I looked up transient analysis and discovered there are several different methods for analyzing a capacitor. It made it look as though trapezoidal method was inferior.http://www.ecircuitcenter.com/SpiceTopics/Transient%20Analysis/Transient%20Analysis.htmFor my next question, if I remove the 100 nano Ohm resistors, does it make it not realistic on some other principle?http://tinyurl.com/is-this-realistic3Thanks, again.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 27, 2017, 09:29:52 am
content: That it works as well as it does (once "trap" is disabled) is a little impressive.AFAIK, it's not a full SPICE simulation, and you've, seemingly intentionally, built an unrealistic circuit to test those edge cases.If you had chosen sqrt(L*C) to be some multiple of the sample rate, and set up the circuit so that the L, C or both have a dominant loss (R) attached, then the solution would be reasonably well defined. It still might not be physically representative of a circuit made with real components, though.Note that there are three L's per transformer: primary, secondary and mutual. The coupling coefficient seems to be chosen so that Lp * C is too large for the simulation, while LL (leakage inductance, the series equivalent of mutual inductance) is too small for the simulation.Note that opening an ideal switch (I see no reason to believe it's represented as anything else), connected in series with an inductor, or closing one in parallel with a capacitor, implies infinite open-circuit voltage or short-circuit current. Probably this is approximated as a very large delta for one time step.Note that sample rate (time step) is controlled under Options / Other Options.SPICE is a more fully featured simulation environment, but there are plenty of pathological cases it cannot handle. If you built the same circuit in SPICE, you would find it doesn't even begin to start ("error: singular matrix"), because there is no DC ground reference on four(!) nets. (Falstad appears to address this by grounding some nodes implicitly, and not telling you.)Tim

author: Vinyasi
author_rank: Contributor
timestamp: April 27, 2017, 01:02:32 pm
content: I appreciate your response, but fail to have the background to understand much of it ...Quote from: T3sl4co1l on April 27, 2017, 09:29:52 amI chose a one second time step on purpose - by comparison to the prior example [https://tinyurl.com/is-this-realistic] of 500 nano seconds - so that results could manifest rather than appear to be put off for too long to wait around to happen. I didn't know that this is not the case. Did I fail to accelerate the simulation without succeeding at giving it a time step that would erroneously compute values?Quote from: T3sl4co1l on April 27, 2017, 09:29:52 amWo. Way over my head.A dominant loss attached; I have no comprehension of what that means.Quote from: T3sl4co1l on April 27, 2017, 09:29:52 amMy focus was to study fringe cases exhibiting this particular characteristic of escalation; what may be reasonable in assuming is the rarely studied, electrical equivalent contributing to spontaneous combustion of pole transformers, very large loudspeakers at rock concerts, and humans.Quote from: T3sl4co1l on April 27, 2017, 09:29:52 amThis was the default setting. Since it contributed to my intended outcome, I left it alone.Quote from: T3sl4co1l on April 27, 2017, 09:29:52 amDoes this refer to the "Primary Inductance (H)" of the value of 10 on the pair of transformers?{While looking up this value, I realized that the transformers also have a trapezoidal approximation checkbox. So, I unchecked this as well and immediately stopped the escalation. Is this significant?}Quote from: T3sl4co1l on April 27, 2017, 09:29:52 amDoes this mean that the simulation is creating an unrealistically large surge? Since I would expect, and encourage, the creation of surges for the purposes of this study, any surge - no matter how small - would be welcome since I also expect these surges to buildup sooner or later within the confines of the two ultra-low capacitors bounded by the two transformers.Quote from: T3sl4co1l on April 27, 2017, 09:29:52 am

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 27, 2017, 04:51:56 pm
content: Quote from: Vinyasi on April 27, 2017, 01:02:32 pmAh... well suffice it to say, this is the study of dynamical systems: differential equations, difference equations (used in DSP and computer models), polynomial roots, stuff like that. Numerical analysis in particular, using Newton's method (aka trapezoidal approximation), higher order (Runge-Kutta) methods, and more advanced things (that SPICE uses).You should also have a background in circuit analysis: what it means to have current flowing between components, and voltages around them; and how to solve an AC circuit including transformers, dependent sources and all that.In particular, nodal analysis is most often used. This turns the schematic graph into a matrix, and matrix inversion is used to solve A*x = b.(SPICE uses a number of methods to compute this, so that rather than brute-forcing the matrix inversion -- an expensive and numerically unstable operation -- it's done incrementally, to as much accuracy as is required. And if it can't complete the step, it adjusts parameters and tries again: source stepping, GMIN stepping, variable timestep and so on. Advanced topics!)QuoteSome kind of damping -- a resistor causes an oscillating LC circuit to decay towards zero, over time. (This can beproven, using calculus to solve the differential equation exactly. You can then use the proper solution, of simple problems like this, to assess the accuracy and stability of numerical solvers.)Without loss, trapezoidal approximation tends to exhibit growing oscillation over time. (It also tends to produce alternating results:http://www.ece.uidaho.edu/ee/power/ECE524/Lectures/L18/numerosc.pdf)On the other hand, RK2 tends to exhibit slight damping (even when the system is ideal).Real circuits always have resistance, so it's also more realistic to build a model with resistance.QuoteWell you've chosen a pretty terrible simulator to try and prove the existence of such phenomena.Trying to "prove" such a thing, through such means, is rather ponderous to begin with. If you're searching for suspicious (oscillating, diverging) behavior, in a simulated system, you are massively predisposed to finding exactly the unstable edge-cases of the simulator itself -- and absolutely nothing to do with the thing you thought you were searching for in the first place!QuoteNo, none of that happens, nor can happen -- and you've simply found an example of the above.The underlying reasons why those things happen (the things you listed above), is largely to do with thermal overload of materials. To even begin to test that, in a representative way -- you need to build a model that has some representation of temperature, and its effects on the materials used in the circuit. And you need the circuit to be representative of the real system.Pole transformers are connected to the mains supply, so under fault conditions, they can draw megawatts, no sweat. There is absolutely no need to even suspect an exponential divergence here! What's more, the phenomenon fundamentally doesn't exhibit an exponential divergence: the transformer fails internally (usually something like insulationg breakdown, resulting in shorted turns, further heating, and arcing), then consumes power from the supply, limited by resistance and inductance in the path. The consumed power level increases,then levels off. After some cooking, the transformer finally arcs over and blows out, drawing enough current to blow a fuse. The transformer goes out with a bang, and the line voltage stops, returning things to a safe condition.To model this with circuit components, you need a number of state variables (which might be represented by the voltage across a capacitor), and a selection of dependent sources, which are controlled by those variables. The variables, in turn, are affected by the conditions during the event: ambient temperature and heat dissipation, for example.Tim

author: Vinyasi
author_rank: Contributor
timestamp: May 03, 2017, 12:00:47 pm
content: Thanks for the link tothat text on numeric oscillations within simulators. It only helps to exonerate me on what I do by exemplifying what my simulations do. Even Paul Falstad agrees with you. But that doesn't faze me since even a faulty simulator exhibiting parasitic, numerical oscillations of its own trains me to think like a surging parasitic oscillation on the verge of spontaneous combustion.The benefit of learning to manage and harness this "mistaken" venture, is not unlike the benefit of Yoga practice to train me to be a more able bodied person more fit of mind to tackle the big questions of: how does physics explain the creation of energy from energy; the creation of time from time; to give us more of each before it's too late and the circuit dies from lack of both with the help of Noether's theorem excluding conservation of energy from time shifts, ...Loophole Allowance for Free Energy in Conservation of Energy Lawhttps://is.gd/noetherstheorem... also known as: time dilation, phase conjugation, or wave discontinuity with inherent time lags of both magnetic and electric fields so that the net result will be as if time has shifted when the waves get put back together again at the terminus of a cycle of phase conjugation. That is why I use ultra-low capacitors and keep the resistance low between the two transformers so as to accentuate these surges self-materializing from a limited, initial quantity of energy.Losses are what they are - sometimes unavoidable. But I know, now, how to run and operate a "free energy" device that makes more from less ...https://is.gd/aerial_energyA very sophisticated mistake loaded into this faulty simulator using ...https://is.gd/blankcanvasAnd all because I took the time to use a faulty simulator in a faulty manner to study the fault of psychotic breakdowns within the limited context of a faulty, simulated electrical circuit - for they can have such breakdowns just as we can - and from that study figure out what to do about it to make "lemonade from lemons" even if it is just a simulator lacking accuracy or realism.I'm glad I'm not you subject to correct thinking since I'd never be able to do this - nay, I wouldn't have bothered - had I your training. But I also would not have come to feel good about myself had you not helped me see things the way they are. Instead of a mistake making me feel like I had blundered, instead, it makes me feel good.Thank you for your benevolence. Most would have ignored my request.

author: Ian.M
author_rank: Super Contributor
timestamp: May 03, 2017, 12:51:41 pm
content: 'Free Energy' devices are a subset ofPerpetual Motion machinesof the first or second kind.*EVERY* such device to date that has been rigorously investigated has been either proved not to work, or proved to have an external power source or to be using up energy previously stored internally.Extraordinary claims require extraordinary evidenceIf anyone claims that a device produces free energy, the MINIMUM requirements to take it seriously and even consider the possibility of the discovery of new physics, is that it has been demonstrated to output more energy (as total power converted to heat over a time period), while fully enclosed in a hermetically sealed opaque conductive shell, than could possible be stored as chemical energy, (so >25MJ per Kg of device mass), without any detectable ionising radiation, while fully suspended on or from transparent insulating supports, fully inspectable from all sides and under the continuous supervision of a team of reputable independent observers.All circuit simulators assume that Maxwell's equations, and the Lorentz force law are true and sufficient, which complies with the laws of thermodynamics. They will *NEVER* lead you to 'free energy' as their fundamental premise is that 'free energy' is impossible.

author: Vinyasi
author_rank: Contributor
timestamp: May 03, 2017, 01:17:59 pm
content: Yeah. I have to admit. Shifting time within a circuit - getting it convinced that time has sped up or slowed down without recourse to sending it on a rocket ship at nearly the speed of light - is definitely an extraordinary claim.And a faulty simulator is definitely anextraordinary evidence.I am guilty of both.I live for guilt. That's the odyssey of challenging myself with grief, loss and reconciliation through intense study.Thank you Emmy Noether! Thank you Eric Dollard for having inspired me with your LMD module (analog computer of a transmission line in longitudinal magneto-dielectric mode) - even though I have not followed that model with sheer accuracy without modifying it a bit.And thank you imperfect simulators for teaching methe fallacy of taking simulations too seriously- amusing, but ultimately must be tested in the real world for achieving anything other than realistic conclusions ...Spice analysis andits corrected modeling of a spark gap

author: Vinyasi
author_rank: Contributor
timestamp: May 17, 2017, 06:06:26 pm
content: I don't like the extra typing that goes with cross-posting, so I'll keep this short...https://is.gd/simquestI appreciate all of your responses without which I could not formulate any of my own.

author: JPortici
author_rank: Super Contributor
timestamp: May 17, 2017, 06:16:38 pm
content: Quote from: T3sl4co1l on April 27, 2017, 09:29:52 amstill, i like falstad's simulator (and his other applications), i like that it is "realtime", for proof of concepts

author: Vinyasi
author_rank: Contributor
timestamp: May 29, 2017, 06:42:42 am
content: https://is.gd/whateverUwant