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Author Topic: Joule Thief 101  (Read 926706 times)

MileHigh

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Re: Joule Thief 101
« Reply #2400 on: May 11, 2016, 07:02:25 PM »
I have never personally believed you to be absolutely wrong, I just personally disagree with the logic behind 0 resistance in the real world so far. And so far, I don't see how any math or sims can provide us the absolute answer. That has absolutely nothing to do with the potential faith I can put into you knowing what you're talking about regarding any other scenario regarding an R value that is not absolute 0. If we were all discussing an R value that is ANYTHING other than 0, this would not be so frustrating.

So I don't see why you feel the need to get offended or lose patience.  It's not like anyone is saying, "Oh wow, you ACTUALLY think that? you must have no idea what you're doing in any other equations then"..

It's more like, "wait.. are you ACTUALLY saying you know for sure what would happen in the real world with your 5h R=0 inductor?"  this is because, I can't really tell to be honest, but it seems like you are saying that with the confidence that it is more than hypothesis..

you said " Just believing that you are right for whatever strange reason does not make it right."

Isn't this what the argument is really about?

It is really not such a huge mental leap to imagine an inductor with zero resistance.  Can you imagine an inductor with 0.000001 ohms resistance?  Can you imagine an internal combustion engine where the main crankshaft bearings are replaced by "magic" bearings having no resistance?

I told Brad to go ahead and try to answer the question by adding a 0.000001 ohm resistor to the inductor to "fix the problem" and he passed on that.  So zero ohms or 0.000001 ohms, Brad was incapable of answering the question.  Progress is currently running at about one millimeter per day.

Anybody can open up a book or do some Googling.  Every single student that takes an electronics course ends up perfectly understanding ideal capacitors and ideal inductors. Think of the ICE as a very similar hypothetical example.

Sometimes things seem to be tough and you have to learn then.  That's all there is to it, you have to learn them and master them.  Repeatedly saying "the current goes to infinity because the resistance is zero" is ridiculous, you absolutely must learn what inductance is if you are going to progress and get more out of your experimenting.  If you truly knew what inductance really is, you would scoff at the notion that the current goes to infinity in an ideal inductor.

Magneticitist

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Re: Joule Thief 101
« Reply #2401 on: May 11, 2016, 07:24:10 PM »
It is really not such a huge mental leap to imagine an inductor with zero resistance.  Can you imagine an inductor with 0.000001 ohms resistance?  Can you imagine an internal combustion engine where the main crankshaft bearings are replaced by "magic" bearings having no resistance?

I told Brad to go ahead and try to answer the question by adding a 0.000001 ohm resistor to the inductor to "fix the problem" and he passed on that.  So zero ohms or 0.000001 ohms, Brad was incapable of answering the question.  Progress is currently running at about one millimeter per day.

Anybody can open up a book or do some Googling.  Every single student that takes an electronics course ends up perfectly understanding ideal capacitors and ideal inductors. Think of the ICE as a very similar hypothetical example.

Sometimes things seem to be tough and you have to learn then.  That's all there is to it, you have to learn them and master them.  Repeatedly saying "the current goes to infinity because the resistance is zero" is ridiculous, you absolutely must learn what inductance is if you are going to progress and get more out of your experimenting.  If you truly knew what inductance really is, you would scoff at the notion that the current goes to infinity in an ideal inductor.

It's not much of a mental leap when we look at it entirely in experimental terms. But it actually becomes a very interesting discussion and a quite a "thinker" when you really get to the meat of the 0 resistance argument in the real world. Maybe not to you, but to someone like me, it is an intriguing area of circuit theory to think about because it potentially has to do with the very nature
of how things 'actually work'. I understand by simply thinking into any further than you personally would like to is almost an insult to the established way of things but I don't feel you should see it that way.

I mean really is it not interesting to think about? It has actually sparked the interest and desire in me to really take your advice, look more into the nature of how these things work. I am gaining the drive to get back into at least trying to allocate reasonable time into getting the popcorn and watching back to back Lewin lectures.

As I said before I agree everyone could technically just put the 0 resistance debacle aside and simply assume R=0 is similar to R=.00000000000001 is an empirical comparison only in the parameters of your test.. but I personally would find the ensuing debate much less interesting than what is currently being discussed because the point would simply be to do sort of a "haha see! you don't know nuffin about circuit theory!".  You don't think at least Brad would be offended by that? What would we really learn in comparison to if we were to practice your same exercise, in a different way, using the types of variables we are more likely to find on a work bench?

MileHigh

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Re: Joule Thief 101
« Reply #2402 on: May 11, 2016, 08:04:36 PM »
I am glad that you are getting the desire to look into things more and understand better.  However...

It's not a case of "Ha! Ha! See!"  I have already covered that so I am asking you to stop it.

One more time:

There was a scandal in Canada very similar to the Flint Michigan water crisis.  During the investigation they put people on the stand that were responsible for the water filtration and purification system.  It turned out those jackasses had no clue, they knew nothing about the system or water purification.  They were asked basic questions about water purification on the stand in front of a judge and the public and the press and they had no clue, they broke down and cried.  They had a fiduciary responsibility to provide clean drinking water to their town and they were lazy asses and failed miserably.  Would you like to be a resident of that city and having your children drink that water?  How about hiring a consultant to check out the house you want to buy for $400 and the guy has no clue?

EMJunke was running a thread for months pitching "partnered output coils" (he is still doing it) and I knew that he was bluffing and had no clue.  I asked him if he wanted to answer the simple question we are discussing now.  He agreed to answer the question and he failed miserably.  He was totally clueless.

Now do you get where I am coming from and why I asked EMJunkie?  If you get it then you must stop going back into defensive mode and giving me crap.

Brad wanted to discuss the same question of his own volition and that's why we are here now.

Now, all of the "gurus" are chiming in and Brad is clearly in the wrong.  The only issue is when is he going to move forward, as well as you and anybody else interested.  The goal is try to answer the simple question and get it right, and more importantly, demonstrate that you understand the issues and show competence in the subject matter.

Magneticitist

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Re: Joule Thief 101
« Reply #2403 on: May 11, 2016, 08:31:33 PM »
I am glad that you are getting the desire to look into things more and understand better.  However...

It's not a case of "Ha! Ha! See!"  I have already covered that so I am asking you to stop it.

One more time:

There was a scandal in Canada very similar to the Flint Michigan water crisis.  During the investigation they put people on the stand that were responsible for the water filtration and purification system.  It turned out those jackasses had no clue, they knew nothing about the system or water purification.  They were asked basic questions about water purification on the stand in front of a judge and the public and the press and they had no clue, they broke down and cried.  They had a fiduciary responsibility to provide clean drinking water to their town and they were lazy asses and failed miserably.  Would you like to be a resident of that city and having your children drink that water?  How about hiring a consultant to check out the house you want to buy for $400 and the guy has no clue?

EMJunke was running a thread for months pitching "partnered output coils" and I knew that he was bluffing and had no clue.  I asked him if he wanted to answer the simple question we are discussing now.  He agreed to answer the question and he failed miserably.  He was totally clueless.

Now do you get where I am coming from and why I asked EMJunkie?  If you get it then you must stop going back into defensive mode and giving me crap.

Brad wanted to discuss the same question of his own volition and that's why we are here now.

Now, all of the "gurus" are chiming in and Brad is clearly in the wrong.  The only issue is when is he going to move forward, as well as you and anybody else interested.  The goal is try to answer the simple question and get it right, and more importantly demonstrate that you understand the issues and show competence in the subject matter.


I can completely understand your analogy assuming the context of this site being a place to receive electronics tutoring courses. As ironic as that would be on 'overunity.com', I am not prepared to argue against the discussion of basic circuit analysis being an integral part of the entire electronics
field. I appreciate you are willing to help, because nowhere during the course of you earning your credentials were you told you would be absolutely required to tutor others. So having said that we know you are offering aid at your own accord and expense of time, but imo are complicating it without volition because your question takes ones focus from an actual bench experiment to one of imagination, and one that can hardly resemble anything most experimenters would have on the bench. I've said before if this lesson/test was portrayed in a manner that more closely followed the scientific method, which it currently cannot, I would be more glued to the screen than I am now and eagerly suck up the knowledge knowing how easily I would be able to see the real world results before my eyes.  I understand that you could be essentially attempting to 'set the stage' and prime someone like myself with the 'simple basics' before moving to a real circuit, but at this point we should be able to admit it has become more complicated than necessary.. If we are to forget the R=0 business and move on, continuing to analyze a circuit that does not closely parallel anything we have going on in the real world right now,  I personally have no desire to commit because it totally derails me from the information I came into the forum looking for.

MileHigh

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Re: Joule Thief 101
« Reply #2404 on: May 11, 2016, 08:32:32 PM »
Actually all the sims and the gurus have stated otherwise MH,, and that is ONLY because of the extraneous information you provided.

If you only stated that you have a perfect 5h inductor,,

As has been demonstrated, the sim chokes if zero resistance is used and that is for the very reasons I have already posted.

When you set di/dt the other information you posted should be ignored, that is what the gurus have done,, but to do that they have had to include a resistance,, that in and of itself should not a problem until you then require that they use all of the information provided,, then there is a problem.

Brad is simply taking the other information you provided and using that consideration,, 0 resistance and 0 capacitance => ideal coil => ideal inductor which =>? current at 4V?

Being the master that you are MH,, with an inductor with 0 resistance and 0 capacitance and 4V supplied by an ideal source with infinite current available,, what would the current be?

All I did there is remove the 5h value,,

You are lost Webby and an annoyance and I suppose this time you are trolling out of blind ignorance.  At this point your best action would be to be quiet, keep your hands in your pockets, and watch the blinking lights.

MileHigh

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Re: Joule Thief 101
« Reply #2405 on: May 11, 2016, 08:46:42 PM »
Not trolling and I am not ignorant. ( well maybe somewhat ignorant )

Your best action would be to state the obvious, your question was in error and as the question was stated described an impossible condition.

The question was not in error and it's just ignorance again.

MileHigh

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Re: Joule Thief 101
« Reply #2406 on: May 11, 2016, 08:49:07 PM »
I understand that you could be essentially attempting to 'set the stage' and prime someone like myself with the 'simple basics' before moving to a real circuit, but at this point we should be able to admit it has become more complicated than necessary.. If we are to forget the R=0 business and move on, continuing to analyze a circuit that does not closely parallel anything we have going on in the real world right now,  I personally have no desire to commit because it totally derails me from the information I came into the forum looking for.

Earlier on in this thread I clearly demonstrated to you that this can be replicated on the bench with 99.99% similarity to what is being discussed here.  All that you have to do is reduce the inductance, lower the voltages and shorten the timing.  That is the real world.

And I will tell you one more time, this directly applies to building pulse motors and Joule Thieves.  If you can't see that right now, it doesn't matter.  You would have to figure that out for yourself.  Knowledge builds upon knowledge.

Magneticitist

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Re: Joule Thief 101
« Reply #2407 on: May 11, 2016, 09:50:52 PM »
Earlier on in this thread I clearly demonstrated to you that this can be replicated on the bench with 99.99% similarity to what is being discussed here.  All that you have to do is reduce the inductance, lower the voltages and shorten the timing.  That is the real world.

And I will tell you one more time, this directly applies to building pulse motors and Joule Thieves.  If you can't see that right now, it doesn't matter.  You would have to figure that out for yourself.  Knowledge builds upon knowledge.


But you did not demonstrate that.. that is the problem! this is the entire debate.

following the scientific method you have constructed your hypothesis
that it will be 99% similar in theory as it would be in the real world.

Until you can obtain an impossible inductor that can be placed within a
circuit that has absolutely 0 resistance, you have yet to even test it in
an experiment. You may have tested a very low resistance coil, so you know,
you can establish that as more than hypothesis.

The 0 resistance circuit you cannot. It shall remain hypothesis until proven
otherwise. Were you to simply concede to that infallible logical conclusion,
some of us would probably provide a little more adherence to the remainder
of your intended lesson. The issue at hand most members (from what I can tell)
at this point have with the argument, is that you are unwilling to concede to
there being no possible way to gain absolute surety about any aspects
of a circuit analysis if we include a variable of 0 resistance, and leave the
rest of the many other possible variables as vague exclusions.

All of that could have easily be sidestepped were you to simply avoid real world
comparisons and state that your test parameters include physics where R=0
and R=.00000000001 yield no great distinction deserving concern.

partzman

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Re: Joule Thief 101
« Reply #2408 on: May 11, 2016, 10:12:31 PM »
Here is another sim which will be my last on this subject unless requested otherwise.

This shows the same 5 H inductor with a dcr = 1e-15 ohms plus stepped dcr's of .1, .5, and 1 ohm respectively.  The resulting current traces are marked on the plot and as can be seen, the current reaches a lower peak level with each increase in dcr. These values can be calculated by using the time constant formula, delta I = Vin/dcr(1-1/Eu^t/tau).

Eu is Euler's constant = 2.7182818 .

t = time Vin is applied in seconds .

tau = time constant = L/R

Solving for the .5 ohm step, we have 4/.5*(1-1/2.7182818^3/10) = 8*(1-1/2.7182818^.3) = 8*(1-1/1.3498588) = 8*.2591817 = 2.07345 amps which agrees with the sim.

The observation to be made here is that as the dcr decreases, the peak current reached in the inductor under the same given conditions increases but always starts at zero. IOW, the trend as we approach zero is that we see more of a pure inductance. 

My questions then is, at what point do we all of a sudden lose the property of inductance as we decrease the dcr and become either a short circuit or an infinite inductance?

I might add that with my current LtSpice parameter set, I can run this simulation successfully with a dcr = 1e-320 with the same results as dcr = 1e-15.  With a dcr = 1e-325 an error message states it can not properly solve the matrix needed to complete the simulation.

Just for comparison, the current super-conducting electromagnets used in MRI scanners have a typical dcr in the range of 1e-11 to 1e-12.

partzman

MileHigh

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Re: Joule Thief 101
« Reply #2409 on: May 11, 2016, 10:14:40 PM »
Magneticitist:

I am not going to argue this any more.  You are just going to have to accept or cope with the fact that people can discuss circuit behaviour using ideal components and then very easily apply that knowledge to the actual circuits that they are working with on the bench.  Your argument is invalid, and I have heard it countless times before from people in a similar position to you.

The question as posed without a single modification can be answered with 100% accuracy.  Then, a keener could get a big negative feedback operational amplifier, insert a resistor for current sensing just before the output of the amplifier and the voltage sense, and then make extremely accurate measurements of the ideal voltage and associated current being put into the device under test.  For example, the device under test could be a single low-resistance coil or some kind of filtering circuit.

If you don't accept this, then there is nothing that I can do about it.  It's not for me to convince you, it's for you to convince yourself and change your attitude and embrace knowledge and embrace stuff that will help you do better experiments.

MileHigh

MileHigh

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Re: Joule Thief 101
« Reply #2410 on: May 11, 2016, 10:24:17 PM »
Partzman:

That's awesome, thank you so much for running that sim!  I have to laugh about the dcr = 1e-320.  That means you can compute the solution with a time constant that's way way more than 10,000 trillion times the age of the Universe!   But if you set the dcr to 0 then we all die and we have a singularity and time folds in upon itself...

MileHigh

MileHigh

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Re: Joule Thief 101
« Reply #2411 on: May 11, 2016, 10:26:06 PM »
<<< My questions then is, at what point do we all of a sudden lose the property of inductance as we decrease the dcr and become either a short circuit or an infinite inductance?  >>>

Perhaps Brad can shed some light on that one...

Magneticitist

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Re: Joule Thief 101
« Reply #2412 on: May 11, 2016, 10:47:28 PM »
Magneticitist:

I am not going to argue this any more. You are just going to have to accept or cope with the fact that people can discuss circuit behaviour using ideal components and then very easily apply that knowledge to the actual circuits that they are working with on the bench.  Your argument is invalid, and I have heard it countless times before from people in a similar position to you.

The question as posed without a single modification can be answered with 100% accuracy.  Then, a keener could get a big negative feedback operational amplifier, insert a resistor for current sensing just before the output of the amplifier and the voltage sense, and then make extremely accurate measurements of the ideal voltage and associated current being put into the device under test.  For example, the device under test could be a single low-resistance coil or some kind of filtering circuit.

If you don't accept this, then there is nothing that I can do about it.  It's not for me to convince you, it's for you to convince yourself and change your attitude and embrace knowledge and embrace stuff that will help you do better experiments.

MileHigh


I really thought I was making it clear that I was in total agreement with you on that statement in bold. But in this situation the mixture of ideal source and ideal inductor made the real world comparison a mathematical impossibility, that is the problem. The question you posed could not,
cannot, and for all we know, will not be answered 100% 'perfectly'. Your modification of the question involving an R value could however as far as I can tell.

Magneticitist

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Re: Joule Thief 101
« Reply #2413 on: May 11, 2016, 11:14:34 PM »
does 'pure' inductance mean infinite inductance? which could possibly be construed as 0 inductance?

Magluvin

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Re: Joule Thief 101
« Reply #2414 on: May 11, 2016, 11:33:10 PM »
It is really not such a huge mental leap to imagine an inductor with zero resistance.  Can you imagine an inductor with 0.000001 ohms resistance?  Can you imagine an internal combustion engine where the main crankshaft bearings are replaced by "magic" bearings having no resistance?

I told Brad to go ahead and try to answer the question by adding a 0.000001 ohm resistor to the inductor to "fix the problem" and he passed on that.  So zero ohms or 0.000001 ohms, Brad was incapable of answering the question.  Progress is currently running at about one millimeter per day.

Anybody can open up a book or do some Googling.  Every single student that takes an electronics course ends up perfectly understanding ideal capacitors and ideal inductors. Think of the ICE as a very similar hypothetical example.

Sometimes things seem to be tough and you have to learn then.  That's all there is to it, you have to learn them and master them.  Repeatedly saying "the current goes to infinity because the resistance is zero" is ridiculous, you absolutely must learn what inductance is if you are going to progress and get more out of your experimenting.  If you truly knew what inductance really is, you would scoff at the notion that the current goes to infinity in an ideal inductor.

I dont see the problem with learning inductance while including resistance.  My build of Lasersabers motor has 24 coils in series. 3200 turns of 42awg each, 650ohm each coil. 15.6kohm all in series. each is 83mh for a total of near 2h. While running there isnt much if any curve of current rise. Looks fairly square pulses.  So on the far end of resistance where it is very high, the field tends to build very quickly with all that resistance (and inductance) because the current is more restricted from rising any further due to high voltage division across the board.

I just dont see that one would have to learn inductance through ideal circumstances. All one has to do is try say 3 different resistance levels, very low, medium and very high, with a known inductor and see the effects, and it would be real world effects that would be learned.

Mags
« Last Edit: May 12, 2016, 03:43:14 AM by Magluvin »