MH's ideal coil and voltage question

[tinman]

@MH

Let me just clarify this for the last time.

The question, in the way it is asked implies that with one application of an ideal voltage of 4V to an ideal inductor of 5H will produce in that one action the following effects in a continuous sequence. Consider the effect is a resulting single sine wave from that one first single action of applying that one instance of 4V for a duration of 14 seconds then to infinity.



All this happens with only that first application of 4V at t0 and from there with only that 4V applied to the inductor, the voltage measurements across the inductor would indicate those voltage values from 2 to 6 in those time intervals, but always with that first 4V applied to the inductor. No stopping, manually changing voltage levels. Those voltage levels shift down and up on their own because of the action of that first 4V introduced into that inductor.

That's how your question was asked. That's why I was against your question. But again this is your lack of precision, not mine. You should have seen that something was not understood by the way your question was asked. IT WAS YOUR QUESTION. You should have known that after 2-3 pages of heated rebuttal that you needed to ask us to first explain what the question means. PRECISELY. Instead you kept pushing this bad question and chastised us for what?

The question the way I understood it was impossible to answer or maybe you would like to take a crack at it as I have explained above. I even tried to make heads or tales of it working out a logic base. Now that I know these are 6 independent events of ideal voltages applied to a 5H inductor, this question just went from 1000% difficulty to 2% difficulty. I was actually impressed that your Method #1 could have been a real scenario and I just could not figure it out. But now I know it was a Method #2 question which is just more rudimentary EE. Basically a false flag event.

Actually I should be commended for trying to at least work some logic into Method #1. hahahahaha

So again, this does not show how a coil works. It only shows how a coil responds. There is nothing in EE that shows how a coil works. That falls into the realm of physics where my Spin Conveyance will shed the light. From there it will migrate to EE and other disciplines.

I have 35 years as a water treatment professional. I have worked with ions and ions don't lie. When you realize how your coil works you will have to start over with your EE. You will have to create new math, new formulas (hehehe), new models. Or, the present math will have new correlations to cause and effect. This is not a bad thing. It will open up a whole new Renaissance of knowledge that Faraday was to chickenshit to realize because his balls were tied tight with his bosses fields. So it was a good stoop.

So here is a question for you. Why does the current never rise above the applied voltage? Why does it always ride at a certain percentage below? Why have I been talking about Half Coil Syndrome?

Now if this has been closed maybe I can go back to the JT thread when I get back from work I can post some new effects patterns that none of you have ever seen before and we can really talk about how a coil responds (not works) instead of this water in a pipe business.

@tinman

OK, here is a close analogy to how a coil responds (not works) with water in a pipe under the DC model.

You have two pumps, one on each end of a length of pipe both pumping into the pipe. Each pump is first connected to a tee connection where the pump is one end, a valve that opens and closes on one end and the pipe length is on the third end. One pump is your positive connection, the other is your negative connection. As your coils are plugged usually one connection is always connected and the other is always pulsed. Each pump has a rheostat. The positive side pump it set at 60%, the negative side pump is set at 40% of available voltage. So if you are pulsing the negative side, only that side pump turns on and off while the other polarity pump is "always on". When the pulsed pump is on, the valve on that same side is closed. When that same pump turns off, the valve on that same side opens. The valve on the always pumping side is always closed. Both pumps draw from the same tank. Each side also has a higher cracking pressure check valve that returns to the tank plus those two valves also return to the tank. By this you will realize that pulsing a coil on the negative will always cost 60% for rebias for 40% change, while if you pulse the positive side of the coil it will cost 40% rebias for 60% change. This analogy is still wrong because we are using water that can only flow. This automatically is not the right way to see it. A close physical way would be if there was a way to introduce a colored die into the water at pulse on and then retract that die at pulse off. The water never really moves. Actually even the die analogy is not right because it is much simpler then that but for physical means they come close enough. Maybe 40% close. hahahahahaha

wattsup

Method #1

1) the sine wave starts at 4 volts for 3 seconds
2) the same sine wave then drops to 0 volts for 2 seconds
3) the same sine wave then drops to -3 volts for 2 seconds
4) the same sine wave then rises to 0.5 volts for 7 seconds
5) the same sine wave then drops to 0 seconds for infinity.

Wattsup.
I dont see any confusion with the way MH has stated the question.
There are no sine waves in the voltage pattern.
MHs question describes a square wave pattern for the voltages--no sine waves.

I have always pictured the voltage pattern as being exactly what Poynt posted some pages back--see below.

The ideal voltage source,and the ideal coil has never been an issue. The confusion between what myself and MH,was in the words MH chose. When he said the voltage varies in time,i took it as meaning like the current varies in time through the inductor---just MHs bad choice of words that can have many meanings. The correct meaning as far as the question is stated,and the fact that a fixed voltage value is selected for a period of time(dose not vary),would have been to say--where the voltage value can be changed by the user at any point in time,but where the voltage value is not changed by the load-being the inductor.

The only way the voltage can vary from the ideal source at one point in time,is if the user (or timing device) makes that variation. As you can also see,more confusion has been added by talk of ideal AC voltage sources--which is not applicable to the question.


Brad

[poynt99]

It helped Wattsup to notice that he needs to be more careful with his words.
These are technical posts and every word matters. Making mental shortcuts is sometimes funny but most often it requires "secret decoder rings" from the reader.  Those are not good habits for technical communication.

So now we have established that an ideal voltage source merely needs to have:
- zero internal resistance
- zero internal reactance
- an output voltage that is not affected by the load

...but it does not need to output a constant output voltage all the time, and it can be even an ideal alternating voltage source.

We can consider the direction of the current flowing through this ideal voltage source.

Brad will like this:
The current can flow in two directions through the voltage source and the voltage presented by this voltage source can have two polarities, too.  So we have 2 variables and each one can have 2 states.  This gives us 4 combinations.

Of course this is again the 4-quadrant operation, where:
- 2 combinations result in energy flowing from the voltage source to the load
- 2 other combinations result in energy flowing from the load to the voltage source

Can you enumerate which ones?

Good post verpies.

[poynt99]

@ Poynt

The best i can do as far as an inductor i have in the work shop,is a 1 Henry coil with 1.6 ohms of resistance.
This is a very large inductor out of a 300 amp HF mig welder.
Nothing else comes even close to the 5 Henry coil needed,with a low resistance value.
I do have a large MOT,and that is .71 Henry,and a resistance of 1.2 ohms.

I still think we could see the desired effect i am talking about with one of these inductors.

The welder coil has the better L/R ratio of the two (0.625), but it is a far cry from 50, which is what we need to be close to ideal.

From the first plot below (red trace is MH's, violet trace Brad's coil), you can see that the lower value inductance and significantly higher series resistance (dissipating the inductor's energy) produces a result that is far from the ideal. So it seems this scheme as it stands won't work.

However, there is some hope. We can sort of "translate" our L/R ratio of 0.625 to 50 by significantly shortening the timing on the input source. We have little control over the real world L/R ratio, but we do have control over the input timing, which we can manipulate to utilize the "linear" portions of the circuit rise/fall transitions. We will shorten it by a factor of 1.6 x 50 = 80. So now our wave form timing becomes the following:

t0=0s
t1=37.5ms (was 3s)
t2=62.5ms (was 5s)
t3=87.5ms (was 7s)
t4=162.5ms (was 13s)
t5=250ms (was 20s)

From the second plot below you can see we've made a significant improvement in the "idealness" of our experiment, and will produce results good enough to compare to MH's original specs.

So the remaining challenge will be to design a source that can output this wave form.

[poynt99]

For comparison sake to see how far off we are from "ideal" using our shortened wave form timing and non-ideal inductor, see below for Brad's coil with an R=1m Ohm (close enough for ideal), the same as used for MH's inductor. The wave form timing is still the shortened version.

[MileHigh]

@MH

Let me just clarify this for the last time.

The question, in the way it is asked implies that with one application of an ideal voltage of 4V to an ideal inductor of 5H will produce in that one action the following effects in a continuous sequence. Consider the effect is a resulting single sine wave from that one first single action of applying that one instance of 4V for a duration of 14 seconds then to infinity.

Method #1
1) the sine wave starts at 4 volts for 3 seconds
2) the same sine wave then drops to 0 volts for 2 seconds
3) the same sine wave then drops to -3 volts for 2 seconds
4) the same sine wave then rises to 0.5 volts for 7 seconds
5) the same sine wave then drops to 0 seconds for infinity.

All this happens with only that first application of 4V at t0 and from there with only that 4V applied to the inductor, the voltage measurements across the inductor would indicate those voltage values from 2 to 6 in those time intervals, but always with that first 4V applied to the inductor. No stopping, manually changing voltage levels. Those voltage levels shift down and up on their own because of the action of that first 4V introduced into that inductor.

That's how your question was asked. That's why I was against your question. But again this is your lack of precision, not mine. You should have seen that something was not understood by the way your question was asked. IT WAS YOUR QUESTION. You should have known that after 2-3 pages of heated rebuttal that you needed to ask us to first explain what the question means. PRECISELY. Instead you kept pushing this bad question and chastised us for what?

The question the way I understood it was impossible to answer or maybe you would like to take a crack at it as I have explained above. I even tried to make heads or tales of it working out a logic base. Now that I know these are 6 independent events of ideal voltages applied to a 5H inductor, this question just went from 1000% difficulty to 2% difficulty. I was actually impressed that your Method #1 could have been a real scenario and I just could not figure it out. But now I know it was a Method #2 question which is just more rudimentary EE. Basically a false flag event.

I think the question is clear enough.  A voltage source is connected across an inductor.  The voltage is a step waveform with various voltage levels, what happens?

Some people didn't even know where to begin.  That is very telling.  What happens?  The only unknown is the current, solve for the current.

Honestly, all these words that you are throwing at my question itself are too much.  The question is what it is.

MileHigh