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Author Topic: Switched capacitor motor  (Read 29515 times)
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I am saying that if there is no energy gain in the 1st cycle then there will be no gain in subsequent cycles.

But I think you will agree that a PM rotating relative to some permeable material will create mechanical energy gain (during the attractive approach) only for that energy to be lost (during the attractive recede).  I am trying to break that reciprocity by creating the effect of the permeable material being present by supplying current to a coil in a manner that exactly simulates that effect for the gain phase, then removing it for that energy claw back phase.

Quote
The 1st cycle can be made equivalent to subsequent cycles when its initial conditions are the same for the same rotor position.

For example:
1) the rotor at 90º.
2) capacitor charged to some voltage V
3) no current flowing through the winding L

Agreed

Quote
Analysis:
As capacitor is discharged into the winding, electric current flows through the winding and generates magnetic flux.  If the PM rotor were immobilized then this current would vary sinusoidally in time due to the self-inducance of the winding and the LC relationship with the capacitor, but since the rotor can move, the magnetic gradient attracts it and it moves/rotates.
The approach of the magnet induces current in the winding that is in opposite direction to the current discharging from the capacitor.  These two currents oppose and fight each other thus the current flowing through the winding is not sinusoidal, anymore.

I disagree.  First any two currents that are "fighting" each other and are both sinusoidal, the resulting current as also sinusoidal.  Second the moving magnet does not induce current, it induces voltage.  (The way Lenz's Law is expressed leads to wrong statements like your "induces current in the winding that is in opposite direction to the current discharging from the capacitor".)  To establish the direction of current you have to look at the effect that the induced voltage has on the circuit, and the effect of that induced voltage is not as you state.  You do not have two currents fighting each other.  You have a capacitor discharging current into an impedance where the voltage is changing sinusoidally, and that leads to that current also being sinusoidal.  It is exactly like the capacitor being discharged into an inductor.

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If the winding were unpowered by the capacitor yet shorted, then the approach of the rotor would still induce the same current in this winding and in the same direction as with the powered winding.

Totally disagree.  Again you are fixated on induced current whereas changing flux induces voltage.  Any current that flows as a result of that voltage has to take account of the load into which that current flows.  A short across the coil cannot possibly be considered the same as a pre-charged capacitor.  The current cannot possibly be the same for those two cases.

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Also, an unpowered shorted winding repels the rotor while a powered winding attracts the rotor (if the powering current is greater than the induced current).

That should really be stated as "a powered winding attracts the rotor (if the powering voltage is greater than the induced voltage so as to drive current of the correct polarity).  If the powering voltage is smaller than the induced voltage the current flows in a direction to create repulsion, of which the shorted coil is the limiting case of zero applied voltage.

Quote
Some people prefer to call it CEMF.
Consequently, the ½Li2 energy stored in the powered winding/coil at TDC (0º) is smaller when the rotor is allowed to approach to it vs. when it is not allowed to approach.

Well my analysis does not show that, but of course my analysis could be wrong.

To add further to this debate consider this.  A magnet without a keeper has energy stored in the external and internal magnetic fields.  The external field is in air while the internal field is within the inter atomic space, so also stored in "air".  When a keeper is in place the external energy has disappeared.  It can be shown that during approach of the keeper there is a flow of magnetic energy from the external air into the internal "air".  There is also another flow of energy from the electron dipoles into the internal "air".  Those two flows of energy account for the final energy stored internally where the magnet's load line has moved and the B within the magnet has increased.  All these flows of energy can be calculated, but they never feature in any analysis of magnetic motors because they do not normally feature in overall power output.  But they do feature in that cyclic energy-gain energy-loss situation associated with cogging torques.  If you analyse a PM motor that has permeable material in its construction, looking at electrical energy input v. mechanical energy output over small time or angle increments, you will find areas of overunity and underunity.  These cancel out over full cycles.  The OU areas occur when energy is being extracted form the electron dipoles, the UU areas when it is being clawed back.  If we can break that reciprocity we can obtain overall OU.

Smudge
« Last Edit: 2015-08-26, 10:17:02 by Smudge »
   
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ION,

Try this one.

Smudge

In diagram where capacitor is being charged - what force is going to be used for charging? As soon as you close circuit the Lenz force will be there against magnet unless you have clever way to redirect it for doing useful work.
   
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In diagram where capacitor is being charged - what force is going to be used for charging?

The capacitor is being charged while it is disconnected from the coil, so there is no Lenz effect on the charging process.  Ideally we want the capacitor to obtain its energy from the bemf spike when the switch is opened so that the ½Li2 energy stored in the coil gets transferred into the capacitor ready for the next switch closure.  But it has to get there in the correct polarity, so it requires some clever circuitry to do that.

Quote
As soon as you close circuit the Lenz force will be there against magnet unless you have clever way to redirect it for doing useful work.

Not sure what you mean by Lenz force.  The capacitor discharging into the coil sends current so that the magnet creates positive torque thus doing useful work.

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But I think you will agree that a PM rotating relative to some permeable material will create mechanical energy gain (during the attractive approach) only for that energy to be lost (during the attractive recede).
Yes

I disagree.  First any two currents that are "fighting" each other and are both sinusoidal, the resulting current as also sinusoidal.  
While you are correct that a sum (or difference) of two sinusoids yields a sinusoid (or zero) regardless of their phase, the induced current is not sinusoidal because the magnetic flux cutting the crossection of the winding does not change sinusoidally in the rotor/pole geometry that you have drawn.  So sinusoidal LC current + non-sinusoidal induced current = non-sinusoidal total current.
This is a minor point in our discussion that has no bearing on your operating principle.

Second the moving magnet does not induce current, it induces voltage.  
Voltage is just a potential, in other words "what might be".  An inductor is a current device and a real event in it is the current flow.  An inductor with voltage across it but without current flowing through it (e.g. an open inductor) is equivalent to nothing.  It does nothing, it might as well not be there at all.  
So forgive me if I analyze inductors in terms of currents and capacitors in terms of voltages.

(The way Lenz's Law is expressed leads to wrong statements like your "induces current in the winding that is in opposite direction to the current discharging from the capacitor".)  
I also have a problem with the Lenz law, however it is not about the precedence of voltage over current but my objection is that it is a qualitative law and not a quantitative law.  
I'd like to have a quantitative Lenz law stating, that the current induced in an ideal shorted inductor generates its own magnetic flux that acts to maintain the total flux penetrating the inductor, at a constant level.  Any imperfections of the inductor, such as resistance and self-capacitance are a different story.

To establish the direction of current you have to look at the effect that the induced voltage has on the circuit, and the effect of that induced voltage is not as you state.  
Both the direction and magnitude of the induced current are as I state.  This can be seen merely with a CSR and an oscilloscope.
An inductor is a current device and it is the current that generates magnetic flux in it - not voltage.

You do not have two currents fighting each other.
You do have fighting currents in your device, because the induced current is subtracted from the current delivered by the capacitor.

You have a capacitor discharging current into an impedance where the voltage is changing sinusoidally, and that leads to that current also being sinusoidal.  It is exactly like the capacitor being discharged into an inductor.
Yes, that is the shape of the current flowing in the inductor when it is supplied by voltage from a capacitor. A classic LC behavior.  But the induced current is a different story - it is neither sinusoidal (because the flux is not) nor in the same direction as the current delivered from the capacitor.

Totally disagree.  Again you are fixated on induced current whereas changing flux induces voltage.
It is not an accident nor fixation.  The cherished concept of induced voltage (Faraday's law) is useless when analyzing the response of an ideal shorted inductor to a changing external flux.

And the proper approach to analysis is to start with ideal components first and add the imperfections later.

Any current that flows as a result of that voltage has to take account of the load into which that current flows.  
Yes, but the concept of current caused by voltage (Ohm's law i=V/R) is not always useful and blindly following it can lead you down the garden path.  Analysis of currents induced in inductors, subjected to changing external flux, is a perfect example of this.

Just consider whether the calculation of induced voltage in an ideal shorted inductor, subjected to a changing external flux, leads to any good answers ...if you try, you get i=V/0 from the Ohm's law and no clue to what the induced current in that inductor really is.  (...and it is neither infinite nor zero).

I remind you, that only current flowing in the inductor represents the energy stored in the inductor at that moment and only the current produces any measurable effects.

A short across the coil cannot possibly be considered the same as a pre-charged capacitor.  The current cannot possibly be the same for those two cases.
Of course it is not, because capacitor is a voltage device and a coil is a current device.  A shorted coil stores energy in the form of current and an open capacitor stores energy in the form of voltage....or internally as magnetic field and electric field, respectively.  The behavior of the LC circuit stems from sloshing of the energy between these two forms.

That should really be stated as "a powered winding attracts the rotor (if the powering voltage is greater than the induced voltage so as to drive current of the correct polarity).  
Involving voltage in inductor analysis is unnecessary and leads down a garden path.
I would make the same objection if you were fixated on current in capacitors.

Now I have to write that you are "fixated" on voltage instead what really matters in an inductor - current.  Voltage across an ideal shorted inductor cannot even be measured and a shorted inductor is the active inductor.  

An open inductor is inactive and it neither stores energy nor builds the magnetic flux, while a shorted inductor - does.
Conversely, a shorted capacitor is inactive and neither stores energy nor builds the electric field, while an open capacitor - does.


If the powering voltage is smaller than the induced voltage the current flows in a direction to create repulsion, of which the shorted coil is the limiting case of zero applied voltage.
I agree but the same conclusion can be reached just analyzing currents in the inductors.
The capacitor powering an inductor is a variable voltage source and as you probably know, the internal impedance of an ideal voltage source is zero, so the inductor is effectively shorted by zero impedance and and its response to an external changing flux is the same as that of a shorted inductor.
   

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To add further to this debate consider this.  A magnet without a keeper has energy stored in the external and internal magnetic fields.  The external field is in air while the internal field is within the inter atomic space, so also stored in "air".  When a keeper is in place the external energy has disappeared.  It can be shown that during approach of the keeper there is a flow of magnetic energy from the external air into the internal "air".  There is also another flow of energy from the electron dipoles into the internal "air".  Those two flows of energy account for the final energy stored internally where the magnet's load line has moved and the B within the magnet has increased.  All these flows of energy can be calculated, but they never feature in any analysis of magnetic motors because they do not normally feature in overall power output.  But they do feature in that cyclic energy-gain energy-loss situation associated with cogging torques.  If you analyze a PM motor that has permeable material in its construction, looking at electrical energy input v. mechanical energy output over small time or angle increments, you will find areas of overunity and underunity.  These cancel out over full cycles.  The OU areas occur when energy is being extracted form the electron dipoles, the UU areas when it is being clawed back.  If we can break that reciprocity we can obtain overall OU.
I understand.  I also think that there is energy to be had from there.
I just tend to lean towards soft ferromagnetic movers than the hard ones (magnets).

When a soft keeper/rotor is attracted by an active coil, the current circulating in the coil decreases as the ½Li2 energy stored in that coil is transferred to the keeper/rotor in order to grow and align its ferromagnetic domains.  That "domain alignment energy" can be later transferred back into the coil (and then into a capacitor) after the rotor passes TDC (90º in your drawing) in order to prevent back-attraction like in your scheme with the PM.  
During the latter transfer, the inductance of the coil with the keeper/rotor in its proximity is much higher compared to when the keeper/rotor was away, however the inductor current is lower.  

The circuit to do this recovery is related to the inverting buck-boost converter and is applicable to your design, too.  A synchronous rectification is highly recommended because diode voltage drops VF eat up the stored energy fast.
« Last Edit: 2015-08-26, 13:25:26 by verpies »
   

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Ideally we want the capacitor to obtain its energy from the bemf spike when the switch is opened so that the ½Li2 energy stored in the coil gets transferred into the capacitor ready for the next switch closure.  But it has to get there in the correct polarity, so it requires some clever circuitry to do that.
The circuit to do that connects an empty capacitor to a full coil and allows for ¼ of the natural LC oscillation cycle in order to transfer the ½Li2 energy stored in this coil (as current) to the capacitor (as voltage).  The circuit to do that is related to the inverting buck-boost converter.

Not sure what you mean by Lenz force.  The capacitor discharging into the coil sends current so that the magnet creates positive torque thus doing useful work.
I think he means that the capacitor represents a short to the coil as a voltage source so when the external flux changes the induced current will have a closed path and will occur in the direction dictated by the Lenz's law.  That current will create its own own magnetic flux that will generate an opposing force on the approaching rotor.
   
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Of course it is not, because capacitor is a voltage device and a coil is a current device.  A shorted coil stores energy in the form of current and an open capacitor stores energy in the form of voltage....or internally as magnetic field and electric field, respectively.  The behavior of the LC circuit stems from sloshing of the energy between these two forms.

Everyone is making some very good points. I have moved away from the common analogies concerning inductor currents and capacitor voltages. For instance a capacitor cannot "charge" unless a current of free electrons is flowing into (-) and out of (+) the capacitor. Thus in order to charge a capacitor a voltage (electrical pressure) is required to force a current (movement of charges)... it always takes two to tango.

As well in an inductor there must always be voltage to force a current. In a closed one turn loop we may presume there is no voltage however we know it must be present. The issue is easy to understand if infinite element analysis is used which is all I use. Consider a battery or charged capacitor connected to a coil, we can see the source as a separation of charges and in the coil we see these charges coming together and neutralizing themselves. However in a one turn loop our perceptions confuse the issue because we cannot see a singular source like a battery. In effect an induced one turn loop must produce a charge separation (voltage) in every section of the wire simultaneously and whenever the charges move as a current they must come together and neutralize their separation. To make a meaningful analogy we could say our one turn coil acts like a million small batteries connected in series forming a loop. We cannot measure the voltage because the potential difference causing motion or current is between the free electrons and protons at the atomic scale.

The induced one turn loop is where lumped sum analysis fails miserably because there is no "lump" to sum and the induction process occurs through a near infinite number of elements simultaneously. I understand we lump things together so doing calculations is easier however nature does not do calculations nor does it lump things together and call them something else. All this is very easy to understand however we have to see it for what it is, all matter is an aggregate of billions of smaller parts undergoing forces and moving about. What we call voltage or current is like herding cats and most of the simple equations we use seems quite absurd relative to what is actually happening to these billions of parts.


AC




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I have no problem with shorted loops because I can do dynamic analysis in the magnetic domain, something that is sadly lacking in our teachings.  You can easily verify that a coil connected to a load resistor appears in the magnetic circuit (where flux is "magnetic current") as a "magnetic inductor" whose value is N2/R.  For zero R the "magnetic inducance" goes to infinity hence the flux cannot change value, it remains at the value there when the coil is shorted.

I do have problems with regarding Lenz as always creating current that is of opposite polarity to that applied external flux.  A capacitor acting as a short will certainly get induced current opposing the changing flux if there is no previous charge on the capacitor, but it doesn't necessarily do that if there is already voltage on the capacitor at the time of connection.  If the capacitor is already charged to the open circuit voltage of the coil then at the point of connection there can be no current flow, so at that instant it is not a short.  What now follows depends on whether that open circuit voltage remains constant or not.  If the voltage is falling (because the flux rate is reducing) then the capacitor can discharge into the coil.  If the voltage is increasing then the opposite is the case, the current is charging the capacitor more.  So you can get either polarity of current.  Verpies doesn't agree with me on this point.

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I have no problem with shorted loops because I can do dynamic analysis in the magnetic domain, something that is sadly lacking in our teachings.  You can easily verify that a coil connected to a load resistor appears in the magnetic circuit (where flux is "magnetic current") as a "magnetic inductor" whose value is N2/R.  For zero R the "magnetic inducance" goes to infinity hence the flux cannot change value, it remains at the value there when the coil is shorted.

I do have problems with regarding Lenz as always creating current that is of opposite polarity to that applied external flux.  A capacitor acting as a short will certainly get induced current opposing the changing flux if there is no previous charge on the capacitor, but it doesn't necessarily do that if there is already voltage on the capacitor at the time of connection.  If the capacitor is already charged to the open circuit voltage of the coil then at the point of connection there can be no current flow, so at that instant it is not a short.  What now follows depends on whether that open circuit voltage remains constant or not.  If the voltage is falling (because the flux rate is reducing) then the capacitor can discharge into the coil.  If the voltage is increasing then the opposite is the case, the current is charging the capacitor more.  So you can get either polarity of current.  Verpies doesn't agree with me on this point.

Smudge

I think you have clearly explained it in the quote above and I agree.

Please check the optical disk drawing for agreement with your sequencer diagram.

Whether the  segments around the disk are cut out or not will depend on how the switching drive is hooked up and if there are inversions.

For a simple drive to a mechanical relay, an open slot equals light passing through equals relay activated, now it is matter of using the normally open or normally close contacts on the relay.

Nice thing about using a small relay would be bidirectional drive and low switch loss, disadvantage would be turn on / turn off delay at higher RPM's (could be offset with timing wheel angle adjustment relative to magnet position) and possible loss of energy in arcing contacts.

A simple low loss FET circuit can also work when made bi directional.

Also a simple bow tie pattern can be cut for an interrupter


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It's simpler than you imagined, the relay contacts have to be open or closed over 90 degrees of travel, hence the optical disc shown here.

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Just to add one more thing to the Lenz debate.  With a capacitive load the induced current is related to the rate-of-change of rate-of-change of flux.  In other words it involves a second differential.  Hence for AC flux the omega squared term in the value of negative reluctance created by the capacitor.  The second differential of a sine wave is a negative sine wave, hence the negative reluctance.  Lenz's law as written doesn't cover second differential, it only accounts for first differential.  I stand by the pictures I put in post #31.

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If the voltage is falling (because the flux rate is reducing) then the capacitor can discharge into the coil.  If the voltage is increasing then the opposite is the case, the current is charging the capacitor more.  So you can get either polarity of current.  Verpies doesn't agree with me on this point.

Ah now I see where your going.
I would have to agree on this point because this exactly how an induction motor/generator works. Higher than grid induced voltage = generator action and lower than grid induced voltage = motor action. I did many experiments in that strange region where induced voltage is equal to grid or line voltage where the motor/generator is neither a motor or a generator. It is very hard for many people not familiar with these concepts to wrap their mind around it.

As well the concept of energy is foreign to many, the fact that the energy in a conductor travels on the surface as a travelling magnetic field moving near the speed of light while the free electrons in the conductor move at a snails pace.  It is simply induction, one electron moves which creates a magnetic field which causes other electrons to move and reinforce the field which continues on down the line. This is why inducing one part of a coil induces the whole coil because it is still a piece of wire, it is simply wrapped in circles.

Another aspect is the mysterious disappearing voltage experiment I invented. We produce a separation of charges in a battery by adding electrons to the (-) terminal and taking them away from the (+) terminal. Simple enough, then we attach a resistor to the circuit and the electrons from the negative side of the circuit are resisted just as the positive side is also resisted. If the current is resisted from both the (+) and (-) legs of the circuit then somewhere near the middle of the resistance the charges should meet and become a neutral condition neither negative or positive. So I used a 2 foot length of nichrome wire as my resistance and a 12v battery as a source then measured the charged state at many points along the wire with an electrometer. From the negative side of the nichrome wire termination inward the charged state reduced to zero at the center of the wire just as the positive charged state reduced to zero at the center of the wire from the positive terminal. Thus we must conclude in every resistance the two charged states of (-) and (+) reduce through a gradient to zero at the center of the resistance due to the resistance.

You know I have never heard of anyone ever doing my simple experiment however I proved it through experiment to prove a very simple point. When charges are separated this represents an accumulation of energy. When separated charges are allowed to come together in a circuit element and neutralizing each others condition then this represents the dissipation of energy. Now you know how a resistor works fundamentally, why energy dissipates in it and why there is a voltage drop across it... because the voltage has ceased to exist.

This is why philosophy it is so important, we must first imagine what might be going on in a rational coherent way and then devise a way to prove it. Equations will not give anyone the answers they seek we must find our own answers. Now I must ask did anyone here understand the fundamental mechanism of how and why a simple resistor dissipates energy before I told you?, and if not then why did you not question it?.
Rule #1... question everything.



AC
« Last Edit: 2015-08-26, 23:32:49 by Allcanadian »


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Regarding the optical shutter, a slot can be cut at the edge of the disk, or just remove material at the edge of the disk. This is easily done with a small router bit and a pivot guide. Not necessary to hollow out the entire disk as this would probably create too much turbulence. I tend to prefer slots as they are less dangerous than sharp edges, except at high speeds.
if the material is thin enough, you can use scissors or tin snips.


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Ah now I see where your going.

AC
Your previous unedited post was pretty good, your finishing sentence something along the lines of "What I don't understand is where is the energy gain coming from" was quite to the point.

From my point of view harnessing an energy gain from a fundamental force model relies on manipulating the secondary scalar field, which is replenished instantly by the primary vector field being the energy source which energises it. I am also manipulating mass and density within my system to create a potential difference in the scalar field, and thus an imbalance.


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Your previous unedited post was pretty good, your finishing sentence something along the lines of "What I don't understand is where is the energy gain coming from" was quite to the point.

I can't seem to leave well enough alone and spam edit, lol. I agree and at some point there must a clear explanation of how the mechanism for gain works to produce a gain.


Quote
From my point of view harnessing an energy gain from a fundamental force model relies on manipulating the secondary scalar field, which is replenished instantly by the primary vector field being the energy source which energises it. I am also manipulating mass and density within my system to create a potential difference in the scalar field, and thus an imbalance.

I would agree and there must be a trick involved which I think may rely on a contradiction between laws or phenomena. For instance if one law states X must happen and another law states Y must then if we force both X and Y to happen in the same instance and they contradict one another then it's just a big old quagmire of contradiction and all bets are off. I think your on the right track and the key word here is "manipulation" in which we force a change in something which may not want to change. At which point our imagination and creativity comes into play to devise a way to bend the rules which may not want to bend. Essentially it comes down to our determination to change ourselves and our way of thinking which translates into our perception of reality. We may have been created equal however from that moment on what we do determines our fate.

Well I better get back to work, 34 C here, no wind and I figured I better let the tractor and myself cool off for a bit... were both getting a little old, lol.


AC



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HOLD THE FRONT PAGE, some unwelcome breaking news coming.

While disagreeing with Verpies on the direction of current flowing in this motor, I have just completed a FEMM simulation that reveals all.  First off I had to model a spherical magnet (actually a cylinder in the 2D FEMM) in order to get sinusoidal flux.  That produced flux so close to sinusoidal that you can't see the difference on the chart of simulated result and calculated result.  That's good, it means that I can use the step by step FEMM results and extrapolate them to continuous without introducing error.  And the quarter sine-wave rising current from the discharging capacitor creates flux that directly adds to the quarter sine-wave rising flux from the rotating magnet.  Of course my FEMM simulation did that because I applied that quarter sine-wave current in synch with the quarter rotation.  But I can calculate the value of capacitance for the real situation, and I can also obtain the voltage from the rising flux and that tells me the energy stored in the capacitor at the start.  So far so good.

Now the bad bit.  The interesting effect is that the rising current from the capacitor which is adding flux in-phase with the rising flux from the magnet (and that is not the two fluxes fighting each other, they really do add in-phase) means that the capacitor thinks it is connected to an inductor of different value to the actual coil inductance, it is greater.  In my sim the coil inductance is 1.27uH but the capacitor thinks it is connected to 14.1uH.  Of course this effective inductance is linked to the rotation speed, I used 1000rpm.  So for the capacitor to discharge all its energy in that quarter cycle movement it has to resonate with that 14.1uH.  That turned out to be a huge capacitor as expected, but the voltage needed was quite small because the frequency is so low.  Next I discover that the mechanical energy gained from the torque is slightly less that the energy originally stored in the charged capacitor (and eventually lost because the capacitor gets fully discharged over that quarter cycle).  But there is still energy stored in the inductance that is to be recovered.  If the inductance to be discharged were that higher value things would be good, but it isn't.  The inductor can only dicharge its self flux down to the level from the PM that exists at that point, the inductance value for that quick discharge is the basic coil self-inductance value.  And the small energy regained exactly made up for the difference between capacitor energy lost and mechanical energy gained.  The system is not OU, without any losses it has a COP of unity.

Verpies was almost right when he said "Consequently, the ½Li2 energy stored in the powered winding/coil at TDC (90º) is smaller when the rotor is allowed to approach to it vs. when it is not allowed to approach."  If he had said "Consequently, the ½Li2 energy stored in the powered winding/coil at TDC (90º) is smaller than the ½CV2 energy stored in the capacitor at 0º" he would have been spot on.  That is where I made my original mistake.

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Dear Smudge

You are a true scientist willing to double check your own hypothesis and report the negative finding when that occurs. This is very rare in the OU community so hats off to you Sir!  O0

All is not lost, your skill at working the FEMM analysis will be very helpful with some other projects here, I'm hoping you can join in.

Meanwhile, it would not hurt to build your device or some variation, as there may be some work around that is possible, that has not yet occurred to anyone.

Keep up the good fight, and keep it coming.

Kindest regards,
ION


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The inductor can only dicharge its self flux down to the level from the PM that exists at that point,
However, the inductor can discharge the total flux penetrating it, almost down to zero, when a soft ferromagnetic is used instead of the PM....because the soft ferromagnetic's flux joins with the inductor's flux and becomes accessible to it.

the inductance value for that quick discharge is the basic coil self-inductance value.  
..and with a soft ferromagnetic keeper/rotor, the self-inductance at TDC (90º) is much higher.
   
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@Smudge
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The inductor can only dicharge its self flux down to the level from the PM that exists at that point, the inductance value for that quick discharge is the basic coil self-inductance value.

I think you explained everything about as well as it can be explained in my opinion. The PM field saturates the inductor to a certain value proportional to the PM position which translates directly to the work it can perform. Also, the inductor can never fully discharge because the PM field is still present thus the work component is always proportional to the difference between the inductor field and the PM field.

At this point we must be very specific... where exactly did the input energy go?. We produced an inductor field of X acting on the PM field of Y and we are left with X minus Y. I think you will find in attraction or repulsion mode the field change which performs work always translates back to the coil as an increase in field density which saturates the inductor causing it to dissipate energy as heat. This is the fundamental reason why the input is proportional to the output in most machines. Now that we know the nature of the problem all we have to do is find a way to change this relationship to ensure it doesn't happen.


AC



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@AC

I don't like your use of the the word "saturate" since that implies we have material that can saturate in the usual sense of the word.  There is no such material there.  As regards where did the input energy go, it appeared as torque doing work and therefore created output energy.  Most of it that is.  The remainder was left behind as inductive energy that could be recovered.  The overall COP was unity.  I did not model losses so there was no energy dissipation via that route.

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However, the inductor can discharge the total flux penetrating it, almost down to zero, when a soft ferromagnetic is used instead of the PM....because the soft ferromagnetic's flux joins with the inductor's flux and becomes accessible to it.
..and with a soft ferromagnetic keeper/rotor, the self-inductance at TDC (90º) is much higher.

Good points, I'll do an FEMM simulation using an electromagnet in place of the PM, then at 90 degrees discharge both the drive coil and the magnet coil and see how the energies pan out.

For anyone interested in the FEMM simulation already done here are some details.  (Note this was not meant to be a practical motor, it was just something to explore the workings of the device)  Image of the magnet, coil and flux pattern shown below, the magnet at 0 degrees.  The thin rectangles either side of the magnet are the coil.  Magnet diameter 20mm and the FEMM depth was 25mm.  Coil was 10 turns and I used 100 amps as the final current so used a sine wave rising from 0 degrees to reach 100 amps at 90 degrees.  Then at any point the ratio of flux to current was the apparent inductance (all linear here so no need to use incremental values).

Other data:
Apparent inductance 14.12uH
Rotation rate 1000rpm,  frequency = 16.67 Hz, omega = 104.72 rad/S
Capacitor 6.459 F
Capacitor charged to 0.1479 V
Capacitor energy 0.0706 J
Energy delivered to shaft 0.0638 J
Flux at 90 degrees with 100 A current -0.001412
Flux at 90 degrees with no current -0.001285
Inductance of coil  1.27uH
Energy recovered from coil 0.00637 J
COP = 0.9935

Waveforms below for the flux, the torque and the power flows

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@evolvingape
I can't seem to leave well enough alone and spam edit, lol. I agree and at some point there must a clear explanation of how the mechanism for gain works to produce a gain.


I would agree and there must be a trick involved which I think may rely on a contradiction between laws or phenomena. For instance if one law states X must happen and another law states Y must then if we force both X and Y to happen in the same instance and they contradict one another then it's just a big old quagmire of contradiction and all bets are off. I think your on the right track and the key word here is "manipulation" in which we force a change in something which may not want to change. At which point our imagination and creativity comes into play to devise a way to bend the rules which may not want to bend. Essentially it comes down to our determination to change ourselves and our way of thinking which translates into our perception of reality. We may have been created equal however from that moment on what we do determines our fate.

Well I better get back to work, 34 C here, no wind and I figured I better let the tractor and myself cool off for a bit... were both getting a little old, lol.


AC

No trick, just correct integration of existing laws to produce a potential imbalance within multiple frames of reference.

Gravity has an axial vector straight down relative to us. The density of the fluid layers determines it's specific gravity and therefore order within the axial system.

Within the liquid layer there is a quantifiable hydrostatic pressure differential relationship within the scalar vertical axis.

Put that liquid in a bucket (encase it in a solid) and it has a weight vector and a scalar pressure differential.

Put one of those buckets on top of another of those buckets, and seal.. you have a weight vector active, a hydrostatic pressure differential inactive.. along for the ride down.

When the vector force has done work through equalisation, it has reached bottom of system travel. The scalar hydrostatic pressure field (the specific gravity field) potential is available and can be pressurised (compressed) by a vector force (hydraulic ram principle). If your weight ram is a liquid utilising the weight force vector only hydrostatic pressure equalisation_must_not_be_allowed_to_occur.. or you lose your significant compression differential.

The outcome of all this is that you can move liquid through a vertical height incurring losses, but reducing power rate over a period of time and restore your gravitational potential of the pumped liquid back into the reservoir. The liquid pumped through a water wheel and alternator can produce electricity.

The losses for water wheel and alternator are well studied and both around 90% efficient.

The electricity is capable of operating in both the vector and scalar fields, it is the energy conversion bridge.

By having the COP<1 frame of reference produce electricity as its system output I can input that electricity just past TDC 180 degrees and create a gas (with massive volume differential capable of doing work), that is operating in the scalar COP>1 frame of reference.

The system vertical prime vector axis is where the link between COP<1 and COP>1 is made, using electricity as the communication bridge.


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@evolvingape
The problem I see is that even if your proposition worked and even if you gave it all away. The moment a purely electrical machine with moving parts or not came to be it would be render a water based gravity machine pointless. As such I have absolutely no interest in them because even if they did work they would soon be obsolete. Gears and pumps and rotating things or floats is the past.... a device making no sound with no moving parts generating tangible power is the future. I am bound to the future not the past.


AC


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@Smudge
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I don't like your use of the the word "saturate" since that implies we have material that can saturate in the usual sense of the word.  There is no such material there. 

You have the wrong perspective in my opinion because it is too confined. I see things in an absolute sense and use infinite element analysis which is like saying you see the Earth through a telescope as a simple object while I see it through a microscope for what it is. There is material there because a field can only act on another field and in this case the field change acts on the material of the coil causing an increase in current. How else could it act on the coil?.

Quote
As regards where did the input energy go, it appeared as torque doing work and therefore created output energy.  Most of it that is.

The problem I see is you have jumped from an input of moving electrons which carry a field with them to torque on a shaft without including the exact nature of all the steps in between. Sure it appeared as torque however what discrete steps were involved in between?, How, where and why does the process ensure energy is conserved?. The devil is in the details you seem to be just skipping over in broad strokes.

Quote
The remainder was left behind as inductive energy that could be recovered.  The overall COP was unity.  I did not model losses so there was no energy dissipation via that route.

Again your using terms to describe things which don't actually describe anything. For instance how can inductive energy just be left behind?. I mean what is inductance exactly?, what is the nature of inductance?, where was it, where was it going, what was it doing and how in gods name could it be left behind?.


AC



 


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There is material there because a field can only act on another field and in this case the field change acts on the material of the coil causing an increase in current.
Yes, the coil is a material object, however the magnetic flux does not even need to touch its windings in order to induce current in it.

Smudge's objection to the phrase "The PM field saturates the inductor" is valid because the PM's magnetic field has nothing to saturate in an air-coil.
The most a moving PM could do to an air-coil ...is melt it,  but that would be only the result of this coil's imperfections - not its inherent behavior.  
An ideal air-coil does not have resistance nor hysteresis loss and does not heat up.  Anyway, heating is not saturation.

Also, the level of flux alone from the PM is not responsible for the induced current in an active coil. Only the change in flux (ΔΦ) is responsible for that.  The rate of change of flux (dΦ/dt) does not affect the magnitude of the induced current in an ideal active inductor, either.

How else could it act on the coil?.
If you want to understand mechanistically how a magnetic flux can affect a coil without even touching its windings, you'd need to understand what matter is, as well as the intervening Euclidean space and the magnetic flux....and the effect of their temporal interactions on perceived relations in space.
For engineering purposes, it is just enough to know how they behave.

For instance how can inductive energy just be left behind?
In a coil the energy is stored as magnetic field (manifesting as current) and in a capacitor the energy is stored as electric field (manifesting as voltage).
Both are energy storage devices and if you put energy into them, it stays there and in case of the inductor it is left behind as circulating current.

I mean what is inductance exactly?, what is the nature of inductance?
It's a ratio of magnetic flux to current.
If the precise descriptions of their behaviors for engineering purposes, is not enough for you, and you want mechanistic answers to these fundamental physical questions, then study this - it contains the answers you seek.
« Last Edit: 2015-08-28, 16:27:44 by verpies »
   
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