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Author Topic: Parametric Charging  (Read 44040 times)

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In the Revised schematic if you were to include the
MosFet Body Diodes in the diagram what would you
have?


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For there is nothing hidden that will not be disclosed, and nothing concealed that will not be known or brought out into the open.
   

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PM

thanks for this revised schematic, it now clearly shows that the "input" is being measured "behind" the MOSFET driver stage.

So the input / output measurement is only done for that part behind the driver stage.

This makes it hard to create a feedback loop as the "input" is pulsed DC (square wave 50% duty cycle) and the output is DC.

If we include the FG and MOSFET driver stage then the input would be 100 times higher, see my post #259.
Perhaps we can reduce that significantly by using Peterae's mentioned circuit in his post #261.
I am waiting for the correct parts to try that.


Itsu


   
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In the Revised schematic if you were to include the
MosFet Body Diodes in the diagram what would you
have?

What you would have and actually do have, is a half wave rectification of a unipolar pulse charging a capacitor.  The difference is that the parametric capacitance of the mosfets provides the "C" that resonates with L1.  It is considered that this parametric capacitance is the gain mechanism for the device.

Previously shown full wave circuits are actually more efficient but this circuit is the easiest to replicate IMO.

Pm
   
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PM

thanks for this revised schematic, it now clearly shows that the "input" is being measured "behind" the MOSFET driver stage.

So the input / output measurement is only done for that part behind the driver stage.

This makes it hard to create a feedback loop as the "input" is pulsed DC (square wave 50% duty cycle) and the output is DC.

If we include the FG and MOSFET driver stage then the input would be 100 times higher, see my post #259.
Perhaps we can reduce that significantly by using Peterae's mentioned circuit in his post #261.
I am waiting for the correct parts to try that.


Itsu

Itsu,

Yes, this is the challenge that is, to produce an efficient input switching circuit that is powered by the charge on C1.  Several things that might help in this is to add additional paralleled mosfets to increase the available parametric charge while at the same time lower the frequency.

Increasing the pulse amplitude can also be experimented with but sometimes can actually prove to be detrimental depending on the delta C of the particular mosfet(s) used.


Pm
   
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Fantastic work!

Either a gremlin to find or an effect to discover

Something that may be relevant from my experience  using metal detectors where you spend many hours bush walking and listening to out of range signals which mean either a metal target or a ground variance which is  usually a difference in water content. There is however a certain interference that affect detectors of the pulse induction kind i use where they become  almost unusable for many hours at a time ,and on these days there is often a random fully saturated signal which stops you in your tracks and always, in hindsight is a ghost signal.

On a good day these ghost signals still occour but far less often.

A metal detector coil is 300uh +/- 10% they send pulses out and immediately switch to recieve after every pulse train looking for delayed eddy currents that metal objects leave behind .They are from 8" to 30" in diamater air core and use litz wire .

These coils also incorporate a faraday shield which i think i see as alluminium foil on the ftpu.
Without the faraday shield they are erratic and not useable at all near the ground .
That faraday shield is a full turn of conductive foil enclosing the whole  coil like a shield which is joined to ground on one end but does not complete a full turn(2mm gap )which would short the coil.

I have never been able to predict that random signal but if there is agreement among detector users that  this interference is called "shperics" and could be worth study .

If it is the semiconductors or the coil it may be worth changing the coils topology ,which i will do after im at first base .

If course we all would like it to be the coil and its environment!

Back on topic ,
I am keen to replicate .
Does any body have an economic source for the 14n05L?
Or are fast diodes the only requirement?
the other bits i have .
The 609p1 mosfer driver also seems to be elusive  but there are other described methods.
Replicating needs to be as exact as possible to be of the most worth.
I live in Tinmans neck of the woods.

3D
   

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Here a few pictures of my present setup using a breadboard.

I lost some MOSFET drivers as can be seen by the scorch marks, they do not like a too high frequency at 40V with
this L1 as a load.    I have some copper tape as heatsink on now.

The covered part in the middle of picture 1 are some additional parts (see Peterae his post #261) not being used yet.

 
Guess the pictures speak for them self.
I do have extra Bat 42 schottky diodes across the source/drain of the MOSFETs

The RFD14N05L MOSFETs came from Ebay (Germany, which is close from here).

Itsu
   
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Fantastic work!

Either a gremlin to find or an effect to discover

Something that may be relevant from my experience  using metal detectors where you spend many hours bush walking and listening to out of range signals which mean either a metal target or a ground variance which is  usually a difference in water content. There is however a certain interference that affect detectors of the pulse induction kind i use where they become  almost unusable for many hours at a time ,and on these days there is often a random fully saturated signal which stops you in your tracks and always, in hindsight is a ghost signal.

On a good day these ghost signals still occour but far less often.

A metal detector coil is 300uh +/- 10% they send pulses out and immediately switch to recieve after every pulse train looking for delayed eddy currents that metal objects leave behind .They are from 8" to 30" in diamater air core and use litz wire .

These coils also incorporate a faraday shield which i think i see as alluminium foil on the ftpu.
Without the faraday shield they are erratic and not useable at all near the ground .
That faraday shield is a full turn of conductive foil enclosing the whole  coil like a shield which is joined to ground on one end but does not complete a full turn(2mm gap )which would short the coil.

I have never been able to predict that random signal but if there is agreement among detector users that  this interference is called "shperics" and could be worth study .

If it is the semiconductors or the coil it may be worth changing the coils topology ,which i will do after im at first base .

If course we all would like it to be the coil and its environment!

Back on topic ,
I am keen to replicate .
Does any body have an economic source for the 14n05L?
Or are fast diodes the only requirement?
the other bits i have .
The 609p1 mosfer driver also seems to be elusive  but there are other described methods.
Replicating needs to be as exact as possible to be of the most worth.
I live in Tinmans neck of the woods.

3D

3D,

Try Mouser for the mosfets and Ixys drivers.  They have the 14N05L's for $0.82 in singles or $0.68 in 10 piece quantities.  The Ixys drivers are available in 604, 609, and 614 which are 4, 6, and 9 amp devices respectively.  They also come optionally with enable or inverted output and any of these will work for the driver although they are not very efficient for driving continuous loads.

Also, ordinary slow recovery diodes will work but at higher frequencies due to their higher reverse capacitance.  Fast recovery diodes will not work well if at all.

Pm
   
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Here a few pictures of my present setup using a breadboard.

I lost some MOSFET drivers as can be seen by the scorch marks, they do not like a too high frequency at 40V with
this L1 as a load.    I have some copper tape as heatsink on now.

The covered part in the middle of picture 1 are some additional parts (see Peterae his post #261) not being used yet.

 
Guess the pictures speak for them self.
I do have extra Bat 42 schottky diodes across the source/drain of the MOSFETs

The RFD14N05L MOSFETs came from Ebay (Germany, which is close from here).

Itsu

Itsu,

Thanks for posting your pix.  I also find it interesting that in using the Bat 421 diodes across the mosfets and you achieved a higher COP than I did without using any bypass diodes.  These apparently are increasing the forward conduction efficiency as compared to the 14N05L's substrate diodes.

Pm
   

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It's not as complicated as it may seem...
PM

thanks for this revised schematic, it now clearly shows that the "input" is being measured "behind" the MOSFET driver stage.

So the input / output measurement is only done for that part behind the driver stage.

This makes it hard to create a feedback loop as the "input" is pulsed DC (square wave 50% duty cycle) and the output is DC.

If we include the FG and MOSFET driver stage then the input would be 100 times higher, see my post #259.
Perhaps we can reduce that significantly by using Peterae's mentioned circuit in his post #261.
I am waiting for the correct parts to try that.


Itsu

I'm a little confused by your post Itsu, and I'm not 100% clear on PM's revised schematic.

What I see on the schematic, is an input voltage measurement (CH1, YEL), and in the previous schematic there was a current probe on the input. It appears the revised schematic is now using a CVR (CH4 voltage) at the output end of the circuit to provide the input current measurement, is this correct PM? (CH2-CH4 also provides for the voltage across Rload for Pout). Pin is computed via CH1 x CH4?

btw PM, does the sim show COP>1? Also, is the Pin result the same in the sim regardless if i(in) is taken at L1 or R1?
   

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poynt99,

PM has stated earlier that both the current probe measurement taken just behind the CH1 (yellow) point should
give the same value as the CVR (1 ohm / 10 ohm) measurement.

This was confirmed by me and viewable in this post here:
http://www.overunityresearch.com/index.php?topic=3655.msg69766#msg69766

Purple is the CVR (10 Ohm in my case) trace, while green is the current probe trace.


In keeping the circuit replicable for many, i think PM has opted for the CVR only.

Itsu
   
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I'm a little confused by your post Itsu, and I'm not 100% clear on PM's revised schematic.

What I see on the schematic, is an input voltage measurement (CH1, YEL), and in the previous schematic there was a current probe on the input. It appears the revised schematic is now using a CVR (CH4 voltage) at the output end of the circuit to provide the input current measurement, is this correct PM? (CH2-CH4 also provides for the voltage across Rload for Pout). Pin is computed via CH1 x CH4?

btw PM, does the sim show COP>1? Also, is the Pin result the same in the sim regardless if i(in) is taken at L1 or R1?

Poynt,

An LtSpice simulation yields similar results as a cloudy, rainy day in my location that is, less than unity efficiency but tweaking the sim frequency can yield efficiencies in the 98-99% range however.

Pm
   
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I would like to add several points that I have discovered:

1)  During "optimal" days with clear skies and sunshine, placing a tinfoil covered cardboard box shield over the circuitry actually improved the COP!? 

2)  I have found that even on cloudy, rainy days, very careful tuning downwards in frequency to achieve the lowest frequency possible prior to the sudden increase in the voltage across C1 can yield apparent COP's>1.  This may not always be the case but at present our skies are overcast and the humidity is 100% with no rain falling and I can see COPs in the 1.15-1.25 range.

3)  An increase in the inductance of L1 seems to soften or broaden the critical low frequency "break over" point.

Pm
   
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All,

A test I've wanted to run for some time but have put off until now turns out to be quite interesting!  It simply involves replacing the parametric capacitance device with a fixed capacitor paralleled by a schottky diode as shown below in the schematic.  This scheme is now just "resonant" charging and seems to be able to provide smaller amounts of gain with tweaking. 

I would like to add that this test was run immediately following a scope input re-calibration on the Tek MDO. 

The advantage of this resonant charging verses the parametric version is it's ability to produce a greater voltage across C1 than the supply resulting in higher output power levels.  The disadvantage at this point appears to be a much lower available gain.

The scope pix shows the input power pin to be 373.6mw mean and pout = 54.99^2/7.451e3 = 405.8mw.  The apparent COP = 405.8/373.6 = 1.086 .  This is low enough to be measurement error but I think it is worth pursuing to attempt higher gains and at lower frequencies. 

Regards,
Pm

   
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All,

Well, perhaps just plain resonant charging has some merit!  The following is a charge sweep (for lack of a better term) of C1 over 100ms using the circuitry in the attached schematic seen below.  L1 and C2 have been increased in value which results in an operating frequency of 62kHz.

The scope shot below shows the measurements at the 30.05ms mark in the charge sweep and from this we can determine the energy levels.  The output voltage across C1 reaches 50.41 volts so Uout = 50.41^2 * 3.94e-6/2 = 5.006mJ .  The input power required to raise C1 to this level is seen to be 104.8mw which equates to an input energy of Uin = 104.8e-3 * 30.05e-3 = 3.147mJ.   

Therefore, the apparent COP = 5.006/3.147 = 1.59 .

If this is reasonably accurate and can be replicated, there should theoretically be no lower limit in frequency nor any limit in power output.

Regards,
Pm

Edit: I will add that the scope was in the hi-res mode (16 bit) with the sweep rate at 100Ms/S.
   
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   I like the simplified design.

   Trying to catch up; would you kindly explain: "The scope pix shows the input power pin to be 373.6mw mean ".

   Also, what is the current determined from the 1-ohm R1 and how is it used?
   
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Hi Pm,

The question is how this latest setup behaves (input and output energy wise) when a real load is applied across C1?

Because at present there is no load and the stored energy in C1 is 'idle'.  I would compare it to a flywheel which has no mechanical load on it, just a small amount of friction and / or air drag.

Gyula
   
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   I like the simplified design.

   Trying to catch up; would you kindly explain: "The scope pix shows the input power pin to be 373.6mw mean ".

   Also, what is the current determined from the 1-ohm R1 and how is it used?

The answer to both your questions is, the current measured by R1 or the CSR on CH4(grn) is multiplied by the voltage on CH1(yel) at every instantaneous point in time and summed to produce the average or mean power integral of 373.6mw which is the power input to the circuit.

Pm
   
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Hi Pm,

The question is how this latest setup behaves (input and output energy wise) when a real load is applied across C1?

Because at present there is no load and the stored energy in C1 is 'idle'.  I would compare it to a flywheel which has no mechanical load on it, just a small amount of friction and / or air drag.

Gyula

Gyula,

It is true there is no load and your flywheel analogy is close but not quite accurate.  In this case, the energy to spin the flywheel up to a given speed is less than the energy contained in the spinning flywheel at that given speed.   

IOW, we spend less energy to charge C1 than the energy contained in C1.  We could use this circuit in continuous charge/discharge cycles to do work with gain.

I will do an analysis of the charge sweep in order to determine the ideal load resistance that will produce the maximum COP running continuously and will post the results later.

Pm
   
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All,

Here is an analysis of the circuit shown in the schematic in post #288. 

The first scope pix shows the charge sweep which is averaged over 8 samples during a 100ms horizontal sweep at a 100Ms/S sweep rate.  The vertical cursors are placed at .905ms and 20.07 ms respectively resulting in a dt of 19.17ms.  The respective voltage levels across C1 at these positions are 36.85v and 49.45v therefore, the resultant dU or differential energy in C1 between the cursors is (49.45^2-36.85^2) * 3.94e-6/2 = 2.142mJ.  The equivalent power for this time period is then 2.142e-3/19.17e-3 = 111.7mw . 

The mean or average voltage across C1 between the cursors is seen to be 45.22v so the ideal load resistance across C1 for continuous running would be 45.22^2/111.7e-3 = 18.3k ohm. 

We also see the input power consumed between the cursors at 99.28mw so the gain is 111.7/99.28 = 1.125 .  We would expect this to be the gain in continuous running at 62kHz with an 18.3k load.

The next scope pix shows the circuit running continuously with an 18.51k load across C1 which was the closest value on hand.  As can be seen , the output voltage across C1 and the load is 45.69v resulting in a pout = 45.69^2/18.51e3 = 112.8mw .  The Math channel calculation shows the pin to be 94.05mw resulting in an apparent COP = 112.8/94.05 = 1.20 which is higher than predicted from the charge sweep.  I'm not sure why the difference at this point in time.

Note the close correlation between the charge sweep analysis and the continuous running data.  IMO, this shows the importance of running charge sweeps to determine the performance and optimized load requirements for given circuit parameters.  From what TK has stated, Rigol scopes have the capability of 50Ms/S scan rates for 100ms sweeps and should be greater for faster sweep rates.  The important thing is to capture the charge slope so it can be analyzed.

Regards,
Pm
   
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Looks promising but my trust in dso's higher functions has been low ever since the Rosemary incident ,many thanks to Poynt on that one.
Im not suggesring that you are in error ,your insights have got me off my arse !

All parts comming ..2 weeks away ...

I wonder if changing the coil topology ( like 22turns at 18" diameter,300uh ) has any effect on the results?

Does having the semis in the centre as opposed to outside make tuning easier?

3D

   

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It's not as complicated as it may seem...
Looks promising but my trust in dso's higher functions has been low ever since the Rosemary incident ,many thanks to Poynt on that one.
Im not suggesring that you are in error ,your insights have got me off my arse !

All parts comming ..2 weeks away ...

I wonder if changing the coil topology ( like 22turns at 18" diameter,300uh ) has any effect on the results?

Does having the semis in the centre as opposed to outside make tuning easier?

3D

L,

It wasn't the DSO or it's higher functions that became the nemesis for the RA team, it was their lack of understanding of the over all picture pertaining to the apparatus they were testing/measuring. Their scope performed flawlessly, but the assumptions made regarding their measurement points and methods is what ultimately led them down the garden path.
   
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...
I wonder if changing the coil topology ( like 22turns at 18" diameter,300uh ) has any effect on the results?
...

3D

  Interesting question.   18" diameter is huge...

 I wonder if you (PM) could show us a photo of your coil or inductor, with a ruler or something to show the size? 
   
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L,

It wasn't the DSO or it's higher functions that became the nemesis for the RA team, it was their lack of understanding of the over all picture pertaining to the apparatus they were testing/measuring. Their scope performed flawlessly, but the assumptions made regarding their measurement points and methods is what ultimately led them down the garden path.

Let's not forget the massive amount of outright lying that was emitted by RA.

If she had simply acknowledged the truth from the beginning --- that the original 555 circuit did not produce the duty cycle she thought it did but rather the exact inversion --- nobody would have been interested at all. But her lies percolated and even infected the principals at EF (not hard to do).

Sorry about the "off topic" but whenever I see Ainslie's folly blamed simply on measurement misunderstandings and errors... I have to point out the deliberate lying and obfuscation that contributed greatly to the "Ainslie" phenomenon.

I haven't heard from her in many months. I wonder if she's still alive. Lots of people aren't.
« Last Edit: 2018-10-02, 04:35:13 by TinselKoala »
   
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It's turtles all the way down
For those that have some time to tinker, and based on PM's research, I submit this first draft of a stand alone looped device with self oscillating feature.

I have not got the time to test it on the bench but am sure it can be made to self oscillate if the coupled inductor gain is sufficient.

The IXD601 device data sheet states a max logic input current of  only 10 uA,so the input drive should not load the output coil very much.

Whether it will work without the starter circuit as a self powered unit is another matter.
« Last Edit: 2018-10-02, 14:18:19 by ion »


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"Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy
   
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Looks promising but my trust in dso's higher functions has been low ever since the Rosemary incident ,many thanks to Poynt on that one.
Im not suggesring that you are in error ,your insights have got me off my arse !

All parts comming ..2 weeks away ...

I wonder if changing the coil topology ( like 22turns at 18" diameter,300uh ) has any effect on the results?

Does having the semis in the centre as opposed to outside make tuning easier?

3D

3D,

Hmmm, this would be an interesting experiment using a large diameter coil for L1 and placing a higher frequency parametric circuit in the center!  I will try this and focus on one of Dr. Stiffler's lattice formula frequencies.

Regards,
Pm
   
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