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Author Topic: Controller No5 With Protection - Looking for Explosions  (Read 156800 times)

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It's not as complicated as it may seem...
I was thinking a long time and I could not think of a good reason for this MOSFET to become turned on with the gate shorted to source.

Is it turning on? Might that opposite pulse on the undriven MOSFET and 1k resistor be what's expected if one considers the bifilar coil to be an open-ended transmission line?
   

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It's not as complicated as it may seem...
In 2009 when Peter and I worked on these experiments, the following is some background and suggestions based on the path I followed and results I achieved shortly afterward.

As the test setup consisted of two switches and two coils (in a bifilar configuration), and we found the "pulse" only occurred on the delayed coil, it was hypothesized that we may be able to eliminate one coil. That became the second test configuration, and basically where the collaborative experiments ended as far as I remember.

From here I began working to developing the simulated effect with some success. One key factor was that I surmised the connecting wiring between the coil and DC supply could/should be replaced with a transmission line, aka coax cable. This improved and solidified my results a great deal. In discussing the improvement with Wavewatcher/BEP, he suggested I replace even the coil with a length of coax, and this proved to be a fruitful modification. In fact, best performance was achieved when the two halves of TX line were of the same length. At this point it appeared to me to be a new and novel form of Blumlein/step-recovery-diode hybrid  Pulser. The diode is very important, and the pulses are NOT produced without it. Some diodes work better than others, so I recommend trying a few types.

I found that the second, delayed MOSFET can also be dispensed with, as one MOSFET can do the job. It turned out that once the coax length, DC supply voltage and drive pulse period are "tuned" just right, a 50% duty input pulse will drive the circuit into a form of resonance where the pulses are 5 to 10 times the amplitude of the DC supply voltage, depending on the resulting output pulse width and gate drive period. In theory this circuit might achieve extremely high voltage/narrow pulses from ordinary supply voltages. One might consider this circuit a "tuned voltage compression device", where it converts a regular 50% pulsed DC input, to a proportional v x t pulsed output; the smaller that "t" is, the higher "v" is, so that the input and output v x t is always equal. At any rate, you can see one scope shot here showing the circuit hitting a "resonant" point where the output voltage is multiplied and time-diminished by about the same factor. The attached pics are using a 20V supply voltage.

- sim01 is the two MOSFET setup, with single red and violet gate pulses, and resulting delayed MOSFET drain pulse.

- sim03 is hitting "resonance" with continuous gate drive.

- 2-TX Line Schematic was my final configuration and starting point timing values.
   

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Thanks Poynt for looking into this, but the 1K resistor setup was done later to see what would happen (nothing weird)
when using a 1K instead of the shorted MOSFET.

So the strangeness we see is at the posts roughly between post #412 and 415.

It looks to me in posts 412 and 414 screenshots there is evidence of the shorted MOSFET to turn on looking
at the drain voltage and drain current signals.

Anyway,   nice idea to have the bifilar coil replaced by certain lengths of coax.
The pulses i see without the 50 Ohm protection resistor at the PS are already huge and fast in the bifilar coil
setup, so i can only imagine what they look like with a coax cable and the proper (DSR?)Diode.


Itsu   
   

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In 2009 when Peter and I worked on these experiments, the following is some background and suggestions based on the path I followed and results I achieved shortly afterward.

As the test setup consisted of two switches and two coils (in a bifilar configuration), and we found the "pulse" only occurred on the delayed coil, it was hypothesized that we may be able to eliminate one coil. That became the second test configuration, and basically where the collaborative experiments ended as far as I remember.

From here I began working to developing the simulated effect with some success. One key factor was that I surmised the connecting wiring between the coil and DC supply could/should be replaced with a transmission line, aka coax cable. This improved and solidified my results a great deal. In discussing the improvement with Wavewatcher/BEP, he suggested I replace even the coil with a length of coax, and this proved to be a fruitful modification. In fact, best performance was achieved when the two halves of TX line were of the same length. At this point it appeared to me to be a new and novel form of Blumlein/step-recovery-diode hybrid  Pulser. The diode is very important, and the pulses are NOT produced without it. Some diodes work better than others, so I recommend trying a few types.

I found that the second, delayed MOSFET can also be dispensed with, as one MOSFET can do the job. It turned out that once the coax length, DC supply voltage and drive pulse period are "tuned" just right, a 50% duty input pulse will drive the circuit into a form of resonance where the pulses are 5 to 10 times the amplitude of the DC supply voltage, depending on the resulting output pulse width and gate drive period. In theory this circuit might achieve extremely high voltage/narrow pulses from ordinary supply voltages. One might consider this circuit a "tuned voltage compression device", where it converts a regular 50% pulsed DC input, to a proportional v x t pulsed output; the smaller that "t" is, the higher "v" is, so that the input and output v x t is always equal. At any rate, you can see one scope shot here showing the circuit hitting a "resonant" point where the output voltage is multiplied and time-diminished by about the same factor. The attached pics are using a 20V supply voltage.

- sim01 is the two MOSFET setup, with single red and violet gate pulses, and resulting delayed MOSFET drain pulse.

- sim03 is hitting "resonance" with continuous gate drive.

- 2-TX Line Schematic was my final configuration and starting point timing values.

Hi Poynt

Looking at your circuit, from a layman's point of view, I would say your two pieces of coax are acting as inductors and capacitors all in one. The mosfet switches on and charges the two inductors in series, the mosfet switches off and there is a discharge through the diode to the junction of the two coaxial wires, from this point on the inductive capacitance of the second coax goes into oscillation, being fed by the capacitive charge of the first coax to keep up the voltage.

It is parametric, you changed the inductance  and capacitance with the diode connection, the diode supplied "DC" to the Parallel LC of the second coax cable which then went into oscillation. what is interesting is the "level" of oscillation, not the usual drop to zero.

Regards

Mike


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I know this is an old thread regarding pulse generation for the TPU but I thought that this was the best place for what I'm going to post.  This is also probably ridiculous in light of Mike's current work with his Steap, but I think there may be some value in what I've found.  This discovery was by accident and actually was a problem in my RLE research before I realized what was happening.

Anyway, below is a sim which best demonstrates the concept and that is, when two like coils on a common core [ferrous or air] are charged to dissimilar and opposite currents and then mixed, a relatively large voltage transient is produced that is many times the power supply.  This is a result of the dissimilar currents attempting to reach equilibrium via the turn-turn and/or coil-coil self capacitance. 

In the sim below, L1 serves as a primary and L2 as a secondary.  For the first 10us, L1 is charged from V4, a 50v dc supply, and L2 is shorted via S3 and S4.  The current build up in L2 is -.9 * I(L1) and in this case the peak currents at 10us are L1 = .521 and L2 = .468 .  At the end of 10us, VL1 is grounded via S1, and VL2 along with the dot end of L2 are released.  This forces the currents in L1 an L2 to attempt to equalize via their internal 20pf capacitance's, and the result is the 2.1kv pulse generated at L2.  Also note that the currents reverse in L1 and L2 at this time. 

In this version, the bucking currents in L1 and L2 are discharged into Vs and returned to the supply V4.  This reduces the effective energy from the supply to a relatively low level and in this case it is 6.14uJ .

The amplitude and duration of the voltage pulse is dependent on the coupling factor of the coils and their capacitance's plus the current levels.

I will attempt to apply this technique to some of the orthogonal TPU setups I have laying around to see what may result after simulating some of the modeled TPU coils.

Regards,
Pm

 
« Last Edit: 2022-11-01, 23:12:39 by partzman »
   
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This version has L1 and L2 combined in the "aid" mode by reversing L2 rather than the buck mode in the previous sim.  The method of operation is slightly different and the peak voltage reached is less.

One thing to note is the peak reactive power in L1 of 233.5 watts.  Another is the ratio of the average reactive power of 12.252 watts to the average input power of .216 watts which is 56.7:1 .

It is my opinion that SM's TPU is basically a 'reactive' to 'real' power converter and that is the reason for the high heat generation.  It does not matter what creates the electron flow in the device, but the resultant reactive power is many times greater than the real power generated thus creating heat problems.

Pm



   
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I know this is an old thread regarding pulse generation for the TPU but I thought that this was the best place for what I'm going to post.  This is also probably ridiculous in light of Mike's current work with his Steap, but I think there may be some value in what I've found.  This discovery was by accident and actually was a problem in my RLE research before I realized what was happening.

Anyway, below is a sim which best demonstrates the concept and that is, when two like coils on a common core [ferrous or air] are charged to dissimilar and opposite currents and then mixed, a relatively large voltage transient is produced that is many times the power supply.  This is a result of the dissimilar currents attempting to reach equilibrium via the turn-turn and/or coil-coil self capacitance. 

In the sim below, L1 serves as a primary and L2 as a secondary.  For the first 10us, L1 is charged from V4, a 50v dc supply, and L2 is shorted via S3 and S4.  The current build up in L2 is -.9 * I(L1) and in this case the peak currents at 10us are L1 = .521 and L2 = .468 .  At the end of 10us, VL1 is grounded via S1, and VL2 along with the dot end of L2 are released.  This forces the currents in L1 an L2 to attempt to equalize via their internal 20pf capacitance's, and the result is the 2.1kv pulse generated at L2.  Also note that the currents reverse in L1 and L2 at this time. 

In this version, the bucking currents in L1 and L2 are discharged into Vs and returned to the supply V4.  This reduces the effective energy from the supply to a relatively low level and in this case it is 6.14uJ .

The amplitude and duration of the voltage pulse is dependent on the coupling factor of the coils and their capacitance's plus the current levels.

I will attempt to apply this technique to some of the orthogonal TPU setups I have laying around to see what may result after simulating some of the modeled TPU coils.

Regards,
Pm

Can you upload the LTspice File? Pulsing coils with high voltage nanosecond pulses like AVEC / TPU devices is also my area of interest. I'm looking for practical ways to achive this expecially the delayed HV pulse on bifilar coils.
   
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This is a sim with the buck mode applied to a symmetrical transmission line that was modeled from a bench design.  Peak pulse is ~500v with a 143ns width.

Pm
   
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Can you upload the LTspice File? Pulsing coils with high voltage nanosecond pulses like AVEC / TPU devices is also my area of interest. I'm looking for practical ways to achive this expecially the delayed HV pulse on bifilar coils.

Sure, see the .asc file below.

Pm
   

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What happens if the coils are not bucking, but boosting (wound same direction).

The bifilar coils used by Peter were wound as a pair in the same direction.
   
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What happens if the coils are not bucking, but boosting (wound same direction).

The bifilar coils used by Peter were wound as a pair in the same direction.

My post #430 has the discharge currents in L1 and L2 aiding but the charging of L1 and L2 is still done in a buck mode so I don't think this is the same as Peter's arrangement.  I'll have to scan back thru this thread to see Peter's arrangement to be sure.

I will assume [without testing at this point] that the bucking pulse produced in post #429 would not normally induce an orthogonal coil while the aiding pulse produced in post #430 should.  IOW, a pair of wires with many turns toroidally wound over a horizontal coil should act as  single turns when pulsed as a symmetrical transmission line as in post #432.  This is pure speculation on my part at this point and I hope to prove this or not over the next few days.

Pm
   
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Grumpy,

I did a quick but focused look thru this thread and IMO, the pulsing of the bifilar coils by Peter and others that were done in various physical and electrical configurations with delayed pulse timings, had instances where the conditions I describe above were met and large pulses were generated.  I could be wrong of course!

What I don't quite understand because I haven't read all the TPU threads is, what was the application of these high level pulses in the TPU?

Pm
   

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Grumpy,

I did a quick but focused look thru this thread and IMO, the pulsing of the bifilar coils by Peter and others that were done in various physical and electrical configurations with delayed pulse timings, had instances where the conditions I describe above were met and large pulses were generated.  I could be wrong of course!

What I don't quite understand because I haven't read all the TPU threads is, what was the application of these high level pulses in the TPU?

Pm

You apply the pulses in a circular sequence to produce a rotating field.
This requires the pulses to also interact with either a static magnetic field or have a positive DC offset (bias).
This rotating field will have the inductive properties of a rotating magnetic field and also the inductive properties of a rotating displacement field. 
(Imagine that you pattern space as a magnetic field and then rotate the space.)
You then use a capacitive or inductive output coil.
The inductive output coil cannot be the same direction as the input coils, but should be orthogonal, else it reflects back and doesn't work.

As far as know, no one has applied this pulse properly to date, except Centraflow, and his method is complex.
   
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You apply the pulses in a circular sequence to produce a rotating field.
This requires the pulses to also interact with either a static magnetic field or have a positive DC offset (bias).
This rotating field will have the inductive properties of a rotating magnetic field and also the inductive properties of a rotating displacement field. 
(Imagine that you pattern space as a magnetic field and then rotate the space.)
You then use a capacitive or inductive output coil.
The inductive output coil cannot be the same direction as the input coils, but should be orthogonal, else it reflects back and doesn't work.

As far as know, no one has applied this pulse properly to date, except Centraflow, and his method is complex.

OK, thanks for that explanation.  My question then becomes how can we have conventional induction with orthogonal coil arrangements?  IIRC, my experiments with an orthogonal TPU topology resulted in the voltages produced in the toroidal primary windings to appear as a single turn to the secondary orthogonal winding.  However I wasn't using high voltages.

I am familiar with Centraflow's design and it is indeed complex.  I understand he calls it a plasma ion/electron conversion but the voltages are too low for plasma generation in air!?

BTW, I do believe in an active aether teeming with energy.

Pm
   

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OK, thanks for that explanation.  My question then becomes how can we have conventional induction with orthogonal coil arrangements?  IIRC, my experiments with an orthogonal TPU topology resulted in the voltages produced in the toroidal primary windings to appear as a single turn to the secondary orthogonal winding.  However I wasn't using high voltages.

I am familiar with Centraflow's design and it is indeed complex.  I understand he calls it a plasma ion/electron conversion but the voltages are too low for plasma generation in air!?

BTW, I do believe in an active aether teeming with energy.

Pm

If proven, (devices are still being built to verify claims) I believe it will be a sort of Wilson Effect where space is rotated rather than a solid dielectric.
This also means that the explanation that SM provided about a rotating magnetic field is not entirely accurate.  Spherics called it "magnetic like", but also commented not to use blocks of delectric materials in the rotating area and to leave it as open as possible.
   
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If proven, (devices are still being built to verify claims) I believe it will be a sort of Wilson Effect where space is rotated rather than a solid dielectric.
This also means that the explanation that SM provided about a rotating magnetic field is not entirely accurate.  Spherics called it "magnetic like", but also commented not to use blocks of delectric materials in the rotating area and to leave it as open as possible.

OK I understand.  Will be anxious to hear any results you have with your Spherics build!

Pm
   
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A current is a number of charges that flow per unit time. They are usually produced by a current in a conductor, but they can also be produced by moving a charged conductor or dielectric. The simplest case is a charged ring that rotates: it obviously creates a magnetic field since we have charges that rotate, it's a known fact. The current is usually small since the number of rotating charges is what the device can carry as a capacitor, so for example 10µC if the capacitance of the ring is 1 nF charged at 10 KV, which gives a current of 1 mA if the ring rotates at 100 revolutions per second.

All the effects in the Grumpy's picture above , not necessarily easy to implement experimentally for significant measurable effect, seem to me to be real and to be the simple consequence of these currents linked to the mechanical displacement of charges, and the reciprocal effects.


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A current is a number of charges that flow per unit time. They are usually produced by a current in a conductor, but they can also be produced by moving a charged conductor or dielectric. The simplest case is a charged ring that rotates: it obviously creates a magnetic field since we have charges that rotate, it's a known fact. The current is usually small since the number of rotating charges is what the device can carry as a capacitor, so for example 10µC if the capacitance of the ring is 1 nF charged at 10 KV, which gives a current of 1 mA if the ring rotates at 100 revolutions per second.

All the effects in the Grumpy's picture above , not necessarily easy to implement experimentally for significant measurable effect, seem to me to be real and to be the simple consequence of these currents linked to the mechanical displacement of charges, and the reciprocal effects.

The need for polarization by a magnetic field or an electric field is interesting.
   
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This is the aiding current version of the buck pulse generator with various bias currents in L2 prior to the cycle starting.  I should add that D3 clamps VL2 so that only a unidirectional pulse is generated.  If D3 is removed, bipolar pulses will be generated.  Also, the reverse voltage in the sim is far greater than D3 would normally handle, but the model for this particular diode does not include reverse breakdown.  In an operational circuit, D3 would obviously have HV ratings.

As can be seen from the table, the peak voltage on VL2 increases with increasing L2 bias current.  A 400ma bias is shown and what is also interesting is the net energy consumption.  We see 17.512uJ drawn from the supply V4 and at the end of the cycle, IL2 is 0.0ma and IL1 is 406.87ma resulting in a gain over the starting bias of (.40687^2-.400^2)*.005/2 = 13.858uJ .  This makes for a net energy consumed of only 3.654uJ !

Pm
   

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What kind of switches are in the sim?
   
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What kind of switches are in the sim?

They are voltage controlled switches with a threshold of zero volts which means the switching voltage varies from +1 for "on" to -1 for "off".  The on resistance is specified at .05 ohm in this case.  They have unlimited voltage and current and also do not have any mosfet capacitance's such as Ciss or Coss.  With a relatively small Coss at VL2, circuit performance is not degraded.

In the case of the unipolar single pulse generators shown with a mosfet replacing S4, the BVdss rating should be greater than the maximum peak voltage on VL2 and D3 would be the substrate or body diode.

Pm
   
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