Author Topic: Concern about blocking diode / Zener  (Read 2852 times)

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Concern about blocking diode / Zener
« on: August 05, 2012, 03:51:18 am »
In every simulation I have done, once a blocking diode is introduced into a tuned resonant circuit resonance more or less stops.  Not only does resonance stop, but the wave forms on both sides of the cell become synchronized in parallel rather than mirrored.  Additionally, the peak voltage on the cell goes from as high as 20kV down to about 200V when the blocking diode is in the circuit.

1.  I have to wonder:
  a) what the blocking diode is really meant to do
  b) if the blocking diode is really even necessary

2.  In the simulation one of the last things I have tried to make resonance work with the blocking diode is to put a second capacitor in the VIC circuit which connects the chokes to each other on the side away from the cell, and is around quadruple the value of the cell itself.   The value of this second capacitor seems to have no effect on the calculated resonant frequency, and allows the cell now to resonate with the blocking diode in place in the normal position.  The peak voltage on the cell doesn't come near the peak voltage without the diode, but does about double the peak voltage it would otherwise reach without it.

I'd really like to know if anyone else has tried these scenarios without the blocking diode.  It seems to me with all my simulations that the highest voltage only occurs with unrectified AC current at resonance. 

TS
« Last Edit: August 27, 2012, 23:42:17 pm by timeshell »

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Re: Concern about blocking diode / Zener
« Reply #1 on: August 27, 2012, 23:09:21 pm »
In every simulation I have done, once a blocking diode is introduced into a tuned resonant circuit resonance more or less stops.  Not only does resonance stop, but the wave forms on both sides of the cell become synchronized in parallel rather than mirrored.  Additionally, the peak voltage on the cell goes from as high as 20kV down to about 200V when the blocking diode is in the circuit.

Today I had an inspiration.  I tried changing the "blocking diode" in the VIC in my simulator to a zener diode, Forward Voltage @1A at 100mV.  In doing this, I was able to get the resonant action to return in the circuit where it was lost with the normal diode.  Obviously this is because of the reverse current, but is it possible that the zener diode would block sufficient flow to prevent the circuit from becoming a dead short condition it would otherwise be in without the diode?

I'd love to hear some thoughts/experience on this.

TS
« Last Edit: August 27, 2012, 23:42:31 pm by timeshell »

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Re: Concern about blocking diode / Zener
« Reply #2 on: August 28, 2012, 11:48:19 am »
In every simulation I have done, once a blocking diode is introduced into a tuned resonant circuit resonance more or less stops.  Not only does resonance stop, but the wave forms on both sides of the cell become synchronized in parallel rather than mirrored.  Additionally, the peak voltage on the cell goes from as high as 20kV down to about 200V when the blocking diode is in the circuit.

1.  I have to wonder:
  a) what the blocking diode is really meant to do
  b) if the blocking diode is really even necessary

2.  In the simulation one of the last things I have tried to make resonance work with the blocking diode is to put a second capacitor in the VIC circuit which connects the chokes to each other on the side away from the cell, and is around quadruple the value of the cell itself.   The value of this second capacitor seems to have no effect on the calculated resonant frequency, and allows the cell now to resonate with the blocking diode in place in the normal position.  The peak voltage on the cell doesn't come near the peak voltage without the diode, but does about double the peak voltage it would otherwise reach without it.

I'd really like to know if anyone else has tried these scenarios without the blocking diode.  It seems to me with all my simulations that the highest voltage only occurs with unrectified AC current at resonance. 

TS

You won't get resonance with the Stanley Meyer circuit. It is basically this circuit: http://www.richieburnett.co.uk/dcreschg.html and designed to double the voltage coming out of the transformer. If you look into the tech brief you'll see that he starts with explaining voltage across inductor and capacitor with
Vc = 1/(omega*C) and Vl=omega*L
This would only be currect for alternating current with a waveform of the type
V(t)=V0*cos(omega*t+phi)
However he is using a custom waveform and therefore voltage across those elements cannot be calculated this way anymore. Either he didn't know better or the resonance thing does not apply to a resonant circuit in the traditional way. He's using a form of boost converter to step up the voltage.



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Steve: Is it possible to have something like http://custom.simplemachines.org/mods/index.php?mod=1111 in this forum for being able to post formulas?

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Re: Concern about blocking diode / Zener
« Reply #3 on: August 28, 2012, 12:38:24 pm »
In every simulation I have done, once a blocking diode is introduced into a tuned resonant circuit resonance more or less stops.  Not only does resonance stop, but the wave forms on both sides of the cell become synchronized in parallel rather than mirrored.  Additionally, the peak voltage on the cell goes from as high as 20kV down to about 200V when the blocking diode is in the circuit.

Today I had an inspiration.  I tried changing the "blocking diode" in the VIC in my simulator to a zener diode, Forward Voltage @1A at 100mV.  In doing this, I was able to get the resonant action to return in the circuit where it was lost with the normal diode.  Obviously this is because of the reverse current, but is it possible that the zener diode would block sufficient flow to prevent the circuit from becoming a dead short condition it would otherwise be in without the diode?

I'd love to hear some thoughts/experience on this.

TS

Its equivalent to have a non equalized combination of antiparallel diodes... or combinations of diodes with passive components...

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Re: Concern about blocking diode / Zener
« Reply #4 on: August 28, 2012, 13:18:35 pm »
In every simulation I have done, once a blocking diode is introduced into a tuned resonant circuit resonance more or less stops.  Not only does resonance stop, but the wave forms on both sides of the cell become synchronized in parallel rather than mirrored.  Additionally, the peak voltage on the cell goes from as high as 20kV down to about 200V when the blocking diode is in the circuit.

1.  I have to wonder:
  a) what the blocking diode is really meant to do
  b) if the blocking diode is really even necessary

2.  In the simulation one of the last things I have tried to make resonance work with the blocking diode is to put a second capacitor in the VIC circuit which connects the chokes to each other on the side away from the cell, and is around quadruple the value of the cell itself.   The value of this second capacitor seems to have no effect on the calculated resonant frequency, and allows the cell now to resonate with the blocking diode in place in the normal position.  The peak voltage on the cell doesn't come near the peak voltage without the diode, but does about double the peak voltage it would otherwise reach without it.

I'd really like to know if anyone else has tried these scenarios without the blocking diode.  It seems to me with all my simulations that the highest voltage only occurs with unrectified AC current at resonance. 

TS

You won't get resonance with the Stanley Meyer circuit. It is basically this circuit: http://www.richieburnett.co.uk/dcreschg.html and designed to double the voltage coming out of the transformer. If you look into the tech brief you'll see that he starts with explaining voltage across inductor and capacitor with
Vc = 1/(omega*C) and Vl=omega*L
This would only be currect for alternating current with a waveform of the type
V(t)=V0*cos(omega*t+phi)
However he is using a custom waveform and therefore voltage across those elements cannot be calculated this way anymore. Either he didn't know better or the resonance thing does not apply to a resonant circuit in the traditional way. He's using a form of boost converter to step up the voltage.



_
Steve: Is it possible to have something like http://custom.simplemachines.org/mods/index.php?mod=1111 in this forum for being able to post formulas?


That mod is not ready for my current forum version 2.0.2. It might work. Must run some tests with it.

The burnett circuit looks great. I tried it once. It works, also in comby with a fuelcell.
However, no miracle production.
By creating more volts across the cell, the cell will consume more amps.
Maybe, but i didnt check it, you will have some phase difference.
So, first a voltage peak, followed by current.

Steve