### Author Topic: Restrict Amps with Source Voltage Amplitude  (Read 8098 times)

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##### Restrict Amps with Source Voltage Amplitude
« on: January 04, 2013, 05:48:23 am »
There are a couple things I would like to add to this thread.
1)  As I'm sure most of you know that if you over charge the coils, they will pull more current. A coil operates the opposite way a of a capacitor, where as while charging a capacitor the current starts off high and then current drops as a capacitor reaches 5 Time Constants. An inductor starts off with low current and the current rises and peaks as you reach 5 Time Constants. So you don't want to over charge the coils or you will get high currents. You want to stop charging the coils before it reaches 5TC.

I've read your comments about this in the past.  While I understood what you meant by this, I didn't fully understand how to apply it.

A couple days ago I blew up the transistors in my power supply (again) so have been without my  power source.   I picked up some transistors today to repair it but it was late by the time I got home.  Simply for curiosity sake, I plugged a pair of 9V in series (18V) into the circuit to power it.  I got a result I was not expecting that may be of interest.

I had more gas production at 5 mA than I would normally have using my power supply.   In fact usually I have almost no production whatsoever at 5 mA.  Although the production wasn't very significant it was definitely more than I usually have.

My usual power supply is a 35 amp power supply usually drawing about 3 A through my experiments with the same coils.  Obviously a 9V battery cannot put out 3 A.  I interpret my results to mean that up until now I have been over-saturating my coils with current, limiting its ability to allow voltage to do the work.

It seems part of the trick is to limit the current in the primary, as I suspect Tony is indicating above with the TC comments, as well as trying to limit the current with the chokes in the VIC circuit.

Is there any possibility in getting the circuit to automatically detect primary coil saturation so as to limit the current accordingly?

TS
« Last Edit: May 01, 2015, 04:17:51 am by timeshell »

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##### Re: Restrict Amps with Source Voltage Amplitude
« Reply #1 on: January 04, 2013, 06:23:55 am »
That is very interesting and you maybe right TS. If you look at Stan's Voltage Control Circuit (VCCrkt) and Driver Circuit (DCrkt) along with the VIC Transformer, it is set so that the circuit has a very high impedance to the Primary coil. I have attached an image of the section I'm talking about and I will explain what I mean.

Ok, the TIP120 from the VCCrkt is driving the 2N3055, Darlington Configuration with Emitter Follower. This will increase the impedance by Beta^2. The input impedance of the Darlington configuration is quite high. Switching of the second transistor may be slow, so a resistor is commonly tied between the emitters to increase the speed switching. This will also increase the 220 ohm resistor so that it would look something like this:

Z = Beta * Beta * 220 Ohms

According to the TIP120 datasheet, this transistor has a Beta = min. of 1,000.
The datasheet for the 2N3055, Beta = max. of 70
Z = 1,000 * 70 * 220 = 15.4M ohms

That's a pretty high impedance from the power supply!!! This would allow impedance matching to take place very easily and a more efficient power transfer!
« Last Edit: January 04, 2013, 07:15:20 am by TonyWoodside »

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##### Re: Restrict Amps with Source Voltage Amplitude
« Reply #2 on: January 04, 2013, 14:51:12 pm »
Yes Tony,but as you stated before,and i also saw in real life,if you restrict the amps on the primary side,you also restrict the magnetic field and as a result the output voltage will be verry low

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##### Re: Restrict Amps with Source Voltage Amplitude
« Reply #3 on: January 04, 2013, 15:35:52 pm »
Yes Tony,but as you stated before,and i also saw in real life,if you restrict the amps on the primary side,you also restrict the magnetic field and as a result the output voltage will be verry low

Seems to me that if the coils are current saturated, we may not be getting the proper resonant effect we are looking for.

TS

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##### Re: Restrict Amps with Source Voltage Amplitude
« Reply #4 on: January 04, 2013, 23:54:33 pm »
That's right TS! The way the power supply is configured, it will keep the transformer from becoming saturated.

Here's a simple way of making the Voltage Control for testing purposes.

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##### Re: Restrict Amps with Source Voltage Amplitude
« Reply #5 on: January 05, 2013, 00:09:36 am »
That's right TS! The way the power supply is configured, it will keep the transformer from becoming saturated.

Here's a simple way of making the Voltage Control for testing purposes.

This may be a somewhat redundant question, but you don't have a 2n3055 in your schematics for your VIC.  I presume these attachments with the 2n3055 are to add on top of your VIC circuit.

TS

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##### Re: Restrict Amps with Source Voltage Amplitude
« Reply #6 on: January 05, 2013, 01:15:48 am »
Yea that's right...I never added this to the circuit mostly because some people may have a current limiting power source so that they can control the current to the primary coil.

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##### Re: Restrict Amps with Source Voltage Amplitude
« Reply #7 on: January 05, 2013, 05:37:18 am »
Great,Tonywoodside.

this can replace variac of meyer,solid state variac. in dc current limit by duty cycle but voltage limit by resistor.duty cycle can't limit voltage,this why meyer use variac.IMHO.

thanks
geenee
« Last Edit: January 05, 2013, 12:14:16 pm by geenee »