Method to Dump cap voltage to Battery

[nvisser]

We all know the 555 timer circuit that can be adjusted to pulse a cap with intervals to dump the charged cap from the reactive power of the ssg to the charge battery
Does anybody know how to dump a cap that is charging from a ssg to a battery when the cap voltage reach say 24v, with a scr by using only resistors , caps and a zener to sense the voltage and trigger the scr? As soon as the cap is discharged which is very quickly the scr should switch off again

[baroutologos]

hello vissie,

I have done what you say, by using a potensiometer, resistors, zener diode, optocoupler, small transistor, SCR. The problem is, if the SSG or anything supply more current than the SCR or TRIAC requires to switch off, then it does not switch off.

Ideally, you must devise a mechanism that when dumping occurs the SSG is not powered.

Baroutologos

[Inquorate]

2 zener diodes

Use 2 zener diodes, one to trigger the gate at a particular voltage, another to stop the anode from conducting at another voltage.

Use potentiometers as voltage dividers to raise the actual voltage trigger / stop levels to above the zener breakdown level.

[nvisser]

Is there any way you can post a schematic? A scanned hand drawing?
Your circuit sounds promising

I found this somewhere and tried it using a triac, But could not get it to trigger at all. The picture quality is not very good

[Inquorate]

Schematic

Cap pulse circuit - Vox

Click on the images for the full description.

Happy soldering

[Bodkins]

great stuff ben. good question nvisser

[Inquorate]

Open source

great stuff ben. good question nvisser

Gotta share the love

[nvisser]

Thank you. Is the 15v zener high wattage to handle the surge?
How will we use potentiometers as voltage dividers to raise the actual voltage trigger / stop levels to above the zener breakdown level.

[Inquorate]

Untried

I haven't used the potentiometer idea, I worked out the rest thru trial and error; it never works the way I initially picture the circuit. It may be as simple as adding a resistor in series with the zener diode to the gate, similar to how an led must be protected from a 9v battery. The two in series essentially become a voltage divider (any two components with resistance will do that) so the zener diode will see a fraction of the voltage behind the resistor.

The 15v zener can handle the surge if the cap is of small capacity, but adding more in parallel would increase ability to handle the surge if that was a problem.

I would try it without the anode zener first unless circuit load Impedence is required to be fairly constant.

As soon as the voltage on the cap = the voltage on the battery, the scr will switch off, and the gate will need to be re triggered for current to resume flow.

23/10/2009 - Vox

Potentiometer as a voltage divider : DC CIRCUITS

Pls share your findings, and maybe someone else can chime in if they know more.

Love and light

[nvisser]

I ordered some scr`s today. The previous test was done the same way you suggested without the 15v zener, but I used a triac. What happened was like Baroutologos said earlier. The scr would not switch off as the radiant or reactive power from the coil charged the cap up very quickly and the current keeps on flowing. It looks like with radiant energy the voltage before the scr never realy goes as low as the battery voltage, so the scr does not want to switch off.
I have done this dumping circuit before by using the timer, opto and two transistors instead of the scr . I think that will maybe work better , as a transistor does not stay on after the biasing is removed. I will try that to and report back.
I ask the same question on a electronic forum. Of cause they dont know about voodoo energy, but I got a circuit from them. It also did not work but again I used with what I had. A triac. See: SCR switching - Electronic Circuits Projects Diagrams Free See post 11

Another circuit is the neon peak detector as mentioned before, But it will only trigger at 70V . Not to good for a 12v battery I heard?. Maybe the neon can be substituted with a 24v zener. Here is a circuit . We are only interested in part of the circuit although the complete diode plug circuit are quite interesting. See:Rotoverter: RV Resonance Recovery Test Circuit - Half Diode Plug Across Run Cap | MERLib.org

Here is another one where they use a diac DB3 that switch at 28v.
Image:TV-v1b.png - PESWiki

Still I am looking for a very simle circuit like the one Iquorate suggested

[baroutologos]

Perhaps i have been tagged here as non believer and bad guy, but my word is never bull. I double check what i say for sure.

....
In our case, or your case, if the cap is very small (few uFs) it wil never allow the triac or scr to shut down. there are certain ways to force an SCr to switch off but those are turning the circuit rather complicated.

Zener diodes as Inoquorate suggests are a clever idea indeed. But again you can run upon some difficulties, again, especially for small caps that the SSG will keep them always high voltage value. Whereas the larger caps will create an huge pulse towards batteries and diodes will find it difficult to handle those, not to mention losses.
The best way of course is mechanical dump. Period.

....
In solid state components however, the best way i have found is making a double switch. i.e. during dump, the SSG goes off. Like FEG (in single batteries setup). when the battery is pulsed, the motor is off. As simple as it gets for trustworthy results.


Baroutologos

[Inquorate]

Simple mechanical cap dump using relay

Capacitor dump using relay - Vox

This is one way to do what baratoulogos said.

[BobBrown]

Bah ! just when I though I had something to make

Hehe, What if, instead of using a 555 timer to time the coil pulse and, Capacitor dump. I instead tolk a 741ic and used it as a comparator, using the sample side ( pin 2 ) to measure the voltage at the capacitor. When the voltage got to EXX amount, the 741 would go high, starting the Capacitor dump. At the same time signaling the 555 timer to stop pulsing the coil.


Andrew T, from http://www.energeticforum.com/renewa...ate-trial.html
Schematic at post 11

Hmm,
Would or should eliminate IC1, the 555 timer I'm using to separate the Capapacitor dump from the coil pulsing timing.

Ah dear, have I done a bad by cross posting?

[nvisser]

As promised. Here is the working diagram
See http://www.energeticforum.com/renewa...g-motor-8.html
Around post 158

[sucahyo]

Nice circuit . That is much better than timer.