Shorting the gen coil with PWM? .. and other things.

[alvarohn]

I have been reading for a while, the threads in some websites about shorting the gen coil.

And I am starting to do tests with it.

All the videos and schematics I have seen are shorting the gen coil at the peak of the wave. This sounds good

… but I have not seen anyone shorting the gen coil all the time, multiple times, not only when the sine wave is on the peek.
So first I would like to know if you people think that is logical for you, as it is for me.
Because… shorting at the peak would give the bigger spike, but we are wasting all the others possible spikes.

So regarding that, and since I don’t have a great electrical background, I was wondering if a self-oscillating circuit could be used to short a generator coil (PWM style) ??? . For example, use the oscillation of a joule thief to short a gen coil (placed in a rotor with magnets of course).
---
Another question I would like to ask: Can I dump a capacitor into a coil? And expect the coil to be able to push an incoming magnet? And also get a radiant spike?
My basic idea is to put gen coils, been shorted all the time, and storing the radiant output into a capacitor, then with the right timing discharge that cap into another coil to help the rotation of the device, and also gather the radiant spike of that cap dump into the coil. Is logical?

Thank you

Best

Alvaro Hernandorena

[Matthew Jones]

All the videos and schematics I have seen are shorting the gen coil at the peak of the wave. This sounds good

… but I have not seen anyone shorting the gen coil all the time, multiple times, not only when the sine wave is on the peek.
So first I would like to know if you people think that is logical for you, as it is for me.
Because… shorting at the peak would give the bigger spike, but we are wasting all the others possible spikes.

You have to have power in the coil for the spike to show up. And shorting the spikes consume some of the energy in the coil. So shorting just as it starts to charge doesn't make sense. Same as its discharging.

So regarding that, and since I don't have a great electrical background, I was wondering if a self-oscillating circuit could be used to short a generator coil (PWM style) ??? . For example, use the oscillation of a joule thief to short a gen coil (placed in a rotor with magnets of course).

You have to go slow. It takes time for the spikes to show up so the oscillators you chose needs to be flexible for adjustment and slow enough to allow it to happen. Think MICRO CONTROLLER. Also you need to boost the current to voltage so you can eliminate a lot of steps by calculating the frequency and the output with the coil you intend to use. Boost Calculator. Mind you the calculations put out by this calculator apply to different circuits but aren't always spot on even in the outlined circuit. You'll have to know how much power is in the coil prior to setting up the shorting circuit.

Another question I would like to ask: Can I dump a capacitor into a coil? And expect the coil to be able to push an incoming magnet? And also get a radiant spike?

Yes. To size the capacitor correctly you will have to know how much power is in the coil at saturation plus loss. Then convert to Joules and calculate the size of the cap needed. Solenoid calculator. Electronic Assistant 2000
Both of these tools will help.

My basic idea is to put gen coils, been shorted all the time, and storing the radiant output into a capacitor, then with the right timing discharge that cap into another coil to help the rotation of the device, and also gather the radiant spike of that cap dump into the coil. Is logical?

Yep!!! It sure is but the fact that you do not know its possibles speaks to the fact you have some learning to do. This circuit will be high in switching and will require a bit of know how. You wanna start small and work up a piece at time till you can build it. Or find some stuff to replicate. Try to search Konzen and look through his circuits.

Cheers and good luck.
Ask if you need help.

Matt

[alvarohn]

Thank you Matthew for your reply,

about this:

"You have to have power in the coil for the spike to show up. And shorting the spikes consume some of the energy in the coil. So shorting just as it starts to charge doesn't make sense. Same as its discharging."

please look at the vid https://www.youtube.com/watch?v=Lxh3XnU8lko at the 2:09, he shows an scope shot of the coil been shorted at the peeks.

In that video is shown that the voltage of the coil does not go down after the shorting, the wave goes to the top... is shorted.. produces the spike... and continues on the top. This means that the shorting don't make the coil start from 0, or at least the coil regenerates instantly.

best,

[Matthew Jones]

or at least the coil regenerates instantly.

You have to have power in the coil before the spikes of voltage will show up. The coil has to be near saturation for the biggest spikes. Then when you short it, it boosts the current in the coil to high voltage. The high voltage does not leave the coil quickly. So you reconnect to the system then the high voltage leaves. The coil is still saturated and you do it again.
But power has to be generated or put into the coil for the effect to happen.

So highest point of saturation is going to give you the largest most effective spike while leaving power (In the form of a magnetic field) in the coil. If the coil is saturated the coil is charged.

So look at the curve of the power it also represents the curve of the saturation. If you have 1 volt worth of power in the coil and you short it you'll get no spike and you'll just lose the power from saturation and have to start over. If the coil is fully saturated then you don't but your current drops. Voltage will remain the same. But you overall power is reduced.

Amps x Volts = watts...

Follow me?

Matt

[alvarohn]

Yes I understand what you say. But I would have to test it to be sure.

Can you recommend me the simplest way to make a adjustable shorting circuit? Is the 555 the simplest option?

Best

Alvaro Hernandorena

[Matthew Jones]

Get a micro controller with an ADC to watch the voltage and learn to drive a higher voltage transistor between the 2 legs of gen coil with an H11d1. To me thats the simplest but you scour this and other forums, you might find an analog setup.

You can by a little micro controller from Parallax called a Prop Stick and they have cheaper one also on a board just look through the sight. You can add an ADC to it.

It will be your best friend soon.

Matt

[alvarohn]

need help again

Hello, well I made some progress with my little project,

I have the frame + rotor + magnets

the other night I made the first coil (which is the power coil) I made it bifilar but with thin wires, since the device is small (for testing).

I intended to use the SSG circuit to drive the rotor and then add the gen coils.

it would be a low voltage SSG circuit (1,2 volts).

I made the circuit using a 2n2222 transistor, but I couldn't get it to trigger, tried everything, the circuit is correct, but with 2n2222 and 1,2 volts primary, but it wouldn't trigger...

Lastnight I removed the ssg circuit and used a reed to trigger the power winding and it works, but I have the feeling that the reed eats up the primary battery (probably because it can't be tuned like a transistor using base resistance).

So can somebody helpme up? is possible to make this little ssg trigger with that tranny and 1,2 v?

I also used 5 volts (knowing that it would burn the 2n2222) but it wouldn't trigger either.

I attach pictures to show the sizes of rotor and coil. (for reference the rotor thickness is 2 cm (0.78 inche)).



best

Alvaro Hernandorena

[Matthew Jones]

2n2222 is a 30v to 50v transistor, so 5v shouldn't hurt it.

Sounds like either the trigger winding is connected backwards, 1,2v is not enough for the power winding to make a field (IE Low ohm coil) , or the transistor is already burnt.

That the only advice I can give you.

Matt

[alvarohn]

2n2222 is a 30v to 50v transistor, so 5v shouldn't hurt it.

Sounds like either the trigger winding is connected backwards, 1,2v is not enough for the power winding to make a field (IE Low ohm coil) , or the transistor is already burnt.

That the only advice I can give you.

Matt

Hi Matt tnx you have always helped me.

I tried changing arround the trigger winding and it didn't work either. Now I have spining with a reed switch.

So you think it should trigger no matter the low voltage? I am going to try again. In the diode emitter to base I have a 1n4007 ... I only have those right now, you think that big diode is the problem?

Best

Alvaro

[shylo]

your coil

Hi Al, In that pic of your coil, is it coreless with 2 magnets set 90 degrees apart?
Shorting a coil gives a spike, but if it has a steel core , the drag of the steel will out weight the spike.
Just what I've seen in my tests, my shorting is mechanical and random but can collect more than no shorting.
Great thread looking forward to more.
Thanks artv

[Matthew Jones]

Hi Matt tnx you have always helped me.

I tried changing arround the trigger winding and it didn't work either. Now I have spining with a reed switch.

So you think it should trigger no matter the low voltage? I am going to try again. In the diode emitter to base I have a 1n4007 ... I only have those right now, you think that big diode is the problem?

Best

Alvaro

No the diode shouldn't be a problem but at 1 volt you may not be getting anything out of it. They do have lossless diodes now "No recovery" look them up on Digikey.
You got it wired right on the transistor. 123 CBE Collector Base Emitter.

Its kinda a hard thing to diagnose on the remote. It may be firing and the combination of everything you got going doesn't give you enough power to rotate the wheel.

The other thing to check is the voltage on the base. Make sure its good with your data sheet.

Matt

[alvarohn]

Hi Al, In that pic of your coil, is it coreless with 2 magnets set 90 degrees apart?
Shorting a coil gives a spike, but if it has a steel core , the drag of the steel will out weight the spike.
Just what I've seen in my tests, my shorting is mechanical and random but can collect more than no shorting.
Great thread looking forward to more.
Thanks artv

right now the only coil with core is the central one that is not in generation mode, is just the motor coil, it uses SSG circuit.

I haven't tried iron core vs air core in my generator coils yet.

best,

Alvaro

[alvarohn]

No the diode shouldn't be a problem but at 1 volt you may not be getting anything out of it. They do have lossless diodes now "No recovery" look them up on Digikey.
You got it wired right on the transistor. 123 CBE Collector Base Emitter.

Its kinda a hard thing to diagnose on the remote. It may be firing and the combination of everything you got going doesn't give you enough power to rotate the wheel.

The other thing to check is the voltage on the base. Make sure its good with your data sheet.

Matt

Matt thank you, yesterday I made it work, the problem was the coil itself, the power winding was too thick.

The power winding been too thick didn't left much room for lots of turns, so the trigger winding wasn't producing enough energy to trigger.

I made another coil with the 2 windings same thickness (both power and trigger winding have now 12 ohms), and it triggers now!!!! and the 2n2222 doesn't get hot using 5v input.

So problem solved. I have the ssg working now.

Yesterday I made basic tests with 1 of the gen coils, with no shorting, just gen coil (air core) through bridge rectifier to cap, gives 2.5 volts. When shorted (for now using just 1 reed switch) I can get up to 70 volts.

I attach some pics



best,

Alvaro

[Matthew Jones]

Matt thank you, yesterday I made it work, the problem was the coil itself, the power winding was too thick.

The power winding been too thick didn't left much room for lots of turns, so the trigger winding wasn't producing enough energy to trigger.

I made another coil with the 2 windings same thickness (both power and trigger winding have now 12 ohms), and it triggers now!!!! and the 2n2222 doesn't get hot using 5v input.

So problem solved. I have the ssg working now.

Yesterday I made basic tests with 1 of the gen coils, with no shorting, just gen coil (air core) through bridge rectifier to cap, gives 2.5 volts. When shorted (for now using just 1 reed switch) I can get up to 70 volts.

I attach some pics



best,

Alvaro

Its not always possible right away but get scope and learn how to use it. Then you get true test of what kind of power your dealing with.

I am happy for ya.
Matt

[shylo]

rotor

Hi Al, Do you have a still shot of that rotor?
In motion it's hard tp tell.
I'm assuming they're magnets , the black blurs ?
artv