Bedini SG

[Sephiroth]

He says there are 80 power windings... so 80 power windings on 10 coils is 8 windings per coil in parallel, which is reasonable... though it looks like it will be low impedance.

For the rotor to manage "tens of thousands" of rpms, then the inductance of the coils must be very low.

[Mark]

I have a hard time believing a rotor that big could go even 10,000 rpm let alone 10's of thousands.

[nvisser]

[QUOTE=Sephiroth;67979]He says there are 80 power windings... so 80 power windings on 10 coils is 8 windings per coil in parallel, which is reasonable... though it looks like it will be low impedance.

Ok ,that is more realistic, I had it completely wrong
That means 8 transistors/coil?

[Shamus]

@nvisser: Yes, if they're following the usual multistrand/multicoil setup, it will be eight transistors per coil. Though on the BM3 group Rick mentioned that they had improved upon John's original design, so that might not be valid.

@Mark: It may be possible, especially if they run it at higher voltages. In my (admittedly limited) experience with 24V, I've seen energizers that normally run around 1,500 RPM shoot up to almost 4,000 RPM (it's a 6.5" rotor). So maybe 10,000 RPM may not be all that far fetched after all, especially if they're pushing 100V or so.

EDIT: It seems that 4K measurement was in error by a factor of 2. Still, from 1,500 RPM to 2,000 RPM is nothing to sneeze at.

[baroutologos]

Good techs and figures.
The issue? Is it OU? If not... what is it? Big Battery desulfator?

Regards,
Baroutologos

[Mark]

Hi Shamus

Ive had my window motor running at 5000 rpm on only 12v but it was only a 5 inch rotor. The 10 coiler has a 17 inch rotor, thats huge! I would want to see some numbers on that before a lay down $3500 to $4500 for one.

[nvisser]

I noticed that Rick do answer some question here
Yahoo! Groups

[dambit]

Very glad to see such a large charger for sale.

Clever way to sell them too. As a kit no one would take much notice. (The energy people that is.)

Cheers,

Steve

[morpher44]

Bedini SSG thoughts

I had a thought regarding the SSG to pass along in case anyone wants to pursue this.

The bifilar coil in the SSG will have a certain inductance, depending on geometry, number of turns, ferro material, etc.

The motor will spin at a certain RPM, creating a certain oscillation.

XL = 2 * PI * f * L

where f is your oscillation frequency (motor spin frequency),
and L is your coil inductance.

You will notice in this equation that as the spin frequency
increases, so does XL ... which will have the effect of
a larger reactance ... which will impede more current flow, slowing
down the motor. So there is a sweet spot whereby
a balance is struck with XL, the current flow
and the motor speed (all dictated by your coil).

If you have an absolutely huge L, your motor may not even turn ...
or it will turn slowly. Too small a value of L might allow enormous
current flow from your battery to motor, creating a very fast
frequency yes, but your poor battery is draining too fast.

If someone where to PLOT these relationships out
in terms of the inductance relative to RPM relative to
other metrics such as current from drive battery, etc.,
these non-linear curves could be analyzed using
non-linear curve fitting algorithms to help find
the optimum value for L for your coil.

W/o this careful approach, your coil winding is a crap shoot.
Some will be impressed how fast their motor turns but
unimpressed in how fast the battery is charged.
Yes there is a POT controlling current to the transistor,
but the coil is a more dominate PLAYER in the
power equations.

Perhaps the coil should have a variable inductance ...
a ferro material that can be moved in and out of the form
to find the sweet-spot.

[Sephiroth]

I had a thought regarding the SSG to pass along in case anyone wants to pursue this.

The bifilar coil in the SSG will have a certain inductance, depending on geometry, number of turns, ferro material, etc.

The motor will spin at a certain RPM, creating a certain oscillation.

XL = 2 * PI * f * L

where f is your oscillation frequency (motor spin frequency),
and L is your coil inductance.

You will notice in this equation that as the spin frequency
increases, so does XL ... which will have the effect of
a larger reactance ... which will impede more current flow, slowing
down the motor. So there is a sweet spot whereby
a balance is struck with XL, the current flow
and the motor speed (all dictated by your coil).

If you have an absolutely huge L, your motor may not even turn ...
or it will turn slowly. Too small a value of L might allow enormous
current flow from your battery to motor, creating a very fast
frequency yes, but your poor battery is draining too fast.

If someone where to PLOT these relationships out
in terms of the inductance relative to RPM relative to
other metrics such as current from drive battery, etc.,
these non-linear curves could be analyzed using
non-linear curve fitting algorithms to help find
the optimum value for L for your coil.

W/o this careful approach, your coil winding is a crap shoot.
Some will be impressed how fast their motor turns but
unimpressed in how fast the battery is charged.
Yes there is a POT controlling current to the transistor,
but the coil is a more dominate PLAYER in the
power equations.

Perhaps the coil should have a variable inductance ...
a ferro material that can be moved in and out of the form
to find the sweet-spot.

Here is something that visually represents what you are saying... have a look at the scope shots in this video from about 1:20mins onwards...

YouTube - MG-1 : Pulse Motor Generator (SSG)

you can see the pulse train for each magnet pass, and where the back emf is greatest (around the centre of the train) the pulse width is longest because of the way the back emf is holding back the current and making it take longer for the magnetic field to reach saturation.

I agree that the inductance of your coil needs to be well chosen if you have a particular purpose in mind... Though inductance isn't the only factor, since although these coils are fairly low inductance, I'm making use of their geometry to hold back the current long enough for single pulses.

[nvisser]

Does someone know from which thread the following diagram comes from. I downloaded it somewhere late one night. I labelled it "bedini feedback to chip"
I need to know why the 1 uF cap is switched in series with the trigger coil and the wattage of the 12v lamp?
I was under the impression that at least the half bipolar switch must be used to send the "reactive power" back to the battery the instant when both polarities are shut off from the coil as we all know that you cannot charge the battery while it is supplying the load.?
They feed the higher voltage that is generated by the extra generator coil and cap straight back to the drive battery. No pulsing
I am sure this can be done with the correct timing and pulsing , but this drawing does not look right to me and I cannot believe that it comes from bedini. Maybe bedini explained it to somebody and that is the way he drew it?
Any feedback on this please

[uusedman]

Hi Guys-

It is happening again. Whenever I start collecting the BEMF from the collector to a charge batter, the AMP Draw increases?????????? I know it supposed to decrease. I built a new circuit last night and still the Amp Draw increase upon charging the secondary batter. The amount of increase of AMP Draw is about 20%.

The only answer to this problem I can come to is Lenz Law is coming into effect. Can it be that my trigger wire is to long and is generating much more voltage than needed to activating the Base?

[nvisser]

Can anyone tells me what A grain-of-wheat bulb is and what wattage it is

[blackchisel97]

grain of wheat bulb

Hi nvisser,




Vtech

[nvisser]

Thank you. Looks like the little lamps they used in older car radios
60ma tells me what I need