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wavez
04-25-2008, 11:24 PM
Here are some things that I have learned. I apologize if this is a rehash of old information. I hope this will help others. I also hope others will contribute additional info, since I am not formally educated in EE.

For the uninitiated, BEMF = back electromotive force, and effects all modern electric motors, as well as generators. The BEMF can be eliminated, however. Examples of No-BEMF motors would be the Bedini SSG, and Dr. Lindemann's Attraction Motor design.

Why do we care? This principle applies not just to motors, but to all electrical inductors, such as transformers and electromagnets. Inductors are used in many OU systems, such as the Meyer WFC, Bob Teal motor, Joseph Flynn PPMT motor, Bedini Energizer, etc etc. Chances are that if you are interested in OU systems, you should understand BEMF.

As I have learned from Dr. Lindemann's Electric Motor Secrets, (which I highly recommend) BEMF is an effect which happens entirely within the wire of a motor or generator, and is created due to the nature of direct electrical induction.

As we all know, moving a magnet past a coil creates a current within the coil. What we aren't taught in school is that there is an additional effect; the BEMF (or CEMF). The Back EMF is created when the magnetic field collapses. This works both ways, whether we are using a magnetic field to create electricity, or using electricity to create a magnetic field. Normally we supply additional power to overcome the BEMF effect, since it exits the coil in the opposite direction from which the current flows while the magnetic field is supported. Below is a simple example of how the Bedini SSG captures BEMF and shunts the power to an alternate power storage device, such as a capacitor or a battery. I owe a thank you to Introvertebrate of youtube for his illustration which helped me understand this. I have recreated his illustration here in a gif file (both are animated, click the thumbnails).

http://www.hotlinkfiles.com/thumbs/small/1251936_rxmpk/BEMF1.gif (http://www.hotlinkfiles.com/view/full/1251936_rxmpk)
http://www.hotlinkfiles.com/thumbs/small/1235695_3sbq2/bedini-diagram.gif (http://www.hotlinkfiles.com/view/full/1235695_3sbq2)

You can test this effect quite easily by creating the simple circuit that I show, but minus the transistor. I like to use the AAA battery packs from radio shack because they have built-in on/off switches, and the leads can easily be pressed directly into my breadboard. Before the test, you short out the capacitor (to discharge it) and measure it's voltage. Then place it into the circuit and switch the batteries on and off quickly. Then pull the capacitor and check the voltage, it should have risen. Now do the same experiment, but replace the inductor with a short. You should see a mA increase in your cap, because any power within the circuit while the battery is connected is then going to be gathered in the cap once the battery power source is gone. Keep in mind that the BEMF is a high voltage, low amperage power spike. You could use a step down transformer to raise the amperage and lower the voltage, if you need. The factor you must consider is this: is your capacitor good enough to store the BEMF pulse? I've been told that the cap's ESR rating should be considered, and that electrolytic capacitors can be quite slow, which leads me to suspect that you may not get full potential efficiency if using an electrolytic. A cap bank of mixed types has been suggested.

For the inductor, I was able to use one of the radioshack magnet wire spools which I had not yet unwrapped. I could tell the wire had been wrapped perfectly, so all I had to do was remove the enamel from both ends (using sand paper) and I was good to go. I later added RG45 rods for the iron core, and super glued them in. I don't recommend RG45, btw, because they will retain magnetism after much use.

I then created this next circuit to shunt the BEMF back to the original power source. In the case of the Bedini SSG, the primary battery.

(no animation)
http://www.hotlinkfiles.com/thumbs/small/1251966_ppika/BEMF2-a.gif (http://www.hotlinkfiles.com/view/full/1251966_ppika)

I'm obviously leaving out any mechanism to trigger the transistor. As John has done in the past, you could trigger it with a Hall effect sensor, or replace it with a reed switch. I have found that using the bifilar coil method is actually the easiest to build though. While it seems to me that the circuit shown above should work for some systems, it does not work for a Bedini system (or at least not mine). Instead, I had to create this variant:

http://www.hotlinkfiles.com/thumbs/small/1251965_puo48/BEMF2-b.gif (http://www.hotlinkfiles.com/view/full/1251965_puo48)

So if we include the sensing coil in the diagram, it looks like this:

http://www.hotlinkfiles.com/thumbs/small/1251990_s8bmn/BEMF2-c.gif (http://www.hotlinkfiles.com/view/full/1251990_s8bmn)
(don't forget your neon and 1n4001 on the transistor, I have excluded them here)

I have been able to run my SG rotor-and-coil setup using this circuit and a single battery, so I consider it a success. More testing is needed to conclude if the diodes (which are 1n4007) are fast enough to capture 100% of the possible BEMF power. I consider this a simple no-BEMF motor. I have not yet seen any self-running, OU-type power gains using this circuit. It could be that my coils are simply not good enough. They are exceedingly mediocre. Based on everything I have learned and observed, I would have to say that the OU which John reports would indicate that collecting the BEMF can create more power than was originally induced in the coil, but I personally have yet to see over 100% power recovery.

A simple astable multivibrator could be used to drive the transistor and you would then have a Bedini solid state system. I think this is a little impractical though, since the potential mechanical energy is still there for the taking. Not only that, but it should be possible to use the rotor as a generator, which would load it down, but that also draws less current on the motor, so in theory, it sounds like a good situation over-all.

Additional thoughts and considerations:
If you run a motor with this circuit, then you are constantly taking and replacing small amounts of power from the battery. I have no idea what effect this would have on a battery. It may be desirable to arrange two batteries to be used as a primary bank, so that power is always entering one and exiting another.

Also... use a breadboard, don't use solder! If you blow the transistor, then you're really going to regret having not used one. Not to mention how much easier it is to setup each new experiment...

dodeca
04-26-2008, 05:48 AM
I would like to add two things I notice about the SG.

1. I see a lot of experimenters use aluminum in their wheel. I believe spinning aluminum will repel a magnet.

2. In the standard SG circuit the charging battery looks like a capacitor ( or better said ACTS like one ) ... so at the right speed ( frequency ) does it achieve resonance?

I do believe we can figure out FREE ENERGY. I tend to believe we are trying to tap into existing energy fields ( gravity? ) so ... it's like a solar cell ... but using gravity and not having to loose power when the sun sets.

BTW ... nice write up!

Dodeca

Sephiroth
04-26-2008, 03:41 PM
Nice wirte up though a couple of points/questions...

aren't you combining the terms Back EMF and Flyback voltage?

You are right that in any standard motor the magnets going past the coils are generating Back EMF that cuts down the effective voltage. Though the Flyback Voltage is what occurs when the magnetic field collapses and that is what charges the batteries.

Though can we consider the Bedini SSG as a non-back emf motor? As I understand as long as you have magnets going past your coil you are going to have back emf. A pulsed system can be used to reduce the effect of back emf, though it is still present isn't it?

:D By the way, I made another animation for youtube:
YouTube - Understanding the Bedini Circuit (http://uk.youtube.com/watch?v=yi7cmUpMdX8&watch_response)

theremart
04-26-2008, 05:43 PM
I have noticed that the SSG Bedini appears to have both as well..

Everytime the magnets go by the coil it is putting back EMF into the primary side of the Bedini. I have found this to be true buy replacing the primary battery with a capacitor, and then turning the wheel with another SSG. I found there was like 3-5V on the cap on my setup.

So it seems to me that the battery would have to fight this in order to power the coil. Maybee...... this is what we are fighting in our multi coil setups...


Could a diode block this?

Interesting thoughts...

Peter Lindemann
04-26-2008, 06:21 PM
Nice wirte up though a couple of points/questions...

aren't you combining the terms Back EMF and Flyback voltage?

You are right that in any standard motor the magnets going past the coils are generating Back EMF that cuts down the effective voltage. Though the Flyback Voltage is what occurs when the magnetic field collapses and that is what charges the batteries.

Though can we consider the Bedini SSG as a non-back emf motor? As I understand as long as you have magnets going past your coil you are going to have back emf. A pulsed system can be used to reduce the effect of back emf, though it is still present isn't it?

:D By the way, I made another animation for youtube:
YouTube - Understanding the Bedini Circuit (http://uk.youtube.com/watch?v=yi7cmUpMdX8&watch_response)

Dear Wavez,

First of all, this is an excellent thread to start! Thank you. The understanding of Back EMF and its function in motors, generators and transformers is ONE of the keys to understanding the true behavior of electricity and magnetism.

In my DVD Electric Motor Secrets, I begin this exploration. In the EMS thread, we have explored it a little more. In that thread. I introduced a circuit for recycling the recovered energy of the "inductive collapse" back to the front of the circuit, using an isolated winding and a single diode. In that system, I also isolate the battery with another diode, and capture and store the recovered energy in a capacitor that sits between the battery and the rest of the circuit.

Your introduction of the circuit that can recover the "inductive collapse" from a single coil and return it to the front of the circuit, using two extra diodes is EXCELLENT!!!!!:thumbsup: The trade-offs between using either of these two methods involves the voltage drops in the diodes and the inductive losses of the second coil. That both methods work is now proved by your experiments. The question is, how to set up the front of the circuit to best take advantage of this recovered energy.

I think you will find, that although your one battery system SEEMS to be running OK for now, I believe you will see (as all others have before) that the battery will not tolerate being charged and discharged simultaneously for very long. This was the purpose of placing a capacitor in-between the circuit and the battery, and protecting the battery from the "charge-back" impulses. This allows you to run the motor on "the losses in the system" consisting of the difference between the energy used and the energy recovered. If the electrical "losses" in the system can be kept below 25%, the probability of producing a COP>1 system is raised considerably.

This energy management method, DOES NOT constitute a "no back EMF" motor design, from a technical point of view. It DOES represent a method to recover energy in a pulsed motor design that is usually wasted, and reuse it IMMEDIATELY, instead of storing it in a battery for use LATER. Bedini's SSG designs manage this recovered energy VERY WELL by storing it in a second battery for later use.

"Back EMF" as I define it in my DVD is the "reverse generated voltage" in an electric motor run on direct induction topologies. This phenomena REMAINS INSIDE the machine and cannot be brought out and recovered. It CAN BE engineered around, using passive iron rotors and switched reluctance methods. "Counter EMF" as I define it in my DVD is the normal Lenz Law behavior that causes the phenomena of "current rise-times" and "current decay times" when an inductor is turned ON and OFF. This phenomena CANNOT BE engineered around, and appears under ALL circumstances when electromagnetic fields are produced from electric current traveling in a wire.

It is very important that experimenters know the difference between these two processes and do not confuse them.

Thanks again for starting this thread!!!

Peter

Sephiroth
04-26-2008, 06:25 PM
I have noticed that the SSG Bedini appears to have both as well..

Everytime the magnets go by the coil it is putting back EMF into the primary side of the Bedini. I have found this to be true buy replacing the primary battery with a capacitor, and then turning the wheel with another SSG. I found there was like 3-5V on the cap on my setup.

So it seems to me that the battery would have to fight this in order to power the coil. Maybee...... this is what we are fighting in our multi coil setups...


Could a diode block this?

Interesting thoughts...

I'm not sure if adding more coils increases the problem since they are in parrelel so the back-emf/input-voltage ratio won't increase.

Though you gave me a thought... back emf won't increase as you add more coils in parrelel, though it will increase if you add more turns to each coil!

So if you use a 5-filar slave coil of 200 turns, would you have 80% less back emf then a single filar 1000 turn coil?

wavez
04-26-2008, 06:59 PM
Let me first say that I'm very excited to have both Sephiroth and Dr. Lindemann contributing to this thread. I'm a big fan of your work doctor, and I highly value all the many years of experience that you share with us.

I'm really glad that I started this thread, because I see that I have more yet to learn! This is very important for the work that I have been doing.

Gotta run at the moment, but I shall return :)


Once I am able to study and understand these things that you all have mentioned, then I can consolidate that information and add it back to the original post so that we will have a collection of correct information all at the beginning of this thread.

theremart
04-26-2008, 07:50 PM
I'm not sure if adding more coils increases the problem since they are in parrelel so the back-emf/input-voltage ratio won't increase.

Though you gave me a thought... back emf won't increase as you add more coils in parrelel, though it will increase if you add more turns to each coil!

So if you use a 5-filar slave coil of 200 turns, would you have 80% less back emf then a single filar 1000 turn coil?


My test for that is to to put a capacitor in place of the primary battery and power the wheel with another ssg. The results should prove to be interesting.

I will have to do that with my 3 transistor SSG setup and compare it to my single coil SSG.

So many options to play with ...

gmeat
04-26-2008, 08:42 PM
"Counter EMF" as I define it in my DVD is the normal Lenz Law behavior that causes the phenomena of "current rise-times" and "current decay times" when an inductor is turned ON and OFF. This phenomena CANNOT BE engineered around, and appears under ALL circumstances when electromagnetic fields are produced from electric current traveling in a wire.

It is very important that experimenters know the difference between these two processes and do not confuse them.

Thanks again for starting this thread!!!

Peter[/quote]



Hi Peter,

Just a quick thought here on "Current Rise Time and Current Decay Time" .What if half the INDUCTOR coil is wound clockwise and half is wound counterwise,How do you suppose this would affect the rise and fall time?, Or am I just asking another :beamup: question.Anyways I just thought I'd throw my 2 cents in for what its worth.Try not to Flog me to much for this question:peaceflag: .thx


-Gary

Peter Lindemann
04-27-2008, 12:44 AM
"Counter EMF" as I define it in my DVD is the normal Lenz Law behavior that causes the phenomena of "current rise-times" and "current decay times" when an inductor is turned ON and OFF. This phenomena CANNOT BE engineered around, and appears under ALL circumstances when electromagnetic fields are produced from electric current traveling in a wire.

It is very important that experimenters know the difference between these two processes and do not confuse them.

Thanks again for starting this thread!!!

Peter



Hi Peter,

Just a quick thought here on "Current Rise Time and Current Decay Time" .What if half the INDUCTOR coil is wound clockwise and half is wound counterwise,How do you suppose this would affect the rise and fall time?, Or am I just asking another :beamup: question.Anyways I just thought I'd throw my 2 cents in for what its worth.Try not to Flog me to much for this question:peaceflag: .thx


-Gary[/QUOTE]

Dear Gary,

How could I ever get upset at a guy who chooses to present himself as a drunken cat splayed-out in a corner with beer bottles everywhere? I love you, man!! Here's one on me :cheers:

Your question is a good question, and the answer is not so easy. In an air-core situation, the current rise times in each coil are extremely fast, and the two magnetic fields simply co-exist is the same space at the same time, creating what is referred to as a TENSOR FIELD. It actually functions as a compression wave in the Ether. These types of coils can be used effectively in Radionic devices, and the like. A fair amount of work has been done on this. Sometimes the resultant is referred to as a "motional electric field" and some researchers have demonstrated artificial gravity effects with some set-ups.

If the coils have a common core material, like iron, the bucking fields both try to align the magnetic domains in the iron. Since the domains cannot align in both directions simultaneously, the rise time of the fields and the currents is dramatically delayed.

So, the answer to your question is...... it depends on a lot of other factors, too numerous to mention.:wall:

Keep thinkin', but better yet, run some experiments, and see for yourself.

Peter