Lockridge Device - Peter Lindemann

[Fuel40]

Back EMF...

Mark, and everyone else,

My goal is to help everyone here, who wants to, learn how to build a self-running system. That said, I do not have time to get involved with "the build" as you put it, because I am too busy working for a living.

What I would like to do is help you all understand what it will take to develop a working design. There are a lot of details that have not been worked out yet, and there is no reason to believe that "the group" here understands the science of what I presented in my lecture.

So we can all get going on the SAME PAGE, I would like everyone who wants to participate in this thread to write down on a piece of paper what your understanding and definition of BACK EMF is.

DO NOT POST YOUR ANSWER. Just write it down as best you can. I told the answer in the lecture, but I don't want early "posters" to influence others, for better or for worse. Then on Sunday night, everyone can post their answer without looking at anyone else's answer. That should give me a pretty clear idea of how people are thinking about this and what they have learned from my lecture so far.

I will figure out how to proceed after this.

Peter

Good evening Peter-

Thank you, for your patience and dedication to educating us in regards to this technoloy. The following is my understanding of back EMF.

When a permanent magnet DC motor’s output shaft is mechanically rotated it spins the coil wound armature and generates voltage. Thus, if current is applied to a permanent magnet DC motor, the spinning armature generates voltage against the input current. Back EMF is the reverse direction generated voltage in a permanent magnet DC motor.

As well, effective armature current is determined by the applied input voltage minus the back EMF. Back EMF destroys the input energy of permanent magnet DC motors.

Finally, it is not possible to eliminate back EMF in commercially available permanent magnet DC motor architecture.

Regards,

Adam

[radiant1]

I totally understand it now

Peter
Mike and I watched both dvds last night stopping very often to discuss them.
I now totally under stand what BEMF is, where and why motors run best, where and why generators run best, why motor eficiancies given by manufactures are bogus, and how to run a motor in such a way as to increase torque and power both as the speed goes up.

Mike and I are going to make a Bob Teal type solenoid motor and have it run a toroid coil generator that has no lenz effect or drag under load. Should be a very efficiant combo.

I will answer the question more fully on Sunday.
Alan

[Peter Lindemann]

My Goals for this Thread

Mark, and everyone else,

My goal is to help everyone here, who wants to, learn how to build a self-running system. That said, I do not have time to get involved with "the build" as you put it, because I am too busy working for a living.

What I would like to do is help you all understand what it will take to develop a working design. There are a lot of details that have not been worked out yet, and there is no reason to believe that "the group" here understands the science of what I presented in my lecture.

So we can all get going on the SAME PAGE, I would like everyone who wants to participate in this thread to write down on a piece of paper what your understanding and definition of BACK EMF is.

DO NOT POST YOUR ANSWER. Just write it down as best you can. I told the answer in the lecture, but I don't want early "posters" to influence others, for better or for worse. Then on Sunday night, everyone can post their answer without looking at anyone else's answer. That should give me a pretty clear idea of how people are thinking about this and what they have learned from my lecture so far.

I will figure out how to proceed after this.

Peter

[Mark]

Hey Goreggie

I was playing with my starter motor a little and it currently has quite a bit of resistance and doesn't free wheel very well and seems to draw a lot of current, I havent checked the free wheel current. I hope the new end caps with bearings will really free it up. I don't think these starter motors are very efficient in their stock configuration. I'm wondering if we'll need to rewind the stators with more turns of smaller wire. Does your motor free wheel fairly well?

I also charged a 250uf 250 volt cap up to 210 volts and discharged it into the motor and it didn't turn at all Hopefully with things freed up and the motor turning with a flywheel things will be different.

Hey Peter have you done any testing yet with the motor or generator? And do you have a time frame in mind as to when you will start to get involved with the build?

Mark

[goreggie]

Hi Goreggie

I purchased the starter today and was wondering what you would charge me for the end plates with the bearing installed. You can private message me or post here.

Thanks Mark

Hi Mark, should not be a problem getting you the end bell, I will check with Carl who cut it, today he was off tommorrow I'm off so by Monday I can reply OK I can tell you this the bearings were $2.00
Right Now I'm setting up two ways to control the firing of the motor, one electronic, the other with brushes Reggie:

[Mark]

Wayne I'm setting up the electronic's right now and if it works I will put the end bells up on the forum at a low cost OK Reggie

Hi Goreggie

I purchased the starter today and was wondering what you would charge me for the end plates with the bearing installed. You can private message me or post here.

Thanks Mark

[Mark]

Goreggie

You have made great progress! Thanks for the info. I have played with the SCR discharge set ups with my solid state Bedini's. Hopefully you have better luck with them than me. I could get them to work great in some set ups but in others they would not shut off. I have only made 1 commutator before and it wasn't precision made. Good luck and I wish I could be there to help.

Mark

[cwaugs]

Wayne I'm setting up the electronic's right now and if it works I will put the end bells up on the forum at a low cost OK Reggie

Sweet, that'd be cool. W

[goreggie]

I just finished watching both videos and have located both the starter and the motor that Peter recomended.

Goreggie, I was wondering if you did an RPM test on the starter. I see that you mounted a larger pulley on it to generate a higher speed on the generator/motor. If so what was the free wheel speed? And have you run the starter to see what kind of speed it has while driving the generator in your current configuation? Also what size are your pulleys?

Looking forward to hearing more on your build. Good luck and I am interested in purchasing you end plates.

Thanks, Mark

Hi Mark, yes we ran a rpm test, the generator has a 1" wheel pulley the motor is 8" wheel pulley with mass. The test did run at 2995 RPMs giving us 261 volts out from the generator but its to early to know if this is correct Right now working on the commutator ...
It may be possible to use a SCR after all. The key is that once an SCR is triggered, it will continue to conduct until the current falls below a specific value. SCRs have sometimes been used in camera flash units to do just what is described: discharge a capacitor through a load.
The "commutator" serves to apply power to the motor at the right time, so that the magnetic fields are the correct polarity at the correct time.
In this case, when the motor is in the correct position the SCR (or other circuit) will fire and apply current to the motor windings. Once the capacitor is fully discharged, the SCR will turn off. If we use another driver, then the control circuit will determine when to turn off the current.
Note everything that happens on this end will be posted
God Bless All

[Mark]

I just finished watching both videos and have located both the starter and the motor that Peter recomended.

Goreggie, I was wondering if you did an RPM test on the starter. I see that you mounted a larger pulley on it to generate a higher speed on the generator/motor. If so what was the free wheel speed? And have you run the starter to see what kind of speed it has while driving the generator in your current configuation? Also what size are your pulleys?

Looking forward to hearing more on your build. Good luck and I am interested in purchasing you end plates.

Thanks, Mark

[dragon]

I believe the current from the capacitor would be I = 2PI*F*C*V so in the DVD example the current discharge would be...

6.28 * 50hz * ( 208uf/1000000 ) * 240 volts = 15.67 amps

On the other hand, the formula for discharging a cap into an inductor would indicate a much higher possibility: V * ( C / L )^.5 or

240 * ( 208uf / 250 uh) ^.5 = 218.9 amps

I'm not sure which is correct in this case....

I plan to make a comutator for testing purposes
________
Zoloft Settlement Information

[radiant1]

re:duty cycle

I was told the "duty cycle" or "on time" will be between 1 and 10 percent.
Alan

[goreggie]

Lockridge Device

Hi Now on to the electronics, First, a quick item to help you if you talk to other engineer types. A "SCR" (Silicon Controlled Rectifier) and it's cousin the TRIAC cannot easily be used to control DC. (see "http://en.wikipedia.org/wiki/TRIAC" and "http://en.wikipedia.org/wiki/Silicon-controlled_rectifier")
Once they are "triggered" they will stay on until the current goes below the threshold for a period of time. This happens 120 times per second with standard AC but does not at all with DC.

To pulse DC, you would use a transistor of some type. A "MOSFET" is a good choice for some applications.

The questions are as follows:

1) What is the maximum current that would be drawn through the transistor?
2) What is the maximum voltage that would be switched?
3) What is the maximum and minimum pulse width?
4) What is the maximum "duty-cycle"? (Percentage of time that it will be switched on?)

Thanks,

[goreggie]

Having sealed ball bearings on both end housings already is why I like the Delco starter/ generator from 60's and 70's lawn mowers. same size physically but the field windings are split. Correct me if I'm wrong but I suppose it is to be expected in any open group such as this to have a pile of people like me who try stuff just to see if it works before theory is understood, but don't get the cart ahead of the horse. Why I am saying this is so that everyone don't run out and build the first thing you see a picture of just because it looks like excellent workmanship. If it hasn't been proven yet, it hasn't been. Only because I have been there too many times. That being said, Excellent work Reggie. Your quality of workmanship is what I strive for. I am trying to find a source for the end housings so that my in house is not so labor intensive until I get the big CNC finished. Too many projects too little time but I have been waiting for such an opportunity for over 30 years. Can't wait for both of the DVD's to arrive so that the conference presentation (and more) can be absorbed again. Wayne

Wayne I'm setting up the electronic's right now and if it works I will put the end bells up on the forum at a low cost OK Reggie

[radiant1]

brushless motors

I know everything shown on the dvd's are comutator motors but can brushless motors be used?
Alan