Electric Motor Secrets

[Peter Lindemann]

Next Step

Jetijs,

Apparently, you would like to abandon the magnetic reeds and move on to the opto-interrupters. Without a thorough study of what happened, you will never know. I believe the problem is with your magnets, the aluminum wheel they are mounted in, and the steel bolts nearby causing field distortions. In my estimation, you have not actual learned WHY the magnetic reeds are misbehaving at this stage of testing.

OK. On to the optical approach. As I said in an earlier post, the difficulty with this method is in the intermediate stage. The Data Sheet on the ITR8102 states that the photo-transistor output stage can only handle 50ma of current and a maximum C-to-E voltage of 30volts. This current level is insufficient to drive three output transistors directly.

As you can see, a number of different suggestions have already been made. Any of them can be made to work to one degree or another. Each solution will have its own issues. My suggestion is that you stay with the Bi-polar Transistors for now and go with one stage of signal amplification in between the photo-transistor and the power transistor.

The system I use is quite simple. Replace the magnetic reed switch with a medium power PNP transistor. So, the first stage of control will remain similar to what you had with the reed switch. The emitter of the PNP is connected to the Positive Supply and the collector is connected to the first resistor in the voltage divider. The base of the output transistor is still triggered between the two resistors of the voltage divider.

Next, we are going to create a second voltage divider operated from the NPN photo-transistor. So, the emitter of the NPN photo-transistor is connected to the circuit ground (negative of the supply) and the collector is connected to the first resistor of this new voltage divider. The second resistor connects to the Positive Supply and the mid-point between the resistors connects to the base of the PNP. So now you have positive control of your POWER NPN through one inverted stage of signal amplification. The resistors in the voltage divider operated by the photo-transistor can be 2k ohms each, or higher and still be sufficient to turn the PNP on quickly and completely. Just keep the total current in this section below half of the rated current maximum of the photo-transistor, or about 25ma.

Set this system up for one power transistor and one coil. I suggested in an earlier post that you run some tests with the values of your primary voltage divider to see how much higher the resistor values can be raised above your currently used 200 ohms and still get clean switching of your power transistor. See if the transistors switch cleanly with 680 ohm resistors. If they do, then just make two more voltage dividers to run two more power transistors to run the other two coils. Parallel the voltage dividers and run them all from the collector of the PNP.

Make sure you have an output diode on each of the coils when you test the system.

Good luck,

Peter

[lighty]

@Jetijs

It would be better to use opto-reflective switch since then you will only need to have one disk with reflective surface and you could simply change your timing with a bit of a non-reflective paint. No need for any slot or additional machining. On the other side the electronics would be more complex because of the need to control the levels of the photo-transistor in cases of the changing reflexivity. So, in my opinion you should stick with photo-interrupter switch for the moment.

Also, it would be easier to drive MOSFET- they are basically driven by voltage rather than by current so they're simpler to work with in logic circuits or in this case in switching circuit. IRFP450/460 comes to mind since they're rather common and not expensive. Also, when driving MOSFETs with voltage it would be harder to burn out your opto-interrupter switch (not impossible though).

I usually use much more complex circuit topology since for various reasons I need to have my signal conditioned, cleaned, pulse response advanced and to ensure extremely fast switching with advanced control I use MOSFET driver ICs. You don't need all that so the schematic I suggest is the following.

Please note that the first schematic has an inverted logic - that means that when the photo transistor is active (when the slot allows for the passing of light) the MOSFET will act as an open switch.

If you want MOSFET to conduct current when the slot is passing the light then simply use the second schematic called "non-inverted" (it has one bipolar switch added in order to invert the signal logic and also to ensure better control over MOSFET- in my experience for this simple application a small transistor like 2N2222 or BC635 or something like that that you can get your hands on).


As for the values of the resistors it can easily be calculated when you specify the exact voltage you'll be using. Also, if the inductive collapse voltage should exceed semiconductor switch maximum rating you can easily add some fast transil diode in parallel in order to protect the device- the drawback is that if the protection diode conducts the most of the recovered energy will be grounded (but at least it will protect your semiconductor until you come up with some solution for the problem). For example the good old 2N3055 is rated about 70V CE voltage and anything higher than 80-90V would probably kill it. 2N3584 would be much better choice because IIRC it has about 250-300V CE voltage rating but I'm not sure about it's current capability (did you measure the power consumption of the coil) since I didn't look at the datasheet yet.

Anyway- I suggest you use MOSFET since it's much easier to work with (although not without it's quirks when working in more severe electrical conditions) but Peter might suggest otherwise. I guess you should listen to his advice- he's the chief of this parade anyway.
All you need to do is to replace MOSFET with BJT power transistor and add another resistor between base and emitter to ensure proper shut-down.


P.S.
Why do you need to machine a new disk every time- why don't you simply mask out the slot (if you need narrower slot) with some cardboard and adhesive tape?

P.P.S.
Since you've asked about whether your circuit would work the answer is most likely but it depends a lot on the power ratings of the opto-interrupter transistor. I will look at it more closely tomorrow, it's almost 4AM and my brain is shutting down.

[Jan H]

with my little electronics knowledge i can't see any mistakes in the circuit.
I do wonder though, if those little triggers can switch the transistor directly. I would risk only one of the triggers first, see what happens.
I know a lot about frying parts, because im a master in doing that

can't wait to see it running, especially since i ran out of parts, so cant do anymore testing myself.

[Jetijs]

Peter,
thanks for the suggestions. The reed witches did work after I froze them and heated up several times, but I still could not get the perfect timing. I could either get two pulses perfect, one a tinny bit off and the third pulse wont fire, or one pulse perfect with other three pulses way off. I tried to center the timing wheel but with no luck, if I move a reed switch near enough the magnets I can get all the pulses, but they are not equal in pulse width. When I move the reed switch just a half of millimeter away, I can get only three pulses. Yesterday I spent all day adjusting and readjusting the timing, I tried three different timing wheels - no luck. The problem is in my method of attaching the timing wheel to the shaft:


As you can see it is only bolted to a thread in the shaft end through three
6mm thick aluminum spacers. No bolt is gonna be precise enough. It's a shame I did not think more about the timing when making the shaft, I would made it better I know the reed switch would work well for this purpose, but due to my bad job on the shaft, I have to consider different switching methods. I really want to get the motor working and I have already spent too much time with reed switches and no luck. The first try was good, but also there the timing wasn't exactly very accurate. So I went to local electronic shop today to buy some more 2N3055 transistors and also bought some optointerrupters, they had only two pieces of ITR8102. They were very cheap, so I bought both of them. Here is the data sheet:
ITR8102 pdf, ITR8102 description, ITR8102 datasheets, ITR8102 view ::: ALLDATASHEET :::
The gap fo the optointerrupter is 3mm wide, so I made a timing wheel out of 2mm thick aluminum. The wheel is designed so that there will be 4 pulses at 90 degree angles, each one 15 degree in duration (exactly half of the rotor leg width). If this wont work well, I can make new timing wheels easy in the matter of minutes. Also the gap of the optotrigger is deep enough to allow that little off center I have.



I figured the circuit should be something like this:


Of course I am not sure if this optotrigger will handle more than one transistor this way. Maybe I need this second stage amplifier. In that case I have some small 2N3584 transistors, just like in the John Bedini's cap pulser setup, where these transistors are used to trigger the SCR. Maybe I can use that? Here's a data sheet:
2N3584 pdf, 2N3584 description, 2N3584 data sheets, 2N3584 view ::: ALLDATASHEET :::
I think It shouldn't be a problem for me to solder it all together, I have some experience on that (have built some cap pulser setups). I just need to verify that the circuit I drew is correct and if someone has any comments about this. I intend to power the motor from 24V with two batteries in series.

Thank you all
Jetijs

[Peter Lindemann]

Lenz Law in reverse....

This is just an idea I had. It won't make your attraction motors any more powerful, but it will insure that you use a minimum of power. I have additional circuitry to add after I nail down what appears to be the best methods. The additional circuitry will be addressing the issue of applying the peak magnetic field to the optimum armature position. This will require an automated method of advancing the timing for the drive pulse. The attached schematic is crude and buggy, but should give you an idea of what I'm trying to achieve.

Dear Ewebie,

Yes, I understand what you are trying to say. The idea is to keep the inductance low so the rise-time of the current is extremely fast. The magnetic field can then be produced by a very short burst of current. Then just shut off the input current and short-circuit the output. The magnetic field wants to collapse instantly, but generates a current that opposes the change in flux, which in this case sustains the magnetic field longer for no additional power input. During this "free field sustaining" period, the magnetic field can still be attracting the rotor piece to the stator core, producing "free" mechanical energy.

This "little trick" is part of what Bob Teal was doing in his Magnipulsion Engine. He used two coils in parallel controlled by a single switch. In this arrangement, the two coils charge up in parallel, but then try to discharge into each other in series, thereby sustaining the field for much longer than the time it took to create it.

There are many such "tricks" that can be employed in these motors to get "free" mechanical energy production. Thanks for bringing this up.

Peter

[Peter Lindemann]

No Real Problems...

Dear Peter,

You grossly misunderstand my intentions. I have nothing but a highest level of respect for you and everything you have done in your career so far. In fact it was one of your articles regarding MWO that you wrote for BSRF that got me interested in this field in the first place. For that, I am deeply grateful to you.

I am truly sorry if you got the feeling I'm being competitive and nitpicking. I never intended to antagonize anybody on this forum and least of all you. I am well aware that this is but a side project and to be honest I was much more interested in what you have to say about the radiant energy. I am also well aware that you simply cannot share most of your knowledge for various reasons I can think of. However, everything you wrote on this forum was carefully read by me and I did take some of the experiments of my own to verify some of your assertions. So far you've been right in almost everything you said- the rest I suspect is simply the lack of the full disclosure by you. Again, I have to emphasize that I do appreciate everything you do share and I wouldn't want you to feel I put any pressure on you on that regard. I'm also payed to do some engineering of the stuff that's protected under NDA. It has nothing to do with free energy but I do understand the need to share some knowledge and being prevented to do so.

It's the engineer in me who is getting restless on watching somebody having trouble with inadequate parts. I truly didn't mean to score any points by stating publicly that reed switches are inadequate. I mean- when you have to freeze and thaw parts in order to get them to work that's when something in me get itchy to solve the problem. In this case the best solution would be optical switching. That's all. I'm not doubting your engineering skills. I'm not doubting your engineering wisdom. I also don't doubt for a second this thread is yours. But something I won't do is listen without raising any questions or seeking some arguments from the person making some assertions. Reed switches are not adequate. It's that simple. I already said to Jetijs I will send him parts and schematics for optical switching system.

I'm truly sorry I currently simply don't have any spare time to try reproducing your design and see in practice what I could do with the energy recovery. I have some practical knowledge of manipulating radiant energy and I don't mean SG stuff but some rather bizarre stuff that my colleague Shad and I stumbled upon while looking for something completely different. However, I'm eager to see where this project of yours will go. You're so far ahead of me that I'm not ashamed to say that I'm but a beginner comparing to you. You also did some interesting stuff with Bedini and he is another one of the people that I highly appreciate because of his engineering skills and diversity of projects he was involved with.

That being said I also respect the fact that you're twenty years older than you and have immensely more experience than me engineering-wise and I suspect life-wise. However please do allow for people to question some of your decisions. I always provide valid engineering argument why I think something should be done differently and ultimately more easily and I never do it for the sake of feeding my ego.


Respectfully yours

Zvonimir

Dear Lighty,

You and I don't have any real misunderstandings. Your comments are usually insightful and helpful. Please keep your comments in this forum on technical subjects and refrain from making any personal comments about whether you agree or disagree with what I am doing (or anyone else, for that matter). Just add your knowledge and experience and everyone will be grateful, including me.

As for optical commutator circuits, I agree that they are more precise in their ability to control timing. But for beginners, they also present subtle difficulties. I have never seen one optical commutation circuit that didn't need a second stage amplifier to bring the signal up to the level of being able to actually switch the primary device. So while precision in signal timing is attained, other control issues arise in the intermediate circuit that must be solved.

I never assume that people in these forums have sufficient electronic circuit design skills to just do the kinds of things that may be second nature to you. That is partly why I was trying to help Jetijs use his magnetic reeds. Also, I wanted to use the opportunity to help him solve his "unknown" problem and find a solution. This is good training, regardless of what the issue is.

As far as I am concerned, this little "misunderstanding" between us is over.

Best wishes,

Peter

[ewebie]

This is just an idea I had. It won't make your attraction motors any more powerful, but it will insure that you use a minimum of power. I have additional circuitry to add after I nail down what appears to be the best methods. The additional circuitry will be addressing the issue of applying the peak magnetic field to the optimum armature position. This will require an automated method of advancing the timing for the drive pulse. The attached schematic is crude and buggy, but should give you an idea of what I'm trying to achieve.

[lighty]

Dear Peter,

You grossly misunderstand my intentions. I have nothing but a highest level of respect for you and everything you have done in your career so far. In fact it was one of your articles regarding MWO that you wrote for BSRF that got me interested in this field in the first place. For that, I am deeply grateful to you.

I am truly sorry if you got the feeling I'm being competitive and nitpicking. I never intended to antagonize anybody on this forum and least of all you. I am well aware that this is but a side project and to be honest I was much more interested in what you have to say about the radiant energy. I am also well aware that you simply cannot share most of your knowledge for various reasons I can think of. However, everything you wrote on this forum was carefully read by me and I did take some of the experiments of my own to verify some of your assertions. So far you've been right in almost everything you said- the rest I suspect is simply the lack of the full disclosure by you. Again, I have to emphasize that I do appreciate everything you do share and I wouldn't want you to feel I put any pressure on you on that regard. I'm also payed to do some engineering of the stuff that's protected under NDA. It has nothing to do with free energy but I do understand the need to share some knowledge and being prevented to do so.

It's the engineer in me who is getting restless on watching somebody having trouble with inadequate parts. I truly didn't mean to score any points by stating publicly that reed switches are inadequate. I mean- when you have to freeze and thaw parts in order to get them to work that's when something in me get itchy to solve the problem. In this case the best solution would be optical switching. That's all. I'm not doubting your engineering skills. I'm not doubting your engineering wisdom. I also don't doubt for a second this thread is yours. But something I won't do is listen without raising any questions or seeking some arguments from the person making some assertions. Reed switches are not adequate. It's that simple. I already said to Jetijs I will send him parts and schematics for optical switching system.

I'm truly sorry I currently simply don't have any spare time to try reproducing your design and see in practice what I could do with the energy recovery. I have some practical knowledge of manipulating radiant energy and I don't mean SG stuff but some rather bizarre stuff that my colleague Shad and I stumbled upon while looking for something completely different. However, I'm eager to see where this project of yours will go. You're so far ahead of me that I'm not ashamed to say that I'm but a beginner comparing to you. You also did some interesting stuff with Bedini and he is another one of the people that I highly appreciate because of his engineering skills and diversity of projects he was involved with.

That being said I also respect the fact that you're twenty years older than you and have immensely more experience than me engineering-wise and I suspect life-wise. However please do allow for people to question some of your decisions. I always provide valid engineering argument why I think something should be done differently and ultimately more easily and I never do it for the sake of feeding my ego.


Respectfully yours

Zvonimir

[Peter Lindemann]

To Lighty

@Jetijs

Been there, done that- that's why I said that the only real and reliable solution is the optical switch. Mechanical contacts would be even more of a nuisance than the reed switches.

@Peter

With all due respect I don't really understand why are you still insisting on using the reed switches when it can be easily and elegantly solved using the optical switching? What's more, although I won't share those particular schematic publicly I will share them with Jetijs since it's obvious he will use it for some actual work. Same goes for you- if you want it I can send it to you as well (although I don't think for a minute you're not perfectly capable of engineering some of your own).

BTW- the whole system will cost less than 10-15 EU.

Dear Lighty,

I like you. I respect both your knowledge and experience. But right now, quite honestly, I find your ATTITUDE rather competitive and interruptive. This is neither your thread nor your model. I have always agreed with you that ULTIMATELY, Jetijs' motor will need an optical commutation system. But jumping right to the end without understanding why doesn't help anybody. I wanted Jetijs to LEARN from his experience. I was willing to guide him, step by step through the process of getting his motor running with WHAT HE CURRENTLY HAS all the way to full operation with a COP=2. This will require MANY changes beyond the commutation system. To optimize the motor, he will be able to salvage the stator core. But the motor will eventually need different coils, different commutation, different energy recovery circuits, and a new rotor to close the air-gaps. I wanted him to discover WHY each of these changes needed to be made so he could really understand the motor, inside and out.

You grossly underestimate my knowledge and my patience to let people learn from their own experience. Why do you NEED to jump in and be the one who KNOWS the answer for someone else? Why do you have to criticize me because I am trying to help Jetijs learn what his motor is doing STEP BY STEP? The most important lesson that anyone can learn is to learn how to see what is important, to focus on the essential!

I have NEVER insisted that Jetijs use the reed switches. I merely suggested he get the motor running with what he had on hand BEFORE spending any more money. There is plenty to learn with what he has, and that is what I am interested in.

I am involved in a number of projects that may start occupying ALL of my time within a month or two. At that point, I may stop participating in this forum (and all of the other forums as well). Who is going to help these people then? You?

I'm 56 years old and have been involved in this field of research since 1973. I don't know everything, but I have studied dozens of energy systems in the last 34 years and have a fairly broad view of the field. These electro-magnetic systems are interesting, but are NOT the most important energy systems I am working on.

Quite frankly, I find it boring and petty of you to be bothering to nit pick at me about optical commutators. If you want to give Jetijs a design for one, please do. But don't make such a big production out of it. If he builds what you suggest, he will learn what it does. But no matter how magically fantastic your optical commutator design is, it will still not save him from needing to make other changes later to correct other issues. So, what is the point? What is the big emotional push inside you that makes it OK to criticize me, and use the "optical commutator" as the excuse!

Peter

[lighty]

@Jetijs

Been there, done that- that's why I said that the only real and reliable solution is the optical switch. Mechanical contacts would be even more of a nuisance than the reed switches.

@Peter

With all due respect I don't really understand why are you still insisting on using the reed switches when it can be easily and elegantly solved using the optical switching? What's more, although I won't share those particular schematic publicly I will share them with Jetijs since it's obvious he will use it for some actual work. Same goes for you- if you want it I can send it to you as well (although I don't think for a minute you're not perfectly capable of engineering some of your own).

BTW- the whole system will cost less than 10-15 EU.

[Peter Lindemann]

Magnetized Reed Switches

Hello everyone.
I must say, that I had nothig but trouble with the motor last days. My bearings are junk and the reedswitches also behave weird. I tried a one magnet comutator with four reedswitches, I could time two reedswitches precisely, but the other two just wont switch, no matter how near I put them to the magnet. But when I disassemble the whole thing, the switches seem to work fine. I just tried my first setup with four magnets and one reedswitch, but now in order to get the switch to fire I have to move the reedswitch so near to the magnet that they are almost touching. I am confused. Could it be that the magnetic field from the strong neo magnets has magnetized the tinny steel parts of the reedswitch and thats why it behaves so?

Jetijs,

Yes, that is what I believe is happening. I have seen it with some of my reed switches as well. If the little neo magnets are left in alignment with the switch for days when the motor isn't running, they tend to cause a residual magnetic clamping action in the switch. Take the reed switches and put them in the freezer for 5 hours and then thaw them out. See if that helps release them. Or try the opposite, by putting them under a heat lamp for a few hours.

This problem happened to the magnetic reed on my demo motor on the YouTube Videos, and freezing/thawing released it. The main thing is, they can be recovered, so don't throw them away.

I think using four different reeds with one magnet on the wheel is always going to cause more problems. I suggest that you find the reed that works the best and use that one. Then put your time into spacing the magnets on the wheel properly so that each one triggers the reed the same way, which is the way you used the first time.

The idea here is to solve ONE PROBLEM at a time.

Keep up the great work!

Peter

[Jan H]

Jetijs,
that sucks! i share your pain. I know how frustrating it can be when a lot of hard work turns out to be for nothing.
Maybe you should get rid of the whole reed switch setup? would certainly make you feel better
how about plain simple contact points like in a car?

[Jetijs]

Hello everyone.
I must say, that I had nothig but trouble with the motor last days. My bearings are junk and the reedswitches also behave weird. I tried a one magnet comutator with four reedswitches, I could time two reedswitches precisely, but the other two just wont switch, no matter how near I put them to the magnet. But when I disassemble the whole thing, the switches seem to work fine. I just tried my first setup with four magnets and one reedswitch, but now in order to get the switch to fire I have to move the reedswitch so near to the magnet that they are almost touching. I am confused. Could it be that the magnetic field from the strong neo magnets has magnetized the tinny steel parts of the reedswitch and thats why it behaves so?

[sykavy]

Today I tried to run the motor form 24v (two 12v batteries in series). I must say, that the motor runs a lot smoother this way. Because when I run the motor form variac, the motor changes speed in a wave fashion, it slowly decreases and increases the RPM's, also the amp draw behaves in the same fashion. I think, that this is because there is some ripple in the DC current from variac, that my smoothing capacitors are not able to handle. That is why the motor runs smoother when powered form batteries with a perfect DC.
Thanks Steven, you were right

Jetijs congrads!! Great work!

I think your multiplane structure could be a good way to make the "S" rotor in Peter DVD. I could give the strength needed because Peter said the arms could be drawn out if not designed well. Anyway keep up the good work!

[Jetijs]

Today I tried to run the motor form 24v (two 12v batteries in series). I must say, that the motor runs a lot smoother this way. Because when I run the motor form variac, the motor changes speed in a wave fashion, it slowly decreases and increases the RPM's, also the amp draw behaves in the same fashion. I think, that this is because there is some ripple in the DC current from variac, that my smoothing capacitors are not able to handle. That is why the motor runs smoother when powered form batteries with a perfect DC.
Thanks Steven, you were right