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  • Peter Lindemann
    replied
    Your Misunderstanding

    Originally posted by nali2001 View Post
    Good videos! Nice and clear explanation. This will give the starter a good general idea what this is all about.

    One thing I must address though, I don't know how you controlled your attraction motor 20? years ago, but this one is in a sense a 'pulsed attraction motor' Your switching type does not care much for mechanical loads the pulse is always short, in a ("more true") attraction motor the coils will be powered aslong as it takes to get the rotor in alignment. So that mean that there will be a higher current draw per on-time at 3rpm then compared to 3000rpm since at 3rpm the coil will be on for like seconds. If we want to also have some considerable torque of these designs we must (in my opinion) make the system so that the coil will be on as long as is needed to get the rotor in alignment and not just a short blast. Maybe some reed pulse with variable pulse width. Or some opto controller sensing a wheel with holes that are as long as a rotor alignment stroke. I know it is not really necessary at this point but I noticed from my old flux-gate gen/motor tests that you also need control to advance or retard the on-time of the coil. Since at certain rpms the slowness of the steel start to become an issue with a fixed pulse on-time.

    Regards,
    Steven
    Steven,

    The magnetic reed does NOT just produce a fixed pulse. It stays on as long as the magnet on the wheel is in range. This means the "ON TIME" to "OFF TIME" ratio is the same regardless of speed! So, that does not cause the motor to draw more current at slower speeds, since the "Duty-Cycle" or percentage of "ON TIME" is always the same.

    The point of these motors is NOT to make them as powerful (mechanically) as possible! The point is to make them operate in a special window, to make them as EFFICIENT as possible, which means to harvest as much FREE MECHANICAL ENERGY as you can while still recovering the maximum electrical energy.

    The machine is a "balancing act" between the two outputs, as can be seen in the new videos. Tweeking the machine into this window will NOT make it produce its maximum possible mechanical energy. It will make it produce its maximum COP.

    If you just maximize your motor for torque, you will recover very little electrical energy, if any, and it will run like an off-the-shelf Switched Reluctance Motor. If that is what you want, then Great, but this is NOT what this project is about.

    Peter

    Leave a comment:


  • nali2001
    replied
    Videos

    Good videos! Nice and clear explanation. This will give the starter a good general idea what this is all about.

    One thing I must address though, I don't know how you controlled your attraction motor 20? years ago, but this one is in a sense a 'pulsed attraction motor' Your switching type does not care much for mechanical loads the pulse is always short, in a ("more true") attraction motor the coils will be powered aslong as it takes to get the rotor in alignment. So that mean that there will be a higher current draw per on-time at 3rpm then compared to 3000rpm since at 3rpm the coil will be on for like seconds. If we want to also have some considerable torque of these designs we must (in my opinion) make the system so that the coil will be on as long as is needed to get the rotor in alignment and not just a short blast. Maybe some reed pulse with variable pulse width. Or some opto controller sensing a wheel with holes that are as long as a rotor alignment stroke. I know it is not really necessary at this point but I noticed from my old flux-gate gen/motor tests that you also need control to advance or retard the on-time of the coil. Since at certain rpms the slowness of the steel start to become an issue with a fixed pulse on-time.

    Regards,
    Steven

    Leave a comment:


  • Peter Lindemann
    replied
    Aaron, Thanks for all your help!!

    Originally posted by Aaron View Post
    Hi all,

    Check out these 2 new vids on youtube:

    Part 1 Lindemann Rotary Attraction Motor 2a
    Part 2 Lindemann Rotary Attraction Motor 2b

    Each one is about 10 minutes long.

    There are 3 demo comparisons to show the difference between having the following 3 as loads:

    1. short circuit
    2. light bulb
    3. charging a battery

    You can clearly see the more you put on the back end, the less is taken from the input.
    Aaron,

    Thanks for posting these videos. I know you have put 10 times more work in editing and finishing these films that it took to shoot them at my shop last week. Your continuing support for the Electric Motor Secrets project has been fantastic!

    I hope they inspire more people to experiment along these lines.

    Peter

    Leave a comment:


  • Jetijs
    replied
    Thank you for these videos Aaron
    Great job Peter. This video is very encouraging, its almost seems like this is the easiest thing to do when you are describing this so good and easy to understand. This is the encouragement I needed

    Leave a comment:


  • Aaron
    replied
    New Youtube Videos of Attraction Motor

    Hi all,

    Check out these 2 new vids on youtube:

    Part 1 Lindemann Rotary Attraction Motor 2a
    Part 2 Lindemann Rotary Attraction Motor 2b

    Each one is about 10 minutes long.

    There are 3 demo comparisons to show the difference between having the following 3 as loads:

    1. short circuit
    2. light bulb
    3. charging a battery

    You can clearly see the more you put on the back end, the less is taken from the input.

    Leave a comment:


  • Peter Lindemann
    replied
    Steven, Great Pics!

    Steven,

    This motor looks very good. Now that I see the magnetic graph in the last image and see how you plan to run it, this could be extremely excellent. Just make sure you leave enough time for the stator field to fully collapse, and recover all of that electricity, before you turn the next set of coils on. If you do this, your motor should really perform well and prove out everything I have been saying on my DVD.

    Keeping the gaps as small as you have them will produce very large torques.

    Very, very good!

    Peter

    Leave a comment:


  • Jetijs
    replied
    Those are some nice pictures
    Thank you for sharing

    Leave a comment:


  • nali2001
    replied
    Motor

    Looking good Jetijs, Man I wish I had a CNC machine.

    Well now, I almost finished my test thingy. It is based on the idea I explained earlier, using existing cores from normal induction motors. only the housing and rotor is custom. Well the rotor is of solid steel and the axle is aluminum. I know the solid steel sucks big time since it will bust in to flames in minutes (due to Eddy Currents) I'm not joking either since I made a experimental generator with solid steel cores at one time and I tell you within 1 minute the cores was over 80 degrees celsius. (rpm doubled under full load though, but that is a different story) But anyway I guess it should be alright for short 'tests'. Extreme care is taken in precision machining. And so I can say that it has an 0.07mm airgap on each side. So a sheet of paper will barely fit. I also have taken metal expansion into account and measured that the rotor will expand like 0.05mm at about 100 degrees celsius. The bearing are conical 'self centering' rolar bearings. And due to the housing construction you can adjust the bearings in case it has some play in it. The stator is not wound at this moment.

    Kind regards,
    Steven






    Last edited by nali2001; 10-22-2007, 01:53 AM.

    Leave a comment:


  • Jetijs
    replied
    I guess it is true that if you want something to be done, you must do it yourself
    I finnaly solved the |==/ \==| problem.



    I did it just like Peter said. The hardest part was to locate the exact center of the circle (you can see that I was a tinny little bit off the centre, but that wont affect anything). When I found the centre then I just made my cnc mill rotate the grinding tool in circles, each time with a tinny little bit greater diameter, till I got a smooth finish
    I think that somewhere around next week I will be ready to assemble the whole thing. Then there will be only the coil winding left and the circuit part.
    Last edited by Jetijs; 01-19-2008, 12:57 PM.

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  • nali2001
    replied
    Mot

    Microwave Oven Transformer.
    Extreme Electronics - Tesla coil components

    Regards
    Steven

    Leave a comment:


  • Jetijs
    replied
    Steven, what do you mean with "Mot" ?

    Leave a comment:


  • nali2001
    replied
    Cores 'n coils

    Hi Peter,
    That is some hefty gauge you got going there! Any special reason why that is needed? Will pull some amps for sure. You are working with Mot cores right? Man I must have used over 10 Mots the last year... They make great cores for just about anything!

    Good work!
    Kind Regards
    Steven

    Leave a comment:


  • Jetijs
    replied
    Nice pics
    Peter,
    I spent all the time today figuring out how to solve the problem with my startor. There were several ideas that would require to build a mechanical device to solve this problem. Lastly I figured that I could just make a template of the startor plates with a hole in the exact center of the rotor. Then I could attach this template to the startor piece so that the tempate edges and corners lines up exactly like the startor edges and corners. This way I will have the exact point of refference to adjust my selfmade cnc milling machine. So I made the template out of a 3mm thick aluminum plate so that it matches the tartor plates exactly in dimensions.
    Now I have to attach this plate to the startor so that the edges are in perfect alignment. Then I will just move the endmill bit of my router to the little hole in the startor so that the endmill bit fits right in the hole. Then I will zero out all axis and this will be my X 0; Y 0 point. Now I will just have to replace the endmill bit to a suitable one and let my router go in circles, each time making the circle a tinny bit bigger
    What do you think?
    Thanks
    Last edited by Jetijs; 01-19-2008, 12:57 PM.

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  • Aaron
    replied
    pics of coils

    Hi everyone,

    Here are 2 pics of Peter's coils:



    Leave a comment:


  • Peter Lindemann
    replied
    Machining Operation

    Originally posted by Jetijs View Post
    Thanks Peter,
    I cant wait to see the pictures although I understand what you are meaning. I have now some other problems. The guys from the machine shop said that the startor plates are glued together forming kind a cone. I you imagine the startor piece and see at it from the thickness side then it would appear something loke this:
    |======/ |===rotor===| \======|
    I hope you understand. The upper startor plates are closer to each other by about 0.2mm. This means that the top rotor plates will be closer to the startor piece than the bottom ones. This is not good and I have to figure out how to deal with it, because they cant do the lathe work if the startor isn't right and they do not have the equipment to fix the startor. I already have some thoughts, but this will take time.
    Jetijs,

    The machining operation to fix your stator piece involves clamping it in a vise between two large blocks of aluminum for extra support, and then using a vertical mill with a boring head in it. The diameter of the cut can be dialed out slowly .0005" at a time. Extremely precise corrections can be made.

    Support the stator pieces as much as possible because the milling operation is an "interrupted cut." The set-up is the most difficult. Mounting the stator piece in the vice and then finding the exact center to begin the milling operation. The actual cut should take about 5 minutes. The set-up may take an hour.

    Too bad more care was not taken in the gluing operation.

    (Aaron should be getting those pictures posted soon.)

    Peter

    Leave a comment:

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