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Electric Motor Secrets

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  • Aaron
    replied
    Free Energy

    Peter put up some new resources on his website...just got vamped quite a bit.
    Free Energy

    Anyway, just an update.

    Leave a comment:


  • uusedman
    replied
    Jetis,

    Thank you for your humble and informative answer. 2 motors can feed each other, when one is working and recycling the induced charged it can be applied to the 2nd motor when it is ready to fire.

    Leave a comment:


  • Jetijs
    replied
    Hello uusedman
    I have already explained the reason of two motors working as one in my previous posts. The big idea is that V2.0 showed efficiency go up as the motor was loaded, but loading the motor also did slow it way down and this is mostly because the motor is not ON 100% on the time, it is only ON about 240-260 degree per revolution, all the remaining time it just rotates forward by its own inertia. And it is in this inertial movement, when the motor can be slowed down considerably. So I though that if the motor is ON all 360 degree of a rotation, I should be able to load it and not loose much in speed. Since this type of motor needs a "time to breathe" between pulses for recovery, it can not be made to operate at 100% ON time. That is why I need two motors with out of phase rotors. This way when one motor is doing work, other is resting and vice versa. That way we can get 100% ON times or even more, because the stator/rotor geometry allows ON time overlaping.
    Hope this helps

    Leave a comment:


  • uusedman
    replied
    This question will certainly be out of place however, i am curios to know why you using 2 motors? Is it part of the project to recycle the energy from one and give to the other and vice versa?

    PS your work is awesome and motivational.

    Leave a comment:


  • Jetijs
    replied
    Mark, the circuit I posted above was used in motor V2.0 and it had IRFP450 MOSFET's, now I will use IRFP360 MOSFET's, because thay can handle higher currents.

    Leave a comment:


  • Mark
    replied
    Are you using the 360 or the 450 mosfets
    Last edited by Mark; 02-13-2009, 08:40 PM.

    Leave a comment:


  • StevanC
    replied
    Originally posted by Jetijs View Post
    (snip)

    Stevan, those switches are too small and have a too small gap. They can not be used in this case

    Thanks,
    Jetijs
    ok,
    I didn't realize the scale of the unit until recently :-)

    I like it more and more , keep it up!

    the cost is paramount to me (hobby builder) an I just found that used power supply fans make a great base for this stuff, so the size of an salvaged opto switch from a mouse could play for me.

    I hope You "YouTube" it ASAP?

    Leave a comment:


  • Jetijs
    replied
    There is no PWM circuit on that board, just a simple drive circuit with a MOSFET for each coil. Four coils per motor. Here is the circuit from V2 motor:



    This circuit was intended for only one motor with opposite coils in series, so only one transistor per two coils. Now I am using the same circuit, the only difference is that there are two such circuits on a board and each MOSFET driver triggers two MOSFET's in the same time. The ON time chopper circuit will be installed later.

    Leave a comment:


  • cody
    replied
    Looks like you are using a PWM circuit to chop up your pulse on time to a higher frequency, why did you decide to use four separate ones instead of just one? This is a great idea to do that, ive been playing with it myself.

    Leave a comment:


  • Jetijs
    replied
    I am working on the circuit now.
    I decided to use IRFP360 MOSFET's, because they have better current ratings. They are rated 400V max, so I used 400V transil diodes to protect the MOSFET's. This way anything higher than 400V will go through the transil diode to the ground. I use UCC27321P MOSFET drivers, one for each pair of coils. The output of each MOSFET driver goes to two MOSFET gates in parallel. That thing on the upper left side of the circuit board is a 7812 positive voltage regulator that converts input voltage from up to 35V to 12V for the circuit logic and optoswitches. When everything is ready I will post the circuit diagram.



    Thanks,
    Jetijs.

    Leave a comment:


  • LowTechIsCool
    replied
    Here in Pullman, WA

    Aaron,

    I am planning on using it for my senior research project, next year. I will be having a number of people working on it.

    Right now, I am building a motor to understand the process. Then I plan to make a better one next year.

    -Chris Corkum

    Leave a comment:


  • Aaron
    replied
    Wsu

    Hi Chris,

    When your motor is done, is that something you're going to demonstrate at WSU...down in Pullman right?

    Leave a comment:


  • Jetijs
    replied
    Another update. I got my optoswitches today and finished the motor. So now whats left is the driving circuit.



    Chris,
    So far I can not give you any data about the inductance, but remind me again when the motor is up and running. I use SKF 2200ETN9 double row self aligning bearings.


    Have You ever considered opto-switches salvaged from old 'male' (ball type) computer mouse ?
    Stevan, those switches are too small and have a too small gap. They can not be used in this case

    Thanks,
    Jetijs
    Last edited by Jetijs; 02-07-2009, 10:16 PM.

    Leave a comment:


  • LowTechIsCool
    replied
    Inductance Vs. rotor position

    @broli
    Your approximation of the inductor/capacitor circuit is what I imagine, except that the inductor value is changing, since the rotor position is changing.

    As the rotor spins to center, the inductance is changing, decreasing?, and that means the amount of energy on the coils is decreaseing. If you forcibly rotate the rotor away from center you will increase the energy on the coils and you have a generator, at least i think so.

    From this i imagine that we would like to to get our pulses to be a short as possible.

    @jetijs
    I am very busy right now with school, so it will be at least a month before I complete my motor. In the mean time I was hoping jetijs could give me some readings from his motor.

    I was hoping that you could get some data on the time constants of the coils at different positions. That is the amount of time for the potential, of a fully charged coil, to drop by a factor of (square root of two) when it is shorted. The time constants can be taken when the rotor and stator are aligned, then when they are completely unaligned. If you can get more values in between that would be better, but you would need some kind of brake, since when you turn on the coil the rotor wants to rotate.

    From the time constant i can figure out the inductance with respect to position and should be able to model the circuit. This should give some insights into timing, at least for me.

    Finally, can you give me a make/model of the bearings you use?

    Thank you,
    Chris Corkum

    Leave a comment:


  • StevanC
    replied
    Originally posted by Jetijs View Post
    Hi StevanC,
    so far I am waiting for optoswitches to arrive, they should be here next week.
    What do you mean with benchmarks?
    1stly, I want to congratulate You a excellent build :-)

    I really like it :-)

    further, i hope You won't stop just by building it?

    You will make some sort of benchmarks and tests?

    I look forward to it, and testify there are people who would like to encourage You in Your effort



    I would like to get this far with my build(s), but obviously am to lazy to make even photos and reports :-)
    Have You ever considered opto-switches salvaged from old 'male' (ball type) computer mouse ?
    I just wonder?

    Leave a comment:

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