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Is this possibile to do with a alternator?

  1. Jun 22, 2012 #1
    A friend of mine sent me this link over from Youtube. I really doubt it a lot... But the numbers from that meter keeps telling me other wise...

    Basic idea: Added more and more layers of Neodymium magnets to improve the supposed "output". From 10W to 40W as he claims.However, the meter shown in the video ONLY measures the voltage in the system... W= I X V

    If this is truly possibile please give me a detailed explanation how this is possibile?(I honestly doubt it woud its possibile)

    A lot of wind turbine generators claim to produce a fairly good output with permanent magnets and with very low rpm's it can give out a very good output.


    NOTE*: IM NOT INTERESTED IN PERPETUAL MOTION OR ANYTHING THAT RELATES TO THAT, OBVIOUSLY MORE INPUT IS APPLIED TO THE ALTERNATOR*
     
    Last edited: Jun 22, 2012
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  3. Jun 22, 2012 #2

    sophiecentaur

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    Something you don't mention is the mechanical power that needs to be put into the alternator. From your figures, I would suggest that the engine supplying the power would need four times as much fuel per hour. Nothing magic, it's just that the alternator can transfer more power - just like another, entirely different alternator might. I suspect that the windings may get hotter than they were designed for - with possibly four times the design current going through them.
    How does it work? If you have more magnetic flux then the induced voltage would be expected to increase at any given rotation speed. But it will be 'harder' to turn the alternator.
     
  4. Jun 22, 2012 #3
    I don't mention the details and all please check out the link...
     
  5. Jun 22, 2012 #4

    sophiecentaur

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    I started looking at it but got bored with the presentation and the irrelevant start.

    Is it just a modification? What was the point? If he isn't making a proper comparison then it's a waste of time.

    What sort of comments do you want? You ask if it's truly possible but is 'what' truly possible?
     
    Last edited: Jun 22, 2012
  6. Jun 23, 2012 #5
    Well, he modified the output by adding more and more layers of permanent magnets and increase the output voltage. He used the same mechanical input over and over again and the only thing that changed was the output I thought that was a bit weird wasn't it? Adding a few more sets of magnets would increase the output?

    I'm asking that adding more permanent magnets into the generator's rotor would increase output power with the same input mechanical energy that is rated at (800 rpm). Thats what he is calming.
     
  7. Jun 23, 2012 #6

    sophiecentaur

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    I didn't see him doing any measurements of the power supplied or of the efficiency of the system, before and afterwards. It is not difficult to make an alternator with really low efficiency and then improve it.
    It was obviously fun to do but the experiment was so sloppy that it proves nothing and the results, which were claimed to be odd, don't need 'explanation'.
    You have to ask yourself why the Ford Motor Company or General Motors don't just do the same, if it's as easy as he seems to claim.
    I have seen faith healing, a lamb with a human head and over unity power generation on You Tube movies. I'm inclined not to believe any movie I see, without some backup evidence or authority.
     
  8. Jun 23, 2012 #7
    So far I've concluded that he has increased efficiency of a system and increase the power output by only increasing the amount of magnet and true there isn't much evidence to back him up. However, from what you're saying it nothing new and many people have done it before so I can increase the output of an alternator's "current" by increase the amount of efficiency and one method is increase strength of the permanent magnates in that alternator to add MORE force on the coils to supply more "current".

    I try to research this more and more not on Youtube obviously because its enough they have over 1000+ videos about perpetual motion and non-sense like that and free-energy that they understood wrongly.
     
  9. Jun 23, 2012 #8

    sophiecentaur

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    All he has demonstrated is increasing the output power. He hasn't measured power in so we can't even be sure of the efficiency.
    All things being equal, if you increase magnetic flux, then the induced emf at a given speed would go up. But that says nothing about the power situation. There's just not enough info here to discuss seriously.
    But you can be sure that there are no challenges to basic theory - just some increase in a quantity in an experiment.
     
  10. Jun 23, 2012 #9

    jim hardy

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    Whatever portion of the magnetic flux is made by the "permanent magnet part " of the field does not have to be made by the "electromagnet part" of the field.
    So he saved a tiny amount of the electrical energy that's fed into the rotating electromagnet that is the alternator's field.
    I would guess on the order of a watt.

    Rest assured the electrical power output from the alternator remains less than the mechanical power input to it.
     
  11. Jun 23, 2012 #10
    there was no electrical energy inputed to the electromagnets? Mechanical energy was fed to the rotor that had permanent magnets attached.

    The of the video is this: Increasing more permanent magnets to the system would increase the OUTPUT with the same INPUT as before. And the input is ONLY mechanical using the screw drive to drive the rotor. What his showing is only the volt meter increasing its voltage by increasing the amount of permanent magnets to the rotor. 10W to 20 to 30 finally 40W
    the voltage is 40, so the current is 1 AM.

    I was asking if this modification is correct that's all. I haven't really understood all you're post clearly if you could "dumb it down" just a bit that would be great.


    And yes. The input will always be greater the the output so no need to mention that point thanks though.
     
  12. Jun 23, 2012 #11

    sophiecentaur

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    @DreamChaser
    You seem reluctant to accept that there is nothing 'special' about that very sketchy demonstration. Why?
    There are two factors governing the output power of an alternator. One is the efficiency and one is the power input.
    Having a strong field gives better efficiency than having a weak field but there are limits to what you can actually achieve because you have to have gaps in the magnets to allow movement and the inductance of the windings will limit the rate of change of current. There's nothing philosophical in this - it's just a matter of realistic design. If there happened to be room in that alternator to fit extra magnets then it clearly didn't have optimal design but was probably built to a price. (That's engineering for you)
    Also, that video does not show, in any way, that the input power is the same with and without the magnets. Where is the power meter? He just attaches an electric drill to drive it. Also, it doesn't actually have a power meter on the output either.
     
  13. Jun 23, 2012 #12

    jim hardy

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    I'm sorry - i wasn't able to make the video play so i assumed he had an automobile alternator. My bad. I'm havibg trouble with my video player software.

    If the field was all permanent magnet, no electromagnet, then the only input to his machine is as you said, mechanical.

    Mechanical power into a rotating machine is in proportion to product of torque and speed, just as with linear motion it's product of force and speed.

    In English units, horsepower = 2 X pi X torque(ft-lbs) X RPM / 33,000
    (the 33000 is there because 1hp = 550 ft-lbs per sec or 33,000 ft-lbs per minute)

    Was there a torque meter on his apparatus?
    If not then he didn't measure mechanical input power.

    At a given speed voltage will be in proportion to flux,
    so if he added flux by more magnets he increased voltage allright
    but power out still = power in - losses so any increased output came at price of increased input torque.

    Did he measure torque? Real machines are tested on a "dynamometer" which measures torque. You can make a simple one from a spring scale like the ones for weighing fish.

    old jim
     
  14. Jun 24, 2012 #13


    He had a volt meter attached to the output. The input was the same since the electric drive was rated at 800 RPM and the output changed.

    So far... I can answer my own question and say that increasing more magnets would lead to a major increase to efficiency.

    I got the idea well. Thanks all
     
  15. Jun 24, 2012 #14

    jim hardy

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    800 RPM at how much torque?

    Efficiency = output power / input power

    Efficiency = (output volts X output amps / 746) / (input speed X input torque X 2pi / 33000 )

    You said he had a voltmeter on output and speed was 800 RPM, so there's just two unknowns left - output amps and input torque.
    Did he measure both ? If not he has no idea of efficiency.

    not by any practical definition of efficiency.
     
  16. Jun 24, 2012 #15

    Averagesupernova

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    So 800 RPM is mentioned but no mention of torque? Sorry, can't specify actual power input without knowing what the torque is. You can jump up and down all you want to about increasing magnets. Simple fact is that adding magnets will cause a conductor to cut through more/denser magnetic fields per rotation. I am sure you will not argue with that. Are you also realizing that the denser/more magnetic fields that are cut during power generation will cause more back torque on the alternator? Hmmm, there is where that torque thing comes into play that I mentioned. If your claim is that extra magnets will not cause more back torque then you are contradicting the claim you made in your first post:
    -
    If adding more magnets doesn't affect input torque then why can't we continue adding magnets until the output power exceeds the input power? The truth is you can't because it goes way back to that conductor cutting the magnetic field thing where the conductor develops a back torque, EVERY TIME!
     
  17. Jun 24, 2012 #16

    sophiecentaur

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    @DreamChaser
    You asked our opinion but have argued against an undivided one. Why did you not accept it?
     
  18. Jun 24, 2012 #17
    Well, he did not supply us with that information about the input torque nor the output current.

    I knew there would be counter torque but never really understood it that much... All I know is if you add more magnets to the system and current is drawn from it, if there is more and more magnets there will always be more counter torque...

    I'm not arguing. I want to you're opinion and understand whats going on.
     
  19. Jun 25, 2012 #18

    sophiecentaur

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    But the point about input power was made several times before you acknowledged it. That seems like arguing to me. This thread could have been wound up many posts ago if you had read what people were telling you.
     
  20. Jun 25, 2012 #19

    Averagesupernova

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    If you knew there would be more back torque then how can you say that efficiency goes up like crazy? Did you not realize that torque is needed to know input power?
     
  21. Jun 25, 2012 #20

    russ_watters

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    Considering that it has been explained to you multiple times, including by me, that generators are already very efficient, making "a major increase to [sic] efficiency" impossible, it does not appear that you have any desire to learn here, so this thread (and similar ones) will continue to go nowhere. Locked.
     
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