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Small electric generator, driven by a small engine shaft

  1. Sep 29, 2006 #1
    Hello all, I'm new on the forum and will be spending a lot of time here i'm sure, as I am starting a senior design project for my electrical engineering degree.

    I was wondering if anyone was familiar with a small electric generator, that can be powered by a small RC engine, similar to this..

    I basically need to get a voltage out of a generator, but only have gasoline as my source of power (the gas engine.)

    Any and all suggestions are greatly appreciated!
    Last edited by a moderator: Apr 22, 2017
  2. jcsd
  3. Sep 29, 2006 #2


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    This is what I get when I click your link:
  4. Sep 29, 2006 #3


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    Ditto that.
    I don't know what size of engine you mean. There are definitely small generators out there, but I don't know if they're suitable for running from something like that. I'm thinking specifically of the type that we used to have on our bicycles that was driven by a friction wheel on the tire and used to power a headlight and taillight. I think that they put out about 6 volts.
    Last edited: Sep 29, 2006
  5. Sep 30, 2006 #4


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    Linky no worky.

    What does your project actually entail? There are hundreds of small, gasoline powered electricity generators available currently. What does your project require you to design?
  6. Sep 30, 2006 #5
    most DC motors will work as a generator
    as long as it has magnets and brushes
    gear/pullys to get right volts at a given rpm
  7. Oct 17, 2006 #6
    don't know what hp. motor you have.
    any Electrical Motor AC can be used as a generator. any motor from small fan motors and up (don't need to be brush type )
    if the motor has a ating of 120 volt @ .10 amp turn the motor at the motor rated rpm. it will genertor 120 volt @ .10 amp.
    if the load is to large, the output will just drop to zero volts
    just a note
    if you have a 5hp gas motor it will drive a 3 hp elec motor single phase or three phase
    hope this helped
  8. Oct 18, 2006 #7


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    Actually a brushless motor would make an AC alternator, whereas a brush type motor would make a DC generator. No idea whether that matters for this application or not (rectification may even be part of the project?).

    An AC motor would also have to meet one of these criteria to produce electricity:
    - Be a permanent magnet motor.
    - Retain sufficient residual magnetism.
    - Be connected to current to establish magnetism (or at least long enough to re-establish residual magnetism).

    moo (moo') adj. Of no practical importance; irrelevant, such as a moo point (i.e. a cow's opinion).
  9. Nov 7, 2006 #8
    Well IC engines start off from the size of .022 cc which is run on nitro methane. 1cc onwards engines are available for the petrol version. You can use anything bigger than this. but we need to know your design requirements to tell you any more stuff. YOu can also get very small generators. But why not use dynamos. They come in even smaller variants.
  10. Apr 10, 2007 #9
    Hello,I'm new on the forum.
    I have a similar question as idarab.I was wondering if you knew of a small dynamo(around the sise of a fist) that could produce the same amount of power as a 1500 mAh,7.2V DC 6-cell NiCd battery when hooked up to a small RC engine ( similar to this...http://www.lookthru.com/index.php?q=aHR0cDovL3d3dzIuZ3BtZC5jb20vaW1hZ2UvaC9ocGlnNTEwMS5qcGc=&hl=3ed )
    I want to convert my rc car(super clod buster kit) to run on a gasoline powered generator as the battery runs out too fast.
    All suggestions are appreciated.

    Last edited: Apr 11, 2007
  11. Apr 16, 2007 #10
    Kind of over engineering but...connect the nitro engine to a propulsion electric then wire it to the motor in the truck. Dumas makes a good 12v boat motor that should generate a few volts.

    But why not just switch it to direct glow fuel ....... or is this a "I wonder if I can" project?
  12. Apr 16, 2007 #11


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    That link doesn't work either.....

    I don't know how small you mean for a "small" RC engine, but I'd be surprised if there were any out there that would put out less than what you get from a 1500mAh NiCd pack in 10 minutes or so (typical for an rc car).

    The numbers you gave equate to 10.8 w-h or 64.8 watts for 10 min.

    Gas (nitromethane) rc engines don't get much smaller than 1/4 horsepower, which is 186 watts. And that's output, whereas the battery is input power.

    Last edited by a moderator: Apr 22, 2017
  13. Apr 16, 2007 #12


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    I don't know what the HP rating for one would be, but Cox's old .049 has to be less than a 1/4 HP. I'll have to do some looking around.

    EDIT: I actually found a set of power curves for the .049s. They maxed out at about 60 W:
    Last edited: Apr 16, 2007
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