Aboutcleggsan Expertise All technical areas of Electronics Engineering.
Experience BSEE, MBA, Design, R&D, University Research.
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Organizations IEEE, Consumer Electronics Society, Audio Engineering Society.
Broad teaching experience; work experience mostly in consumer electronics and conversion from analog to digital technologies. Pioneer in digital audio at all levels.
Expert: cleggsan Date: 5/5/2008 Subject: DC Generator with low rpm, high power output.
Question I am interested in doing a small experiment, where a DC Generator, rotates at 1-10 rpm, and generates in the vicinity of 9-12 V, 1-5 A, based on rpm, with high efficiency(minimal frictional losses), and low gear ratio(1:10 max). Is such a generator possible? I am based in NJ, USA, and can would also be interested in some lab/test facility where such a generator is available for testing. Please feel free to contact me on how this can be pursued further.
Answer Power of 12v @ 5a is 60w.
60w = 0.08 hp
From above it is very realizable and could be rather easily prototyped. The generator could be a small permanent magnet fractional horsepower motor used as the generator.
It would require some effort to select the right components, of course. The speed you are discussing is very slow so you may end up having to use a motor/generator of larger size in order to get out the power that you want at such a slow speed. If your gearbox cannot be more than 1/10 speed reduction it means you are limited to 100 rpm rotational speed of the generator shaft. Most permanent magnet devices run at much higher speeds to get their full, rated operating conditions.
A custom wound generator may be what you need.
I don't know if this is a "hobby" level project or serious, hire for pay situation, but my suggestion might be to start at a college group; NJIT for example, and cozy up with a lab instructor or professor and let them fashion a student project out of it. They could take it to the feasibility level and make up a working prototype easily, I think.
Also, CCM (County College of Morris) has a good program that might be interested in a student project of this type.
There are many testing and laboratory services based in NJ but I did not find one that specialized in small motors and generators; however, any good electrical testing group could do this as it is not rocket science. The downside would be cost; most testing labs are very expensive due to their heavy burden of complying with government, professional and international standards of one kind or another.
