> My understanding is that these are _very_ inefficient as motors, let > alone as alternators. Common stator laminations are fairly thick, the > rotors don't have any laminations, so there are significant eddy > losses. > There is a reason these come fitted with a fan, which is another loss > itself. I have thought a new permanent magnet or laminated rotor might > be worth a try. But one would need to measure temperature and > efficiency > with realistic loads to see if they would be practical.
They are quite inefficient as alternators, probably also as motors. Also they are not strictly brushless. There are two brushes to get current to the rotor. The reason the rotor is not laminated is the magnetic flux there is quite constant and certainly is not reversing. The rotor is magnetised with a fairly high current like 3A at 12V. Changing this current is the way output voltage from the alternator is controlled. This rotor current is a pure loss. IMHO it is today better for our purposes to magnetise the rotor with supermagnets. ------------------------------------------------------------------------------ Special Offer-- Download ArcSight Logger for FREE (a $49 USD value)! Finally, a world-class log management solution at an even better price-free! Download using promo code Free_Logger_4_Dev2Dev. Offer expires February 28th, so secure your free ArcSight Logger TODAY! http://p.sf.net/sfu/arcsight-sfd2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
