How about a one way clutch on each motors output shaft? Similar to my EV Warrior dual bike motor setup, except one on each motor. Dach.
________________________________ From: Lee Hart <[email protected]> To: Electric Vehicle Discussion List <[email protected]> Sent: Thursday, February 7, 2013 7:06 PM Subject: Re: [EVDL] Series and parallel switching On 2/7/2013 7:09 PM, Cor van de Water wrote: > Great way to make an electric LSD (Limited Slip Diff) > Practically, I fail to see any significant issues. The only issue is when turning a corner on normal dry pavement. The outside wheel has to rotate faster than the inner wheel. The inner wheel has to produce all the "motoring" torque, and the outer wheel becomes a brake, trying to hold the vehicle back. The sharper you turn, and the faster you go, the worse this effect becomes. As for how "bad" the extra loss is, that will depend on how efficient the motors are. This is a case where the worse the motor's efficiency is, the less of a problem this will be. If a car's wheels are 5 feet apart, and it has a 30-foot turning circle, then the inner wheel has a 27.5-foot circle and the outer wheel a 32.5-foot circle. That's a 18% difference in wheel speeds. This is probably tolerable with 80% efficient motors, whose speed difference could be 20% between full load and no load. But it could make 90% efficient motors really fight! If this turned out to be a problem, you could simply force the motors to be in series during sharp turns. Save parallel operation for high speeds where you should never be turning sharp anyway. -- A designer knows he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away. -- Antoine de Saint Exupery -- Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20130207/56819ccb/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
