http://en.wikipedia.org/wiki/Selsyn
Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: [email protected] Private: http://www.cvandewater.com Skype: cor_van_de_water XoIP: +31877841130 Tel: +1 408 383 7626 Tel: +91 (040)23117400 x203 -----Original Message----- From: [email protected] on behalf of Ds2inc Sent: Sun 2/10/2013 8:08 AM To: Electric Vehicle Discussion List Subject: Re: [EVDL] Series and parallel switching I don't really understand this principal and can't find much reference to it could you explain in more detail if possible please as tho is all new learning for me! Thanks so much!! Sent from my iPhone On Feb 8, 2013, at 5:22 PM, Jeffrey Jenkins <[email protected]> wrote: Lee Hart wrote > ... > If you run PM motors in parallel, their voltage is the same, and they > both run at the same speed. They behave like a limited-slip or locking > differential. Nice in snow or on a drag strip; but it leads to extra > losses in normal driving. Going around a curve, the outside motor is > forced to turn faster, so it becomes a generator, and is actually > dragging the wheel backward (negative torque). The current it generates > drives the inside motor harder, trying to make it turn faster... It perhaps should be emphasized a bit more strongly that PM motors should not be connected in parallel because there will be always be some current circulating between them depending on the RPM/Volt (Kv) ratio of each motor, the total resistance of the motor interconnection loop and the difference in RPM (if the shafts aren't locked together). The magnitude of the circulating current can be surprisingly high, and effectively amounts to unequal sharing of the load between the two motors. TL;DR version: don't parallel PM DC motors. -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/Series-and-parallel-switching-tp4661043p4661139.html Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com. _______________________________________________ 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) _______________________________________________ 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) _______________________________________________ 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)
