Thanks, Lee, it looks like some solutions could be designed into a controller, but are lacking in a Kelly or Curtis sepex offering.
Can you please help with the quote from below. If there is more inductance in the large motor, and the time constant is L/R, and the resistance goes down, it seems like the time constant gets bigger even faster with the bigger motor. ----- Original Message ----- From: Lee Hart Sent: 08/17/13 11:05 AM To: Electric Vehicle Discussion List Subject: Re: [EVDL] S.E.P.X . controller for 500V , 450Amp Motor The L/R time constant will be slower, but not *that* much slower. First, because the lower inductance of the big motor is compensated for by a lower resistance as well. So it very well may not be much different than a smaller motor. Second, because the inductance of a motor is a side effect of its design. We really don't know here if this was *designed* as a high-inductance motor or not. I'm not an expert in the area of motor design, so perhaps someone who is can help here. But what I notice is that if you have two motors of the same type and roughly equal horsepower, the heavier motor (the one with more iron in it) tends to have more inductance. I think it's a bit like transformers; you can make a light less-efficient one that runs hot, or a heavy more-efficient one that runs cooler. The latter has more iron, and so more inductance as a consequence. ... -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20130818/b773b271/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)
