> On Feb 28, 2017, at 9:54 AM, Corbin Dunn via EV <[email protected]> wrote: > > >> Il giorno 27 feb 2017, alle ore 4:22 PM, ROBERT via EV <[email protected]> >> ha scritto: >> >> I noticed a series of e-mails on regen and smart cruise control. These two >> topic are closely related. I have been looking at implementing regen on an >> AC motor controller. I found that designing an AC motor controller in >> simple comparison to selecting the best regen implementation. There are two >> typical methods for regen. If you release the accelerator then start regen. >> If you depress the brake then start regen. Tesla and Nissan use the first >> method. > > Tesla uses a different method; you must partially depress the throttle pedal > to coast (zero power and zero regen). Regenerative braking gets progressively > stronger as you lighten up off the pedal. It does full regen when your foot > is off the pedal.
The Chevy BoltEV is similar. There is an instrumentation icon that shows power in KW (0 - 150). It is green for regen and amber for drive. Pressing the accelerator pedal further increases drive power, while easing off the pedal reduces drive power eventually to zero KW, then begins increasing regen power. It is possible to feather the pedal to make power zero and coast. Removing the driver's foot completely from the accelerator pedal will bring the car smoothly to a complete stop. There is also a steering wheel mounted switch that increases regen power and brings the car to a more aggressive stop. I haven't used the brake pedal more than a few times in about 1000 miles of driving, but I have not noticed any effect on regen. That might be because I was not looking at the instrumentation when using the brake pedal. > >> Some other companies use the brake depress method. The main advantages of >> the release accelerator method is fewer components and it is simpler. The >> disadvantage is with cruise control and down hill and then up hill. For in >> town cruise control, it works OK. The brake depress method solves the down >> hill/up hill problem; however, you do not get as much regen capacity because >> at some point the mechanical brake must be enabled. Added to the >> complication is the sequence of firing or not firing of the IGBTs. There >> are numer >> ous technical articles is the SAE journals and electrical journals proposing >> IGBT firing sequences that produce better regen. All manufactures are >> trying to extend the range of their vehicles. At present, improvements in >> inverter and component design provide less than a percent or two of >> efficiency improvement. Regen is a hot topic because a good regen >> implementation could add 10 plus percent in range. At present, recoverable >> energy from regen in 20 - 30 %. A smart system that could use GPS data, >> road map data, traffic light data and AI programming could recover a huge >> amount of energy. If you check current technical literature, you find that >> car manufacturers are working on this type of system. I am interested in is >> what current EV do? Is fully charging a battery not allowed so that regen >> can always happen? > > In a Tesla, it isn’t prevented. In the BoltEV, regen is limited when the batteries are fully charged and/or too cold/hot. It has a charging limit called hilltop reserve that only charges to 90% of capacity to allow regen directly after charging. > >> Is regen modified when the brake paddle is depressed? > > In a Tesla, it isn’t modified when the brake pedal is pressed. It is purely > with the throttle pedal. As I said above, I think there is no effect on regen due to brake pedal depression. There is a steering wheel mounted switch to increase regen. > >> Under what situations is regen disabled? > > Regan is disabled, or the max regen amount is limited, when the battery is > fully charged or cold. The BoltEV is similar. > >> Do all EV have a regen disabled light? > > All EV’s don’t. The regen icon that spins during regen appears gray when regen is not available or limited. > >> Do all EV have a regen d >> isable switch? > > No - the Tesla does not have a switch to disable regen. Hybrids, like the > Prius also do not have the ability. Neither does the BoltEV. > > corbin Ed > >> Which EVs only use release of accelerator method? Does regen adaptive based >> on similar trips? The questions are numerous. >> >> -------------- next part -------------- >> An HTML attachment was scrubbed... >> URL: >> <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20170228/15bbb0e2/attachment.htm> >> _______________________________________________ >> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >> http://lists.evdl.org/listinfo.cgi/ev-evdl.org >> Read EVAngel's EV News at http://evdl.org/evln/ >> Please discuss EV drag racing at 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 > Read EVAngel's EV News at http://evdl.org/evln/ > Please discuss EV drag racing at 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 Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
