View Full Version : How many electric motors???
SD3_Driver 07-05-2012, 06:58 PM How many electric motors does the FFH has???? Besides the traction motor, is there another one???? I've seen people talking about two electric motor but I have not seen any "official" word on this. Also why the charge arrow turns green when under heavy regen??? Looks like it charges a bit faster than normal when green.:confused:
Right Lane Cruiser 07-06-2012, 11:45 AM Hi, SD3 -- it has two main motors arranged in a similar configuration to that found in the Prius. There is a "traction" motor and a "generator" motor. Both are multiplexed with engine input through a planetary gearset which is often labeled an "ECVT" though it bears no relation at all to mechanical CVTs such as the ones in Hondas and is more properly known as a powersplit device. The site below will help you understand how the system works:
http://eahart.com/prius/psd/
The regen level is tuned to mimic engine braking with no pressure on either pedal but will ramp up when the brake pedal is used in proportion to pressure applied. The coloration is just there to indicate visually how much regeneration you are using.
The regen level is tuned to mimic engine braking with no pressure on either pedal.
Why to they insist on doing this? I've been gliding in N in MT cars my whole life. That is how my daddy done taught me to do it. It just feels right. Now I am in and AT that can glide in N and all you crazies convinced me to pump my tires up to 50 PSI and if feels great to just roll and roll and roll.
In a car totally designed around efficiency, why kill efficiency with regen braking when it is not being called for? Right pedal is (+) momentum, middle pedal is for (-) momentum and no pedal means let it roll . . . . its not that hard, people!
Right Lane Cruiser 07-06-2012, 12:48 PM I'm entirely on your side of the fence, Chris. There is a dead band that isn't too hard to hit in the FFH with a little bit of pressure on the accelerator, but I shouldn't have to futz with it.
I'm even more frustrated with the LEAF -- that one has almost no dead band at all and requires very close attention to the gauges to achieve zero energy consumption/generation glides. For longer glides and bumpy roads I have to put it into neutral -- which requires holding the shift "puck" in the N position for 2s (pretty much the same as the way the Prius shifter works).
Is it true that the cycle of regen braking back to forward momentum is only about 20% efficient with all of the inversions and losses?
RedylC94 07-06-2012, 01:56 PM Why to they insist on doing this? ... In a car totally designed around efficiency, why kill efficiency with regen braking when it is not being called for? Right pedal is (+) ... , middle pedal is for (-) ... and no pedal means let it roll . . . .
I agree. It's probably a concession to help avoid confusing stupid people who are accustomed to a bit of "engine braking," and to encourage them to regenerate gently in circumstances when they should be doing so.
Would it be possible to circumvent the default regeneration feature by making a hand-operated contraption to mechanically hold the accelerator at the magic freewheeling angle when one's foot is removed? A software solution would be far preferable and less clumsy, but probably isn't allowed.
I agree. It's probably a concession to help avoid confusing stupid people who are accustomed to a bit of "engine braking," and to encourage them to regenerate gently in circumstances when they should be doing so.
Most of these cars come with a couple of different driving profiles, ECO, Sport, etc. All we need is a HMer option. Or if you like, the "non-stupid" option. :D
I'm even more frustrated with the LEAF .. For longer glides and bumpy roads I have to put it into neutral -- which requires holding the shift "puck" in the N position for 2s (pretty much the same as the way the Prius shifter works).
If the Leaf is moving you can blip it into reverse, it shifts instantly into neutral.. it may beep at you.
I wish they did all these electrics with pushbuttons on the dash to select the "gears". The PIP has a dash gear lever I believe.
SD3_Driver 07-06-2012, 05:19 PM Nice RLC, now I understand... I was looking under the hood ( with a friend), and was able to see what looks like an electric motor and what should be the PSD, but I was not able to explain or find where the second motor was, so it confused me a bit.....
08EscapeHybrid 07-06-2012, 05:29 PM Plain & simple, its programmed to mimic the operation of conventional vehicles. That's why it mildly regens when you take your foot off the accelerator, and under 6 MPH it will creep forward when you release your foot from the brake as a normal vehicle with an automatic will. Otherwise, if they didn't make it mimic the operation of normal vehicles as much as possible, they may open themselves up to liability.
lolder 07-07-2012, 05:32 PM Is it true that the cycle of regen braking back to forward momentum is only about 20% efficient with all of the inversions and losses?
The regen cycle or EV cycle is about 70% efficient. You can pulse and glide below 47 mph. by avoiding HVB charge and discharge arrows with careful go pedal modulation and improve low speed mpg. about 30 %. It's not hard to do but try it out with no traffic.
NeilBlanchard 07-07-2012, 08:55 PM Ideally, in Eco mode all EV's should free-wheel coast when you lift your right foot off the accelerator pedal. It should be easy, and this would encourage coasting, and you learn to minimize how much acceleration you do. Put ALL of the regeneration on the *brake* pedal; you know the one for stopping. ;)
An added benefit would be the ability to rest / stretch your right leg on longer drives. Lift you foot to coast, and relax all the muscles -- much better than having to concentrate on some dial to find the perfect position...
The Honda Fit EV apparently does this in the Eco mode -- the Leaf and the i MiEV (and the Focus? and the Mini E) designers should all learn from those of us who have been practicing ecodriving aka hypermiling!
08EscapeHybrid 07-07-2012, 10:12 PM The Honda Fit EV apparently does this in the Eco mode -- the Leaf and the i MiEV (and the Focus? and the Mini E) designers should all learn from those of us who have been practicing ecodriving aka hypermiling!
The problem is that vehicles are designed for the masses. Hypermilers are in the minority.
lolder 07-08-2012, 06:02 AM Another thought is that with no built in regen drag, you would have to be constantly moving your foot between the go and stop pedals. These vehicles gain speed very quickly coasting down very slight hills. There's no difference in efficiency between the built in regen and braking regen. The way they are presently designed, in mild terrain, you can do most speed regulation with one pedal.
08EscapeHybrid 07-08-2012, 10:26 AM In my FEH I find that even with the automatic mild regen, that its fairly easy to exceed the speed limit going down hills, even when I have the cruise set 10 MPH under the limit.
Right Lane Cruiser 07-08-2012, 07:10 PM If the Leaf is moving you can blip it into reverse, it shifts instantly into neutral.. it may beep at you.
Interesting. I had assumed that the vehicle had a safety built into it for such use but wasn't willing to try it out to see what happened. Still not sure I want to try it. :p
Fortunately, I'm rather experienced at anticipatory driving and the 2s hasn't been too much of an issue. ;)
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