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Dual motor efficiency
- Thread starter LectrikPower
- Start date
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- Model 3
At the reveal, Elon said they were able to shrink the car by moving the driver forward (since there is no engine). I'm not sure if this means you'll sit closer to the windshield or what, but it does explain why there appears to be unused frunk space. It's for your legs now! And that means it's unlikely the frunk can be extended back toward the driver.That's certainly the case with the S/X, but not a given with the 3. They may opt to have a single frunk size and leave the RWD cars with unused volume between the axles.
Having said that, it does look like the frunk could expand rearward based on this picture.
Is Tesla under-utilizing regen, because it would be awkward to have full regen with Single Pedal Speed Control?
In a RWD, full regen on throttle lift, would be the equivalent of Drift Mode.
Is the article right that, the Tesla brake pedal is friction only?
I would find that dissapointing, as I really like blended braking (as per the Volt).
I hope these things are software setting choices.
In a RWD, full regen on throttle lift, would be the equivalent of Drift Mode.
Is the article right that, the Tesla brake pedal is friction only?
I would find that dissapointing, as I really like blended braking (as per the Volt).
I hope these things are software setting choices.
garsh
Re Member
The amount of regen is controllable via an option. I know the S allows a lot more regen than a Nissan Leaf. Sorry, I don't know where a Volt lies in that range.
That's my understanding.
The Leaf also has blended braking. I think this is a mistake. It's a more complicated system. It also means that the brake pedal feel differs depending on the amount of regen available (ex - charged to 100%, and there is NO regen available).
I think Tesla made the correct choice here - offer a relatively high amount of off-pedal regen, and have the brake pedal control only the friction brakes.
I wouldn't say they're under-utilizing regen. Remember "full regen" is pretty light compared to aggressive use of friction brakes. Lifting the throttle going into a turn hot would induce oversteer, if the traction/stability nannies didn't intervene. "Coasting" (no accel/decel from the motor) requires partial throttle pedal, like when an ICE car is reving high and you want to avoid engine braking.
The S/X brake pedal is friction only, which I expect they'll carry over to the 3. I dislike blended brakes and am hopeful they keep them separate.
Dan Detweiler
Active Member
I have driven a Volt for four years and that was the first thing I noticed about the Model S when I drove it. There is a lot more regen braking in the Tesla than with my Volt.
Dan
dgpcolorado
high altitude member
My general impression is that you are overthinking these things. Tesla has fairly strong regen — yes, even with "just" RWD — that allows for single pedal driving. On a typical trip, the only thing I use the brake pedal for is to start the car and to hold it stationary at a stop light. Otherwise all of my accelerating or slowing is done with the "go pedal", even brief stops at stop signs unless I have to wait for traffic.
Unless the battery is quite cold or nearly full, and regen is limited, the Tesla regen is strong enough to slow the car to nearly a stop when going down a steep hill (which is much of my driving here). The friends who have driven my car area amazed by this.
Single pedal driving is quite intuitive in my experience and one rapidly becomes accustomed to it. After which, going back to any sort of regular car seems like a major step backwards. Having driven a LEAF for years I definitely do NOT want to go back to blended regen on the brake pedal; I'll stick with single pedal driving.
You really need to take a test drive in a Model S and your concerns will be alleviated.
Volt does have a Low Mode which is similar to single pedal speed control (like Tesla), but I guess it's less agressive on regen.
Volt has added paddles to increase regen on-demand.
However, neither is needed, because the brake pedal engages regen.
It works real well and is completely smooth.
The -kW reading confirms regen is happening vs friction braking.
Volt has added paddles to increase regen on-demand.
However, neither is needed, because the brake pedal engages regen.
It works real well and is completely smooth.
The -kW reading confirms regen is happening vs friction braking.
There are some mixed impressions on Tesla Regen.
One impression was that it's not strong enough to justify having it on the front wheels [AWD].
Another is that Tesla regen is beyond what any other EV offers.
I gather that Teslas lift throttle regen is more than adequate for normal driving.
However, I suspect it is dialed back, to keep it safe.
I cant believe people could handle 100% regen on throttle lift.
Thats why, I would like to see regen on the brake pedal, as its easier to modulate the full range of regen that way.
One impression was that it's not strong enough to justify having it on the front wheels [AWD].
Another is that Tesla regen is beyond what any other EV offers.
I gather that Teslas lift throttle regen is more than adequate for normal driving.
However, I suspect it is dialed back, to keep it safe.
I cant believe people could handle 100% regen on throttle lift.
Thats why, I would like to see regen on the brake pedal, as its easier to modulate the full range of regen that way.
dgpcolorado
high altitude member
This simply isn't true. Tesla regen is modulated just fine on the accelerator pedal and is speed dependent, just as one would expect. Enough regen to slow the car to a stop going down a 14% grade isn't enough for you?
But until you actually try the Tesla version of regen there isn't much more I can say. Don't knock it until you try it.
JeffK
Well-Known Member
As a prius owner I say regen integrated into the brake pedal stinks... the hand off to the physical brakes is clunky, it's more complex to manufacture, in a Prius there's a messed up acceleration feeling when braking over a bump and the car jumps forward a few ft (read: dangerous).
With regen in the accelerator you can do one pedal driving which is super convenient.
With regen in the accelerator you can do one pedal driving which is super convenient.
I think there is some confusion about dual motors being more efficient than single. The single motor Model S has the large motor and drive unit that was originally developed. Later, Tesla designed the smaller and slightly more efficient front motor and inverter unit. It's not different gearing. It is just that the newer, smaller motor is a little more efficient.
Dual motor Model S have the small motor both in the front and in the back. The PXXD versions have the old large motor in the back and the smaller newer in the front. The PXXD can switch off the back motor when cruising and running just on the smaller motor. They call that torque sleep.
It's not gearing that makes it different, it is not running two motors instead of one. It's just the more efficient smaller motor that makes the difference. In general, the type of electric motor Tesla is using runs more efficient at higher load than partial load. Having two smaller motors has the advantage that you can accelerate fast and efficient using both motors at high load, and when cruising, you switch one motor off so the load on the other is higher making it more efficient.
Dual motor Model S have the small motor both in the front and in the back. The PXXD versions have the old large motor in the back and the smaller newer in the front. The PXXD can switch off the back motor when cruising and running just on the smaller motor. They call that torque sleep.
It's not gearing that makes it different, it is not running two motors instead of one. It's just the more efficient smaller motor that makes the difference. In general, the type of electric motor Tesla is using runs more efficient at higher load than partial load. Having two smaller motors has the advantage that you can accelerate fast and efficient using both motors at high load, and when cruising, you switch one motor off so the load on the other is higher making it more efficient.
That makes me hopeful the cost to go to all wheel drive may not be too much. Two smaller motors, that don't need to be nearly as capable as higher powered ones, might not be too much more expensive. I would like all wheel drive but it'll be a lower priority for me. There are times it's helpful and a little added range from more regen is always welcome.
JeffK
Well-Known Member
Speaking of two motors... What about 4 motors at some point? You could then get more individual wheel control, right? Wouldn't that allow for better handling and even turning? (If you weren't concerned about the rubber on your tires, you could turn the car 360 degrees without actually turning a wheel.)
AZ Desert Driver
Rare combination
I agreed Tesla Single Pedal Regen is effectively enough (even if it's softened up).
My question remains, is it 100%?
Can the Tesla gurus to enlighten me as to the % of Regen Tesla achieves?
How can regen be anywhere near 100% w/o use of Regen on Front Wheels [AWD]?
Does stability control kick-in and engage front friction (to balance 100% RWD Regen)?
Just because Prius mucked up blended braking, does not mean it stinks.
If Volt can do blended braking perfectly, Tesla could too.
My question remains, is it 100%?
Can the Tesla gurus to enlighten me as to the % of Regen Tesla achieves?
How can regen be anywhere near 100% w/o use of Regen on Front Wheels [AWD]?
Does stability control kick-in and engage front friction (to balance 100% RWD Regen)?
Just because Prius mucked up blended braking, does not mean it stinks.
If Volt can do blended braking perfectly, Tesla could too.
100% of what? Regardless of anything else, max regen power will always be a fraction of max acceleration power, because batteries cannot absorb power nearly as quickly as they can supply it.
