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PMAC vs induction motor for model 3

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Realistically speaking the rwd and awd are ABSOLUTELY THE SAME on regen capacity, since the grip is based on the discharge power of the battery wich is far lower than the capacity of the battery to charge.

I'm not sure what this is supposed to mean, I think you were making the point that regen capability is limited more by the pack's ability to accept the resulting charge, and not necessarily by tire traction. Nonetheless, to clarify:

1) Grip is based traction of the tires. (It is likely, however, that the braking forces regen can exert based on the amount of energy the inverter/pack can handle is less than that needed to break tire traction)

2) As regen generates energy that is accepted by the battery, it's the charge rate the battery can accept that factors in to this. (not discharge)

3) The discharge rate of the battery is higher than the charge rate. (not lower)

It's a common misconception based on the fact that the brake are more strong on the awd due to grip factor, but in reality the regen is like a soft brake not a "full power brake"

The stronger AWD regen is likely due to a second drive unit that's able to take advantage of the rotational forces at a given speed.

(edit: I realize the poster's language was not English, my response is not intended to be critical)
 
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I'm not sure what this is supposed to mean, I think you were making the point that regen capability is limited more by the pack's ability to accept the resulting charge, and not necessarily by tire traction.
exactly
you can discharge faster than you can charge.
so you can have sub 6 sec acc, but you can't have sub 6 sec dec ( without brakes ), realistically you can have sub 18? 24? i don't know the exact numbers but it doesn't matter, the real force applied on the tires is during the acceleration phase, not during regen, so your tires won't slip from the sloppy dec forced by the regenerative force.

2) As regen generates energy that is accepted by the battery, it's the charge rate the battery can accept that factors in to this. (not discharge)

3) The discharge rate of the battery is higher than the charge rate. (not lower)
yes, exactly!
Sorry i've miswrote but this is what i meant
 
It would be interesting to test. Seems the current cap is about .3 g's of decel from regen.

That's nothing to sneeze at, and can easily exceed the grip of LRR tires in less than favorable conditions, especially when cornering.
 
Informative, but I would like to see the graph scaled to zero on the vertical axis for better perspective on proportional differences among the vehicles.

I was thinking about this too since it is a pet peeve of mine. Thanks for the nudge

upload_2017-9-4_10-25-12.png
 
The Prime doesn't belong in that list since it's normally a gas powered car. It needs the gas engine to achieve sub 12 second 0-60 mph times. ie - 79% of all trips require a the gasoline engine to run. This is higher than 45% for the CMax and Fusion PHEV and on a far lower tech level than the 11% that a Volt needs gasoline power.

https://www.arb.ca.gov/msprog/acc/mtr/appendix_h.pdf see Fig 7, yellow bars to the right.

The Prius referenced in this document is the original, Gen1 Prius Plug-in, not the Prius Prime (2017). The Prius Prime can do 0-60 in all electric and has a range similar to the Ford PHEVs (about 25-30). And Toyota listened to Gen1 owners and allowed the Prime to drive in all electric, like the Volt, until the battery is "depleted", never forcing the engine on if the driver so chooses.
 
Is this article not accurate?

The Electrek Review: 2017 Prius Prime – This is not the EV you’re looking for

Excerpt:

Don’t get me wrong – you can, if you really try, get 10 or so miles out of a Prius Plug-in just like you can get 20 or so out of a Prius Prime – if you do everything right and you live in 70 degree weather. Just don’t turn on the heat/AC, radio, windshield wipers, try to accelerate too fast or – get this – try to regen too much electricity going down a hill. All of these things turn the ICE engine on and keep it on for 5-10 minutes regardless of how much battery you have and what roads you are on.
 
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The Prius referenced in this document is the original, Gen1 Prius Plug-in, not the Prius Prime (2017). The Prius Prime can do 0-60 in all electric and has a range similar to the Ford PHEVs (about 25-30). And Toyota listened to Gen1 owners and allowed the Prime to drive in all electric, like the Volt, until the battery is "depleted", never forcing the engine on if the driver so chooses.

The Prime's 0-60 is over 12 seconds in EV mode. If you have passengers, or need full rated power, or encounter hills, you will have to burn gas. This gives a huge EV 'paper' advantage over the other cars, but not in actual use.

This is like comparing a Volt hypermiling to a Prime. New Volts go easily over 60 miles AER at 60 mph (70.4 mi on an actual freeway round trip), but never have to use gas to climb hills when any battery is left.
 
So if the regen limit is due to the rate at which the inverter can put energy back into the battery.. does that mean that an appropriately sized supercap and a way of shunting that energy into the super cap would enable more capture of regen energy?

Yes, that's kinda what KERS systems do. The regen rate is not limited by lithium charging. It does require extra hardware hauled around all the time. It makes great sense on the track.... Not sure where the tradeoff is for street use.
 
It looks like Seth (the reviewer) was doing it wrong. That's understandable too, since it's a new car to him, but the heat pump/AC should be capable of defrosting the windows to around 20F as long as there aren't too many people in the car.

Front Defroster - EV mode

Edit - Even the 1st gen Volt, which has ~1.5x the EV range of the Prime has ERDTT, which insideevs complained about. A fast defroster for a PHEV will likely fall back to the engine because it's really good at providing heat instead of using a larger/more powerful heater/heat pump like you would see in an EV.

Op-Ed: Where the 2016 Chevrolet Volt Falls Short
 
It makes great sense on the track.... Not sure where the tradeoff is for street use.
You will use this little 'extra' energy in about a couple of seconds, it will get you very very little in gained range since it will only be used when you exeed the generous regen ability of the car ( wich of course in a race it's an every-brake situation, but in the street use it's about an emergency brake or similar ), at the cost of extra hardware.. a bad bargain.
And if you really need to stop so fast, it's better to use the brake.. at least you put the rust off if you use them once in a while :D
 
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Yeah, with the switch to PMAC and the car being much lighter, the Model 3 is going to share a lot more similarities with other existing EVs (including being more efficient in the city).

However, the relative efficiency still matters. here's how the 3 compares to the most efficient EVs in the market:
Combined / City / Highway
Ioniq Electric: 136 / 150 / 122
Model 3 (LR): 126 / 131 / 120
i3 (60 Ah): 124 / 137 / 111
Bolt: 119 / 128 / 110
Spark EV: 119 / 128 /109
e-Golf: 119 / 126 / 111
i3 (94 Ah): 118 / 129 / 106
Leaf (24 kWh): 114 / 126 / 101
Leaf (30 kWh): 112 / 124 / 101
i-MiEV: 112 / 121 / 102
fortwo electric coupe: 108 / 124 / 94
Focus Electric: 107 / 118 / 96
Soul Electric: 105 / 120 / 92
Model S 90D: 104 / 102 / 107

I think this bodes well for highway efficiency, since the trajectory is that it looks like it's likely to beat the Ioniq at more realistic highway speeds (given how much higher the city rating is, the Ioniq is likely far more city optimized than the Tesla).


to me, all of those cars look like they were beaten with an ugly stick!

the model 3 is the only pure electric car I think that looks great for any car and not just an electric.And and the enhanced range and supercharged networks are just a bonus I would buy the model 3 without either of those.