Model 3 Highland Performance/Plaid Speculation [Car announced 04.23.2024]

[Sweed269]

Motor speed is important.
Plaid has a much bigger battery and possibly a more optimized for performance chemistry.

 

[mpgxsvcd]

We went through all of this about 30 pages ago, and this is much more complicated than this.

Ask yourself- as humans, we know how to build a 1V motor, a 10V motor, a 100V motor, and a 1000V motor. So there is nothing special about the Model 3's 320V motor. If there were no trade offs, why didn't Tesla just build a 280V motor if they had a battery that was 288V when at 0% SoC? Why is the only solution a higher voltage battery?

Or, if there were no tradeoffs, why did the original Model 3 engineers arrange the 4,416 cells in a 96s configuration, instead of a 110s like the Model S?

And then if voltage was the only question, think about the performance we could be getting out of the 800V cars. Or I guess the motors would instantly fail because they are all 320V motors and we don't know how to build otherwise?

The Plaid achieves it's feat of not degrading over discharge not simply because of higher initial battery voltage. It uses a different magnetic laminate design internal to the motor as well as carbon overwrapping to minimize the rotor-stator gap, which lowers the back EMF of the motor. This is primarily there for one reason- which is so it can maintain flat power up to about 18,000 RPM. Previous designs fall off in power as the RPM increases because the back EMF means that the voltage differential between the motor and batteries fall as RPM builds, and this causes the current to decrease, leading to an overall power decrease.

But this flat rating means something else- the Plaid's motor is also just less sensitive to voltage, so it doesn't care that much as SoC decreases either. In a lot of ways there isn't a difference betweem 20% SoC and 50% RPM because they both represent a change in voltage differential.

Also, there's a good chance the Plaid motor is underrated and limited in software. If you make a 500HP motor (remember, 3 of them), and then limit it to 350HP in software, the car can handle a lot of voltage drop without running into a physical limit.

This is a great post. So concise and easy to read.

 

[mpgxsvcd]

Controllers cannot make up for the inherent back EMF in a motor, and the Plaid uses the identical controller as a Model 3 yet achieves a much flatter power output vs voltage because the magnetic machine is different.

And this has nothing to do with "battery size"- The Model 3 today already draws peak power from the battery at about 45 MPH, and falls off after that, and there's no reason that the battery cares how fast the car is going, so it could do that 45 MPH power all the way to 150.

Also, Plaid has more range than a Model 3 AND more power, and flat power. 7C discharge isn't really anything nowadays, and easilly gets you Plaid-like acceleration without giving up range. This is not a hybrid performance car that needs a tiny battery with 5 miles of range that needs to do 60C charge and discharge.

In all of my runs peak battery power occurs at 55 mph. 448 KW is the most I have seen it report coming from the battery.

 

[AAKEE]

That not how it works

Yes it is.

The voltage will always drop the same percentage regardless of where you start.

It does not. The voltage droop depends on the internal resistance, wich is not the same over the SOC band. The internal resistance is also very depending on the temperature.

The issue is that a motor will need a specific voltage to produce a specific power. It is the voltage that is the ”motor” for making high currents.

The resting voltage from a battery pack reduces with reducing SOC.
It also droops more the higher the load.

The motors in the model 3 P needs a high SOC from the Panasonic packs to deliver full power, ~ 70% or more. Of course battery temp dependent. So the battery is the liniting factor except with high SOC

The M3P has been sold in europe with the LG M-50 NMC(A) battery cells.
This battery can not deliver the same power and the battery is the limiting factor for power in all cases except about 80-85% with a heated pack. With this pack, the car is almost always power limited by the battery pack.

The Plaid I got after selling my M3P has a 110S pack instead of the standard 96S.
This gives a overhead for the voltage so the car can deliver power also at low SOC.
It produces virtually the same performance down to 20% SOC with a warm battery.
The plaid has the M3P motors but modified to resist higher rpm.

You need a controller that can take the increased amperage at the lower voltage to compensate for the percentage drop.

The voltage is always the driving force to create current.
It is impossible to create a current flow without use of the voltage as the driving force.
If the voltage is too low to create the needed combination of voltage/current, the current will be lower, and the power also will be lower.

Basically, every EV will loose power unless you limit its true max to a set value it can maintain at minimum.

Either the max rated or max allowed motor power or the battery will set the limit.

On the MSP the battery is not the limiting factor above about 20% SOC with a warmed battery.

The 3P was never designed as a sports car and has no artificial limits on top end power. It follows the voltage curve drop off at max amps.

…which reduces the power output.

Increasing the battery voltage so it still delivers the ”full power voltage” at full Power regardless of SOC will make the car deliver full power at all SOC.

 

[AAKEE]

But the Voltage increases gradually after it hits max current. Current is what decreases after the max. Voltage from the battery increases slightly.
View attachment 1010398

The voltage decreases about proportionally to the load (power).
The car is torque limited to about 50mph/80kph, and the power output increases propartionally to the speed, up to that points.
The battery voltage increases above the top power, as voltage droop is power output dependant. Reducing power putput teduces the voltage droop.

 

[gearchruncher]

The plaid has the M3P motors but modified to resist higher rpm.

This is the key here that you don't understand. What do you mean by "resist higher RPM"?

What you mean is "maintain power at higher RPM." This is the back EMF I talked about. If you don't understand what back EMF is, and what causes it, there is no way you can understand how the current - voltage - power relationship works in a complicated system between the batteries, controllers, and motors.

Nobody is saying batterry voltage doesn't go down with SoC, or temperature, or load due to internal resistance. But the Plaid does not pull off a flat power output from 5000-18000 RPM just because the open circuit voltage of the pack is 50V (15%) higher.

 

[gearchruncher]

The car is torque limited to about 50mph/80kph, and the power output increases propartionally to the speed, up to that points.
The battery voltage increases above the top power, as voltage droop is power output dependant. Reducing power putput teduces the voltage droop.

You're soooo close. Why does the power reduce above 50 MPH? We know the battery can handle more total power, it did it at 50 MPH. What is preventing the system from just holding that power to 150 MPH even at 100% SoC?

 

[AAKEE]

You're soooo close. Why does the power reduce above 50 MPH? We know the battery can handle more total power, it did it at 50 MPH. What is preventing the system from just holding that power to 150 MPH even at 100% SoC?

The EMF back force is naturally reducing the torque at higher rpm. Thats a natural law around electric motors.

 

[AAKEE]

This is the key here that you don't understand. What do you mean by "resist higher RPM"?

No, carbon fiber windings to make them do > 20K rpm without falling apart.

 

[gearchruncher]

The EMF back force is naturally reducing the torque at higher rpm.

But it's not. It does not reduce torque.
Back EMF is creating a voltage that offsets the battery voltage. Think of it as if the motor becomes a battery. At 0 RPM, the motor's battery is 0V. So if I apply 100V to the motor, I get 100A.
But at 5000 RPM, the motor's battery is 50V. So now if I apply 100V, I only get 50A. So I have to apply 150V to maintain 100A.

The Back EMF requires more input voltage to maintain the same current.

But the ratio of back EMF to the RPM is not a fixed property on all motors. You can make motors with less back EMF, espeically with advanced control strategies and super novel laminate designs. And this is what the Plaid motor does. It has much less back EMF than simpler motors.

So at 10,000 RPM a Model 3 motor might have 150V of back EMF, the Plaid motor has 50V. And now with the exact same battery, I can put way more current into the Plaid motor.

 

[gearchruncher]

No, carbon fiber windings to make them do > 20K rpm without falling apart.

Common misconception since Elon likes to lie about this.

As I've proven before, at 200 MPH, Plaid's motors are running less RPM than a Model 3 at 162 MPH or an older Model S at 155 MPH:

lightweight wheels model 3 performance 0-60 testing

been following this thread for a while. thanks for all the people running their independent "tests." whether they are scientifically accurate or not, it's entertaining nonetheless and keeps the conversation going.

teslamotorsclub.com

Which makes perfect sense as well, as keeping the RPM down helps with reducing back EMF. If you can afford the current out of the battery, then you want to keep your motor RPM down.

 

[Sweed269]

If you look at the real motor power curve without restrictions it's a line all the way down. The motor is software limited until 50mph and then the total system power is physically limited.
Starting power = software limit
Peak power = controller and battery max amps
high speed power = motor
Sustained power = thermal limits

Battery state of charge/temperature will effect max amps draw and voltage sag. This can limit peak, high speed, sustained and to a small degree starting.

 

[AAKEE]

The 3P was never designed as a sports car and has no artificial limits on top end power. It follows the voltage curve drop off at max amps.

The pic. below is a post made to @eivissa a few years back.
My M3P ’21 was used to check the power output, Amps at different SOC.

The test was to see if there was a 1250A limit (rumor somewhere, I do not remember)
As we know there is upper limit to power output it was also interresting to get the same SOC but with different cell temps.
So I charged home, drove it down to 81% passing the (only) supercharger on this longer drive.

We can see that about 428-429kW is the output limit. Same max power with both colder and warmer battery.

We can also see that the amphs are lower with the warm battery at the same power, which comes from a lower voltage droop (higher viltage output)

-33C bat / 84-85% = 1310-1316Amphs at 427-429kW

-39C bat / 85% = 1290 Amphs at 428 kW.

Using the data with sboutthe same cell temp and bigger SOC range show us this:

Highest current at high SOC and reducing current with the SOC.

85% / 1314 / 429kW / 33.0 C

84%/ 1316 / 429 kW / 33.3C

84%/ 1310 / 427kW / 33.8C

81% 1328 / 426 kW / 29.8 C

80% / 1295 / 416kW / 32.3C

80% / 1285 / 413kW / 32.2C

70% / 1288/ 403kW/ 29.0C

70%/ 1293 / 403kW / 29.3C

60%/ 1290/ 390kW/ 27.3 C

60%/ 1278 / 392kW / 27.3C

I had 2 years of logs of all this but I probably goofed it when changing the logging to the Plaid.
Probably gone, otherwise it still is on the disc but not checked yet.

I know @eivissa has logs and did dig deep into the different batteries and the inabillity for the LG pack to deliver the same power as the Panasonic.

I have been playing with R/C helicopters since ~2007. (Thats where my interrest of lithium batteries started)
The normal setup is having a overdimensioned electonic speed controller (ESC) able of higher currents than the battery can deliver.
This means a full power climb is not dependent on the current capacity of the ESC, and the output voltage of the battery will be the limiting factor which in turn is depending on the internal resistance and SOC.
Living at about the artic circle it was evident that cood battery pack could not deliver the power needed (due to the internal resistance, causing to much voltage droop.
The behaviour on the M3P is very like, when the battery is limiting the power by voltage output.

Tesla initially limited the min voltage on my M3P (probably due to using a new cell type, 2170L). This ended up making the car very power limited at low SOC and cold WX.
When they reduced that limit, and allowed for higher viltage droop at low SOC, the power got much better

If you oversize the controller and cooling you can optimize (limit) the bottleneck of the battery output.

 

[gearchruncher]

I have been playing with R/C helicopters since ~2007. (Thats where my interrest of lithium batteries started)

A 5C discharge in a Tesla is nothing like the 60C+ you're doing in RC helicopters.

Plus, the Plaid uses the EXACT same controller board part number as the Model 3. The plaid board even says "Model 3" on it. This is not a controller issue, nor a cooling issue.

Please, explain to me how 15% more battery voltage can take a motor from going from being peak output at 6000 RPM to holding power all the way to 16,000 RPM? And why anyone bothers to go to 800V architectures when that would just blow up a 320V motor? Why are we assuming there is only one motor on the planet and only batteries can change?

This is why it's so exciting that there is evidence that they changed the Model 3 rear motor- they can make much, much more difference in performance with that instead of just re-configuring the cells from 96S to 110S, and unless they are trying to make the M3P go 200MPH, it's not even clear 110S would do anything for a Plaid motor at lower RPM.

 

[momo3605]

Sport Auto Drove the Ioniq 5N and did 7min45 on the full lap with P-Zero Corsa. Would have been in the 7min 30's with extreme tires (CUP2R for example)

Absolutely no performance degradation during the lap, power stayed consistent the whole time. (Plaid in limp mode after 3.5min, same for a current 3P). Car is also able to do 0.6G in regen alone, so brakes are holding great (not like Tesla on stock setups...)

This powertrain on another platform (sedan/sport car) would be pretty insane.

I'm certain a 600HP Model 3 would do significantly better if it was able to maintain power during the entire lap, since it is a lot lighter. Issue is that Tesla is far from the competition as far as cooling, so not likely to happen with the highland IMO. I will not start again 400V vs 800v, but I have my strong opinion on that matter for performance EVs.

I hope Tesla will step up this time, pretty sure acceleration will be great, pretty sure cooling will be bad again and we end up again with a half lap setup...

This is actually not bad. For a car with 600hp, it's not far off the Taycan Turbo S which is more powerful (750hp) and did a 7:35 on (much wider) Corsas.

 

[Nabush]

The article says, "And this time was apparently achieved on a damp track that had plenty of other cars on it." Perhaps it would have been 20s faster without those impediments.

The main point I was trying to make is that it really shouldn't take much at all for the Highland variant of a M3P be faster than the Ioniq N, and likely at a lower price.

The article is full of imprecisions...Need to see if there is a video of the lap...

Model 3 chassis is very capable, but not in stock form. And without full power on the whole lap (so cooling) it will be difficult to go under 7min 45.

Taycan is 5,100 lbs and ran a 7:08. Plaid is 4,800 lbs and ran a 7:25. Weight just isn't what it used to be with modern tires and EV acceleration.


Sure, Plaid backs off from 1000HP, but does it dip below 600HP? One way to get thermals managed is to just not allow peak power, and there is a world of time between 7:45 and 7:39 (Plaid only gained 5 seconds going from MP4S to 200TW tires), so it's not like thermals are killing Tesla from setting times on equivalent weight cars that are better than the competition.

I'd love a 750HP peak Model 3 that backs of to 550HP if you flog it for a while more than a 600HP car that just holds that forever.

Plaid power drops to 350KW in limp mode

 

[mpgxsvcd]

View attachment 1010431
The pic. below is a post made to @eivissa a few years back.
My M3P ’21 was used to check the power output, Amps at different SOC.

The test was to see if there was a 1250A limit (rumor somewhere, I do not remember)
As we know there is upper limit to power output it was also interresting to get the same SOC but with different cell temps.
So I charged home, drove it down to 81% passing the (only) supercharger on this longer drive.

We can see that about 428-429kW is the output limit. Same max power with both colder and warmer battery.

We can also see that the amphs are lower with the warm battery at the same power, which comes from a lower voltage droop (higher viltage output)

-33C bat / 84-85% = 1310-1316Amphs at 427-429kW

-39C bat / 85% = 1290 Amphs at 428 kW.

Using the data with sboutthe same cell temp and bigger SOC range show us this:

Highest current at high SOC and reducing current with the SOC.


I had 2 years of logs of all this but I probably goofed it when changing the logging to the Plaid.
Probably gone, otherwise it still is on the disc but not checked yet.

I know @eivissa has logs and did dig deep into the different batteries and the inabillity for the LG pack to deliver the same power as the Panasonic.

I have been playing with R/C helicopters since ~2007. (Thats where my interrest of lithium batteries started)
The normal setup is having a overdimensioned electonic speed controller (ESC) able of higher currents than the battery can deliver.
This means a full power climb is not dependent on the current capacity of the ESC, and the output voltage of the battery will be the limiting factor which in turn is depending on the internal resistance and SOC.
Living at about the artic circle it was evident that cood battery pack could not deliver the power needed (due to the internal resistance, causing to much voltage droop.
The behaviour on the M3P is very like, when the battery is limiting the power by voltage output.

Tesla initially limited the min voltage on my M3P (probably due to using a new cell type, 2170L). This ended up making the car very power limited at low SOC and cold WX.
When they reduced that limit, and allowed for higher viltage droop at low SOC, the power got much better

View attachment 1010431

Model 3 does more than 429 Kw from the battery. I have seen as much as 448 Kw with a fully optimized battery.

I can make the car at 16% SOC perform like the same car at 89% SOC just by changing the battery temperature.

Here are two max discharge values at different temperatures and SOC. 365 KW is ~490 HP.

 

[AAKEE]

A 5C discharge in a Tesla is nothing like the 60C+ you're doing in RC helicopters.

You newer actually use 60C. 60C would empty the battery in 1 minute from 100% to 0%.
The batteries might be rated (elon lying wise, mostly) to 60C. The average C might be 8C (6 minutes flight time, using 80%)

It actually do not matter even if 60C was used. The limiting factor and the result from that will be the same.

Plus, the Plaid uses the EXACT same controller board part number as the Model 3. The plaid board even says "Model 3" on it. This is not a controller issue, nor a cooling issue.

Please, go back and point out where I said it was a controller issue


I state the complete opposite:
The voltage droop cause the motor to deliver less power.
Increasing the battery voltage so the lowest voltage > the motor need to deliver the set power

Please, explain to me how 15% more battery voltage can take a motor from going from being peak output at 6000 RPM to holding power all the way to 16,000 RPM?

By having a higher supply voltage you can counter the back EMF with increased voltage to keep the power at higher rpm.

A M3P solution already use all the available voltage.

And why anyone bothers to go to 800V architectures when that would just blow up a 320V motor? Why are we assuming there is only one motor on the planet and only batteries can change?

The change to 800V was not made to outperform the Plaid.

Double the Voltage makes it possible to reduce the wiring avg. = less costs, less weight.
Also, higher voltage = less losses. The ohmic losses is squared to the current, by doubling the voltage we cut the current in half and the losses by four.

This is why it's so exciting that there is evidence that they changed the Model 3 rear motor- they can make much, much more difference in performance with that instead of just re-configuring the cells from 96S to 110S, and unless they are trying to make the M3P go 200MPH, it's not even clear 110S would do anything for a Plaid motor at lower RPM.

Below about 100-120kph, the plaid is torque limited (you only need slightly cold asphalt to feel the vibrations from constant wheel spin and power regulations.)

The higher voltage will help with this:

- Being able to keep the power on lover SOC by still having the voltage the motor needs to produce the full power*.

-Being able to add voltage above the torque limit speed to keep the power.


I hope everyone understands that the real power curve of the M3P motor is not what we see in the graphs.
The electric motor would be able to produce very much torque at low rpm but the car need to limit the torque due to both tyre grip and gearbox limits.

 

[AAKEE]

Common misconception since Elon likes to lie about this.

! …

Probably a side track / off topic here.

I never checked it or even thought about it.
I know the gear ratios is defined in the EPA tests.

A check and a calc showed that the M3P had 18.600rpm at top speed (261kph), and the plaid 18.200 rpm at 322kph.

Do we have another thread already, or is it time to start one?

 

[gearchruncher]

A check and a calc showed that the M3P had 18.600rpm at top speed (261kph), and the plaid 18.200 rpm at 322kph.

Do we have another thread already, or is it time to start one?

I literally linked to where I did this math 18 months ago and I've posted it anytime someone talks about the magic 20K RPM of the Plaid. Nobody cares. All you can do is learn and then correct people when they claim the reason for the carbon overwrap is to allow higher RPM.