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Chassis CAN Logging To ASCII Text Plus Graphing

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Mike, do you have the data files/excel sheets on your google drive? i think if you matched up the BatI currents as the start point then you would see how the torques peak and then the L jumps ahead on speed from the benefit of the extra 200 Amps. i might play with the data some if available, although i like your charts better than mine.

For the shorter burns from say 30-70, the current doesn't seem to ramp down at the tail end like it does with 0-90 acceleration runs, maybe less thermal load?

Look at the extremely steep slope of the current during the first 30msec after you release the brake in LauchMode--that is an insanely steep ramp up for a short time, and the Rtorque nearly instantly increases from 350 to 450 ft-lbs. That slope and the torque response are nearly identical in the before and after L charts for run after run, and one car to the next. i agree with Bill that it is programmed into the system and they are pushing it to the bleeding edge.

Probably something in the system (mechanical drivetrain?) is causing it to be limited at that 450 peak torque level, but the motor could easily produce more since it only takes 200 Amps for both motors to hit that peak.
 
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Mike, do you have the data files/excel sheets on your google drive? i think if you matched up the BatI currents as the start point then you would see how the torques peak and then the L jumps ahead on speed from the benefit of the extra 200 Amps. i might play with the data some if available, although i like your charts better than mine.

For the shorter burns from say 30-70, the current doesn't seem to ramp down at the tail end like it does with 0-90 acceleration runs, maybe less thermal load?

Look at the extremely steep slope of the current during the first 30msec after you release the brake in LauchMode--that is an insanely steep ramp up for a short time, and the Rtorque nearly instantly increases from 350 to 450 ft-lbs. That slope and the torque response are nearly identical in the before and after L charts for run after run, and one car to the next. i agree with Bill that it is programmed into the system and they are pushing it to the bleeding edge.

Probably something in the system (mechanical drivetrain?) is causing it to be limited at that 450 peak torque level, but the motor could easily produce more since it only takes 200 Amps for both motors to hit that peak.

Yep, they are all up there: https://drive.google.com/folderview?id=0BzwKZAn3p2LTVGRsdU9SMHpzUlk&usp=drive_web in the MikeBur directory. OOF today, so may be much later before I can "play" with any more graphs, though had a few ideas on how to make these comparison charts easier (way too much hand-editing for my liking ;-))
 
Here are the torque curves :

Left Axis :
-Green : Front Torque (Nm)
-Red : Rear Torque (Nm)
-Pink : TPS

Right Axis :
Blue : Speed

Same 77kph to 159kph run.

Torque.png


Note that speed (right axis) is in KPH, not MPH. 77kph to 159kph, 100% TPS, on a private road, which is also kind of narrow : this was a bit scary.

SOC was 88%, outside temp was pretty cold (-10C)
Max amp draw is 1164A
Max Power is 356kW

edit : woops, forgot to add : green is voltage, red is power and blue is speed.

kudos to wk057 for helping me with the stupid 15bit signed integer this morning!

Volts & kW
View attachment 112520

Same graph, with Current instead
View attachment 112519

Nice graphs. Don't suppose you have the torque plots for the front and rear motors? (This is where I'd expect the biggest difference between the 85D and the P85D)

(I have the C# source for those messages if that's what you are using)

- - - Updated - - -

Followup :

Interesting curve #2 :

Cruising at 100kph (on tacc) on flat terrain. Range mode is ON. I switch range mode off, then put it back on again. Rangemode = front motor only on a 85D too (odd...). Normal mode = almost 50/50 distribution.

RangeMode_ON_OFF_ON.png


And another one, 0-130kph. Bad start but you get the idea. Same as before :

Left Axis :
-Green : Front Torque (Nm)
-Red : Rear Torque (Nm)
-Pink : TPS


Right Axis :
Blue : Speed

Torque_0-130.png
 
Curve #2 is really interesting and shows a great picture of 'torque sleep' of the rear motor. It takes ~18-20 ft-lbs from the front motor while the rear 'sleeps', then ~10.5 ft-lbs from each motor to maintain that speed, then back to sleep for the rear and the front must pick up the load. What a great data capture you've made!

Are you able to read BatI currents? It would be interesting to compare the current or power used for the above scenario to see which is more efficient.
 
Updated/better 50-75 graph (I snuck in a capture this morning). I feel a lot happier with these, re. SoC, BatTemp, etc. etc.

2-25-16 50-75 Insane - Ludicrous Comparison Graph.PNG


And zooming in on the first second:
2-25-16 50-75 (Zoomed) Insane - Ludicrous Comparison Graph.PNG



I didn't know anyone was interested in range mode data. I have a few of these ;-)

Rear motor idling varying speed from 35-45mph
2-18-16 30-40 mph Range Mode.PNG



Controlled deceleration, with rear motor engaging occasionally
2-18-16 47-25 mph Range Mode.PNG



Coasting
2-18-16 25 mph coasting Range Mode.PNG
 
Wait, what? wk, you took yours into a Tesla service center for the ludicrous upgrade? And they didn't give crap about having a rooted Model S?

Legally, they aren't allowed to. It's my car. I didn't break anything and didn't do anything that prevented them from servicing the car.

So in short, yeah, that's correct. :)
 
Cool!

Although, for production runs like that I go to a friend who works for a company that has a turn-key setup. I give them the PCB design and BOM, they source it all (either from me or whoever), bill me at cost for the BOM items, and build however many I want, from 1 to 1,000,000. :) Generally only cost effective for 100 or more though.
When are you starting your reservation list? I'll take one. Do you want any data from a P85 Sig still on 6.2 (or just the P85D that has a Lud upgrade pending)? ;)
 
Rangemode = front motor only on a 85D too (odd...).
If some of the logic is shared with P85D, then it makes sense that the front motor is designated as the more efficient go-to motor for range optimization.

- - - Updated - - -

Updated/better 50-75 graph (I snuck in a capture this morning). I feel a lot happier with these, re. SoC, BatTemp, etc. etc.
I'm looking at the first graph at the 1.5s mark. It appears that the front torque is dropping while the rear torque is rising.

Two questions:
1. Does this indicate a weight shift (easier to get traction in the rear?)?
2. If would be interesting to see the combined torque around that 1.5s mark for the Lud data shown there. More specifically, I'm curious if the torque is steady or if there's an inflection point in overall torque across the transition from front to rear.
 
Mike,
If I read your latest graphs correctly, you are going from low current draw to max current in 0.25-0.30 seconds which makes the one second current ramp from a dead stop absolutely artificial. The battery can source much faster.

If Tesla's claim of front and rear motor HP is accurate, there is absolutely no motor limit reason the motors can not/should not produce more than 450/235.