Approaches for cooling the motor?

[nick]

Once the motor hits the first yellow the car backs off the power, gets slower and slower (no error message).

At Laguna Seca it would blast up the hill once, but I could watch the current (A) number back off further and further the second time up the hill.

Flooring it from a stop - weak acceleration. Give it a few minutes to cool - back to normal power.

Any thoughts on cooling the motor?

 

[dhrivnak]

Dry ice???

 

[nick]

Maybe some form of compressed gas that could be released into the motor when it gets hot (based on CAN messages).

 

[nick]

Plan...

CO2 tank in the trunk, regulator and control valve, piped to a nozzle near the motor.
Hardware to monitor the CAN bus for temperature information, logic to trigger/control the release of CO2 through the motor.

 

[Ampster]

Plan...

CO2 tank in the trunk, regulator and control valve, piped to a nozzle near the motor......

How about nitrogen? Ironic that an EV would use CO2 for cooling.

 

[hcsharp]

The idea of using nitrogen has been kicked around before. I wonder where the heat is building up - the rotor or the stator? It will be hard to remove heat from the rotor.

 

[Tesla 940]

I was at Laguna Seca all three days of the Refuel event - had a blast. I usually ran 6 or 7 laps before noticeable reduced power. The first session each day was full power the entire 25 minute sessions. Interesting that you are losing power so soon.

 

[wiztecy]

I believe Nick has a 1.5, however the motors should be the same. Possibly they're driving them a bit differently. Would be interesting to see if another 1.5 experienced the same issues on the same day. The other possibility is the blower setup on the motor. The 2.x's ( with the updated blowers) I believe are able to force more air and possibly may be driving more current to the blower which would help reduce motor temps.

 

[nick]

I was at Laguna Seca all three days of the Refuel event - had a blast. I usually ran 6 or 7 laps before noticeable reduced power. The first session each day was full power the entire 25 minute sessions. Interesting that you are losing power so soon.

#940... I wonder if the 2.0/2.5 has better motor cooling than my 1.5.

I couldn't complete a start-to-start lap at full power after entering the track... get on the track between 2 and 3, full power around the track and back to the hill... then by the top of the hill it was losing power... about 380A instead of >500A. On the first session I tried to do one more lap and it maxed out at 202A up the hill.

As a test I tried flooring it from a standing stop in pit lane - car slowly rolled forward.
I waited 2 minutes for the motor to cool off one notch back to blue - back to full power.

On the plus side I got my time down to ~2m03s (measured with a GoPro using the turn 3-4 Michelin bridge as the start/finish marker so not an official time). New Toyo R888R tires and at a lower pressure made a huge difference.

Edit: painfully boring video of the lap:

 

[nick]

The 2.x's ( with the updated blowers) I believe are able to force more air and possibly may be driving more current to the blower which would help reduce motor temps.

I wonder if the 2.x blowers would fit on a 1.5...

 

[snd92]

I wonder if the 2.x blowers would fit on a 1.5...

I have a 2.0 with some 1.5 parts, e.g seats. Maybe these parts will fit 1.5

 

[wiztecy]

I think you guys are missing it, you need the firmware to drive the updated 2.x fans/blowers. Its one motor with two fans/blowers. They're driving more current hence why the fans power on and when they get hot, spool faster. This is also the reason why the fan / PEM connector gets melted by driving it at and possibly past its rating. When either the motor or PEM temps rise the fan goes into overtime. So if it detects the PEM heating, the motor will get cooled down as a by product since its one motor and two fans. And visa versa, if the motor needs cooling the PEM will get cooling due to the cooling system running off of the same motor.

PEM, motor gets too hot -- fans failed

 

[snd92]

Tesla did also change fuse #12 to 30 A. Found a seller in Norway. Nye Kjølevifter til Tesla Roadster, Oppgradert modell.

 

[Tesla 940]

Nick, My best time was on day 3 at 2:03.6 using a SOLO timer. I had new AD07's front and moderately worn MPSS on the rear. I'm rather cautious with the car so I don't expect my times at any track to ever be impressive - but I do have fun. All my other track days (about 12) have been on Streets of Willow or Big Willow.

 

[nick]

Nick, My best time was on day 3 at 2:03.6 using a SOLO timer. I had new AD07's front and moderately worn MPSS on the rear. I'm rather cautious with the car so I don't expect my times at any track to ever be impressive - but I do have fun. All my other track days (about 12) have been on Streets of Willow or Big Willow.

This was my first time hitting 2:03.something. New set of Toyo R888R tires.

On turns 3 and 4 the car tracked out nicely under acceleration with the new tires.

 

[dgaultiere]

What about good old water-cooling with some piping around the motor and a radiator?

 

[Drocer]

I think you guys are missing it, you need the firmware to drive the updated 2.x fans/blowers. Its one motor with two fans/blowers. They're driving more current hence why the fans power on and when they get hot, spool faster. This is also the reason why the fan / PEM connector gets melted by driving it at and possibly past its rating. When either the motor or PEM temps rise the fan goes into overtime. So if it detects the PEM heating, the motor will get cooled down as a by product since its one motor and two fans. And visa versa, if the motor needs cooling the PEM will get cooling due to the cooling system running off of the same motor.

PEM, motor gets too hot -- fans failed

I was dropping AC in my Roadster in summer until my single fan setup went bad and the SC upgraded me to the dual fan configuration. All my overheating problems stopped after the upgrade.

 

[hsull8915]

I was dropping AC in my Roadster in summer until my single fan setup went bad and the SC upgraded me to the dual fan configuration. All my overheating problems stopped after the upgrade.

I was under the impression that the fan upgrade only helped with PEM and motor cooling, while AC was only re-routed for battery cooling. Does the fan assist with battery temps and/or does AC assist with PEM/motor?

 

[hcsharp]

I was under the impression that the fan upgrade only helped with PEM and motor cooling, while AC was only re-routed for battery cooling.

That's correct.

 

[nick]

The last parts are arriving Saturday for a not-in-car CO2 cooling test.

20lb CO2 tank (aluminum tank at 24lbs plus 20lbs of CO2), inverted to draw off liquid CO2 from the bottom (the tanks with a siphon tube are steel and much heavier), running tank pressure down the lines (3000psi rated), feeding two nozzles which go from ~800psi liquid CO2 to spraying mostly fine dry ice.