Tesla Cobra EV Project Update

[dougyip]

Thought some of you might be interested in a new YouTube video that outlines the development of our Telsla Cobra EV race car since it hit the track 4 years ago. The latest update is the move to a Tesla Model 3 Battery and Drive Unit. The drive unit controller is a CAN based Ingenext unit. We will definitely test the Open Source solution when it arrives. Charging is handled by three Gen2 Tesla units controlled by the V2 Open Source controllers.

[Bratitude]

Thanks for sharing, some of the photos in the video posted here would be awesome if you don’t mind. your charger setup looks awesome

[SRFirefox]

Nice work! Very cool on the upgrade to the M3 motor. What power rating do you think you would need for average power to balance performance, weight, and battery life for your sprint races, or is the M3 motor pretty good where it is already?

[dougyip]

You can never have too much power! From our limited data, we saw that we were able to put down an average of about 95kW with the M3 drive unit. Peak power was in the 220kW range. Peak for the Model S drive unit was much higher, but we were under 70kW average at the end of a race.

[JaniK]

Very cool, thanks for sharing

[EV_Builder]

You can never have too much power! From our limited data, we saw that we were able to put down an average of about 95kW with the M3 drive unit. Peak power was in the 220kW range. Peak for the Model S drive unit was much higher, but we were under 70kW average at the end of a race.

What whas controlling the Model S drive unit? Tesla's firmware or openinverter?

Ohh and indeed thanxs for sharing!

[dougyip]

Most of our operation was with EV-Controls CAN based system. However, we did test and use the Open Inverter system for one race before switching to M3 power. Dyno data from our testing of the Open Inverter system was posted on the forum.

[johu]

Here: viewtopic.php?p=4762#p4762

[thEVan]

Thanks for sharing!
Very exciting to see the potential of the Model 3 motor.
I’ve been looking for more info on the Ingenext controller and was hoping you could share a bit more info.
Are you using it at all for controlling your motor cooling circuit?
Their website says 300-400v batteries but I’m hoping it could go a littler lower than that. Have you run lower than 300V?
Thanks.

[dougyip]

We just run the motor cooling flat out. If you want to add thermostatic control, then you will have to add your own controller. 300V is a hard limit that the stock Tesla controller enforces. This is where an Open Source solution that replaces the Tesla controller would be an advantage.

[SRFirefox]

Out of curiosity, did you see much or any improvement running submersion or air cooling inside the Model S motor? Obviously at 90C running temps you don't have a huge need, but might those same upgrades work on the model 3 motor?

[dougyip]

There were some benefits with compressed air/mist cooling. Running fluid in the air-gap created more heat from friction than we removed.

You do not want to mess with the Model 3 cooling internal cooling design! Air gap is way smaller and there is a very efficient cooling scheme. Rotor cooling is not required. There may be benefits though of decreasing temperature in the external water loop and/or adding an auxiliary cooler to the oil loop. We will be experimenting with that this season.

[JockE28]

Intresting!

so the M3 Rear drive uinit could provide the same peak power as the old SDU?