DIY Electric Car Forums banner
21 - 34 of 34 Posts

·
Registered
Joined
·
24 Posts
Actually, Mojave, I'm assuming I can send a CAN signal to an arduino via the VCU, and just have the arduino interpret the CAN message into a PWM signal that drives the A/C compressor... I already have the PWM signal setup to output correctly from an arduino to drive the compressor. I'd just be changing my code logic on the arduino to interpret a CAN message instead of a temperature value from an external sensor. That would in theory let me retain climate control via the vcu, correct? I'm assuming that all interfaces and supports programmable behavior via the carbon display?
 

·
Registered
Joined
·
14 Posts
I think I am misunderstanding something here. I'm intending to use a traditional coolant system and Tesla coolant heater for temperature control of the batteries. I expect I'll be able to manage both of those through the VCU, correct?
Yes. The ability to add the A/C chiller to either the battery or inverter cooling loops just gives you more options when ambient temps are very high and you are loading the systems. Not terribly necessary for the battery loop but supercooling the motor/inverter loop before a run allows you to run harder longer.
 

·
Registered
Joined
·
14 Posts
Actually, Mojave, I'm assuming I can send a CAN signal to an arduino via the VCU, and just have the arduino interpret the CAN message into a PWM signal that drives the A/C compressor... I already have the PWM signal setup to output correctly from an arduino to drive the compressor. I'd just be changing my code logic on the arduino to interpret a CAN message instead of a temperature value from an external sensor. That would in theory let me retain climate control via the vcu, correct? I'm assuming that all interfaces and supports programmable behavior via the carbon display?
Yes, doing that essentially makes the system CAN controlled and the VCU would be fine with it.
 

·
Registered
Joined
·
24 Posts
Awesome, thanks Mojave! I'm completely unfamiliar with the idea of supercooling the motor and inverter.

How knowledgeable are you about the cooling needs of a tesla motor and battery modules? I'm not planning on dragging the car (Porsche 944 with Model S base LDU and 16 battery modules). I've got a couple questions around that topic in another thread if you're up on that side of the technicals.
 

·
Registered
Joined
·
18 Posts
I am not working on that specific project so I don't have dates or anything like that but I can say that it seems to either be complete and may just be in the buttoning up phase. Last I saw they were validating very high speed regen so there cant be much left if anything.

As to plug & play, well, you definitely need to read my response above regarding the system design function of the VCU200 & 300. I think the Tesla board version will be a little simpler since the motor is defined but you still have the rest of the vehicle to consider and how it will relate to the VCU. Also, I would definitely say it is not plug and play since to me that means you literally plug in the supplied harnesses and while there is one for the Tesla drive, the VCU does not have a generic harness, you need to build on so no plug & play for the VCU. Also, note that the control algorithm for the LDU controller is 100% CAN based, there is no stand alone mode for the LDU. Also the throttle pedal wiring does not go to the LDU either, everything needs to come in over CAN. That puts all the torque control functions into the VCU's hands, the LDU will no longer do anything but the most basic safety de-rate functions, shifting that over watch responsibility to the VCU and adjustable by the user. I'm not 100% sure, but I believe the CAN specs for the Tesla control board will also be published at the same time as the board is released so if someone wanted to control it with a different VCU or whatever, that will be possible as well.

I did however get to drive our mule Mustang with the VCU-200 & base LDU about a month ago and it was an absolute riot. I took it home for the weekend and scared my friends with 0-90 runs and overall put about 150 miles on it.

Any updates on the sport LDU drive unit board?
 

·
Registered
Joined
·
159 Posts
Throw me on this pile i guess, i just pulled the trigger on a vcu200 and it's sitting on my couch
Bisi of bisimoto made me do it, basically, his porsche K3v runs the vcu200

Although reading this thread gives me some pause, it sounds like I'll have to really architect the entire build around can communication between everything, which probably means making a lot of little CAN arduinos to take in can messages and spit out all kinds of signals to attached hardware
 

·
Registered
Joined
·
22 Posts
I don't think they have announced anything on that but I think its fair to say its in the works. I have no timeline or ETA.
Mojave, I'm interested in the Sport LDU board as well, however as an aerospace development engineer I'd love to be involved in Beta testing if you are looking for testers. My project is two sport LDUs in a 57 Chevy wagon
 

·
Registered
Joined
·
159 Posts
more i think on it, having everything on CAN doesn't sound so bad, converting from pwm to can will be the annoying part. i wonder if there are pe built arduinos with wifi chips for configuration or something built in
 

·
Registered
Joined
·
159 Posts

·
Registered
Joined
·
22 Posts
and is the plan to have an entirely separate board for sport units, or will this board be usable with sport units, just needs a firmware flash to do so?
I have been advised that it is only firmware to update to Sport motor. Guessing the motor BEMF is different for the higher voltage and therefore field weakening requirements are different. Something like that which means base and sport can't run the same firmware but hardware is same.

Why do you need ardunos? There is i/o onboard the VCU which can run things on a basic rig.
 

·
Registered
Joined
·
159 Posts
I was going by mojave's statement a bit back saying everything on CAN is easier, but i dont know if there are pins on the vcu200 for pwm fan control built in. If so that's pretty awesome and simplifies things
 

·
Registered
Joined
·
22 Posts
I was going by mojave's statement a bit back saying everything on CAN is easier, but i dont know if there are pins on the vcu200 for pwm fan control built in. If so that's pretty awesome and simplifies things
The instructions etc are available online. You'd need a PWM-capable solid state relay to handle the current of the fan
 

·
Registered
Joined
·
41 Posts
Just adding the info here because its semi relevant,

I spoke with AEM yesterday via email about a control solution for the SDU. They tell me that they are working on a drop in logic board for the SDU to work in conjunction with the VCU200, they are expecting it to be available to the public in Q2 2022.
There aren't a huge amount of options to drive the SDU, so its great to have another option on the market.
I'll be watching it very closely and at this stage its a high probablity that i'll be using it in my build.
 
21 - 34 of 34 Posts
Top