VMOD-4: Powertrain Thermal Model

[rhorvath02]

Powertrain Thermals

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1. Run experiments to characterize PTN thermals (HV battery, LV battery, motor, inverter)
2. Build first principles models (finite difference may work if you can use lumped capacitance assumptions)

3. Compare first principles models to experimental results

   • [ ] HV battery tests
   • [ ] LV battery tests
   • [ ] Motor tests
   • [ ] Inverter tests
   • [ ] HV battery first principles model
   • [ ] LV battery first principles model
   • [ ] Motor first principles model
   • [ ] Inverter first principles model
   • [ ] First principles models and experimental result agreement
   • [ ] Modify first principles parameters to agree with experimental results (assuming similar order of magnitude)
   • [ ] Add current sensors to output HV battery open circuit and terminal voltage

   • [ ] Add current sensors to output LV battery open circuit and terminal voltage

Reach out to rhorvath@utexas.edu with additional questions. This is tricky even if you've taken heat transfer.

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[Corbin175]

I want to split the cooling function into two functions: battery cooling & motor/inverter cooling.

I linked the code I wrote for battery thermals that I want to integrate into Vmod.

Can you give me some advice on how to do that effectively?

[Corbin175]

One of my concerns is that one of functions in powertrain_model.py returns current. However, I think current should be an imput into the battery cooling function. Is that okay?

[Corbin175]

Also how big is the time step for powertrain_model.py?

[rhorvath02]

One of my concerns is that one of functions in powertrain_model.py returns current. However, I think current should be an imput into the battery cooling function. Is that okay?

yeah, you can do that

[rhorvath02]

Also how big is the time step for powertrain_model.py?

The current time step is 0.003 seconds, but that's flexible. lmk if there's a reason to change that and we can reevaluate.

[rhorvath02]

I want to split the cooling function into two functions: battery cooling & motor/inverter cooling.

I linked the code I wrote for battery thermals that I want to integrate into Vmod.

Can you give me some advice on how to do that effectively?

Feel free to split this into two functions. The current setup is pretty cluttered, so more organization is better haha

[rhorvath02]

I want to split the cooling function into two functions: battery cooling & motor/inverter cooling.

I linked the code I wrote for battery thermals that I want to integrate into Vmod.

Can you give me some advice on how to do that effectively?

As for the battery thermal calc implementation, go ahead and start with adding a new function. For now you can define all of the constants as function arguments, and only calculate the delta over the time step. Go ahead and return the T_increase and we'll handle the summation in the main vehicle model file.

The philosophy here is that the system models handle all the low-level calculation while the vehicle model file handles all the higher-level system and inter-system calculations.

[rhorvath02]

lmk if all of that made sense. I can hop on call if needed too

[Corbin175]

Okay that all makes sense. I made changes to the code and then committed it. However, it says I cannot push origin. Do you need to approve something on your end to allow me to push?

[rhorvath02]

Okay that all makes sense. I made changes to the code and then committed it. However, it says I cannot push origin. Do you need to approve something on your end to allow me to push?

Try:

git push --set-upstream origin {your branch name}

your upstream branch might be directed at master which i protected the other day

[Corbin175]

Okay thanks. I think I was able to push my code

[rhorvath02]

Okay thanks. I think I was able to push my code

Just checked the commit log and it's on Github. I'm going to rebase on master quickly, so go ahead and pull when you get the chance.