Suggestions for EV Kart inclusion in SCCA Autocross

hallkbrdz

100 W
Joined
Mar 24, 2018
Messages
239
Location
Edmond, OK USA
With the prompting by my local SCCA chapter I've been working on some suggestion rules / guidelines for EV Karts in SCCA Autocross, since they are currently not allowed due to a lack or regulations. What I have so far is a mashup of the Formula SAE rules and the FIA EKarting rules, applying commonly used terms for items instead of engineering terminology. I still am working on the portion dealing with incident safety and mitigation, but I'd like to put out what I have so far for constructive feedback.

File link (I will keep the same link, and just change the date at the top as I make revisions):

https://drive.google.com/file/d/1ZR1VEhMDuBwZuTooHfdGT1B8oFGMVrKv/view?usp=sharing

Thanks in advance,

Bryan
 
The following is coming from someone who has dealt with rulebooks for SCCA rallycross, FIRST robotics, and lots of industry spec/engineering documents.

2.1.7 C5 Capacity should probably be defined, at least for people doing the tech inspection. How is going to be enforced as well? C5 is not a common rating, and if these are home built they may be reusing batteries, nameplate capacity might be an easier thing for tech to look for.

2.1.9 This says that the HVD must be used to disconnect the traction battery when performing maintenance, but then continues to give other examples. It is unclear whether these are in addition to the HVD or giving additional examples of what is a valid HVD. If they are additional examples they should be in the HVD section, if they additional valid options it should be reworded all together.

Under 2.1.11 "If triggered the fuse will not automatically reset...". This makes me think the circuit breakers are allowed, but with the section called "Overcurrent fuses", I'm not sure. If the intent is to allow circuit breakers perhaps rename this section to "Overcurrent protection" or something along those lines.

Nassau panel should probably be in the definitions section, if not for the competitor, for the workers who might need to use it and are not familiar with karting terms.

2.1.15 "Complete galvanic separation of the entire Tractive System and LV System is required.
Some components such the Motor Controller / Inverter and BMS utilize both HV and LV."
These sentences seem at odds with each other, how can we have complete galvanic separation when some components utilize both (I do know it's possible to keep the isolated internally), or are only devices that maintain separation allowed to be used? Galvanic separation should probably be defined as well.

IMD Is this Isolation or Insulation Monitoring Device - it's referred to as both, should pick one and stick with it, even if both are acceptable terms.

Are the tech inspectors in your area familiar with high power/high voltage EV's? If they are not I think there could be a lot of teething issues with the rules as they are written. I have a hard time seeing how a tech person on the day of the even could enforce "The maximum traction battery power will not exceed 60 kW." If they're at the max voltage of 180v, that means they could have a max current of ~333 amps, if they have a 10kWh nameplate battery, does the tech need to lookup the data sheet for the cells and make sure they have 30C rating or less? Or do they need to check the BMS programming/Overcurrent protection device?

Just some thoughts
 
Egdinger - Thanks for you review and your questions. Although I have greatly simplified the criteria from the original sources, I agree many of them are still rather complex for the average person without much knowledge of EV systems and am trying to come up with simpler ways to quantify the total energy within the traction battery, such as possibly overall weight.

I will definitely revisit the sections you cited and try to make them more clear without adding any further complexity.

Regards,
Bryan
 
Posted a hopefully clearer and simpler version.

I think total weight (not 100% on the number) is the way to go to control capacity, with the main goal of safety. Easy to check.
 
Back
Top