Goals
- Integrate a EV charger into the vehicle such that MSXII can be recharged at any public J1772 L2 charger in North America
Background and strategic fit
With ASC 2018 and WSC 2019, cruiser class vehicles are allowed to recharge off of the grid. Previously, the team has used DC power supplies to charge our batteries, but in order to make MSXII more practical and "consumer" friendly, we are planning to integrate a Level 2 EV charger into the vehicle. With this charger, we should be able to plug into any public Level 2 charger and recharge within hours.
Assumptions
- The user should not have to do anything else other than plugging the J1772 connector in to initiate charging
Requirements
| # | Title | User Story | Importance | Notes |
|---|---|---|---|---|
| 1 | Level 2 Charger | This charger should be able to recharge off of 220-240VAC mains power | Must have |
|
| 2 | J1772 connector | This connector is the standard for Level 2 AC charging and Level 3 DC Fast Charge in North America | Must have |
|
| 3 | Charge indicator | The charging information (status, power, time remaining if possible) should be displayed to the driver | Nice to have |
|
| 4 | Safety | The vehicle should not be allowed to go into drive or reverse charging | Must Have |
|
Questions
Below is a list of questions to be addressed as a result of this requirements document:
| Question | Outcome |
|---|---|
| How is the charging algorithm defined? | We need to set the voltage and current every second, so we have to write the algorithm ourselves |
| How do we communicate with the charger? | We have to talk to it via CAN bus, meaning that we'll use another CAN translator board (Motor Interface) |
| How do we plan on charging during the race if there are no EV chargers along the route? |
Not Doing
- DC Fast Charge (More complex negotiations between charger and vehicle, also have to bypass the charger if we do that)
- Support for multiple connectors/protocols