To complete the ESS Benchtesting checklist, the Purdue EcoMakers recently implemented a contactor closing procedure. Team member Andrew Senetar, who demonstrates the procedure in the video below, is one of a rare species on the Purdue EcoCAR team: an EE major! Now the team is working towards commissioning the ESS (energy storage system) by completing the fabrication and assembly of the battery box.
As Andrew demonstrates, a CANCaseXL (donated by Vector) and the 12V car battery from the donated Chevy Malibu are used to simulate the signals required by the BMS (battery management system) to close the contactors and perform other functions. The CANCaseXL also allows us to read the CAN messages that the BMS broadcasts and thus receive appropriate feedback and understand exactly what the BMS is doing. The controls people call this the CIL or component-in-the-loop testing. The CIL provides them with important information for modeling the real interface signals of the BMS and for deciphering the internal functionality of the BMS.
The goal is to replicate the entire vehicle function (including every single component) on a computer simulation. This will help the controls team ensure that the supervisory vehicle controller they designed is tested on this simulation and responds in a safe way to all possible errors, crashes or component failures. Because of this, when a real test driver takes the Purdue PHEV for its first spin on the road, there will be no risk of a failure that may cause any injury or damage.