HEVT’s Rear Traction Motor

Virginia Tech’s controls subteam worked tirelessly with the control code to spin its rear traction motor (RTM) during Year Two. In the early hours of spring morning, the team’s hard work paid off, and HEVT saw the RTM spin for the first time!

The 125 kW rear traction motor is mounted on the rear subframe, which enables the team to power the vehicle in all electric mode. First, the mechanical subteam made modifications to the rear subframe and designed mounts for the motor and single speed transmission to which it is coupled. Then the electrical subteam stepped in to ensure that all of the high-voltage wiring was connected correctly and safely from the energy storage system to the inverter and then to the RTM.

The controls team then came in to make it all work together. Throughout Year Two, the team created and tested the code for this very moment. “We have been developing the control code since year 1 using logic blocks in MATLAB Simulink,” said controls subteam leader Kyle Caroncino.

The control code is loaded onto the MicroAutoBox, graciously donated by competition platinum-level sponsor dSPACE. The control code is then manipulated to satisfy the necessary “component-enable” conditions based on the readiness level of the vehicle. Only after each of the components involved have been properly enabled will the battery send high-voltage electricity to the rear-traction motor.

After many long nights working in the Ware Lab, the team was able to send commands to the RTM and spin the wheels – check it out in the video below!

“It’s neat seeing all of the components we’ve been installing over the course of the year actually working together,” Kyle said. “It’s a visual recognition of our hard work.”