The University of Washington EcoCAR2 team (UWEC2) is currently in the process of building a Plug-in Hybrid Electric Vehicle (PHEV) for the EcoCAR2 Challenge. This competition challenges 15 universities across North America to reduce the environmental impact of a 2013 Chevrolet Malibu without compromising consumer acceptability. In order to be competitive in EcoCAR2, grid electricity is relied on heavily and the use of the Utility Factor method presented in SAE J2841 - Utility Factor Definitions must be used to compare emissions and consumption results with traditional vehicle results.
Powertrain simulation in Autonomie was performed to explore many different hybrid architectures. The simulation results were normalized using the Utility Factor method to reach final architecture and component decisions. The architecture chosen by the team to address the competition goals is a Parallel Through The Road (PTTR) PHEV which provides all electric operation to eliminate petroleum usage on short trips, four wheel drive mode to improve utility performance for consumers, and efficient charge-sustaining hybrid operation. The PTTR architecture is the lowest cost architecture to provide all of these benefits, and it does so without compromising the safety performance of the platform.
The front powertrain consists of a General Motors (GM) 100kW 1.7L LUD Turbo Diesel internal combustion engine running on B20 as a range extender. On the rear powertrain there is a 150kW peak Remy HVH250 Rear Traction Motor (RTM) mated to a GKN gearbox with a 9.59:1 gear ratio. Powering the rear powertrain is an 18.9 kWh A123 Energy Storage System (ESS). The nominal voltage of the system is 340V.
This paper will present the development of the UW EcoCAR2 team's vehicle design, with justification on major decisions coming from a Utility Factor standpoint to explore the importance of using of grid electricity in transportation.