Optimization and Testing of a Through the Road Parallel, Hybrid-Electric, Crossover Sports Utility Vehicle

The University of Wisconsin Hybrid Vehicle Team has implemented and optimized a four-wheel drive, charge sustaining, split-parallel hybrid-electric crossover vehicle for entry into the 2008 ChallengeX competition. This four year project is based on a 2005 Chevrolet Equinox platform. Fuel economy, greenhouse gas impact (GHGI), acceleration, component packaging and consumer acceptability were appropriately weighted to determine powertrain component selections. Wisconsin's Equinox, nicknamed the Moovada, is a split-parallel hybrid utilizing a General Motors (GM) 110 kW 1.9L CDTi (common rail diesel turbo injection) engine coupled to an F40 6-speed manual transmission. The rear axle is powered by a SiemensVDO induction motor/gearbox power-limited to 65 kW by a 40-module (288 volts nominal) Johnson Controls Inc, nickel-metal hydride battery pack. The vehicle is fueled by a 20% blend of biodiesel (B20), which has a lower greenhouse gas impact GHGI impact and petroleum content than conventional diesel fuel. The Moovada generates 175 kW of total power with a curb weight of 1838 kg. It performs a 0-60 mph acceleration in a mere 8.17 seconds. Using its diesel electric power train, when measured hot, it met the Tier 2 Bin 5 emissions certification and achieving a 36.5 mpg (15.5 km/L) combined fuel economy on the EPA cycle. This paper summarizes the testing, optimization and implementation of both the components listed above as well as the unique integration strategies employed by the Wisconsin team to achieve the fuel economy and emissions targets of the ChallengeX competition.