The Design and Development of a Through-the-Road Parallel Diesel Electric Hybrid

Mississippi State University students in their third year of Challenge X competition have transformed a 2005 Chevrolet Equinox into a diesel-electric hybrid at a 99% buy-off vehicle readiness level. The vehicle, configured in a charge sustaining, through-the-road parallel architecture, offers significant improvements over the stock vehicle with a 45% increase in fuel economy and a 3.5% increase in 0-60 mph acceleration, while maintaining a Tier 2 Bin 8 EPA emissions rating with an impressive towing capacity of 2500 lbs. The MSU Equinox utilizes a 1.9 L diesel engine burning B20 biodiesel fuel with a six-speed manual transmission that is augmented by an ac induction electric motor-transaxle assembly. A nickel metal hydride (NiMH) battery pack provides sufficient energy storage to accomplish peak shaving so that the engine operates in its most efficient regime. Optimal vehicle performance was achieved with the powertrain system analysis toolkit (PSATtrade) and MATLABtrade that facilitated the design of an advanced vehicle architecture and control strategy to reduce energy consumption and emissions. Simulation results are compared with actual experimental data obtained on a four-wheel chassis dynamometer and road tests so as to validate the mathematical model. These studies together with several documented vehicle improvements bring the MSU Equinox to a 99% buy-off readiness level so as to comply with competition requirements.