Until recently, U.S. government efforts to dramatically reduce emissions, greenhouse gases and vehicle fuel consumption have primarily focused on passenger car applications. Similar aggressive reductions need to be extended to heavy vehicles such as delivery trucks, buses, and motorhomes. However, the wide range of torques, speeds, and powers that such vehicles must operate under makes it difficult for any current powertrain system to provide the desired improvements in emissions and fuel economy. Hybrid electric powertrains provide the most promising, near-term technology that can satisfy these requirements.
This paper highlights the configuration and benefits of a hybrid electric powertrain capable of operating in either a parallel or series mode. It describes the hybrid electric components in the system, including the electric motors, power electronics and batteries. In addition, the paper illustrates the installation of this hybrid electric hardware into a 17,000 kg (GVW) military vehicle based on an RV chassis. The analyses of the new system show that conventional benchmarks for performance and fuel economy can be met or exceeded. In fact, fuel economy increased 50 percent on an urban cycle and 25 percent on average for five different cycles. Finally, the benefits of this powertrain for military initiatives such as the 21st Century Army and 21st Century Truck Initiative will be discussed, including how the Dual-Use Hybrid Electric Command and Control Vehicle can provide a source for up to 150 kW of auxiliary electrical power.