The U.S. Department of Energy (DOE) has invested considerable research and development (R&D) effort into Plug-in Hybrid Electric Vehicle (PHEV) technology because of the potential fuel displacement offered by the technology. DOE's PHEV R&D Plan [1], which is driven by the desire to reduce dependence on foreign oil by diversifying the fuel sources of automobiles, describes the various activities required to achieve the goals. The U.S. DOE will use Argonne's Powertrain Systems Analysis Toolkit (PSAT) to guide its analysis activities, stating, "Argonne's Powertrain Systems Analysis Toolkit (PSAT) will be used to design and evaluate a series of PHEVs with various 'primary electric' ranges, considering all-electric and charge-depleting strategies." PSAT was used to simulate three possible chargedepleting (CD) PHEV control strategies for a power split hybrid. Trip distance was factored into the CD strategies before the cycle was started. The results are examined in this paper to determine if any of the three strategies could reduce the power split configuration's fuel consumption beyond what a simple all-electrical strategy followed by a charge-sustaining (CS) strategy could afford. The results show that the improvements for this configuration are small and depend on the ratio of the engine efficiency when operating in CS mode to the engine efficiency when operating in CD mode.

Hybrid electric vehicles have demonstrated their ability to significantly reduce fuel consumption for several medium-and heavy-duty applications. In this paper we analyze the impact on fuel economy of the hybridization of a tractor-trailer. The study is done in PSAT (Powertrain System Analysis Toolkit), which is a modeling and simulation toolkit for light-and heavy-duty vehicles developed by Argonne National Laboratory. Two hybrid configurations are taken into account, each one of them associated with a level of hybridization. That increases the braking energy recuperation rates. We first analyze the benefits of the two hybrid configurations on standard cycles. We then compare fuel economy results from a short standard highway cycle with a longer cruising scenario to illustrate the sensitivity of the benefits to the drive cycle. Finally, using simulation involving a grade scenario of periodical hills that we designed for this project, we show hybridization can be beneficial on hilly terrain.

4Plug-in hybrid electric vehicles are a promising alternative to gas-only vehicles and offer the potential to greatly reduce fuel use in transportation. Their potential energy consumption is highly linked to the size of components. This study focuses on the impact of the electric system energy and power on control and energy consumption. Based on a parallel pre-transmission architecture, several vehicles were modeled, with an all-electric range from 5 to 40 miles on the UDDS, to illustrate various levels of available electric energy. Five others vehicles were created, with various levels of power and same battery energy. The vehicles were then simulated under optimal control on multiple combinations of cycle and distance by using a global optimization algorithm. The global optimization algorithm, based on the Bellman principle, ensures a fair comparison between different vehicles by making each vehicle operate at its maximal potential. The results from each optimization are thoroughly analyzed to highlight control patterns. The potential minimal fuel consumption that can be achieved by each of them is presented. The results can also be used to find the potential minimal greenhouse gases emissions.

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