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HEV Control Strategy for Real-Time Optimization of Fuel Economy and Emissions
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 02, 2000 by SAE International in United States
Annotation ability available
Event: Future Car Congress
Hybrid electric vehicles (HEV's) offer additional flexibility to enhance the fuel economy and emissions of vehicles. The Real-Time Control Strategy (RTCS) presented here optimizes efficiency and emissions of a parallel configuration HEV. In order to determine the ideal operating point of the vehicle's engine and motor, the control strategy considers all possible engine-motor torque pairs. For a given operating point, the strategy predicts the possible energy consumption and the emissions emitted by the vehicle. The strategy calculates the “replacement energy” that would restore the battery's state of charge (SOC) to its initial level. This replacement energy accounts for inefficiencies in the energy storage system conversion process. User- and standards-based weightings of time-averaged fuel economy and emissions performance determine an overall impact function. The strategy continuously selects the operating point that is the minimum of this cost function. Previous control strategies employed a set of static parameters optimized for a particular drive cycle, and they showed little sensitivity to subtle emissions tradeoffs. This new control strategy adjusts its behavior based on the current driving conditions. Simulation results of the RTCS and of a static control strategy on a PNGV-type baseline parallel HEV (42 kW engine and a 32 kW motor) using ADVISOR are presented. Comparison of the simulations demonstrates the flexibility and advantages of the RTCS. Compared to an optimized static control strategy, the RTCS reduced NOx emissions by 23% and PM emissions by 13% at a sacrifice of only 1.4% in fuel economy.
CitationJohnson, V., Wipke, K., and Rausen, D., "HEV Control Strategy for Real-Time Optimization of Fuel Economy and Emissions," SAE Technical Paper 2000-01-1543, 2000, https://doi.org/10.4271/2000-01-1543.
- Wipke, K. Cuddy, M. Burch, S. “ADVISOR 2.1: A User-Friendly Advanced Powertrain Simulation Using a Combined Backward/Forward Approach,” IEEE Transactions on Vehicular Technology, Special Issue on Hybrid and Electric vehicles Columbus, OH August 1999
- Hermance, David Sasaki, Shoichi “Hybrid electric vehicles take to the streets,” IEEE Spectrum November 1998
- Yamaguchi, Jack “Insight by Honda,” Automotive Engineering International October 1999
- Wipke et al. ADVISOR 2.2 Documentation September 1999
- Society of Automotive Engineers Hybrid-Electric Vehicle Test Procedure Task Force “SAE J1711, Recommended Practice for Measuring Exhaust Emissions and Fuel Economy of Hybrid-Electric Vehicles,” September 18 1998
- Vanderplaats, G.N. “Numerical Optimization Techniques for Engineering Design: With Applications,” 3rd Vanderplaats Research & Development, Inc. Colorado Springs, CO 1999