EXPLORING THE FUEL ECONOMY POTENTIAL OF ISG HYBRID ELECTRIC VEHICLES THROUGH DYNAMIC PROGRAMMING |
G.-Q. AO, J.-X. QIANG, H. ZHONG, L. YANG, B. ZHUO |
Shanghai Jiao Tong University |
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ABSTRACT |
Hybrid electric vehicles (HEV) combined with more than one power sources have great potential to{{br}}improve fuel economy and reduce pollutant emissions. The Integrated Starter Generator (ISG) HEV researched in this paper is a two energy sources vehicle, with a conventional internal combustion engine (ICE) and an energy storage system (batteries). In order to investigate the potential of diesel engine hybrid electric vehicles in fuel economy improvement and emissions reduction, a Dynamic Programming (DP) based supervisory controller is developed to allocate the power requirement between ICE and batteries with the objective of minimizing a weighted cost function over given drive cycles. A fuel-economy-only case and a fuel & emissions case can be achieved by changing specific weighting factors. The simulation results of the fuel-economy-only case show that there is a 45.1% fuel saving potential for this ISG HEV compared to a conventional transit bus. The test results present a 39.6% improvement in fuel economy which validates the simulation results. Compared to the fuel-economy-only case, the fuel & emissions case further reduces the pollutant emissions at a cost of 3.2% and 4.5% of fuel consumption with respect to the simulation and test result respectively. |
Key Words:
ISG Hybrid electric vehicle, Supervisory controller, Dynamic programming, Cost function |
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