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A Gear Shifting Indication Strategy of Eco-driving Vehicle
ISSN: 0148-7191, e-ISSN: 2688-3627
To be published on April 14, 2020 by SAE International in United States
The current indication strategy of gear shifting indication system for manual transmission vehicles is developed based on the gear shifting strategy of the automatic transmission. In this paper, the driving data of several automatic transmission and manual transmission vehicles are collected. It is found that the shifting frequency of automatic transmission vehicles is significantly higher than that of manual transmission vehicles, which increases the fatigue of drivers. Aiming at this problem, an interval algorithm of gear shifting indication strategy is proposed based on the fuel consumption rate of engine in this paper. The strategy uses genetic algorithm to process the data of fuel consumption rate, finding the maximum and minimum values in the interval of torque and engine speed, and then the interval algorithm is adopted to transform the search of least fuel consumption value into the seeking of optimal interval to avoid the shifting busyness caused by the sudden change of the data of fuel consumption rate. The model of gear shifting indication strategy is established in Matlab/Simulink. Gear shifting tolerance is defined and its influence on gear shifting frequency and fuel consumption of vehicle is simulated and analyzed in the WLTP circle. The simulation results show that compared with the existing economical gear shifting strategy, the proposed interval algorithm of gear shifting indication strategy can obviously reduce the frequency of shifting gears with the fuel consumption of vehicle not increasing. Finally, a gear shifting indicator is produced and several road tests are done with a truck to verify the saving of fuel consumption of the interval algorithm of gear shifting indication strategy. The test results show that the indication strategy reduces the fuel consumption of the truck by 5% in average.