Design and Optimization of the Shift Schedule and Gear Ratios for a Two-speed Pure Electric Logistics Vehicle

Based on a pure electric logistics vehicle with a single reducer, the paper matches a new electric motor, takes the electricity consumption in NEDC working condition as the optimization objective, designs the two-speed transmission gear ratios to replace the fixed gear ratio and gives a new shift schedule matching the electric motor. Then, the two gear ratios are optimized according to the new shift schedule. The optimization results indicate that the electricity consumption(Kwh/100km) in NEDC working condition decreased by 1.21%. The maximum motor working rotation speed decreased by 44%. The maximum inclination increased by 11.68%. The acceleration time of 0~50km/h is the same as single reducer vehicle, which can meets the requirements. Compare with the single reducer, the two-speed transmission has a better performance.