Abstract:Due to their dense gears or field load fluctuations, traditional tractors often need cyclic shifts, which affects the quality of work. Therefore, the adaptive shift control strategy is proposed for different field working conditions. Overshifting is avoided by skipping in start or acceleration conditions; when the load fluctuation is small, the fuzzy-PID control is used to meet the speed requirement; when the load fluctuation is large, the speed requirement is met by correcting the shift law. The strategy was verified by the MATLAB/Simulink simulation platform and the results show that the modified shifting schedule can avoid too fast shift frequency, reduce the speed fluctuation, thereby improving the fuel economy.