Optimization of Clutchless AMT Shift Control Strategy for Electric Vehicles.

With the development of the economy, the number of cars in China is rapidly expanding, which has caused a certain degree of pollution to the environment. The emergence of electric vehicles has the good evasive effect on this issue. In order to shorten the shifting time of the electric clutchless automatic mechanical transmission (AMT) and reduce the shifting shock, the DC brushless drive motor, the clutchless and synchronizer-free AMT and the final drive are combined to establish the electric vehicle power transmission model of the drive motor and AMT controlled by the power transmission integrated controller. And the dynamic analysis of the picking phase, the shift process, and the torque reduction and torque recovery phases are carried out. Based on the dynamics of the shifting process, the implementation flow of the coordinated control of the shifting process is created. The classical PD control algorithm is used to optimize its control strategy and realize the optimal shift control of the clutchless AMT of electric vehicles. The experimental results show that the electric vehicle with the shift control strategy has a shifting time of 720 ms-750 ms in the static, low speed, medium speed and high speed state, and the impact degree is inside ±10 m·s-3 during the shifting process. This shows that the electric vehicle using the proposed shift control strategy has less time for shifting, high shifting quality, and smooth shifting process. [ABSTRACT FROM AUTHOR]