Gearshift Dynamics Simulation In Two Speeds AMT Of Pure Electric Vehicle

As an important part of new energy vehicles, pure electric vehicle (PEV) iscalled more and more attention by the country and the whole plant and is one ofchina’s seven strategic emerging industries. Pure electric vehicle using thetransmission play a significant role in increasing the overall performance of thevehicle. The motor’s operation curve has obvious advantages for the traditionalengine, for its operation characteristics of low speed but high torque at the begainand high speed but constant power motor, which can match well and make the motorwork in high efficiency range, therefore, for pure electric automobiles, manytransmission gears is completely unnecessary. However, employing the fixed gearreducer separately put forward higher requirements for motor performance, so thepaper puts forward the two speed automatic transmission (2AMT) research anddevelopment, the main contents are as follows:1) Analysis of the transmission structure of pure electric vehicles and make thecorresponding explanation to it, according to the vehicle power requirements,including the maximum vehicle speed, maximum gradability, accelerationperformance and so on matched and calculated the driving motor power and torqueand the speed ratio of2AMT.2) Analysis of the shifting process of pure electric vehicles,expounds theprinciple of the gear shift and propose a torque control method to improve thequality of the gear shift, on this basis, make an corresponding explanation to theeconomy shift curve and the dynamic shifting curve, what’s more, according to thecharacteristics of pure electric vehicles making and employing the two parameters ofeconomy shift curve.3) According to the vehicle driving characteristics developed the controller ofthe transmission shift motor, is the TCU. At the same time, analyzeed the hardwarecircuit and the function of the TCU implementation and according to the TCUdeveloped its software control scheme. Finally, with these conditions correspondingformulate the CAN communication protocol and make it matched the vehicle CAN.4) Preparation of shift strategy in simulink and combined with the cruisesoftware platform to analysis the pure electric vehicle simulation and researched thedynamic process of the shift motor to judge the rationality of control strategy in this process. Finally, setting up the half vehicle test platform for2AMT prototype tomake fatigue bench test and the shift dynamic test, at the same time, analysis of theshift time, shift impact, shift noise and so on.