动力换挡变速器液压换挡过程仿真与试验研究

Powershift transmission hydraulic shifting process simulation andexperimental study

为满足重型车辆换挡动力不中断、换挡平顺的需求,本文设计了重型车辆动力换挡变速器换挡控制系统,利用AMESim软件,从换挡液压系统出发,对变速器换挡模块进行搭建分析,考察了换挡过程中液压系统油压特性、整车车速、冲击度以及离合器C1/制动器C2滑摩功动态特性。仿真结果表明系统能够满足动力换挡的要求;此外,针对所设计的液压换挡系统进行了台架试验,对仿真和试验的结果进行对比,仿真结果表明:目标车速响应时间提前了2.67 s, C2油压响应时间提前0.09 s且切换时间减少了13%,C1油压响应滞后0.07 s且出现压力超调量;试验结果显示:油压稳定性较差且转矩曲线响应时间提前0.06 s,并且冲击度变化曲线振幅较大。试验结果与仿真结果基本一致,验证了仿真结果的准确性。

To meet the requirements of uninterrupted power shifting and smooth gear changes for heavy-duty vehicles,this paper designs a power-shift transmission control system.Utilizing AMESim software,the hydraulic shifting module of the transmission is analyzed,focusing on hydraulic system pressure characteristics,vehicle speed,impact force,and dynamic properties of clutch/brake friction.Simulation results demonstrate that the system meets the demands for power shifting.Additionally,a bench test was conducted to validate the designed hydraulic shifting system.In the comparison between simulation and experimentation,the target vehicle speed response time of the simulation result was advanced by 2.67 s,the C 2 oil pressure response time was advanced by 0.09 s with 13%reduction in shift time,while the C 1 oil pressure response was delayed by 0.07 s,exhibiting pressure overshoot.The test results indicated poor oil pressure stability,0.06 s advancement in torque curve response time,and a significant amplitude increase in the impact force curve.Despite these differences,the test results were generally consistent with the simulation results,confirming the accuracy of the simulation.