【作者】 刘延伟；

【导师】 黄向东；

【作者基本信息】 华南理工大学 ， 车辆工程， 2012， 博士

【摘要】 无动力中断机械式自动变速器（UST-Uninterrupted Shift Transmission）是汽车自动变速器领域一种具有原始创新性和自主知识产权的新型传动方案。UST在吸收平行轴-齿轮成熟传动技术的基础上，采用以类似于可控超越离合器的多模可控换挡器（MCS-Multimode Controlled Shifter）为核心构建的双MCS总成替代双离合器变速器（DCT-DualClutch Transmission）中的双离合器总成，通过操纵双MCS工作模式与预挂挡装置（同步器）的合理组合和切换，使UST实现无动力传输中断的挡位切换，既克服了机械式自动变速器（AMT-Automated Manual Transmission）换挡时动力中断的缺点，又避免了液力式自动变速器（AT-Automatic Transmission）和DCT动力换挡时必须进行的复杂搭接控制。UST传动系统采用与AMT和DCT相似的基础结构，即保留相同或采用相似的拓扑布局、众多部件和总成。平行轴式齿轮传动在国内具有良好的技术基础和产业基础，因而UST具有技术和生产继承性好的特点。本文以新型无动力中断机械式自动变速器UST为研究对象，综合运用理论分析、建模仿真和实验研究等手段对其操作方法、换挡特性、传动系统控制策略和换挡品质的综合优化等进行了较深入和系统的研究，主要研究工作包括：从MCS工作原理及特性入手对UST具体技术方案进行研究，分析了双MCS总成的运动学特性，阐明了各种工况下基于MCS工作模式切换的UST换挡原理和操作方法。设计并研制了UST功能样机，搭建了UST功能验证实验平台，进行了UST的换挡功能试验。试验结果表明UST实现了方案所设计的换挡时动力传输不中断的功能。建立了基于试验测试数据的发动机动态转矩模型和MCS动态模型，搭建了包括发动机、离合器、变速器和整车动力学模型的UST整车传动系统动力学模型。基于发动机油耗实测数据和整车参数，设计了UST标准换挡规律和最佳经济性换挡规律。在Matlab/Simulink仿真软件平台上，搭建了UST整车仿真控制模型和平台仿真控制模型。通过仿真与试验结果的对比验证了UST系统动力学模型和仿真控制模型的正确性。应用UST整车仿真控制模型进行了UST换挡的整车实例仿真。针对换挡功能试验和UST整车实例仿真中所表现出的换挡冲击问题，深入分析了UST换挡过程中的独特动力学特性，并针对UST升、降挡冲击不同的产生原因，分别设计了UST专有的升、降挡控制策略，并分别应用于仿真模型和实验平台。通过对不同仿真及试验结果的对比分析，所设计的升、降挡控制策略对于解决UST换挡冲击问题的有效性得到了验证。提出了包括换挡平顺性评价指标和离合器磨损评价指标的UST换挡品质综合评价指标。针对UST升挡控制策略存在的仅考虑换挡平顺性的缺陷，提出了考虑通过在离合器滑磨过程中进行恰当的动力源输出转矩控制以减小离合器磨损的UST升挡优化控制策略。以换挡品质综合评价指标最优化为目标，应用智能优化方法求解了相关的控制参数。采用所提出的优化控制策略和求解得到的控制参数在UST实验平台上进行了升挡试验，试验结果验证了UST升挡优化控制策略和基于遗传算法的换挡参数优化方法的有效性。本文通过理论分析、建模仿真和实验研究穿插进行的方法，对UST的操作方法、动态换挡特性、换挡控制策略和换挡品质的综合优化进行了较深入和系统的研究。分析、仿真和试验结果具有较好的一致性，为下一步UST的产品开发和在整车上的应用提供了理论基础和技术指导。更多还原

【Abstract】 Uninterrupted shift transmission (UST) is a novel vehicle transmission concept withoriginal innovation and proprietary intellectual property rights. UST is based on the matureparallel shaft-gear technology, and replaces the dual clutch assembly in dual clutchtransmission (DCT) with the dual controllable one-way clutch based multimode controlledshifter (MCS) assembly. UST realizes torque uninterrupted shift by controlling dual MCSmodes and synchronizers. The shift process of UST not only overcomes the inhered torqueinterrupt drawback of automated manual transmission (AMT), but also avoids the preciseclutch-clutch overlapping control of both planetary-automatic transmission (AT) and DCT.Since UST has adopted the similar basic structure to AMT and DCT, which meanskeeping the same or adopting the similar layout, parts and assemblies. As a parallel shaft-geartransmission, UST owns the well technical and production basis.In this dissertation，the operating method, dynamic shift characteristics, shift controlstrategies and shift quality optimization of the novel transmission UST are deeply investigatedthrough theoretical, simulation and experimental means. The main research work is asfollows:Starting with the working principle and characteristics of MCS, the material technicalblue print of UST driveline is studied. The kinematic characteristics of dual MCS assemblyare analyzed. Based on the switch of MCS working modes, the UST shift principles andoperating methods of dual MCS for diversified vehicle working conditions are elucidated.UST functional prototype is developed, UST bench experiment system is constructedand UST shift functional experiments are carried out. The experiment results show that USThas realized the designed function of torque uninterrupted shift.The engine dynamic torque model has been established based on the experiment data,and MCS dynamic model has been established. The UST driveline system model includingdynamic models of engine, clutch, transmission and vehicle has been established. The shiftschedules for both the normal performance and fuel economy have been designed based onengine fuel map data and vehicle parameters. The simulation control model for UST vehicleshas been built up on Matlab/Simulink software, which provides foundation for theoretical analysis on UST shift characteristics and simulation study on UST vehicle performance. Thesimulation of UST vehicle performance has been carried out.Considering the shift shocks appeared in results of UST shift functional experiment andvehicle performance simulation, the idiographic dynamic characteristics of UST shift processare investigated. Aiming at different causes of UST upshift shocks and downshift shocks,UST upshift control strategy and downshift control strategy have been designed and appliedin the simulation model and the experiment system respectively. By the comparation andanalysis of the different simulation and experiment results, the designed UST upshift anddownshift control strategies have been validated effective to solve the shift shock problem.The estimating index of UST shift quality, which includes indexes of shift smoothnessand clutch abrasion, is proposed. Aiming at the weakness of UST upshift control strategy, theUST upshift optimized control strategy has been designed to reduce clutch abrasion by powersource assist in the clutch slipping process. For the optimization of UST shift qualityestimating index, the relative control parameters are solved by intelligent optimizationmethods. The proposed optimized control strategy and solved parameters are applied in USTexperiment system, and the validity of the strategy and parameters optimization methods havebeen demonstrated experimentally.Theoretical, simulation and experimental methods are all used in the dissertation toinvestigate the operating method, dynamic shift characteristics, shift control strategies andshift quality optimization of UST. The theoretical, simulation and experimental results arehighly agreeable with each other, which provides theoretical foundation and technicalguidance for UST product development and future application in vehicles.更多还原