【作者】 杨斌；

【导师】 王伟达；

【作者基本信息】 北京理工大学 ， 机械工程， 2016， 硕士

【摘要】 换挡品质控制是换挡过程控制中最关键的技术之一,它不仅关系到乘员的舒适性,也对操纵部件的寿命、整车经济性和排放有着重要的影响。本文以某重型矿用车辆液力机械自动变速器为研究对象,基于不同阶段的控制目标,研究了换挡品质分段最优控制策略,并通过硬件在环仿真试验进行了验证。首先根据实车试验及测绘数据对包括发动机、液力变矩器、变速装置及负载的整车动力传动系统进行了动力学建模,重点对电液换挡控制系统中的比例电磁阀、双边节流阀和离合器进行了仿真模型的搭建和特性分析,通过台架进行了标定试验,得到比例电磁阀油压—电流响应和双边节流阀先导压力—输出油压的关系曲线,验证了所搭建模型的准确性,为研究换挡品质控制策略和硬件在环试验奠定了基础。然后在矿用重型车辆使用特点基础上提出研究对象的换挡品质需求,利用行星排特性关系式和Lagrange方程对换挡过程进行了运动学和动力学分析,得到了换挡各阶段冲击度和转矩的表达式,确定了两相过渡阶段离合器理想搭接时充放油离合器的转矩关系,据此分别提出了转矩相、惯性相的控制目标。综合考虑冲击度和滑磨功,运用LQR最优控制理论制定了基于不同工作相的换挡品质分段最优控制策略,分别研究了转矩相转矩跟踪控制方法和惯性相状态调节控制方法并进行了仿真分析。针对如何选取性能泛函加权矩阵Q、R参数值问题,仿真分析了Q、R矩阵中各个分量参数值对结果的影响,并利用遗传算法进行了优化求解,减少人为试凑次数,保证了所选取加权矩阵值对应最优的控制性能。最后,利用dSPACE实时仿真系统和RapidECU控制器快速原型,结合现有的电液换挡二级调压回路试验台架,搭建了硬件在环仿真试验平台。对控制策略进行了验证,结果表明该分段最优控制策略能够取得良好的换挡品质。更多还原

【Abstract】 Shift quality control is one of the most important technologies in shift process control.It is not only related to the comfort of passengers,but also has an important influence on the sevice life of components,fuel economy and emissions.Based on a hydraulic mechanical automatic transmission of heavy mining vehicles,a new phased optimal control strategy of gear shift quality was presented according to different control objectives of different stages of shifting.The proposed method was verified in hardware in the loop simulation(HILS).Firstly,the powertrain system models including engine,torque converter,transmission and load were built according to the test and survey data.The flow,pressure and dynamic characteristics of electronic-hydraulic system were studied before setting up the simulation modules.Then the P-I curve of proportional pressure control solenoid and the In-Out pressure curve of pressure regulation spool valve were obtained based on bench test,which calibrated the simulation models and laid the foundation for the study of gear shift quality control strategy and hardware in-loop test.Then,the shift quality requirements of heavy mining vehicles were presented according to applied characteristics.The kinematic and dynamic relationships of shift process were analyzed by using the planetary gear train equation and the Lagrange equation and the expressions of jerk of torque phase and inertial phase were obtained.Then the quantitative relationship of torque of cluches under the ideal alternating sequence conditions were proposed.Afterwards,the control objectives of torque phase and inertial phase were proposed respectively according to the analysis above.Taking jerk and slipping loss into comprehensive consideration,the phased optimal control strategy of gear shift quality based on different shifting stages was developed according to LQR optimal control theory.The torque tracking control method of torque phase and the state regulation control method of intertial phase were respectively studied and simulated.In order to solve the problem of how to choose parameter values of performance functional weight matrix Q、R,the genetic algorithm is used to optimize the calculation,which reduced the number of manual attempts and ensured the optimal control performance of the selected weight matrix.In the end,combining with the existing electro-hydraulic two-stage voltage regulator test bench,the control strategy was validated by using dSPACE real-time simulation system and RapidECU rapid control prototype,the hardware-in-the-loop simulation test platform was set up and the influence of vehicle quality or mine ramps on shift quality was studied.The results showed that the optimal control strategy can achieve good shift quality.更多还原