搭载机电控制无级变速器混合动力汽车模式切换仿真分析

通过分析机电控制无级变速器(electrical-mechanical continuously variable transmission,EM-CVT)的结构特点,提出了搭载EM-CVT混合动力汽车的传动方案,建立了动力源数值模型、EM-CVT模型,分析了混合动力系统工作模式,并针对模式切换时的冲击问题,以减小冲击度为目标,通过分析典型工况下动力源输出转矩特性和各部件的动态特性,提出了基于发动机、ISG电机、自动离合器以及EM-CVT相互协调控制策略。利用MATLAB/SIMULINK仿真平台建立混合动力传动系统动力学模型,并对典型的模式切换过程进行了仿真分析。结果表明,所提出的控制策略能够有效控制混合动力传动系统在模式切换时产生的冲击,提高了混合动力汽车的驾驶舒适性。     

人在环路模拟驾驶仿真实验系统研发

汽车是人机协同控制的复杂系统,基于NI PXIe8108实时控制器、PXI7842R数据采集卡、模拟驾驶输入设备及相关软硬件搭建了驾驶模拟仿真系统;用LabVIEW编程语言建立了车辆动力学模型;用虚拟引擎Unity3D软件开发了视景系统;并通过数据库技术使仿真过程与视景系统相结合,实现仿真过程与三维动画实时视景系统的数据交互。结果表明：通过人在环路模拟驾驶仿真实验,使仿真过程中引入了驾驶模拟操纵,实现了人在环路的人机交互式仿真,得到汽车相关性能仿真结果,为驾驶过程中人和汽车协同控制仿真和极端工况下的仿真,提供了一种安全、可靠的人车协同控制仿真环境。     

正确适用拖拉机离合器的方法

1.科学冲击起步陷车时,要正确使用差速器、差速锁,不要用猛抬离合器踏板的方法冲击起步。2.迅速切断动力离合器踏板要一次踩到底,接合动力要柔和而不拖延。松抬离合器踏板的全行程一般是＂快-慢-快＂的抬脚过程。     

酥饼烤制温度的控制模型及仿真分析

金华酥饼有着千年历史,以传统的烤炉制作为主。基于现阶段酥饼生产中"烤"无法用现代技术替代,如果能将传统炉的温度控制复制到现代炉,将解决酥饼烤制的关键问题。通过对传统炉烤过程中的空气温度和炉壁温度的实测,建立烤制温度模型,利用PID控制方法,用MATLAB工具,在SIMULINK环境下进行仿真试验,经过计算和调整温度传递函数参数,得到适用于电烤温度控制的仿真曲线,为酥饼烤制的实质性研究提供条件。     

农机操作常见7误区

1.起步猛抬离合器机车起步时应缓慢地松开离合器踏板,同时适当加大油门行驶,否则,易造成对离合器总成及传动件的冲击,甚至损坏。2.长期脚踏离合器踏板有些机手在机车行驶中习惯将脚踏在离合器踏板上,其害处是:在高低不平的路面上行驶时,机车随之振动,这样会使离合器处于半结合状态,影响发动机功率传递,加剧离合器摩擦片磨损。     

渐变刚度钢板弹簧建模方法对比

为更好地分析钢板弹簧刚度特性,对钢板弹簧建模方法进行了对比研究。依据钢板弹簧国家标准GB/T 19844-2005,针对某型渐变刚度钢板弹簧分别在有限元软件Hypermesh和多体动力学软件Adams中建立其有限元模型和离散梁模型,并进行了仿真,得到刚度特性。将仿真结果与试验值进行了比较。结果表明,在针对该钢板弹簧的刚度分析中,运用离散梁法得到的刚度特性更加接近试验值。     

基于系统动力学的生鲜农产品物流库存仿真分析

为了分析各因素对生鲜农产品物流库存的影响,运用系统动力学方法,建立生鲜农产品物流库存系统流程图,并利用Vensim软件进行模拟仿真,最终得出:订货提前期延长、缺货率增大,会增加企业成本,消费需求减少,企业库存将大幅降低。因此,企业应准确掌握市场消费需求,确定合适的订货提前期及缺货率以控制成本。同时,供应链上、下游节点企业间需要加强合作,促进信息共享,以提高供应链整体绩效。     

基于SPC的乳制品加工环节质量安全控制研究

考虑到国内乳制品质量安全的现状,针对其质量安全问题,对乳制品加工过程进行分析。以巴氏杀菌乳为例,采取125个样本作为原始数据,将菌落总数作为控制对象,利用统计过程控制方法(简称SPC)进行计算和分析,通过建立控制图对加工过程质量安全实时控制,进而降低风险,保证乳制品的质量。     

虚拟样机技术在化工设备开发中的应用

本文简述了目前化工设备开发所使用的传统方法,指出了其弊端和引入虚拟样机技术的必要性。结合运用SoldWorks、ANSYS、ADAMS软件对化工设备产品进行三维造型设计、有限元分析、性能测试、联合仿真优化等,展示了虚拟样机技术在化工设备开发中的具体应用。采用此技术可缩短产品开发周期、降低生产成本、提高产品质量。     

插电式混合动力汽车纯电动行进间启动发动机的平顺性控制

针对单电机插电式混合动力汽车在纯电动行进间电动机启动发动机时由于系统输出转矩变化进而引起整车冲击的问题,分析得到发动机点火时刻的不同及离合器接合状态的不同是造成转矩波动的原因。在此基础上,提出了基于离合器主、从动盘转速差和电机角加速度为输入量的离合器压力模糊控制的混合动力汽车模式切换动态协调控制策略,并对比了发动机目标转速点火和怠速转速点火的控制效果。最后通过台架试验以及实车道路试验对提出的控制策略进行了验证。结果表明,基于目标转速点火的协调控制策略能减小整车的冲击度。     

Shifting control and simulation of wet dual clutch transmission

The dynamic model of the shift process of wet dual clutch transmission (DCT) is set up. Aiming at the characteristics of wet dual clutch transmission, such as being highly nonlinear and difficult to establish its math model, etc., a multiple rule weighting factor fuzzy controller is designed. Then the control scheme of shift process is built, which completes the transfer of engine torque through a combination of a manipulation of engine control and clutch pressure. Dynamic simulation model of wet DCT power train is implemented by using Matlab/Simulink software, the control scheme of shift process is simulated based on this dynamic model. The simulation results show that the control scheme can meet the needs of DCT shift process, and the tracking performance of controller is good. Finally, influencing factors of transmission shift control is discussed.     

Analysis of shifting control for dry dual clutch system

Aiming at the dry Dual Clutch Transmission (DCT) system, the motor driven dry dual clutch actuator is studied; the characteristic of distortion load for diaphragm spring and the dynamic transient process of the clutch are analyzed. The mathematical model is established for the system using fuzzy control and PI (Proportion Integration) control, and the simulation is carried out for the DCT shifting process. Simulation results indicate that the motor driven dry dual clutch system can meet the need of the shifting process control requirements and guarantee the high performance of DCT system.     

Modeling and control system simulation of automobile DCT

In order to reduce development time and cost of dual clutch automated mechanical transmission(DCT) control system,the dynamic model of automobile DCT control system is established by Matlab/SimDriveLine and the engine model is improved by neural network.Based on Matlab/Simulink,the simulation models of DCT control during starting phase,shift phase and shift rule are set up,and then the whole system of DCT is simulated.The simulation result indicates that the DCT system dynamic model and the designed controller are reasonable and feasible,and proofs that the model is suitable for developing DCT control system and improves the design efficiency of DCT system.     

Analysis on the influence of friction coefficient on the starting control of automatic mechanical transmission

Based on the fact that friction coefficient changes with the friction surface temperature,the influence of friction coefficient on automatic mechanical transmission (AMT) is studied during repeated starting process. A model is established for the transmitted torque of clutch and the temperature rise on clutch plate surface during AMT starting. Based on the launching control rule of “fast-slow-fast”,the repeated starting for AMT and the friction work of the friction pair are simulated. The simulation results show that friction coefficient changes with the change of the friction work. After several starting,friction coefficient and the transmitted torque of clutch diminish a lot,and the slipping between drive plate and clutch plate always exist, therefore,the vehicle can’t start.     

Performance and Slip Control of Torque Converter Lock-up Clutch

The application of lock-up clutch slip control balances the fuel economy and drivability, and greatly improves the performance of hydraulic automatic transmission. The structure of the lock-up clutch and the friction material of lock-up clutch lining are discussed, a detailed research on varying characteristic due to engaging time during the lock-up clutch engagement is developed, too. By applying the slip control, lower fuel consumption is achieved.     

Clutch Control for Automotive Start-up Process

The conventional driveline with manual gearbox and dry clutch can be retro-fitted to manipulate automatically,so that the electo-mechanical components or the Automated Mechanical Transmission has been obtained.The clutch engagement position for automotive start-up process can be controlled by the fast-low-fast speed.How to control the clutch engagement during the slipping stage is the key to clutch control.The mostly influent factors of the clutch engagement during start-up process have been analysed thoroughly from the practical point of view.The strategy of clutch control has been proposed on the principle of lessening the start-up jerk and the friction work.It is successfully applied to Santana model,which can be proved by the road test of the vehicle on the slope.     

Analysis of oil pressure distribution influenced by channel flow structure of wet friction clutch

When multi disk clutch is in disengaged operation, friction plates and mating plates may not separate absolutely. To avoid the slipping friction caused by this and reduce the clutch’s overheating, the lubricant pressure between the plates should be well distributed in design. With the use of ANSYS/FLOTRAN software, 3 D finite element models of six different channel flow structures are established. Using finite element method and the fluid dynamic theory, the flow field is analyzed, and then the law of the influence of different channel flow structures on oil pressure distribution between the plates is summarized. The result of the study shows that the four squirt holes at right side with perforated structure are better than those without, and squirt holes with the cone or stepped shape are better than those with column shape, which means that with the two improvements of the channel flow structure, the lubricant pressure distribution can be uniformed.     

Simulation and Analysis of the Dual-Clutch Transmission Starting Control

With unique configuration characteristic,dual-clutch transmission(DCT)overcomes the shortcoming of power interruption when shifting in traditional AMT,which results in good power performance,fuel economy and driving comfort,and recently it becomes a new development trend in the field of transmission.Basing on the analysis of starting control principle of DCT,control principle and method that both the dual clutch engaged in the starting process simultaneously with engine constant speed are proposed.And the starting characteristic of the dry dual-clutch transmission is simulated and analyzed,providing theory foundation for the development and research of the dual-clutch transmission.     

Analysis on starting characteristic of continuously variable transmission system with reflux power

Considering on the characteristics of the transmission system and some key units of continuously variable transmission system with reflux power, a dynamic simulation model and a control strategy are established. The design method of the new continuously variable transmission system is verified by simulation. The simulation result on this continuously variable transmission system shows that the rotating speed of the driven plate can rise up rapidly during starting clutch engagement, and the sliding friction power is lower than 3 kJ which is nearly equal to one third of the friction power of the traditional vehicle.