【作者】 刘振军；

【导师】 秦大同；

【作者基本信息】 重庆大学 ， 机械设计及理论， 2005， 博士

【摘要】 电控机械式自动变速(AMT-Automated Mechanical Transmission)是近年来发展起来的一种新型自动变速技术,在世界各国受到了广泛的关注。AMT与目前车辆普遍采用的液力自动变速传动相比,具有传动效率高、制造成本低的优点,其生产可沿用已有手动变速器的生产线,设备投资小,产品性能价格比高,非常适合我国汽车工业的发展现实,具有很好的产业化前景和广阔的应用范围。尽管国内外在AMT技术方面已进行了大量的研究,并且在国外已实现了产品化,但由于AMT自身的特性和技术的复杂性,在车辆起步和换档过程中对复杂多变的环境条件和不同驾驶意图的自动适应能力以及系统稳定性和可靠性等关键技术方面,还存在着较多的问题。针对AMT存在的关键技术问题,本文进行了深入系统的理论和试验研究工作。首先构建了人-车-路闭环系统,行驶的车辆是一个由驾驶员-车辆-道路环境构成的闭环系统,车辆的运行性能受到驾驶员、车辆状况和行驶环境的共同影响。驾驶员作为车辆操纵的主体,其行为特性直接影响到车辆的行驶性能,行驶环境变化决定了采用的控制策略的不同,根据这些需求,分析了驾驶行为特征、驾驶意图、道路环境条件的识别方法和车辆运行参数与控制信号的采集与处理方法,为实现基于人-车-路闭环系统的智能控制奠定了基础。　起步过程中的离合器控制是AMT系统的关键和难点之一。离合器控制受负载条件、道路条件、气候条件、车辆磨损状况及驾驶员意图等诸多因素的影响,同时控制目标不但需要满足车辆的平顺性要求,还要满足减少离合器滑磨,延长离合器使用寿命的目标。平顺性和离合器磨损是两个矛盾的指标,如何使这两个指标都能达到令人满意的效果是AMT车辆起步过程中离合器控制的关键。针对目前离合器接合控制策略存在的问题,提出了局部恒转速控制原则,通过对离合器的接合速度、结合量和发动机转速的协调控制,保证车辆具有良好的起步性能。由于车辆使用过程中机械系统的磨损,会导致车辆性能参数的变化,在对影响因素分析的基础上,制定了基于各种参数变化条件下的补偿控制策略。通过对换档品质及其评价标准、换档过程的分析,找出了影响换档品质的主要因素,从换档平顺性和快捷性两个方面分析了保证换档品质的控制措施;对换档过程中的离合器控制进行了研究,制定了离合器分离结合控制策略;在分析不同的道路条件和驾驶员意图以及车辆运行特征的基础上,根据道路条件和驾驶意图对车辆运行工况进行了划分,通过对最佳动力性换档规律的修正,制定了满足各种条件的换档控制策略,并对部分特殊运行工况的换档规律进行了仿真分析;更多还原

【Abstract】 The automated mechanical transmission (AMT) is a newly developing automatic transmission technology and catches researcher’attention in many countries. The AMT is more efficient and has a lower cost than traditional automatic transmission (AT). The automated mechanical transmission which has a high performance and low price can be manufactured by manual transmission product line with low equipment investment. It is the automatic transmission which fits the reality of development of automobile industry in China and has broad prospects of manufacture and wide applications. Although a good deal of study has been done on AMT there are still many problems due to the characteristic of AMT and complexity of technology. These problems such as automatic adaptive faculty to complicated and volatile environment and different driving intent during start up and shift, system stability and reliability have been studied in depth both in theory and experiment. A driver-vehicle-road closed loop system is constructed. In this system the performance of vehicle influenced by driver, vehicle conditions and environments. Driver is the main input of vehicle and his behavior immediately affect the running characteristic of vehicle; control strategies are varied with environments. According to these requirements recognition methods for drive intent and road condition are analyzed. Data acquisition and processing technique are also discussed. All of these laid the groundwork for intelligent control of driver-vehicle-road system. The control of clutch during start up is one of the most important and difficult point for AMT control. Many factors such as load, road conditions, weather, wear of vehicle and drive intent all affect the control quality of clutch. And meanwhile the vehicle must meet the requirements of ride performance and clutch wear. How to satisfy the two inconsistent targets is the key point of clutch control. The partial steady engine speed control is put forward aim at the defects of present clutch control. High start up performance is guaranteed by coordinating and controlling the engage speed and displacement of clutch and engine rotary speed. Compensatory control strategies are also designed base on the study of relationship between mechanical wear and vehicle parameters. Main modifying factors of shift quality are found out through analyzing the shift quality criterion and shift process. Control measures are brought forward base on smooth and quick shift. The action of clutch during shift is studied and control strategies for clutch engaging and disengaging are designed. Vehicle running conditions are classified according to all kinds of road conditions, drive intentions and running characters. Shift rules which can satisfy all conditions are designed on the basis of the modification of power shift rules and shift rules for some special conditions are also simulated. the concept of intelligent integrate shift system is set up and gear decision method under complex coupling conditions is put forward. Shift, start up and ride performance will be improved and clutch life will be prolonged if engine speed is well controlled according to control strategy and car dynamics. Electric throttle is used in AMT system. Engine speed can be well controlled during start up and shift by controlling electric throttle opening. Development of AMT system is carried out. Actuator of automatic electric clutch and shift are also developed. This kind of Actuator is simple in construction, low in cost and reliable in working. Its performance achieves the anticipated result. DSP control unit of AMT is developed; test bench of AMT system is built up and test cars of AMT is also developed. Testing under different work conditions has been done both on bench and cars. The results indicate that this AMT and its control system have a good performance. The driver-vehicle-road intelligent control theory is verified in practice.更多还原