| With the gradual promotion of consumers’ purchasing power, consumers havemore and more high requirements of vehicle safety, comfort and driving performance.Therefore, the automatic transmission in the car is used more widely. Among them,Automated Mechanical Transmission is one of the automatic transmission types whichare widely used in the car market today. It comes from Europe. It is usually based onmanual transmission by adding actuators to realize the automatic control of shifting gearand clutch. Compared with other types of transmission, it has the advantages of hightransmission efficiency, driving feel closer to manual driving pleasure, low cost,economy, simple structure, and the pare parts are general with the manual transmission.And the effect is obvious of the engine idle start stop system in energy saving andemission reduction. It has the advantages of high safety, easy realization and low cost. Ithas been widely used in domestic and abroad, it may also become a standardconfiguration in future. But the research of idle start stop system and AMT matchingtogether technology will bring some difficulties to the power transmission systemcontrol. Especially when the vehicle at the start of the engine starts automatic controlclutch starting process, in the coordinated control between the engine control systemand the AMT control system, there are a lot of problems that should be solved in ridecomfort, economy and reliability.In this thesis, aiming at several key technical problems of idle start stop systemexisting AMT control technology, combined with the project of "idle start stop system,AMT transmission product development" of the technical center of FAW, it is in-depthresearched on the idle start stop system, AMT automatic clutch control and law, and itwill be verified by the experiment. The main work is as follows.1. Summary on automatic transmission and idle stop systemSeveral common automatic transmissions are introduced in the vehicle market atthe present: hydraulic automatic transmission, mechanical steeples speed transmission,dual clutch automatic transmission, automatic mechanical transmission. The workingprinciple and the structure characteristics of these kinds of transmission are described.Finally, mechanical type automatic transmission AMT is selected as the mainconfiguration of the future development of economic type of car. At the same time, thenecessity and the development status of configuration engine idle start stop system are briefly introduced.2. Research and design of AMT system start stop system idleBy analyzing the principle and characteristics of start stop three design schemes ofthe idle speed, separation type motor starting mode is selected the final technical routefor idle start stop system. Comparison between idle start stop system and the traditionalvehicle, the general structure of idle start stop system is illustrated. In order to make thecoordinated control between the engine and the AMT, it also needs to research the idlecontrol strategy of engine start stop system, including the work process of engineautomatic start and stop, trigger conditions of stop and start machine. And theestablishment of AMT system implementation scheme of mechanism, AMT controlsystem, the principle and structure of the transmission control unit TCU hardware andcontrol software are posed.3. Automatic clutch control strategyFirst of all, the function of a clutch and structure characteristics of different typesof clutch are introduced. It includes the working principle of self adjusting clutch, alsodescribes the separation characteristics of clutch parameters. Through the analysis of theall stages in the process of the clutch engagement, the coordination control method ofstarting and idle stop system is determined. Analysis on two indicators of clutch control(jerk and friction work), the analysis results of dynamic starting process, to providetheoretical basis for the research on clutch control strategy of the target engine speedclosed loop. In order to ensure the safety of the AMT system, to avoid frequent startcausing the clutch ablation, the research is made on the estimation method of the dryclutch temperature.4. Test researchTest is one of the most important links in the process of product development. Onlythrough the test to prove the control function of the whole system is realized and theperformance meets the requirements. First of all, through the control performance benchtest of clutch actuator. Then, through the estimation precision of bench test of clutchtemperature model. Finally, idle start stop system after crawling through vehicle testsverify the matching, start function and performance. The test results show that, theresearch on matching idle start stop system of clutch control strategy achieves thedesired effect. |
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