Double Clutch Transmission Control Quality Evaluation And Optimization

Double Clutch Transmission (DCT), with its excellent shift quality and high transmission efficiency has become the focus of automotive transmission technology research. Currently, most research is focused on DCT's starting control, shift control, and shift schedule formulated, however, on the control quality evaluation, and control optimization based on the evaluation are not much. Based on the current study situation of DCT, through the evaluation for quality control intend to guide the optimal control by evaluating the quality is a new idea on the product of the DCT and other type of automatic transmission, which has an important significance on the development of domestic automatic transmission industry and to improve the competitiveness of China's auto industry.There are six chapters in this paper that is the quality of control evaluation and optimization about independent development of the DCT system, which is come form the follow-up study on "863"high-tech program funded project (No.2006AA110110) "Research and Development of Car's Double Clutch Transmission ", Major scientific and technological about special issue of Jilin Province "the key technologies of DCT" and the research funded by National Natural Science Foundation of China (50505014) "Dynamic Vehicle Shift Quality Evaluation System. The work has two intention. On the one hand, provide a method to determine the control objectives and control methods of DCT and guidance and reference for the objective evaluation and calibration of DCT, on the other hand, optimize control strategy and control algorithm of the DCT system according to the control objectives.The first chapter is the introduction, which describes the background and the establishment of the questions, and summed up the current development of double-clutch transmission. Through the collation and analysis of the previous DCT's key technologies in the simulation control, quality control evaluation and optimization on published articles, essays, various patents and other research results points out this paper's main idea and the research line.The second chapter is the vehicle system modeling used in DCT's simulation which includes engine model, double clutch and control device models, transmission and synchronizer model, load model, the vehicle dynamics model, controller model (TCU), and driver model. Building a simulation mode in the Matlab/Simulink environment with the study sample of the electric dry dual clutch transmission vehicle, and also builds the off-line simulation platform which provide a method to determine the quality control for the follow-up evaluation and optimization.Chapter three is the objective quality control evaluation of DCT. According to the different driving conditions of vehicles equipped with DCT, from the view of control point subdivide the evaluation indices definition, design the quality control evaluation system and study the mapping between Quality Evaluation and Control. Used AHP to determine weights of the control quality indices, determine the control objectives through the co-simulation of vehicle system model and evaluation system, namely each of the evaluation of control expected range, which provides the optimal objective to optimize control strategy and control algorithm of double-clutch transmission.Chapter four is integrated control and optimization of DCT. Analyze the process of starting and shifting of DCT, applicate the fuzzy control strategy in the starting control, select the highest rate level of starting quality assessment as the objective function and optimize the clutch engagement speed and engine throttle which influences the quality of starting, then get the optimal solution set based on the fuzzy control rules, and also proposed a method of optimization of idle crawling quality.Select the highest level of shift quality evaluation as the object function, through the multi-objective genetic algorithm optimization method, optimize the torque phase and the inertia phase of timing switch relates to the clutch and the engine,then get the optimal solution set of the clutch separation and combination. Give the simulation result about starting quality and shift quality after the optimization which based on the vehicle model and evaluation system simulation platform of DCT. By comparing the simulation results verify the start/shift control strategy and control algorithm to optimize the program is correct, thus improving quality control of DCT. Finally, the optimization results applied to a dry double-clutch transmission, developed a system of integrated control strategy.Chapter five is experimental verification. In order to reduce the double-clutch transmission control system's development cycle, using dSPACE rapid control prototyping technology to build test-bed, and conducted a bench test in different conditions. The experiment results show the feasibility of control system's software, and hardware, and the correctness and effectiveness of the multi-level control algorithm and control strategies.Conduct a road test with the prototype, give the result of the prototype of the starting and shifting, before and after optimization of the test results show that quality control of the car has a good improvement by using the proposed optimized control strategy and control algorithm. In addition, use the prototype conduct a online evaluation of the quality control test, shows the shift quality evaluation on the car, compare the objective rating scale results and subjective ones, then demonstrate the feasibility of this method of online assessment.Chapter six summarizes the full text.The control theory and methods of evaluation about DCT of this paper can also provide some reference to AMT, AT, TC+AMT during their development. In addition, it provides a more complete verification platform to evaluate and optimize the control quality which is though the simulation, rapid prototyping and testing of the DCT during the development process.