Research on Integrated Shift Control Strategy for Automatic Transmission

2016 ◽  
Vol 835 ◽  
pp. 687-692 ◽  
Author(s):  
Lin Yue Zhang ◽  
Yao Fu ◽  
Xing Zhong Li

Shift process of automatic transmission is divided into torque phases and inertia phase, and the control principle of clutch to clutch shift is studied with the lever method. Then, inertia phase engine and transmission integrated control principle and entire shift process engine and transmission integrated control principle are respectively studied with taking power on up shift as study example and taking the transmission output torque fluctuations during shifting minimum as control target. Simulation results are compared to the results of power on up shift without engine and transmission integrated control, and it is proved that the transmission output torque overshoot peak with inertia phase engine and transmission integrated control strategy is decreased significantly and shifting jerks are reduced. Shift quality is improved significantly.

2014 ◽  
Vol 643 ◽  
pp. 42-47 ◽  
Author(s):  
Yan Xiao Fu ◽  
Liang Yi Cui ◽  
Xiang Yang Xu ◽  
Peng Dong

Basing on the fact that requirements for shift quality in automatic transmissions have been increasing rapidly necessitates the establishment of a suitable shifting control strategy in order to facilitate smoothness of different processes, this paper introduces a simulation model of an 8-speed automatic transmission for front-drive vehicles with respect to detailed shifting strategies and relative parameters. The transmitted torque of the oncoming shift elements before synchronization point can be reduced by an impact function in order to damp the impact and thus make the gear shifting process more smooth. This paper makes a systematic introduction of the structure of 8AT, theoretical basis of control strategy, the establishment of the simulation model and the comparison between test results and simulation results. The conclusion shows that with an accurate dynamic model, simulation results and test results are neighborhood data, the simulation model can be used to help realizing the ultimate goal of better shift quality with higher efficiency, lower shift loads and improved shifting comfort.


2015 ◽  
Author(s):  
Qingkai Wei ◽  
Yulong Lei ◽  
Xingzhong Li ◽  
Boqin Hu ◽  
Zhengwei Liu ◽  
...  

2011 ◽  
Vol 48-49 ◽  
pp. 1038-1043
Author(s):  
Yan Wei Liu ◽  
Ke Gang Zhao ◽  
Xiang Dong Huang ◽  
Rong Shan Yang

Working principle of an uninterrupted shift transmission (UST) based on overrunning mechanism and its driveline dynamic model, as well as shift control strategy are studied. For shift quality optimization, the throttle control parameters are calculated based on simplex method and genetic algorithm. Using the control strategy and optimized parameters, simulation results show that jerks and clutch slip during shift are controlled well, satisfactory shift quality is obtained without power flow interruption.


Author(s):  
Jeongman Park ◽  
Sunghyun Ahn ◽  
Oheun Kwon ◽  
Youngho Jun ◽  
Minhyo Kim ◽  
...  

In this paper, a 2 stage continuously variable transmission (CVT) shift control algorithm is proposed for the 1–2 upshift of the planetary gear to achieve the shift quality. A fuzzy control algorithm is designed considering the relatively slower response characteristics of CVT. In order to evaluate the performance of the control algorithm, a 2 stage CVT vehicle simulator is developed including a dynamic model of the CVT powertrain. From the simulation results, it is found that CVT gear ratio changes faster in the inertia phase and remains constant after the inertia phase of the planetary gear shift, which provides the reduced torque variation by the proposed control algorithm.


2021 ◽  
Vol 37 (4) ◽  
pp. 677-689
Author(s):  
Guang Xia ◽  
Yueqiang Wang ◽  
Xiwen Tang ◽  
Linfeng Zhao ◽  
Jinfang Hu

Highlights A power shift control strategy based on torque and speed transition, which aims to deliver multiple target and multiparameter optimization of power shift control, is proposed in this study. It can effectively solve the shift power cycle. Based on minimum optimal control theory, the optimal control of shift quality during power shifting optimizes clutch terminal oil pressure, which is determined by solving the Rebecca differential matrix equation and shift characteristics based on various stages. By aiming at the multiple target and multiparameter optimization problem of the clutch control in the power shift process, the minimum optimal control principle is applied to the shift quality optimization of the power shift. Based on the minimum optimal control theory, the optimal solution of the terminal oil pressure of the clutch is determined by solving the Rebecca differential matrix equation to improve the shift quality of the power shift process. Abstract . The dual clutch of the combined transmission of a tractor with large horsepower uses a dynamic shifting process, in which only one clutch undergoes slipping friction during the shift. A power shift control strategy based on torque and speed transition, which aims to deliver multiple target and multiparameter optimization of power shift control, is proposed in this study. Based on minimum optimal control theory, the optimal control of shift quality during power shifting optimizes clutch terminal oil pressure, which is determined by solving the Rebecca differential matrix equation and shift characteristics based on various stages. In addition, the power shift simulation model of the double clutch is established. Simulation results show that the power shift control strategy based on single slip friction can effectively avoid power flow cycle, uninterruptible tractor power shift, and adaptive resistance change. The minimum optimization theory can effectively reduce the output torque fluctuation in the dynamic shift process, reduce friction work, and improve the shift impact. Keywords: Double clutch, Heavy-horsepower tractor, Minimum theory, Power shift.


2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Yilin He ◽  
Jian Ma ◽  
Xuan Zhao ◽  
Ruoyang Song ◽  
Xiaodong Liu ◽  
...  

Aiming at improving the tracking stability performance for intelligent electric vehicles, a novel stability coordinated control strategy based on preview characteristics is proposed in this paper. Firstly, the traditional stability control target is introduced with the two degrees of freedom model, which is realized by the sliding mode control strategy. Secondly, an auxiliary control target further amending the former one with the innovation formulation of the preview characteristics is established. At last, a multiple purpose Vague set leverages the contribution of the traditional target and the auxiliary preview target in various vehicle states. The proposed coordinated control strategy is analyzed on the MATLAB/CarSim simulation platform and verified on an intelligent electric vehicle established with A&D5435 rapid prototyping experiment platform. Simulation and experimental results indicate that the proposed control strategy based on preview characteristics can effectively improve the tracking stability performance of intelligent electric vehicles. In the double lane change simulation, the peak value of sideslip angle, yaw rate, and lateral acceleration of the vehicle is reduced by 13.2%, 11.4%, and 8.9% compared with traditional control strategy. The average deviations between the experimental and simulation results of yaw rate, lateral acceleration, and steering wheel angle are less than 10% at different speeds, which demonstrates the consistency between the experimental and the simulation results.


2013 ◽  
Vol 791-793 ◽  
pp. 668-671
Author(s):  
Ke Gang Zhao ◽  
Hao Chang ◽  
Yong Liang Hu ◽  
Wei Hao Yao

Uninterrupted Shift Transmission (UST) is a novel vehicle transmission and which is introduced as the research object in this paper. It realizes torque uninterrupted shift by controlling dual multimode controlled shifter (MCS) modes and synchronizers. Fuzzy control technology is adopted in shift control strategy in order to improve its shift quality. Experimental results show that the fuzzy control strategy can improve the shift quality of UST effectively.


2013 ◽  
Vol 455 ◽  
pp. 376-382 ◽  
Author(s):  
Yang Liu ◽  
Shu Han Wang ◽  
Xi Lu ◽  
Ting Bin Song ◽  
Wen Shu Wei ◽  
...  

For the development research for a new 8 step speed automatic transmission, a simplified dynamic model for this transmission was established. Aimed at four basic shift types, the ideal characteristics of shift clutch and engine control were set up. By using torque estimation method, PI slip control algorithm and engine coordinated control principle, the control model were developed for two main shift phases which are torque phase and inertia phase. The test on the rig and vehicle verified the accuracy and feasibility of this shift control strategy. The development model and algorithm have a high value for engineering application.


2015 ◽  
Vol 2015 ◽  
pp. 1-11
Author(s):  
Shujun Yang ◽  
Yong Bao ◽  
Xianzhi Tang ◽  
Xiaojuan Jiao ◽  
Deqing Yang ◽  
...  

A hydromechanical variable transmission (HMT) has advantages of continuous variation and high efficiency. So it is one of the ideal transmissions of heavy vehicles. The continuous speed varying process involves speed governing in range and range shift. Integrated control strategy of the HMT is proposed in this paper. The algorithm of the asymmetric saturated incremental proportional integral derivative (PID) speed control strategy in range and range shift conditions are derived. And this paper presents the range shift logic and range shift control strategies. A controller model is built in Matlab Simulink and cosimulated with the model of vehicle equipped with a two-range HMT. The HMT prototype hardware-in-the-loop simulation (HILS) platform of the integrated control strategy is built. The HILS results show that the range shift process is smooth and speed fluctuation does not happen. In the throttle stable stage, the engine speed is adjusted to the near optimal speed, and its change rules are in accordance with simulation results. The integrated control strategy is reasonable.


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