MINISTRY OF EDUCATION AND TRAINING HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION GRADUATION THESIS AUTOMOTIVE ENGINEERING TECHNOLOGY APPLY PID ALGORITHM ON CVT TO ENHANCE VEHICLE PERFORMANCE INSTRUCTOR: DUONG TUAN TUNG, Ph.D STUDENTS: DU THANH VINH NGUYEN HOANG TIEN SKL012552 Ho Chi Minh City, 2024 HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY OF INTERNATIONAL EDUCATION GRADUATION PROJECT APPLY PID ALGORITHM ON CVT TO ENHANCE VEHICLE PERFORMANCE DU THÀNH VINH Student ID: 20145020 NGUYỄN HOÀNG TIẾN Student ID: 20145440 Major: AUTOMOTIVE ENGINEERING Supervisor: DƯƠNG TUẤN TÙNG, PhD. Ho Chi Minh City, 2024 ACKNOWLEDGEMENT This Graduation Thesis Report of major Automotive Engineering Technology about “APPLY PID ALGORITHM ON CVT TO ENHANCE VEHICLE PERFORMANCE” is the achievement of our group in the research processing with the best dedication of teachers from Faculty Vehicles Energy Engineering in Ho Chi Minh University of Technology and Education. First and foremost, we could not have completed this dissertation without the support of our main supervisor Dr. Duong Tuan Tung, we want to show our special thanks to him for his valuable support and attention, which lead to complete our report in time.
Besides, we would like to express my sincere gratitude to Dr. Nguyen Manh Cuong, who had taught us the first lesson about Theory of Vehicle and MSc. Nguyen Trung Hieu for his Automation class. Furthermore, we would like to give the best thanks to our family for their wise counsel, sympathetic ear and stand by our side through the report process.
Sincerely! Ho Chi Minh City, January 08th, 2024 Group of Authors Du Thanh Vinh and Nguyen Hoang Tien i SUMMARY OF THE TOPIC In this day and age, most of Vehicle Manufacturers have had in a race on enhancing their own car, especially engine block. They try all ways to make the vehicle more power, faster and more wonderful but consume with a little fuel source for the economy. Thus, there exist so many scientists do research and experiment to find the best solution for efficient vehicle in this century. This project "APPLY PID ALGORITHM ON CVT TO ENHANCE VEHICLE PERFORMANCE" also contributes a little bit to research the efficiency of vehicle.
The dissertation has calculated, design, simulate and do experiment a vehicle system equipped with CVT and controlled by PID algorithm. Based on the mathematical equation, the controller was built to optimize the vehicle performance through any different kinds of cycle test data imported from the U. Department of Transportation, National Highway Traffic Safety Administration. The vehicle we use to do the research in this report is Honda Accord 2018 1.5L – which equipped CVT system on it.
Through the processing, we have found out the formula relate to the CVT system, PID algorithm and apply the parameters of the car on the simulation, then build it on Matlab/ Simulink. The result has indicated that the vehicle has optimized up to 1% when driving in two kinds of condition: Urban and Highway. The report is represented in 5 chapters, 68 pages (regardless of references and appendix). Firstly, at the beginning, we showed the reason for choosing this topic, topic’s objective, object researched and study range, research methods and literature review relate to the CVT system.
Secondly, in chapter 2, we found out the structural, control theory and model building simulation of CVT. In chapter 3, the model of vehicle equipped CVT system was built by the Matlab/ Simulink application consists: engine block, vehicle and PID controller. Next, the chapter 4 showed three kinds of cycle tests used to simulate the vehicle’s driving process, then analyze the data about performance and fuel consumption. In the final chapter, there exists the conclusion and recommendation for the next research.
ii Table of Contents Chapter 1 : INTRODUCTION .1 The reasons choosing this topic .3 Object and study range. 2 Chapter 2 : THEORETICAL BASIS .1 Main parts of CVT gearbox .2 Factors effect on CVT gearbox efficiency .2 Model building simulator .1 CVT Control Theory .2 Algorithm construction theoretical method and modeling. 19 Chapter 3 : USING MATLAB/SIMULINK TO MODEL VEHICLE .2 Modeling of CVT Vehicle .2 Continuous Variable Transmission model and Output parameters. 37 Chapter 4 : CYCLE TEST AND MODEL ANALYSIS .1 Steady State Speeds .2 Urban Dynamometer Driving Schedule.
65 iii Chapter 5 : CONCLUSION – RECOMMENDATION FOR FUTURE RESEARCH 68 5.2 Recommendation for future research. 69 iv LIST OF ACRONYMS CVT Continuous Variable Transmission PID Proportional – Integral - Differential RPM Revolutions Per Minute BSFC Brake Specific Fuel Consumption UDDS Urban Dynamometer Driving Schedule HWY Highway SSS Steady State Speeds v LIST OF FIGURES Figure 2.1 CVT and Vehicle Transmission Structure Sketch Map .2 The pulleys on CVT .3 Input and Output Shaft .4 Torque converter parts .5 Efficiency and Power loss of CVT gearbox .6 Overview of the Integrated Control on CVT engine .7 Valve characteristic lines .8 A kind of EM-CVT designed by Aichi Machine Industry .9 Forces acting on vehicle when going uphill .10 Forces acting on vehicle when going uphill .11 Power and torque performance for IC engine .12 Driveline system model .13 Input and output angular velocity and torque of driveline system .14 The angular velocity range (ω1, ω2) and engine’s working range .15 Mass flow rate map .17 BSFC Contour Map - Optimal fuel economy curve of engine.1 Overview of System Model .2 Engine System Model .3 Engine Torque Modeling .4 Mass Flow Rate Modeling.5 Fuel Consumption Modeling .8 Continuous Variable Transmission System Modeling .9 Angular velocity sensor .11 Forces calculation on active discs .12 Pressure calculation on Primary and Secondary Disc .13 Vehicle Body and Wheel model .14 Geometric Ratio Gearbox Design method for 4-speed gearbox .15 Ratio based on speed .16 Wheel torque with different ratio .17 Object ratio model A .18 Driveline transmission system .19 Object ratio model B .21 Transfer function and Speed Ratio Controller equipped PID .22 Optimal model testing .1 SSS Cycle test .2 UDDS Cycle test .3 HWy cycle test.4 Changing torque during acceleration in strategy A .5 Changing torque during acceleration in strategy B .6 Changing RPM during acceleration in strategy A .7 Changing RPM during acceleration in strategy B .8 Strategy A - object ratio and CVT ratio .9 Strategy B - object ratio and CVT ratio.10 Changing radius during acceleration in strategy A .11 Changing radius during acceleration in strategy B .12 Changing pressure during acceleration in strategy A .13 Changing pressure during acceleration in strategy B .14 CVT primary and secondary RPM in strategy B running in highway .15 CVT primary and secondary RPM in strategy B running in urban. 66 vii LIST OF TABLE Table 2.1 KpKs value table in accordance with gear ratio .2 Mass flow rate table .2 Engine Torque Linear Throttle Map .3 Engine Mass Flow Rate .4 CVT parameters selection .5 Honda Accord 2018 parameters .6 Working range for each mode .8 Maximum torque revolution .9 The optimal values .1 Fuel consumption table. 65 viii Chapter 1 : INTRODUCTION 1.1 The reasons choosing this topic In this day and age, due to the high income living, “Car” is the most keyword concerned by people.
Therefore, the automotive industry is more and more developed, as well as the technical applications belong to the car have been improved. One of the most significant techniques of automotive industry can be named as Continuous Variable Transmission (CVT). Though CVT was born on very old day but it still helpful in this era cause of its efficiency and convenience. Currently, car equipped with CVT gearbox is very familiar with us and its definition and fundamental have been researched in so many articles [1,2].
Because of its beneficial, the amount of automobile equipped with CVT is increasing significantly with the lack of energy resources annually and this brings us a huge problem about the fuel consumption. Otherwise, there exists lots of researchers on over the world join in finding out the solutions for saving fuel consumption and comfortable for drivers through CVT by optimizing different gear shifting rules [2]. On the other hand, some reports use the slip control method [3] to handle torque disturbances and is immune for speed ratio variations based on a detailed model. Moreover, optimizing test PID control for CVT by Matlab/Simulink [4] tends to be the trending method to research and survey CVT gearbox.
This method not only reduces the times of experiments on practical model but also determines the PID parameters quickly so it is very convenient for researchers to have a survey without doing too much experiments. Likewise, the aim of this thesis is to investigate the potential benefits of utilizing the PID algorithm in improving the efficiency of continuously variable transmission gearbox. Our group want to research thoroughly about CVT and apply the knowledge of subjects that taught at school to build the model of CVT Ratio control system [5] used Matlab/Simulink to define the target value of CVT real ratio trace. Based on the guide manual [6] from Transmission Lab Bosch, we will build the model to collect data, use PID to adjust parameters and make comparison between practical experiments and model simulation.
To sum up, the theoretical basis for applying the PID algorithm on enhancing CVT gearbox efficiency lies in its ability to adaptively adjust the transmission ratio based on real-time feedback, optimize the gearbox's performance and fuel efficiency and we want to achieve the deviation about 5% of both methods about to evaluate our project and apply it to practical if possible.2 Topic’s objective - Got knowledge about fundamental and structure of CVT gearbox - Build mathematical formulas to calculate the data 1 - Do experiments in Transmission Lab to gather the practical data - Achieve deviation about 5% between simulation and practical and make comparison between simulate data and practical data - Be able to enhance CVT efficiency by applying PID algorithm 1.3 Object and study range 1.1 Object “APPLY PID ALGORITHM ON CVT GEARBOX TO ENHANCE VEHICLE PERFORMANCE” implemented based on TestBench CVT in Transmission Lab. The objects that have been researched in this topic are technique parameters, operating procedure, algorithms and simulation blocks. PID controller designed for CVT gearbox in this report used to: - Apply on speed ratio controller - Build the transfer function equation for system - Select the most efficient parameters for PID Optimize the CVT gearbox efficiency: - Simulate the vehicle equipped with CVT system - Model and design the fuel consumption system - Estimate the system at the best performance and most economical point 1.2 Study range - Time: 18/09/2023 to 02/01/2024 - Place: HCMUTE - Field: Transmission - CVT 1.4 Research methods - Theoretical analysis methods: Research relative references (Scientific Articles) and CVT gearbox fundamental.5 Literature review Viet Nam: “NGHIÊN CỨU MÔ PHỎNG ĐỘNG LỰC HỌC CHUYỂN ĐỘNG THẲNG CỦA Ô TÔ SỬ DỤNG HỘP SỐ CVT DẠNG ĐAI TRUYỀN”. Nguyễn Trường Sinh, Lã Quốc Tiệp at Dynamic Faculty, Military Technical Academy.
Science and Technology Magazine. The authors presented the structure of Transmission system used CVT – Belt Forming and displayed the model simulate the dynamic that uses CVT drivetrain system to serve the research about Longitudinal Dynamic on Automotive. They calculated the Torque, Angular Velocity of pulley, transmission ratio from turbine shaft to pulley shaft as well as used some application like SimDriveline in Matlab/ Simulink to simulate the speed 2 ratio control signal of belt transmission, graphs of longitudinal dynamic velocity, acceleration, rotation speed, torque and transmission ratio of CVT. In conclusion, the authors from Military Technical Academy can estimate the Torque Transmission and Rotation Speed in HTTL in a car easily, then apply this method on other gearboxes.
“EXPERIMENTAL RESEARCH ON APPLYING CVT TEST BENCH TO EVALUATE THE EFFICIENCY OF CVT TRANSMISSION”. Nguyễn Lâm Trường Sơn, Vũ Trần Quang Duy and Hồ Dương Duy Anh under supervisor PhD. Dương Tuấn Tùng. Transmission Lab Bosch at HCMUTE.