Post on 28-Oct-2014
CƠ SỞ TỰ ĐỘNG
Giảng viên: Nguyễn Đức HoàngBộ môn Điều Khiển Tự Động
Khoa Điện – Điện TửĐại Học Bách Khoa Tp.HCM
Email: ndhoang@hcmut.edu.vn
MÔN HỌC
Nội dung môn học (10 Nội dung môn học (10 chương)chương)
(14 tuần = 42 tiết LT + 14 tiết BT)(14 tuần = 42 tiết LT + 14 tiết BT)Chương 1: Giới thiệu về hệ thống điều khiển tự động
Chương 2: Mô hình toán học hệ thống liên tục
Chương 3: Đặc tính động học
Chương 4: Khảo sát tính ổn định của hệ thống
Chương 5: Chất lượng hệ thống điều khiển
Chương 6: Thiết kế hệ thống tuyến tính liên tục
Chương 7: Mô hình toán học hệ rời rạc
Chương 8: Phân tích hệ rời rạc
Chương 9: Thiết kế hệ rời rạc
Chương 10: Ứng dụng
Tài liệu tham khảoTài liệu tham khảo
Giáo trình: Giáo trình: Lý thuyết điều khiển Lý thuyết điều khiển
tự độngtự độngNguyễn Thị Phương Hà – Huỳnh Thái HoàngNguyễn Thị Phương Hà – Huỳnh Thái Hoàng
NXB Đại Học Quốc Gia TpHCMNXB Đại Học Quốc Gia TpHCM
Bài tập: Bài tập: Bài tập điểu khiển tự Bài tập điểu khiển tự
độngđộngNguyễn Thị Phương HàNguyễn Thị Phương Hà
Tài liệu: Tài liệu:
Automatic Control SystemAutomatic Control System
Modern Control System Theory Modern Control System Theory
and Designand Design
Đánh giáĐánh giá
Thi giữa kỳ : 20%Thi cuối kỳ : 80%Có cộng điểm BT vào điểm thi cuối kỳ (≤1.0đ)
GIỚI THIỆU VỀ HỆ THỐNG GIỚI THIỆU VỀ HỆ THỐNG ĐIỀU KHIỂN TỰ ĐỘNGĐIỀU KHIỂN TỰ ĐỘNG
CHƯƠNG 1
Control Systems 6
1769
• James Watt’s steam engine and governor developed.The Watt steam engine is often used to mark the beginning of the Industrial Revolution in Great Britain. During the Industrial Revolution, great strides were made in the development of mechanization, a technology preceding automation.
Control
• Control is a sequence of decisions aimed at the attainment of specified objectives in an environment of uncertainty and presence of disturbances.
Control system
• A control system is an arrangement of physical components connected or related in such a manner as to command, direct, or regulate itself or another system.
Input
• The input is the stimulus, excitation or command applied to a control system.
• Typically from external energy source, usually in order to produce a specified response from the control system.
Output
• The output is the actual response obtained from a control system.
• It may or may not be equal to specified response implied by the input.
History of Automatic Control
Prior to World War II
A main impetus for the use of feedback in the United States was the development of the telephone system and electronic feedback amplifiers by Bode, Nyquist, and Black at Bell Telephone Laboratories.
Prior to World War II
The Russian theory tended to utilize a time-domain formulation using differential equations.
World War II
Design and construct:• automatic airplane pilots, • gun-positioning systems, • radar antenna control systems.
Sputnik and space age
The time-domain methods developed by Liapunov, Minorsky, and others have met with great interest in the last two decades.
Recent time
Recent theories of optimal control developed by L.S. Pontryagin in the former Soviet Union and R. Bellman in the United States, and studies of robust systems, have contributed to the interest in time-domain methods.
Terms and Concepts
Two Types of Control Systems
• Open Loop– No feedback– Difficult to control
output with accuracy
• Closed Loop– Must have feedback– Must have sensor on output– Almost always negative
feedback
Open-loop and closed-loop systems
Open-loop control
An open-loop control system utilizes an actuating device to control the process directly without using feedback.
A common example of an open-loop control system is an electric toaster in the kitchen.
Closed-loop control
A closed-loop control system uses a measurement of the output and feedback of this signal to compare it with the desired output.
A person steering an automobile by looking at
the auto’s location on the road and making the appropriate adjustments.
Control Systems
Manual control system
Goal: Regulate the level of fluid by adjusting the output valve.
The input is a reference level of fluid and is memorized by operator.The power amplifier is the operator.The sensor is visual.Operator compares the actual level with the desired level and opens or closes the valve ( actuator).
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The level of fluid in a tank control.
30
Multivariable control system
A robot is a computer-controlledmachine.
Industrial robotics is a particular field of automation in which the robot is designed to substitute for human labor.
The Honda P3 humanoid robot.
The Control System Design Process
• Design is the process of conceiving or inventing the forms, parts, and details of a system to achieve a specified purpose.
Engineering design
Engineering design
Trade-off The result of making a judgment about how to
compromise between conflicting criteria.
Given a process, how to design a feedback control system?
Three steps:
• Modeling. Obtain mathematical description of the systems.
• Analysis. Analyze the properties of the system.
• Design. Given a plant, design a controller based on performance specifications.
Design examples
Rotating disk speed control
Control Systems
Step 1. Control goal
• Design a system that will held a rotating disk at a constant speed. Ensure that the actual speed of rotation is within a specified percentage of desired speed.
Control Systems
Step 2. Variable to be controlled
• Speed of rotation disc
Control Systems
Step 3. Control design specification
• Design a system that will ensure that the actual speed of rotation is within a specified percentage of desired speed.
Control Systems
Step 4 Preliminary system configuration
Control Systems
Step 4 Preliminary system configuration
Control Systems
Insulin delivery system
The blood glucose and insulin concentrations for a healthy person.
Control Systems
Step 1. Control goal
• Design a system to regulate the blood sugar concentration of a diabetic by controlled dispensing of insulin.
Control Systems
Step 2. Variable to be controlled
• Blood glucose concentration
Control Systems
Step 3. Control design specification
• Provide a blood glucose level for the diabetic that closely approximates the glucose level of a healthy person.
Control Systems
Step 4 Preliminary system configurations
Control Systems
Disk drive read system
Control Systems
Control Systems
Step 1. Control goal
• Design a system that will held the position the reader head to read the data stored on a track on the disk.
Control Systems
Step 2. Variable to be controlled
• Position of the reader head
Control Systems
Step 3. Control design specification
• Design a system that will ensure that the head : - “flies” above the disk at a distance of less than 100 nm, - with the position accuracy is 1 m,- with speed from track to track 50 ms
Control Systems
Step 4 Preliminary system configuration
Control Systems
P1.8 Student-teacher learning process
• Construct a feedback model of the learning process and identify each block of the system.
Control Systems
P1.8 Student-teacher learning process
Inverted pendulum control
• E1.11 Sketch the block diagram of a feedback control system. Identify the process, sensor, actuator, and controller.The objective is keep the pendulum in the upright position ( = 0), in the presence of disturbances.
Control Systems
Control Systems
Inverted pendulum control