SMJE 3153 Control System. Department of ESE, MJIIT, UTM 2014/2015

Transcription

1 SMJE 3153 Control System Department of ESE, MJIIT, UTM 2014/2015 1

2 Course Outline Course Instructors Prof Nozomu Hamada Dr. Mohd Azizi Abdul Rahman Course Web site UTM e-learning site Schedule: Week1-5: Lecture(Hamada) Week6: TEST 1, Week7: Midterm break Week8-10: Lecture by Hamada Week11-14: Lecture by Dr. Azizi Week 15: Test 2, FINAL EXAM 2

3 UTM e-learning site Course web site Check the site often since it will be used to: convey any important announcement about the course distribute course material including Handout, Quiz, homework(hw), Assignments and their solutions etc. 3

4 Course Grading TEST 1 = 10 % TEST 2 = 10 % Two Assignments = 30% Final Examination = 50% 4

5 Textbook N. S. Nise, Control Systems Engineering, 6 th Edition, Wiely,2011 Lectures throughout this course are based on this text. It facilitates your self-study Way to purchase U & C book distributer, 105RM Order application List Close the list by 9 th September Books will be ready within 2 weeks (from Singapore) 5

6 Chapter 1 INTRODUCTION 6

7 7

8 1.1 INTRODUCTION Control System Definition 8

9 Control System Definition (Cont.) Control System consists of SUBSYSTEMs + PROCESS (or PLANTS) assembled for the purpose of obtaining A DESIRED OUTPUT with desired PERFORMANCE, given a SPECIFIED INPUT 9

10 Example: elevator (position control) 10

11 Example: elevator (Cont.) Specified input: push of the 4 th floor button Desired output: step function in Fig.1.2 location at 4 th floor level Performance: can be seen from the response curve in Fig. 1.2 measure 1. transient response measure 2. steady-state error slow response too fast response Passenger comfort vs. Patience 11

12 Example: elevator (Cont.) 12

13 Example: elevator (Cont.) Elevator as a control system Motor provides the power, and control systems regulate the position and speed 13

14 Example: Antenna Azimuth Control (case study throughout the text) position control system 14

15 Radio Telescope Antenna

16 potentiometer 16

17 Antenna Azimuth Control (Cont.) 17

18 Antenna Azimuth Control (Cont.) Schematic 18

19 Antenna Azimuth Control (Cont.) Block Diagram 19

20 Antenna Azimuth Control (Cont.) Commanded position 20

21 Advantages of Control Systems Four primary reasons in control system building 1. Power Amplification ex. antenna azimuth control 2. Remote Control ex. remoto-controlled robot 21

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23 Advantages of Control Systems (Cont.) Four primary reasons in control system building 3. Convenience of input form -by changing the form of the inputex. In temperature control system The position of thermostat is input which yields a desired thermal output (i.e. the output is heat) 4. Compensation for Disturbances ex. Antenna system must be able to detect the disturbance such as wind force and correct the antenna position. 23

24 temperature control system 24

25 1.2 HISTORY -Feedback control systems- Human Designed control systems 1. Liquid-level control 2. Steam pressure and temperature control 3. Speed control in steam engine 4. Stability and stabilization th century development 6. Contemporary applications 25

26 Ktesibios (300BC Greek) water clock 26

27 Edmond Lee (1745) Windmill control 27

28 Watt Governor(19 th century England) 28

29 Watt7s Governor(19 th century England) 29

30 Feedback amplifier (1930 USA) Black, Bode, Nyquist 30

31 Optical Disk Recording/Reading System 31

32 32

33 1.3 SYSTEM CONFIGURATION Open-loop system Convert the form of input to that used by the controller The output of an open-loop system is corrupted by two disturbances. The system cannot correct for these disturbances, either 33

34 Closed-loop (feed back) system *2 *1 The closed-loop system compensate for disturbances by measuring the output response feeding that measurement back (*1) comparing the output transduced response to the input 34 at the summing junction (*2)

35 Merits of Closed-loop (Feedback) system Able to compensate (correct) disturbance effect Greater accuracy Less-sensitive to noise Disadvantage More complex and more expensive Computer-controlled systems i.e. controller= digital computer time-sharing, software, supervisory function 35

36 1.4 Analysis and Design Objectives Analysis: process by which a system s performance is determined Design: process by which a system s performance is created or changed(*) * Change parameters or add additional components to meet the specifications 36

37 Three Objectives 1. Transient Response: improve the speed of system 2. Steady-State Response: accuracy of system, reduce the error 3. Stability : Control system must be stable, reliability 37

38 Stable system Unstable system 38

39 1.5 Design Process - six steps - 39

40 Design Process(Cont.) STEP 1. Transform requirements into a physical system: Requirements: the desire to position the antenna and describe antenna weight and physical dimension. design specifications such as desired transient response and steady-state accuracy STEP 2. Draw a functional block diagram: Describe the component parts of systems Fig. 1.9 (b) Detailed layout of the system 40

41 Antenna Azimuth Control (Cont.) Block Diagram 41

42 Design Process (Cont.) 42

43 Design Process (Cont.) STEP 3. Create a Schematic: Schematic diagram represents simplified or symbolic form Examples)

44 Antenna Azimuth Control (Cont.) Schematic 44

45 Design Process (Cont.) 45

46 Design Process (Cont.) STEP 4. Develop a Mathematical Model (Block diagram)

47 Design Process (Cont.) STEP 5. Reduce the Block Diagram: Ex.) described by transfer function 3. STEP Stablity 6. Analysis and Design of Control System Evaluated by standard test inputs 47

48 Three primary objectives: SUMMARY 48

49 SUMMARY 49

50 50

51 Course Outcome (CO) By the end of this course you should be able to CO1: Illustrate the basic principles of automatic control systems CO2: Model electrical, mechanical and electromechanical systems using transfer functions and find equivalent systems.

52 Course Outcome (CO) CO3: Analyze time response and stability of LTI transfer functions CO4: Tune controllers parameters using via Root Locus. CO5: Demonstrate the ability to solve control system problems by selecting appropriate tools in MATLAB.

53 Introduction Ch.1 Modeling in s-domain Ch.2 Modeling in s-domain Ch.3 Model Reduction Ch.5 Stability Ch.6 Time Response Ch. 4 Steady-State Error Ch.7 Root Locus Method Ch. 8 & Ch. 9 53