SMJE 3153 Control System

Department of ESE, MJIIT, UTM

2014/2015

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Course Outline

►Course Instructors Prof Nozomu Hamada (hamada@utm.my)and 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

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Course web site

UTM e-learning 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.

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Course Grading

►TEST 1 = 10 % ►TEST 2 = 10 % ►Two Assignments = 30% ► Final Examination = 50%

Textbook

N. S. Nise, Control Systems Engineering,

6th 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 9th September Books will be ready within 2 weeks (from Singapore) 5

Chapter 1

INTRODUCTION

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1.1 INTRODUCTION

Control System Definition

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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

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Example: elevator (position control)

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Example: elevator (Cont.)

Specified input: push of the 4th floor button Desired output: step function in Fig.1.2 location at 4th 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

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Example: elevator (Cont.)

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Example: elevator (Cont.)

Elevator as a control system Motor provides the power, and control systems regulate the position and speed

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Example: Antenna Azimuth Control (case study throughout the text)

14 position control system

Radio Telescope Antenna

16 potentiometer

Antenna Azimuth Control (Cont.)

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Antenna Azimuth Control (Cont.)

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Schematic

Antenna Azimuth Control (Cont.)

19 Block Diagram

Antenna Azimuth Control (Cont.)

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Commanded position

Advantages of Control Systems Four primary reasons in control system building

1. Power Amplification ex. antenna azimuth control

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2. Remote Control ex. remoto-controlled robot

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Advantages of Control Systems (Cont.) Four primary reasons in control system building

3. Convenience of input form -by changing the form of the input- ex. In temperature control system The position of thermostat is input which yields a desired thermal output (i.e. the output is heat)

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4. Compensation for Disturbances ex. Antenna system must be able to detect the disturbance such as wind force and correct the antenna position.

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temperature control system

1.2 HISTORY -Feedback control systems-

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Human Designed control systems 1. Liquid-level control 2. Steam pressure and temperature control 3. Speed control in steam engine 4. Stability and stabilization 5. 20th century development 6. Contemporary applications

Ktesibios (300BC Greek) water clock

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Edmond Lee (1745) Windmill control

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Watt Governor(19th century England)

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http://www.youtube.com/watch?v=kfQPJ3WRfWo

Watt7s Governor(19th century England)

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Feedback amplifier (1930 USA) Black, Bode, Nyquist

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Optical Disk Recording/Reading System

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1.3 SYSTEM CONFIGURATION

Open-loop system

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The output of an open-loop system is corrupted by two disturbances. The system cannot correct for these disturbances, either

Convert the form of input to that used by the controller

Closed-loop (feed back) system

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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 at the summing junction (*2)

*1

*2

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

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1.4 Analysis and Design Objectives

Analysis: process by which a system’s performance is determined

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Design: process by which a system’s performance is created or changed(*) * Change parameters or add additional components to meet the specifications

Three Objectives

1. Transient Response: improve the speed of system

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2. Steady-State Response: accuracy of system, reduce the error

3. Stability : Control system must be stable, reliability

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Stable system

Unstable system

1.5 Design Process - six steps -

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Design Process(Cont.)

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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

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STEP 2. Draw a functional block diagram: Describe the component parts of systems

Fig. 1.9 (b) Detailed layout of the system

Antenna Azimuth Control (Cont.)

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Design Process (Cont.)

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Design Process (Cont.)

STEP 3. Create a Schematic: Schematic diagram represents simplified or symbolic form

Examples)

Antenna Azimuth Control (Cont.)

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Schematic

Design Process (Cont.)

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Design Process (Cont.)

STEP 4. Develop a Mathematical Model (Block diagram)

Design Process (Cont.)

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3. Stablity

STEP 5. Reduce the Block Diagram: Ex.) described by transfer function

STEP 6. Analysis and Design of Control System Evaluated by standard test inputs

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SUMMARY Three primary objectives:

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SUMMARY

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Course Outcome (CO)

►CO1: Illustrate the basic principles of automatic control systems

►CO2: Model electrical, mechanical and electromechanical systems using transfer functions and find equivalent systems.

By the end of this course you should be able to

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.

Modeling in s-domain Ch.2

Time Response Ch. 4

Stability Ch.6 Steady-State

Error Ch.7

Root Locus Method

Ch. 8 & Ch. 9

Model Reduction

Ch.5

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Introduction Ch.1

Modeling in s-domain

Ch.3