Modern Control SystemEKT 308

• General Introduction• Introduction to Control System• Brief Review

- Differential Equation- Laplace Transform

Course Assessment

• Lecture 3 hours per week• Lab/Tutorial 2 hours per week

• Final Examination 50 marks• Class Test 1 10 marks• Class Test 2 10 marks• Lab Assessment 15 marks• Lab Test 10 marks• Attendance/Assignments 5 marks

Course Outcomes

• CO1: The ability to obtain the mathematical model forelectrical and mechanical systems and solve stateequations• CO2: The ability to perform time domain analysis with

response to test inputs and to determine the stabilityof the system.• CO3: The ability to perform frequency domain analysis

of linear system and to evaluate its stability using timeand frequency domain methods.• CO4: Ability to design lag, lead , lead-lag compensators

for linear control systems.

Tutorials/Lab HoursEvent Week Topic

Tutorial 1 2nd Differential EquationsTutorial 2 3rd Laplace TransformTutorial 3 4th Transfer FunctionsLab 1 5th Computational Approach for Modern

Control SystemsTutorial 4 6th Open-loop and Close-loop SystemsLab 2 7th Time-domain ResponseTutorial for Test 1 8th

Lab 3 9th Root LocusLab 4 11th Frequency Domain ResponseTutorial for Test 2 12th

Lab 5 13th Controller DesignLab Test 14th

Lecturers and PLV

• Lecturers1. Dr. Md. Mijanur Rahman2. En. Zahari Awang Ahmad

• PLV1. En. Mohammad Nazri Md. Noor

Text Book References

• Richard C. Dorf & Robert H. Bishop, “ModernControl Systems”, Twelfth Edition, PearsonEducation, Inc.• Katsuhiko Ogata, “Modern Control

Engineering”, Fifth Edition, Pearson Education,Inc.

What is a Control System ?

• A device or a set of devices• Manages, commands, directs or

regulates the behavior of otherdevices or systems.

What is a Control System ? (contd….)

Process (Plant) to be controlled

Process with a controller

Examples

Examples (contd…)

HumanControl

System Control

Classification of Control Systems

Control systems are often classified as• Open-loop Control System

• Closed-Loop Control SystemsAlso called Feedback orAutomatic Control System

Open-Loop Control System

Day-to-day Examples• Microwave oven set to operate for fixed time• Washing machine set to operate on fixed

timed sequence.

No Feedback

Open-Loop Speed Control of Rotating Disk

For example, ceiling or table fan control

What is Feedback?Feedback is a process whereby someproportion of the output signal of asystem is passed (fed back) to the input.This is often used to control the dynamicbehavior of the System

Closed-Loop Control System

• Utilizes feedback signal (measure of theoutput)• Forms closed loop

Example of Closed-Loop ControlSystem

Controller:Driver

Actuator:SteeringMechanism

The driver uses the differencebetween the actual and the desireddirection to generate a controlledadjustment of the steering wheel

Closed-Loop Speed Control of Rotating Disk

GPS Control

Satellite Control

Satellite Control (Contd…)

Servo Control

Disk Drive Control

Closed-Loop Control of Disk Drive

Differential Equation

0..... 011

1

1

adxdya

dxyda

dxyda n

n

nn

n

n

N-th order ordinary differential equation

Often required to describe physical system Higher order equations are difficult tosolve directly. However, quite easy to solve throughLaplace transform.

Example of Diff. Equation

o

i

edtiC

edtiC

RidtdiL

1

1

Example of Diff. Equation (Contd…)

Newton’s second law:

2

2

dtsdm

dtds

dtdmF

dtdvmF

maF

Table 2.2 (continued) Summary of Governing Differential Equations for Ideal Elements