CONTROL THEORY
EMMANUEL EFFAH
GTUC
Outline
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COURSE DETAILS
COURSE OUTLINE
INTRODUCTION
CONCEPT OF CONTROL
COURSE DETAILS
OBJECTIVES
• By the end of this course successful students will
be able to;
• Appreciate the relevance of control systems
engineering in their field of study.
• Mathematically model simple dynamic systems.
• Use tools and techniques to analyse various
dynamic systems.
• Design proportional controllers for feedback
control systems.
• RECOMMENDED TEXT
• Modern Control Engineering, 4th edition, 2002 (ISBN:
0130609072), K. Ogata, Prentice Hall.
• Control Systems Engineering, 4th edition, 2004 (ISBN:
0471445770), Norman S. Nise, Wiley.
• Automatic Control Systems, 8th edition, 2003 (ISBN:
0471134767), B. C. Kuo, John Wiley & Sons.
• Feedback systems: An introduction to scientists and
engineers, Karl J Astrom and Richard Murray.
• Modern Control Systems, 10th edition, 2005 (ISBN:
0-13-127765-0), R.C. Dorf & R.H. Bishop, Prentice Hall.
COURSE OUTLINE
• CONCEPT OF CONTROL
• SYSTEM MODELLING
• TRANSIENT RESPONSE ANALYSIS AND STEADY-STATE
ERROR ANALYSIS
• ROOT LOCUS METHOD
• FREQUENCY RESPONSE ANALYSIS
• COMPENSATION TECHNIQUES
❖ Introduction to MATLAB in control systems
Week
Topic
1
Introduction to
control theory
and MATLAB
2 and 3
System Modelling
4-7
Transient
response analysis
and steady state
error analysis
8
Root locus
method
Frequency
response analysis
Properties of root locus, analysis of systems using root locus
using MATLAB
Concept of frequency response analysis, sketching bode plots,
phase and gain margin of transfer functions, sketching Nyquist
plot, phase and gain margin of transfer functions on Nyquist
plot, analysis of frequency responses and design using MATLAB
Compensation
techniques
Introduction to lead/lag compensators, Introduction to PID
controllers, design of PID controllers for systems
9 -11
12 and 13
Content
Concept of control, introduction to MATLAB and SIMULINK
for control engineering, delivering mini project to students.
Overview of Laplace transforms, differential equations,
modelling of various dynamic systems i.e. electrical
systems, mechanical systems, inverse Laplace
transforms
Transfer functions, first order responses, second order
responses, steady state error for unity feedback systems,
designing gain of a closed loop system to meet steady
state error specifications
Evaluation
Continuous Assessment
ASSESSMENT TOOL
EXPECTED DUE DATE
WEIGHT/30
Assignments,
Attendance
Assignment: one week
after problems are
assigned
Attendance: randomly
taken at lectures
5
Quizzes
unannounced
3
Midsemester
examinations
*7 th week
8
Mini project
After final exams (18 th
December 2019)
14
Final Exam: final examination is allotted 70% of the total score expected
in this course. Students should note that the final exam is largely
dependent on activities during the continuous assessment; examination
are based on the knowledge and application of concepts introduced
during the semester
INTRODUCTION
CONTROLLER
VARIABLES
SYSTEM
CONTROL
SYSTEM
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System
Combination of components that work together to perform a certain task
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Controller
A system that effects control on another based on a specified control objective
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Control system
The overall system comprising the plant and the controller and the required
interconnections of inputs and outputs that determine how these subsystems
influence each other
INTRODUCTION
• Control systems are everywhere ;
- In the physical world ( man-made and nature
- In the nonphysical world
Illustration: The Impact of Control Technology, T. Samad and A.M. Annaswamy (eds.), 2011
Control design process
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Establish the goal
Identify the variables to be controlled
Write the specifications
Establish the system configuration
Obtain a model of the process, the actuator and
the sensor
• Describe a controller and select key parameters
to be adjusted
• Optimize the parameters and analyse the
performance
Concept – system configuration
CONCEPT - EXAMPLE
Manipulated variable
Which variable can be manipulated?
Answer: the setting of valve V1
Concept - example
Controlled variable
What are we trying to control?
Level of liquid in the tank, measured by Level indicator L1
Disturbance variable
What has an impact on the system but we cant manipulate?
Flow-rate of liquid from its source measured by flowmeter F1