Control Systems
10ES43
10ES43 CONTROL SYSTEMS (Common to EC/TC/EE/IT/BM/ML)
Subject Code:10ES43 No. of Lecture Hrs./Week : 04 Total No. of Lecture Hrs.:52
IA Marks: 25 Exam Hours : 03 Exam Marks : 100
PART – PART – A A UNIT 1: Modeling of Systems: Introduction to Control Systems, Systems, Types of control systems, systems, Effect of feedback systems, Differential equations of physical systems – systems – Mechanical Mechanical systemsFriction, Translational systems (Mechanical accelerometer, Levered systems excluded), Rotational systems, Gear trains. Electrical systems, Analogous systems. 6 Hours UNIT 2: Block diagrams and signal flow graphs: Transfer functions, Block diagrams, Signal Flow graphs (Statevariable formulation excluded). 7 Hours UNIT 3: Time Response of feed back control control systems: Standard test signals, Unit step response of First and second order systems, Time response specifications, Time response specifications of second order systems, steady – steady – state state errors and error constants. 7Hours
UNIT 4: Stability analysis: Concepts of stability, Necessary conditions for Stability, Routh-Hurwitz stability criterion, Relative stability analysis; Special cases of RH criterion. 6 Hours PART – PART – B B UNIT 5: Root – – Locus Locus Techniques: Introduction, basic properties of root loci, Construction of root loci. 6 Hours UNIT 6: Stability analysis in frequency domain: Introduction, Mathematical preliminaries, Nyquist Stability criterion, (Inverse polar plots excluded ), Assessment of relative stability using Nyquist criterion, (Systems with transportation transportation lag excluded). 7Hours Department of EEE, SJBIT
Control Systems
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Control Systems
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UNIT 7: Frequency domain analysis: Correlation between time and frequency response, Bode plots, All pass and minimum phase systems, Experimental determination of transfer functions, Assessment of relative stability using Bode Plots. 7 Hours UNIT 8: Introduction to State variable analysis: Concepts of state, state variable and state models for electrical systems, Solution of state equations. 6 Hours TEXT BOOK : 1. Control Systems Engineering, I. J. Nagarath and M.Gopal, New Age International (P) Limited, 4 Edition – Edition – 2005 2005 2 Modern Control Engineering, Engineering, K. Ogata, PHI, 5th Edition, 2010.
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Control Systems
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Control Systems
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UNIT 7: Frequency domain analysis: Correlation between time and frequency response, Bode plots, All pass and minimum phase systems, Experimental determination of transfer functions, Assessment of relative stability using Bode Plots. 7 Hours UNIT 8: Introduction to State variable analysis: Concepts of state, state variable and state models for electrical systems, Solution of state equations. 6 Hours TEXT BOOK : 1. Control Systems Engineering, I. J. Nagarath and M.Gopal, New Age International (P) Limited, 4 Edition – Edition – 2005 2005 2 Modern Control Engineering, Engineering, K. Ogata, PHI, 5th Edition, 2010.
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Control Systems
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Control Systems
10ES43 Table of contents
Sl .no
Contents UNIT 1:Modeling of Systems:
Introduction to Control Systems
Types of control systems, Effect of feedback systems,
Differential equations of physical systems – systems – Mechanical Mechanical systems- Friction
1
Translational systems (Mechanical accelerometer, Levered systems excluded)
Rotational systems, Gear trains. Electrical systems, Analogous systems.
Page number
5 to 12
UNIT 2: Block diagrams and signal flow graphs
2
Transfer functions
Block diagram
Signal Flow graphs (Statevariable formulation excluded).
13 to 23
UNIT 3: Time Response of feed back control systems:
3
Standard test signals
Unit step response of First and second order systems,
Time response specifications
Time response specifications of second order systems, steady
state errors and error constants.
24 to 46
UNIT 4: Stability analysis:
Concepts of stability
Necessary conditions for Stability
4
47 to 65
Routh-Hurwitz stability criterion
Relative stability analysis
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Control Systems
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Special cases of RH criterion.
UNIT 5: Root – Locus Techniques:
5
Introduction
basic properties of root loci
Construction of root loci.
66 to 84
UNIT 6: Stability analysis in frequency domain:
6
Introduction
Mathematical preliminaries
Nyquist Stability criterion, (Inverse polar plots excluded)
Assessment of relative stability using Nyquist criterion,
85 to 102
UNIT 7: Frequency domain analysis:
7
Correlation between time and frequency response
Bode plots
All pass and minimum phase systems
Experimental determination of transfer functions
Assessment of relative stability using Bode Plots.
103 to 118
UNIT 8: Introduction to State variable analysis: Concepts of state 8
state variable and state models for electrical systems
Solution of state equations
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Control Systems
119 to 127
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UNIT-1 Modeling of Systems Introduction to control systems A system is an arrangement of or a combination of different physical components connected or related in such a manner so as to form an entire unit to attain a certain objective Control system is an arrangement of different physical elements connected in such a manner so as to regulate, director command itself to achieve a certain objective Requirements of good control system are accuracy, sensitivity, noise, stability, bandwidth, speed, oscillations
Types of control systems A system in which the control action is totally independent of the output of the system is called as open loop system
Example: Automatic hand driver, automatic washing machine, bread toaster, electric lift, traffic signals, coffee server, theatre lamp etc.
A system in which the control action is somehow dependent on the output is called as closed loop system The elements of closed loop system are command, reference input, error detector, control element controlled system and feedback element
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Control Systems
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Elements of closed loop system are: 1. Command : The command is the externally produced input and independent of the feedback control system. 2. Reference Input Element: It is used to produce the standard signals proportional to the command. 3. Error Detector : The error detector receives the measured signal and compare it with reference input. The difference of two signals produces error signal. 4. Control Element : This regulates the output according to the signal obtained from error detector. 5. Controlled System : This represents what we are controlling by feedback loop. 6. Feedback Element : This element feedback the output to the error detector for comparison with the reference input. Example: Automatic electric iron, servo voltage stabilizer, sun-seeker solar system, water level controller, human perspiration system.
Feedback system is that in which part of output is feeded back to input In feedback system corrective action starts only after the output has been affected Advantages of closed loop system: 1. Accuracy is very high as any error arising is corrected. 2. It senses changes -in output due to environmental or parametric change, internal disturbance etc. and corrects the same. 3. Reduce effect of non-linearities. 4. High bandwidth. 5. Facilitates automation. Disadvantages 1. Complicated in design and maintenance costlier. 2. System may become unstable.
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Control Systems
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