CONTROL SYSTEM-I
EE-503
Credit: 4
Introduction to control system: Concept of feedback and Automatic control, Effects of feedback,
Objectives of control system, Definition of linear and nonlinear systems, Elementary concepts of
sensitivity and robustness. Types of control systems, Servomechanisms and regulators, examples of
feedback control systems. Transfer function concept. Pole and Zeroes of a transfer function. Properties
of Transfer function.
Mathematical modeling of dynamic systems: Translational systems, Rotational systems, Mechanical
coupling, Liquid level systems, Electrical analogy of Spring–Mass-Dashpot system. Block diagram
representation of control systems. Block diagram algebra. Signal flow graph. Mason’s gain formula.
Control system components: Potentiometer, Synchros, Resolvers, Position encoders. DC and AC
tacho-generators. Actuators. Block diagram level description of feedback control systems for position
control, speed control of DC motors, temperature control, liquid level control, voltage control of an
Alternator.
Time domain analysis: Time domain analysis of a standard second order closed loop system. Concept
of undamped natural frequency, damping, overshoot, rise time and settling time. Dependence of time
domain performance parameters on natural frequency and damping ratio. Step and Impulse response of
first and second order systems. Effects of Pole and Zeros on transient response. Stability by pole
location. Routh-Hurwitz criteria and applications.
Error Analysis: Steady state errors in control systems due to step, ramp and parabolic inputs.
Concepts of system types and error constants.
Stability Analysis: Root locus techniques, construction of Root Loci for simple systems. Effects of
gain on the movement of Pole and Zeros.
Frequency domain analysis of linear system: Bode plots, Polar plots, Nichols chart, Concept of
resonance frequency of peak magnification. Nyquist criteria, measure of relative stability, phase and
gain margin. Determination of margins in Bode plot. Nichols chart. M-circle and M-Contours in
Nichols chart.
Control System performance measure: Improvement of system performance through compensation.
Lead, Lag and Lead- lag compensation, PI, PD and PID control.
Numerical problems to be solved in the tutorial classes.
Text books:
1.
Modern Control Engineering, K. Ogata, 4th Edition, Pearson Education.
2.
Control System Engineering, I. J. Nagrath & M. Gopal. New Age
International Publication.
3.
Control System Engineering, D. Roy Choudhury, PHI
4.
Automatic Control Systems, B.C. Kuo & F. Golnaraghi, 8th Edition, PHI
Reference Books:
1. Control Engineering Theory & Practice, Bandyopadhyaya, PHI
2. Control systems, K.R. Varmah, Mc Graw hill
3. Control System Engineering, Norman Nise, 5th Edition, John Wiley & Sons
4. Modern Control System, R.C. Dorf & R.H. Bishop, 11th Edition, Pearson
Education.
5. Control System Design, C. Goodwin Graham, F. Graebe F. Stefan, Salgado.
E. Mario, PHI
6. Modeling & Control of dynamic system, Macia & Thaler, Thompson
7. Modern Control Technology Components & Systems, 3rd edition, C.T Kilian,
Cengage Learning.
8. Modern Control Engineering, Y. Singh & S. Janardhanan, Cengage Learning
9. Control System Engineering, R. Anandanatarajan & R. Ramesh Babu, ,
SCITECH
10. Automatic Control system, A. William, Wolovich, Oxford