


CIRCUIT THEORY AND CONTROL
Group A
Graph of a network. Concept of tree, concepts of loop current and node pair voltage, circuits
cutset and cutset matrices, formulation of equilibrium equations of the loop and node basis.
Mesh and nodal analysis.
Laplace transform. Transient response using Laplace transform. Initial and final value
theorems. Unit step, impulse, ramp functions. Laplace transform for shifted and' singular
functions.
The convolution integral, Fourier series, complex exponential form of the Fourier series. The
frequency spectra of periodic waveforms and their relationship to Laplace transform.
The concept of complex frequency, transform impedance and admittance; series .and parallel
combinations. Frequency response, coupled circuits.
Terminals and terminal pairs, driving point impedance, transfer functions, poles and zeros,
restrictions on pole and zero locations in splane. Analysis of 1port and 2port networks.
Time domain behavior from pole and zero plot, sinusoidal network functions in terms of
poles and zeros. Resonance, Q and bandwidth of a circuit.
Introduction to synthesis of passive networks: Butterworths, Chebyshev and Bessel type low
pass, high pass, band pass and band rejection filters.


Group B
Introduction: Basic concepts and symbols, open loop and closed loop systems, effects of
feedback. Concepts of linear and nonlinear systems. Definition of transfer function. Block
diagram representation. Signal flow graphs.
Servo components: Mathematical modelling and simulation of dynamic systems. Synchros,
potentiometers, gyros. d.c. and a.c. servomotors. d.c.. and a.c. tachogenerators. Power and
preamplifiers. Modulators and demodulators. Position and speed control systems.
Time response: Typical test input' signals. Time domain performance of first and second
order systems to impulse, step, ramp and sinusoidal inputs. Definition of error coefficients
and steady state error.
Stability: RouthHurwitz criteria.
Frequency response: Frequency domain specifications. Bode plots. Polar plots.
Regulators and controllers. Proportional, PI and PID controllers.
