Syllabus - Control Systems (BM601)

Modeling of Dynamic Systems and Simulation

Integro-differential equation of linear systems such as mechanical, hydraulic, pneumatic and electrical systems. Block diagram and Signal flows graph method of representing the dynamic equations, analogue simulation, linearity, impulse response and concept of transfer function, Mason’s gain formula, control system components: errors detectors ac and dc servomotors, servo amplifier( ac & dc) using operational amplifiers, gyro, resolver. Typical study of characteristics of these components. Concept of feedback as control theory- Mathematical theory of feedback, return ratio, return difference, open and closed loop, understanding the necessity of feedback as real control action supplemented by a small example.

Time-Domain Analysis of Feedback Control Systems

Typical references test signals and their significance, transient behavior of closed loop systems under feedback control. Proportional plus derivative and rate feedback control actions for improving the transient response. Steady state behavior of closed loop feedback control systems. Types of open loop transfer functions. Steady state errors. Proportional plus integral control action for the improvement of steady state errors.

Frequency-Domain Analysis of Feedback Control Systems

Concept of frequency-domain analysis, Bode plots, polar plots. Bode of closed loop transfer function and bode plots of error transfer functions, principle of argument, Nyquist criteria. Conditionally stable closed loop systems, transportation lag, constant M and constant N loci, Loci of closed loop poles (root loci).

Compensation Techniques

Need for frequency-domain compensation, different types of compensation, phase lead and phase lag compensation, design of compensating networks for the desired frequency-domain close loop performance.

State Space Method of Analysis

Fundamentals of state space: Concept of state variables. Representation of linear system through state dynamics, calculation of Eigen values and Eigen vectors, modal matrix, modal transformation, elementary understanding of controllability and observability, state feedback control. Stability analysis of feedback. Control system-concept of stability: BIBO stability, asymptotic stability, Routh-Hurwitz analysis. Nyquist stability analysis and relative stability, gain margin and phase margin.