Course Contents

• Introduction to Control Systems
  Definition, examples of control systems. Open-loop and closed-loop control systems. Review of Laplace and inverse Laplace transforms.

• System Modelling
  

Signal flow graph, block diagram. Transfer function. Poles and zeros. Block diagram reduction using signal flow graph and block diagram reduction techniques. Mechanical, electrical and electromechanical systems. First and second order models, higher order models.

• Transient Response Analysis and Steady-state Error Analysis
  

Definitions of transient response parameters. Analysis of second-order system as prototype. Routh-Hurwitz stability criterion. Classification of systems based on steady-state characteristics, steady-state error coefficient.

• Root Locus Method
  

Definition of root locus, Properties of root locus, sketching of root locus plots. Effect of open-loop zeros and poles. Root locus design concepts.

• Frequency Response Analysis
  

Bode diagram, Polar plot, Nichols plot. Nyquist stability criterion: non-mathematical description of Nyquist criterion, interpretation of stability. Relative stability - Gain and phase margins. Closed-loop frequency response analysis - M and N contours, Nichols chart.

• Compensation Techniques
  

Compensation techniques: lag, lead and lag-lead compensation, PD, PI and PID controllers. Cascade compensation based on root-locus method. Introduction to Feedback compensation.

Learning Outcome of Subject

At the completion of the subject, students should be able to perform the following tasks:

• differentiate between open-loop and closed-loop control.
• apply signal flow graph and block diagram reduction techniques.
• model mechanical, electrical and electromechanical systems using differential equations.
• perform transient and steady-state analysis.
• explain the concept of stability.
• apply the root locus method of analysis.
• derive the frequency response of a system and calculate the gain, phase, gain margin and phase margin.
• analyse Bode plots and polar plots.
• design lead-lag and PID compensation for control systems

Programme Outcomes (% of contribution)

• Ability to acquire and apply fundamental principles of science and engineering - 10%
• Capability to communicate effectively - 10%
• Acquisition of technical competence in specialised areas of engineering discipline - 40%
• Ability to identify, formulate and model problems and find engineering solutions based on a systems approach - 15%
• Ability to conduct investigation and research on engineering problems in a chosen field of study- 10%
• Understanding of the importance of sustainability and cost-effectiveness in design and development of engineering solutions - 5%
• Ability to work effectively as an individual, and as a member/leader in a team - 10%