Chapter three
Introduction to feedback
Section three: Block Diagrams
This chapter is on the theme of linear feedback control, for example with G(s) representing a system, M(s) a compensator and d an input disturbance signal:
This section focuses on the understanding and analysis of block diagrams. These diagrams are used to represent the feedback loops which are common place in many systems. Some of this material is covered more concisely in the analysis section.
1. What is a block diagram?
Introduces transfer functions and block diagram representations.
Transfer functions supporting video and notes (PDF, 493 KB).
Systems in series supporting video and notes (PDF, 473 KB).
Parallel systems supporting video and notes (PDF, 465 KB).
Has overlaps with early resources in feedback analysis section.
2. Feedback loops
Use of block diagrams to represent feedback loops and derivation of closed-loop transfer functions.
Summing junctions supporting video and notes (PDF, 594 KB).
Short cuts supporting video and notes (PDF, 457 KB).
Has overlaps with early resources in feedback analysis section.
3. More advanced loop structures
Practical loops often have multiple inputs (e.g. disturbances and noise) and more complex nested structures.
Multiple input systems supporting video and notes (PDF, 463 KB).