Continuous Control (SISO) - 9

Question 1

What are some possible extensions to the standard single-loop control?

Answer 1

Extensions of the standard control loop:
Feedforward control
Disturbance feedforwarding
Cascade control

Question 2

What is the benefit of feedforward control?

Answer 2

The denominator of the G(s) transfer functions is not changed, so the stability is unaffected. Furthermore, if it usually greatly improves reference tracking.

Question 3

What is the benefit of disturbance feedforwarding?

Answer 3

Similar to the feedforward case, stability is unchanged and can help to reduce the effect of disturbances, and in some cases, it can even reduce them to 0. However, usually it is required to have measurable disturbances.

Question 4

What is the concept of cascade control?

Answer 4

Cascade control typically solves control problems in cascades from fast
inner control loops to slower outer control loops. The concept is that the inner loop is faster enough such that we can approximate the GYR of the inner loop to 1 and design the controllers independently.

Question 5

What term is required to set steady error to 0 for plants of type 0?

Answer 5

The I is required so we need PID and not just P or PD.

Question 6

What are some methods of tuning PID controllers?

Answer 6

Root locus
Heuristic Tuning
Optimal tuning
Self-tuning