A feedback control system has the following characteristics: system type: 0 posi

Question

A feedback control system has the following characteristics:

system type: 0

position error constant: 34 dB

gain crossover frequency: 25 Hz

phase crossover frequency: 85 Hz

phase margin: 60 degrees

gain margin: 23 dB

It is desired to improve the steady-state accuracy by a factor of 5. How would you recommend doing this? Explain why you chose that answer.

(a) Increase the gain by 6 dB making error constant 40 dB.

(b) Use PI control to make the system type 2 and keep the gain margin greater than 23 dB.

(c) Use PD control to keep the system type 0 and the gain margin 23 dB.

(d) Use lead control to improve phase margin and decrease daming which will improve error.

(e) None of the above.

Explanation / Answer

The above specification can be achived by option (b)

We can use PI control to make the syatem type 2 and keep the gain margin greater than 23 dB due to following reasons

1. Since PI controller is used to remove the steady state error occurs from P controller and in terms of speed and stability the system has negative impact

2. by using integral controller the order of the closed loop system can be increased

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.