Control Systems - Study Mode

Show All Answers

[#181] Which one of the following compensation is adopted for improving transient response of a negative unity feedback system?

(A) Phase lead compensation

(B) Phase lag compensation

(C) Gain compensation

(D) Both phase lag compensation and gain compensation

Correct Answer

(A) Phase lead compensation

[#182] A liquid level controller linearly converts a displacement of 2 m to 3 m into 4-20 mA control signal. A relay serves as two position controller to open and close an inlet valve. Relay closes at 12 mA and opens at 10 mA. The hysteresis zone is:

(A) 0.1 m

(B) 0.125 m

(C) 0.15 m

(D) 0.2 m

Correct Answer

(B) 0.125 m

[#183] Given the system transfer function $$Gleft( s
ight) = frac{{K{e^{ - 0.2s}}}}{{sleft( {s + 2}
ight)left( {s + 8}
ight)}},$$ xa0 xa0 the corner frequencies in rad/s are

(A) 0.2, 0.6

(B) 1, 4

(C) 3, 7

(D) 2, 8

Correct Answer

(D) 2, 8

[#184] A second order LTI system is described by the following state equations [frac{{
m{d}}}{{{
m{dt}}}}] x 1 (t) - x 2 (t) = 0 [frac{{
m{d}}}{{{
m{dt}}}}] x 2 (t) + 2x 1 (t) + 3x 2 (t) = r(t)
where x 1 (t) and x 2 (t) are the two state variables and r(t) denotes the input. The output c(t) = x 1 (t). The system is

(A) undamped (oscillatory)

(B) underdamped

(C) critically damped

(D) overdamped

Correct Answer

(D) overdamped

[#185] Where are the K = ±∞ points on the root loci of the characteristic equation of the closed loop control system located at?

(A) Poles of G(s)H(s)

(B) Zeroes of G(s)H(s)

(C) Both Zeros and Poles of G(s)H(s)

(D) Neither at Zeros nor at Poles of G(s)H(s)

Correct Answer

(B) Zeroes of G(s)H(s)