CONTROL SYSTEM SET 18

CONTROL SYSTEM SET 18

1. A system is called absolutely stable is any oscillations set up in the system are
a) Damped out
b) Self-sustaining and tend to last indefinitely
c) Negative peaked only
d) None of these
Ans: (a)
 
2. To increase damping of pair of complex roots compensator used is
a) Phase lag
b) Phase lead
c) Phase lag lead
d) One with 60° lead circuit
Ans: (b)
 
3. Best method to determine stability and transient response of the system is
a) Bode plot
b) Signal flow graph
c) Nyquist plot
d) Root locus
Ans: (c)
 
4. For type 3 system, lowest frequency asymptote will have the slop of
a) 15 db/octave
b) -16 db/octave
c) 17 db/octave
d) -18 db/octave
Ans: (d)
 
5. If poles of system are lying on the imaginary axis in s-plane, the system will be
a) Unstable
b) Marginally stable
c) Conditionally stable
d) Unstable
Ans: (b)
 
6. If a pole is added to a system it causes
a) Lag compensation
b) Lead compensation
c) Lead-lag compensation
d) None of these
Ans: (b)
 
7. The number of pure integrations in the system transfer function determine
a) Degree of stability
b) Stability of the system
c) Transient performance of the system
d) Steady state performance
Ans: (d)
 
8. For steady state transient improvement, compensator used is
a) Lead compensator
b) Lag compensator
c) Lead lag compensator
d) None of these
Ans: (c)
 
9. Which system conveniently see the impact of poles and zeros on phase and gain margin?

a) Root locus
b) Nyquist plot
c) Routh-Hurwitz criterion
d) Bode plot
Ans: (d)
 
10. Which gives the information between number of poles and zero of the closed loop transfer function?
a) Routh Hurwitz criterion
b) Bode diagram
c) Root locus method
d) Nyquist plot
Ans: (d)