AUTOMATIC CONTROL SYSTEMS QUIZ

For a stable system having two or more gain crossover frequencies the phase margin is measured at the highest crossover frequency.

True

False

TRUE ANSWER : ?
YOUR ANSWER : ?

Gain margin and phase margin can be determined from Bode plots as well as Nyquist plot.

False

True

TRUE ANSWER : ?
YOUR ANSWER : ?

If the poles lie in second quadrant, damping ratio is

more than 1

zero

less than 1

1

TRUE ANSWER : ?
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The addition of a pole to the open loop transfer function pulls the root locus

Towards right or left depending on the position of new pole

None of these

To the right

To the left and making the system more stable

TRUE ANSWER : ?
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A system is highly oscillatory if

Gain margin is high

Gain margin is close to 1 or phase margin is zero

Gain margin is close to 1

Gain margin is high and phase margin is 180°

TRUE ANSWER : ?
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Which of the following features is not associated with Nichols chart?

It is symmetric about -180°

M loci are centred about (0 dB, -180°) point

The frequency at intersection of G(j?) locus and M = +3 dB locus gives bandwidth of closed loop system

(0 dB, -180°) point on Nichols chart represent critical Point (-1, 0)

TRUE ANSWER : ?
YOUR ANSWER : ?

DC tachogenerator can be used in

Speed control system

Position control system

Both A and B

Neither A nor B

TRUE ANSWER : ?
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Nichol’s chart is symmetric about – 180° axis.

False

True

TRUE ANSWER : ?
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In force current analogy, displacement x is analogous to

Charge

Electrostatic energy

Magnetic flux linkage

Voltage

TRUE ANSWER : ?
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Integral control action

Neither (a) nor (b)

May lead to oscillatory response

Both (a) and (b)

Removes offset

TRUE ANSWER : ?
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