MCQs on Control System Part-7

Control System

1. A first order dynamic linear system with a proportional controller exhibits an offset to a unit step input. The offset can be reduced by _____.

a. Decreasing the proportional gain

b. Adding integral mode

c. Adding derivative mode

d. Increasing the proportional gain

2. Addition of zeros in a transfer function causes______.

a. Lead-lag compensator

b. Lead compensator

c. Lag compensator

d. None of the above

3. A phase lead compensation network_______.

a. Is applied when error constants are specified

b. Reduces the steady state error

c. Decreases the system bandwidth

d. Speeds up the dynamic response

4. The input to a controller is______.

a. Error signal

b. Sensed signal

c. Desired variable signal

d. Servo signal

5. Addition of a pole to the closed-loop transfer function results in_____.

a. Increase in stability of the system

b. Increase in bandwidth

c. Reduction in maximum overshoot

d. Reduction in rise time

6. Which of the following properties is/are not exhibited by a phase lead network?

1. The velocity constant is usually increased

2. The slope of the magnitude curve is reduced at the gain cross over frequency

3. The bandwidth is reduced

4. The response becomes faster

a. 1,2,3 and 4 only

b. 2 and 3 only

c. 3 only

d. 1 only

7. The action of a PD controller is to______.

a. Reduce the rise time and maintain a constant value of steady state error of the system

b. Maintain a constant value of rise time and reduce the steady state error of the system

c. Reduce the rise time and increase the steady error of the system

d. Increase the rise time and steady state error of the system

8. The transfer function of a system is given as: 

a. Lag network

b. Lead network

c. Lag-lead network

d. Proportional network

9. Integral feedback control______.

a. Improves steady state response

b. Improves transient response

c. Reduces feedback time

d. None of the above

10. The industrial controller having the best steady state accuracy is______.

a. A proportional controller

b. A rate feedback controller

c. An integral controller

d. A derivative controller

11. With regard to the filtering property, the lead compensator and the lag compensators are respectively______.

a. Both low pass filters

b. Both high pass filters

c. High pass and low pass filters

d. Low pass and high pass filters

12. For arbitrary pole placement, the following combination is necessary______.

a. State feedback and controllability

b. Output feedback and controllability

c. Output feedback and observability

d. State feedback and stability

13. For a linear time invariant system, an optimal controller can be designed if_____.

a. The system is uncontrollable but stable

b. The system is stable and unobservable

c. The system is controllable and observable

d. The system is unstable but observable

14. The eigen values of linear system are the location of_______.

a. Poles of the system

b. Zeros of the system

c. Both (a) and (b)

d. Finite poles and zeros

15. Assertion (A) : Stepping motors are compatible with modern digital systems.

Reason (R) : The nature of command is in the forms of pulses.

a. A is false a but R is true

b. A is true but R is false

c. Both A and R are true and R is a correct explanation of A

d. Both A and R are true but R is not a correct explanation of A