Control Systems (ECE Perspective) – Multiple Choice Questions (MCQs)

1. 49. The transfer function of a proportional controller is:

   • A. Kp
   • B. Kp/s
   • C. Kp*s
   • D. Kp/(1+sT)

2. 50. The transfer function of an integral controller is:

   • A. Ki
   • B. Ki/s
   • C. Ki*s
   • D. Ki/(1+sT)

3. 51. The transfer function of a derivative controller is:

   • A. Kd
   • B. Kd/s
   • C. Kd*s
   • D. Kd/(1+sT)

4. 52. The characteristic equation of a unity feedback system with open-loop transfer function G(s) is:

   • A. 1 + G(s) = 0
   • B. 1 - G(s) = 0
   • C. G(s) = 0
   • D. 1/G(s) = 0

5. 53. The time response of a control system is usually analyzed for standard test inputs such as:

   • A. Step input
   • B. Ramp input
   • C. Impulse input
   • D. All of the above

6. 54. The "steady-state" response of a system refers to its behavior as time approaches:

   • A. Zero
   • B. Infinity
   • C. One
   • D. The time constant

7. 55. The concept of "limit cycle" is typically associated with:

   • A. Linear systems
   • B. Non-linear systems
   • C. Stable systems
   • D. First-order systems

8. 56. The transfer function of a second-order system is characterized by:

   • A. One pole and one zero
   • B. Two poles
   • C. One pole
   • D. Two poles and two zeros

9. 57. If the gain margin is negative

   • A. the system is:
   • B. Stable
   • C. Unstable
   • D. Marginally stable

10. 58. If the phase margin is negative

    • A. the system is:
    • B. Stable
    • C. Unstable
    • D. Marginally stable

11. 59. The concept of "dominant poles" is relevant when approximating a higher-order system by a lower-order system to analyze its:

    • A. Steady-state behavior
    • B. Transient behavior
    • C. Frequency response
    • D. Stability

12. 60. The final value theorem for Laplace transform is applicable only if all poles of sF(s) lie in the:

    • A. Right half of s-plane
    • B. Left half of s-plane
    • C. Imaginary axis
    • D. Origin