An ideal PID controller has the transfer function [1 + (1/0.55) + 0.25]. The frequency at which the magnitude ratio of the controller is 1, is________________?

Related Mcqs:

1. In a closed loop system, the process to be controlled is an integrating process with transfer function 1/2s. The controller proposed to be used in an integral controller with transfer function 1/T1s. When a step change in set point is applied to such a closed loop system, the controlled variable will exhibit__________________?

   A. Overdamped response B. Underdamped response C. Undamped response D. Unstable response...

2. The transfer function for a PID controller is (where, η i is the integral (reset) time and ηD is the derivative time.) ?

   A. Kc(1 + ηis + ηD ). s B. Kc[1 + (1/ηis) + ηD . s) C. Kc(1 + ηis + (1/ηD . s) D. None of these...

3. The frequency response of a dynamic element shows a constant magnitude ratio at all frequencies. The element exhibits a negative phase shift at all frequencies. The absolute value of the phase shift increases linearly with frequency. The element has the transfer function ?

   A. e-ηS B. (T1S + 1)/(T2S + 1) C. (T1S/(T2S + 1) D. (T1S + 1)/(T2S...

4. Find the ultimate gain and frequency for a proportional controller in the case of a process having the transfer function Gp(s) = 1/(4s + 1)(2s + 1)(s + 1) ?

   A. w = 1/√14, Kc = 45/7 √14 B. w = √(7/6), Kc = 46/3 C. w = 1, Kc = 13 D. w = √(7/8), Kc = 45/4...

5. The transfer function for an ideal proportional plus reset controller (reset time T) is_______________?

   A. Kc[1 + (1/TS)] B. Kc(1 + TS) C. Kc/(1 + TS) D. Kc/[1 + (s/T)]...

6. The transfer function for a P-D controller is________________?

   A. Kc(1+ηD s) B. Kc(1 +1/ηD s) C. Kc ηD s D. Kc/ηD s...

7. Suppose that the gain, time constant and dead time of a process with the following transfer function: Gc(s) = 10 exp( – 0.1s)/(0.5s + 1) are known with a possible error of ± 20% of their values. The largest permissible gain Kc of a proportional controller needs to be calculated below taking the values of process gain, time constant and dead time as________________?

   A. 8, 0.6, 0.08 B. 12, 0.6, 0.12 C. 8, 0.6, 0.12 D. 12, 0.4, 0.08...

8. The experimental response of the controlled variable y(t) for a step change of magnitude ‘P’ in the manipulated variable x(t) is shown below: The appropriate transfer function of the process is_________________?

   A. (Q/P) e-(Q/R)S/(TdS + 1) B. (Q/R) e-TdS/(Q/P) (S + 1) C. (Q/P) e-TdS/(Q/R) (S + 1) D. (Q/R) e-(P/Q)S/(TdS + 1)...

9. According to Bode stability criterion, a system is unstable, if the open loop frequency response exhibits an amplitude ratio exceeding unity at frequency for which phase lag is_________________?

   A. 0° B. 45° C. 90° D. 180°...

10. The frequency at which maximum amplitude ratio is attained is called the ______________ frequency?

    A. Corner B. Resonant C. Cross-over D. Natural...