JNTU
JNTU B.Tech III CONTROL SYSTEMS Previous Question Paper (November/December - 2017 - R13)
Note: This question paper contains two parts A and B. Part A is compulsory which carries 25 marks. Answer all questions in Part A. Part B consists of 5 Units. Answer any one full question from each unit. Each question carries 10 marks.
Part A
Why is negative feedback invariably preferred in a closed loop system?
Answer
Negative feedback is preferred because it reduces system sensitivity to parameter variations, minimizes the effect of external disturbances, improves bandwidth, and enhances overall system stability by reducing the closed-loop gain.
Distinguish between open loop and closed loop system.
Answer
| Feature | Open Loop System | Closed Loop System |
|---|---|---|
| Feedback | Absent | Present |
| Complexity | Simple and inexpensive | Complex and costly |
| Accuracy | Depends on calibration | High due to error correction |
What are the applications of synchro?
Answer
Sign in to view the complete answer paper.
Write the importance of SFG in control systems.
Answer
Sign in to view the complete answer paper.
Define peak overshoot.
Answer
Sign in to view the complete answer paper.
What is the effect of P, PI controller on the system performance?
Answer
Sign in to view the complete answer paper.
How will you find root locus on real axis?
Answer
Sign in to view the complete answer paper.
Write the drawbacks of RH criteria.
Answer
Sign in to view the complete answer paper.
What are frequency domain specifications?
Answer
Sign in to view the complete answer paper.
Define Gain margin and Phase margin.
Answer
Sign in to view the complete answer paper.
Part B
Find the transfer function of the network given figure 1.
Answer
Sign in to view the complete answer paper.
Explain translatory and rotary elements of mechanical systems.
Answer
Sign in to view the complete answer paper.
What is feed back? Explain the effects of feedback.
Answer
Sign in to view the complete answer paper.
Obtain the transfer function X1(s)/F(s) for the mechanical system shown figure 2.
Answer
Sign in to view the complete answer paper.
Explain the rules for block diagram reduction technique.
Answer
Sign in to view the complete answer paper.
Derive the transfer function for armature controlled DC Servomotor.
Answer
Sign in to view the complete answer paper.
Reduce the given block diagram and hence obtain the transfer function (figure 3).
Answer
Sign in to view the complete answer paper.
Write the applications AC servomotor.
Answer
Sign in to view the complete answer paper.
Determine the error coefficients and static error for G(s)= 1 / [s(s+1)(s+10)], H(s) = s + 2.
Answer
Sign in to view the complete answer paper.
Find out the output of the undamped second order system when the input applied to the system is unit step input.
Answer
Sign in to view the complete answer paper.
The open-loop transfer function of a unity feedback system is given by G(s)= 500 / [s(1+0.1s)]. Find the peak overshoot and time peak overshoot. If peak overshoot is to be reduced by 20%, what is the change in the gain?
Answer
Sign in to view the complete answer paper.
Explain effects of proportional derivative and proportional integral controllers in system performance.
Answer
Sign in to view the complete answer paper.
How RH Stability criterion can be used to study the relative stability?
Answer
Sign in to view the complete answer paper.
Explain the effects of adding poles and zeros to G(s)H(s) on the root loci by considering one the example.
Answer
Sign in to view the complete answer paper.
Sketch the root locus plot of a unity feedback system whose open loop T.F is G(s) = [K(s2-2s+2)] / [(s+2)(s+3)(s+4)].
Answer
Sign in to view the complete answer paper.
Define i) Minimum phase transfer function ii) Non minimum phase transfer function.
Answer
Sign in to view the complete answer paper.
Enlist the steps for the construction of Bode plots.
Answer
Sign in to view the complete answer paper.
Sketch the Bode plots for a system G(s) = [15(s+5)] / [s(s2+16s+100)]. Hence determine the stability of the system.
Answer
Sign in to view the complete answer paper.