Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 5th Sem 2151908 Control Engineering Previous Question Paper

Enrolment No.___________

**GUJARAT TECHNOLOGICAL UNIVERSITY**

**BE - SEMESTER? V EXAMINATION ? SUMMER 2020**

**Subject Code: 2151908**

**Date:02/11/2020**

**Subject Name: Control Engineering**

**Time: 02:30 PM TO 05:00 PM**

**Total Marks: 70**

**Instructions:**

**1. Attempt all questions.**

**2. Make suitable assumptions wherever necessary.**

**3. Figures to the right indicate full marks.**

**MARKS**

**Q.1 (a)**Define transfer function with example.

**03**

**(b)**Distinguish open loop and closed loop control system with example.

**04**

**(c)**Find transfer function with Block diagram reduction technique.

**07**

Figure : 1

**Q.2 (a)**Explain transfer function of feedback and feed forward loop.

**03**

**(b)**Write note on mason's gain formula.

**04**

**(c)**Determine C/R1 and C/R2 for system shown in Figure 2.

**07**

Figure : 2

**OR**

**(c)**Solve SFG in figure 3 with Mason's Gain Formula.

**07**

1

**Figure : 3**

**Q.3 (a)**Explain disadvantages of closed loop system.

**03**

**(b)**Explain Force-Voltage and Force-Current analogy.

**04**

**(c)**Define following terms in context with the transient response specifications of second

**07**

order system using neat sketch: Delay time, Rise time, Peak time, Maximum overshoot,

settling time.

**OR**

**Q.3 (a)**Discuss the types of inputs with examples.

**03**

**(b)**Explain the transient and steady state response of the system with neat sketch

**04**

**(c)**Discuss time response of Second order control system for unit step input and also discuss

**07**

effect of damping factor on time response of Second order control system.

**Q.4 (a)**Discuss the limitation of Routh criteria.

**03**

**(b)**Using Routh criterion, check the stability of system with characteristic equation

**04**

(s + 2) (s - 2)(s + j) (s - j) (s2 + s + 1) = 0

**(c)**Sketch the root locus of open loop transfer function of a control system is given

**07**

by G(s). H(s) =

(+6)(2+4+13)

**OR**

**Q.4 (a)**Explain the method of finding angle of departure from the complex pole in root

**03**

locus method.

**(b)**Using Routh criterion, discuss about the stability for the system having characteristics

**04**

equation is given as 3s7 +9s6 + 6s5+ 4s4 + 7s3 + 8s2+ 2s + 6 = 0

**(c)**Sketch the root locus of open loop transfer function of a control system is given

**07**

by G(s). H(s) = (+1)2

(+2)2

**Q.5 (a)**State advantages

of frequency response analysis.

**03**

**(b)**With the help of neat diagrams, explain how the direction control valves are classified

**04**

**(c)**Draw a neat sketch of a pneumatic PID controller, its block diagram and state the transfer

**07**

function for the same.

**OR**

**Q.5 (a)**Explain terms; stable system, unstable system, marginally stable system.

**03**

**(b)**With the help of necessary diagram, explain Pneumatic nozzle flapper amplifier.

**04**

**(c)**Draw the schematic diagram of Pneumatic PD controller. Explain its working and derive

**07**

its transfer function.

*****************

2

This post was last modified on 04 March 2021