Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 4th Sem 2141708 Control System Previous Question Paper

Seat No.: ________

Enrolment No.___________

**GUJARAT TECHNOLOGICAL UNIVERSITY**

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

**Subject Code: 2141708**

**Date:02/11/2020**

**Subject Name: Control System**

**Time: 10:30 AM TO 01:00 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)**Draw and explain block diagram of open loop control system with

**03**

suitable example.

**(b)**Enlist advantages and disadvantages of closed loop control system over

**04**

open loop control system.

**(c)**Find out transfer function of electrical lead network.

**07**

**Q.2 (a)**Define the following terms:

**03**

1. Gain 2. Characteristic Equation 3. Pole

**(b)**Find out inverse Laplace transform for F(s)= 4 .

**04**

(+1)

**(c)**Derive transfer function of field controlled dc motor.

**07**

**OR**

**(c)**Obtain FI and F V analogy for given mechanical network

**07**

**Q.3 (a)**Define following terms of Signal Flow Graph.

**03**

Node, Loop , Self Loop

**(b)**Derive state model for series RLC circuit.

**04**

**(c)**Write the rules for block diagram Reduction technique

**07**

**OR**

**Q.3 (a)**Define state transition matrix using equation.

**03**

**(b)**Draw the

step response of second order system for values of damping

**04**

ratio (i) 1 (ii) =1 (iii) 0< < 1 (iv) =0

**(c)**Obtain the overall transfer function using Mason's gain formula for the

**07**

signal flow graph shown in Fig.

1

**Q.4 (a)**What are the advantages of state variable analysis over classical

**03**

methods?

**(b)**Derive first order step response.

**04**

**(c)**The closed loop transfer function of a second order system is given by

**07**

100

() =

. Determine damping ratio, peak overshoot, settling

2+10+100

time, rise time, peak time.

**OR**

**Q.4 (a)**Define position error constant, velocity error constant , Acceleration

**03**

error constant.

**(b)**Explain standard test signals.

**04**

**(c)**6 + 45 + 34 - 162 - 64 - 48 = 0 Check the stability of the

**07**

given characteristic equation using R-H method.

**Q.5 (a)**What is M circle and N circles in Nyquist plot.

**03**

**(b)**Define the following terms with respect to frequency response (i) Gain

**04**

Margin (ii) Phase Margin (iii) Gain cross-over frequency (iv) Phase

crossover Frequency

**(c)**Draw the Bode plot for a system transfer function

**07**

G(s)H(s) =

100

.

(+1)(+2)

**OR**

**Q.5 (a)**Explain polar plot in brief.

**03**

**(b)**Explain Nyquist stability criteria in brief.

**04**

**(c)**Draw the root locus for the open loop transfer function of a unity

**07**

feedback control system is

G(s) =

(+6)(+9)

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

2

This post was last modified on 04 March 2021