University of Mumbai 2007-5th Sem B.E Electrical and Electronics Engineering Control System-I - Question Paper

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\<c) MKe suuaoie assumption wherever required.

(3)    Attempt total five questions.

(4)    Figures to the right indicate marks.

f ertjSfcj.jb    CeryMoJ GrxfJ.3? f

1. (a) Find the transfer function    of a system having diffrential equation given below :    5

d¹c(1)

+ c(t) - 1 (t) + 2r(l - 1)

dr dt

(b) Find out the transfer Junction for the following network using signal flow graph.

(cj Estimate the step response of the system having following possible pole locations.

<r

(d) Show possible nature of polar plots for the systems having following transfer function.

k

(I) Q_a(s)-j

8 (1+ ST, )

(II) G_B(s)

(b) Compare block diagram reduction and signal flow graph reduction techniques explicitly.

3. (a) Find out the total response of the system in terms of steady state and transient response.

f 2ZI t

rr~ Mc-tj

i-J_S

Comment on the transient behaviour of the system if the input is scaled by A units i.e. A.U(t). Draw graphs for total responses.    (TURN OVER

|U1 '

transfer function

(b) For the unity feedback system having opne loop

k(s + 2)

G<s)

s s +7s +12s

Find ;

(i)    Type of tho system

(ii)    Static error coefficients

*2

(iii) Steady state error when input to the system is t¹

4. (a) Determine order and type of the system which are represented by block diagrams in figure.

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O)

C B)

(b) For a system with characteristic equation

F(s) * s² 4- 3s⁵ + 4s⁴ + 6s³ + 5s² + 3s + 2 * 0 examine stability.

5. (a) For a unity feed back system

800(8 4-2)

G<s) = -=-

s (s + 10)(s + 40)

Sketch the bode plot, asymptotic in nature comment on stability.

(b) Define the following terms j

(i)    Corner frequency    (Iv) Gain Margin

(ii)    Bandwidth    (v) Break away and entry points

(iii)    Phase Margin

6.    (a) Find the value of K which makes the system just oscillate given that

_G(s)=-iiiii)-

s(s + 2)(s + 4)(s + 8)($ + 10)

and also find the frequency of oscillations. Use polar plot for analysis.

(b) Draw the complete root locus for the

GH(s) --\-

s (s + 4 )(* +2s + 2)

Determine value of K for stability. Determine also oscillating frequency.

10

1

(a) Draw the signal flow graph for the following network and find the transfer function.

2

(d)    Effect of 5 on the magnitude plot for the quadratic poles of 2nd order system.

Attachment: university-of-mumbai-2007-b-e-electrical-and-electronics-engineering-51237-1.pdf

Earning:   Approval pending.