Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU) B-Tech 6th Semester (Sixth Semester) 2015-2016 EEE 601 Power System Analysis Question Paper
(Following Paper H) and Roll No. to be ?lled in your
Answer Books)
RollNoLIllllLlIl
B. TECH.
Theory Examination (Semester-VI) 2015-16
POWER SYSTEM ANALYSIS
Time : 3 Hours Max. Marks : 100
Section-A
\
1. Attempt all parts. All parts carry equal marks. Write
answer of each part in short. (2X10 = 20)
(a) Represent the reactance diagram of a power system
with justi?cation.
(b) Show that
2
Kvw] x MVAW)
MVAW)
Z = Z x
M(neW) px(old) K
v(new)
(c) Derive the equation [YEW] = [A][Y][A]T using singular
trans?mnation.
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(d)
(e)
(f)
(g)
(h)
(1)
(i)
Discuss the signi?cance of Slack or Swing bus in case of
load ?ow study.
What are the assumptions made to make the load ?ow
equations decoupled?
Name the factors which a??ect the transient stability.
De?ne steady state and Transient stability in respect of a
power system. Also de?ne their stability limit.
A 50Hz four pole tutbogenerator rated 20MVA, 13.2KV
has an inertia constant (H) = 9.0kW-sec/KVA. Deter-
mine the kinetic energy stoped in the rotor.
Derive the expression of a transmission line for wave
propagation.
Discuss the propagation of a wave travelling along a
line and then enters the cable.
Section-B
2. Attempt any ?ve questions from this following.
(a)
(5x10 = 50)
Prepare a perphase schematic of the system shown in
Fig-l and show all impedences in per unit (p.u.) on a
lOOMVA, 32kV base in the transmission line circuit. The
necessary data for this problem are as follow :
(2)
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T1 T:
3? ?ween .??
G G 0 G.
?? ? (mason (20+j80) l ?? ?
??> Load
Fig. 1
G1 : SOMVA, 12.2kV, X = 0.15 p.u.
G2 : 20MVA, 13.8 kV, X = 0.15 p.u
Tl : 80MVA, 12.2/161kV, X = 0.10 p.u
T2 : 40MVA, 13.8/161kV, X = 0.10 p.u.
Load : SOMVA, 0.80 PF lagg, operating?at 154KV
Determine the impedance of the load for the load
modelled as a series combination of resistance and
inductance.
(b) Draw the sequence network connections for L?G fault
occurring in the network shown in F ig. 2 with proper
justi?cation.
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(c) (1) Discuss the 3-phase short circuit transient on a trans-
mission line.
(i1) Explain the terms (i) subtransient rmctance (xii) (ii)
transient reactance (x1) and synchronous reactance
for a synchronous machine.
(d) Draw the zero sequence network for the system shown
in ?g. (3). Assume zero sequence reactances for the
generator and motors of 0.06 pp. Current limiting
reactors of 2.5 ohms each are connected in the neutral
of generator and motor No. 2. The zero sequence
reactance of the transmission line in 300 ohm
Data : ?
G : 25MVA, llkV, X" = 20%; Ml: lSMVA, lOKV, x"
= 25%
M2 = 7.5 MVA, lOkV, x" = 25%
T1&T2: 30MVA, 10.8/121KV, X=10% each
?__?? I I it HDY
E I I it |??
g A/?S \S/A Motor
Fig.3
The series reactance of the line in 100 ohms.
Select the generator rating as base in the generator cir-
cuit.
(4)
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(e) Classify the buses for load ?ow study. Formulate the
load ?ow problem (in polar form) to be solved by
newton - Raphson method. Also discuss its solution
algorithm
(1) Derive Swing equation with the help of equal area crite-
rion. Discuss the case of occurrence of fault and is cleared
after some time with the help of equal area criterion.
(g) What are the various method of improving transient
stability? Discuss in brief.
(11) A surge of lSkV magnitude travels along a cable
towards a junction with an overhead line. The inductance
and capacitance of the cable and overhead line are
respectively 0.3 mH, 0.4pF and 1.5mH, 0.012p.F per
kilometre. Find the voltage at the junction due to this
surge.
Section-C
Note: Attempt any two questions from this section.
(2X15=30)
3. Discuss clearly the problem formulation and solution algo-
rithm for Fast decoupled method for load ?ow study of a
power system.
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4. The following in the system data for the load ?ow solution using
G-S method:
Line admittances :
Bus Cose
1-2 _.._.?__._>
1-3 ????)
2-3 ??.;
2-4 ??_>
3-4 ?__)
Admittance
2 -j 8.0
l - j 4.0
0.666 - j_2.664
l - j4.0
2- j8.0
The schedule of active and reactive powers :
Bus Cod
l
2
3
4
P
0.5
0.4
0.3
Q
0.2
0.3
0.1
V Remarks
1.06 slack
l+j0.0 RV; 0.25Q51.0
1+j0.0 P-Q
l+j0.0 P-Q
Determine the bus voltages at the end of ?rst iteration using
Gauss-Seidel method. Take acceleration factor 1.6.
5. Determine the critical clearing angle for the network shown
in ?g. 4. When the 3-phase fault occurs at B and the breakers
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(6)
A and B operates simultaneously. The generator is delivering 1.0
pg. before the fault tabes place.
jo.lZQ
V=1.0 L0_?
V=l.1p.p A B
Fig. 4
(7) P.T.O.
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This post was last modified on 29 January 2020