Shivaji University 2011-5th Sem B.E T.E(Electrical)- (New), Power System Analysis - Question Paper
This is repeater paper of Power system analysis for 3rd year electrical engineering.
N - 625
Seat
No.
T.E. (Electrical) (Semester - V) (New) Examination, 2011 POWER SYSTEM ANALYSIS
Day and Date : Tuesday, 10-5-2011 Total Marks : 100
Time : 10.00 a.m. to 1.00 p.m.
Instructions : 1) Attempt any three questions from each Section.
2) Assume suitable data if necessary and state clearly the same,
3) Figures to the right indicate full marks.
SECTION - I
1. A) Derive an expression for the flux linkage :
i) due to single current carrying conductor
ii) in parallel current carrying conductors. 8
B) A single-phase line has two parallel conductors 3 m apart. The radius of each conductor is 1.0 cm calculate :
a) the loop inductance of the line / km.
b) inductance and capacitance of each conductor./ km. 8
2. A) Explain theory of formation of corona. Also explain the terms critical disruptive
voltage, critical visual voltage. 8
B) A three phase overhead transmission line is being supported by the three disc suspension insulators, the potentials across the first and second insulators are 8 KV and 11 KV respectively. Calculate :
a) the line voltage
b) the ratio of capacitance between pin and earth to self capacitance of each unit,
c) the string efficiency. 8
3. A) Draw the single line diagram of a typical power system and discuss various
power system elements. 8
B) Explain different types of conductor materials used in power system. 8
4. Write a short notes (any three):
a) Ring main A.C. distribution system
b) Skin and proximity effect
c) Different line supports
d) Pin type Insulators.
SECTION - II
5. A) Derive expression for sending end voltage for a short transmission line with
the vector diagram.
B) Find the sending end voltage and voltage regulation of a 250 Km, three phase, 50 Hz, transmission line delivering 25 MVA at 0.8 lagging power factor to a balanced load at 132 KV. The line conductors are spaced equilaterally 3 m apart. The conductor resistance is 0.11 ohm/Km and its effective diameter is 1.6 cm. Neglect leakance. Use the nominal-?: method.
6. A) Explain capacitance grading method of cable grading.
B) Discuss different methods of laying underground cables.
7. A) Formulate YBUS matrix of given four bus system in fig. (a). Whereas line
reactances are indicated in p.u.
B) Explain load flow analysis using Gauss-Siedel method.
8. Write a short notes (any three) :
1) Ferranti effect and Tuned power lines
2) Synchronous phase modifiers
3) Phase advancers
4) Belted cables.
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Attachment: |
| Earning: Approval pending. |
