BTS (C) VI (S) 10 043 Q

B. Tech Degree VI Semester (Supplementary)ExaminationSeptember 2010

EE 601 POWER SYSTEM - I(2006 Scheme)

Time : 3 Hours Maximum Marks : 100

PART - A(Answer ALL questions)

(8 x 5 = 40)

1. (a) Compare between Kaplan turbine and Francis turbine.Explain the significance of load factor and diversity factor of a power system.What is a stringing chart? What is its use?What is string efficiency of insulators? List the different methods to improvestring efficiency.Draw the graphical representation of optimum conductor size from Kelvin's Law.List out the main differences between A.C., distribution and D.C. distribution.What are the advantages of bundled conductors over single conductors?Write short notes on transposition of conductors.

PART B(4 x 15 = 60)

II. (a) Draw the schematic diagram of a steam power plant. Explain its working in detail. (10)(b) The maximum demand of a power plant is 80 MW. The capacity factor is 0.5

and utilization factor is 0.8. Find load factor and annual energy production. (5)OR

111. Briefly explain the different types of Tariffs. (15)

(a) What are the factors affecting sag in an overhead line? (5)(b) A transmission line has a span of 150 m between level supports. Line conductor has

a cross sectional area of 1.25 cm2 and it weighs 1.0 Kg/m. If the breaking stress of aconductor is 4,200 Kg/cm 2, calculate the maximum sag for a safety factor of 4.Assume a maximum wind pressure of 100 Kg/m2 of projected surface. (10)

OR(a) What is corona? What are the factors which affect corona? Discuss the advantages

and disadvantages of corona. (10)(b) A 33 KV, 3 phase, 50 Hz underground line, 3.4 Km long uses three single core cables.

Each cable has a core diameter of 2.5 cm and the radial thickness of insulation is 0.6 cm.The relative permittivity of the dielectric is 3.1. Find the maximum stress andcapacitance of the cable. (5)

(P.T.O.)

2(a) Briefly explain various systems of A.0 distribution.(b) Show that for the transmission of power over a given length, power loss is proportional

to the square of transmission voltage and also inversely proportional to the square ofpower factor.

OR(a) Five lines A, B, C, D & E run to a common point 0. Find the potential of 0 and the

current leaving each supply point assuming that no current is tapped from point 0.Resistance of various sections and potentials of feeding points are shown below :

E 21C V VA-

2 5 V5 V

.7 3 L ., V Vi.)

2. 3,(b) Explain the importance of Energy management and Power quality in a power system.

(8)

(a) Derive the expression for inductance of three phase lines with equilateral spacing.(b) Calculate the loop inductance per Km of a single phase transmission line comprising

of two parallel conductors one metre apart and 1.25 cm in diameter. Also calculate thereactance of the transmission line. Frequency is 50 Hz.

OR(a) Derive the A B C D constants of a medium transmission line using nominal T method.

Assume localised capacitance.(b) What is a Synchronous Phase Modifier? What is its use in a transmission system?

(10)

(5)

(7)

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