Sri Venkateswara Institute of Medical Sciences (SVIMS) 2007 B.Tech Electrical and Electronics Engineering power systems-1 - Question Paper

4. (a) explain the design of primary distribution system with respect to sze of feeders. ( seven marks)
(b) discuss kinds of secondary distribution systems with neat diagrams. (13 marks)
Unit - 3
5.(a) explain the main Ewuipment used in substations.(10 marks)
(b) Draw neatly the Key diagram of a typical primary subtation.
( 10 marks)
or
6. (a) elaborate the methods of eualizing the potential in overhead line Insulators. (8 marks)
(b) A three phase 66 Kv transmission line is carried b strings of five suspension insulators. The capacity of every unit insualtor to the capacity relative to earth is 4:1. Cla culate the potential across every unit and the string efficiency.( presume that thre is no leakage). (10 marks)
unit - four
7. (a) Derive an expression for the capcitance of a simple core cable. (8 marks)
(b) A single core cable has an inner diameter of five cms and a core diameter of 1.5 cm. its paper dielectric has a working maximum dielectric stress 60 KV/ cm. compute he maximum permissible line voltage when such cables are used on a three phase system.
(12 marks)
or
8.(a) What is the most general criterion for classification of cables? Draw the skstch and labe the different parts of a single core low tension cable. (10 marks)
(b) A length of 3- core , 3phase metal sheathed cable gave the subsequent outcomes on test for capacitance: (i) Capacitance ranging from bunched condutors and sheath is µF.(ii) Capacitance ranging from 2 conductors bunched with sheath and the thrid conductor is 0.6 µF. with the sheath isolated , obtain the capacitance ( a) ranging from 2 conductors and (b) ranging from any 2 bunched conductors and the 3rd conductor. (10 marks)
Unit - 5
9. (a) provide brief description of corona phenomenon. ( eight marks)
(b) Derive the expression petential gradient at the surface of a conductor 1- phase transmission line. (12 marks)
or
10. (a) Clearly discuss what is meant by GMR and GMD of a transmisson line . (6 marks)
(b) What is equivalent spacing of a 3-phase line? What is its significance? (6 marks)
(c) compute the inductance of every conductor in a 3-phase, three wore system when the conductors are organizes horizontally with spacing such that = 4m ;= 3m ; = 2m.The conductors are trasposed and every has a diameterof 2.5 m. (8 marks)

Earning:   Approval pending.