MODEL QESTION PAPER
Fourth Semester Diploma Examination
ELECTRICAL BOARD
TRANSMISSION AND DISTRIBUTION
TIME: 3 Hours Max Marks: 100
Note: i) Section I is compulsory.
ii) Answer any six full questions taking two full questions
from each of the remaining sections.
SECTION -I
- a) Fill in the blanks with appropriate word / words : 5x1 = 5
i) The full form of SCADA is--------------
ii) Power loss will be minimum in a transmission line if the load P.F is ------------
iii) Voltage drop in cable system is ------------ than over head system.
iv) The location of lighting arrestor in sub-station is -------------
v) For balanced 3 phase 4 wire system ,the load current in the neutral is -----------
b) Explain indoor and outdoor type substation. 5
SECTION -II
2. a) Compare overhead system with underground system of transmission line. 8
b) A single phase transmission line transmitting 1000 KW power to a factory at 11 KV at
0.8 Power factor lag has a loop resistance of 2 Ω and reactance of 3 Ω. Determine
sending end voltage and % regulation. 5
c)List any two advantages of AC transmission line. 2
3. a) Draw and explain vector diagram for short transmission line. 8
b) List the merits and demerits of direct laying of UG cable. 5
c) Name the classifications of UG cables. 2
4. a) Explain different transmission system. 8
b) Explain the meaning of corona. 5
c) List the factors affecting corona. 2
SECTION – III
5. a) Explain the procedure for erection of steel towers. 8
b) Explain the maintenance of overhead transmission line. 5
c) List the materials used for line supports. 2
6. a) Explain double bus double breaker type bus bar arrangement with a neat diagram 8
b) Explain the maintenance of station transformer. 5
c) State the meaning of receiving station. 2
7. a) Explain the main components of HVDC transmission system. 8
b) List the different types of fact controllers. 5
c) List the various units of substation. 2
SECTION – IV
8. a) Explain feeder, distributor and service main in distribution system. 8
b) Explain voltage drop in feeders. 5
c) State the difference between 3 wire and 4 wire distribution system. 2
9. a) Explain the different methods of protection against lightning. 8
b) Explain horn gap type lighting arrestor. 5
c) Define voltage surge. 2
10. a) Explain the need for distribution automation. 8
b) Write a note on SCADA system. 5
c) List the objectives of distribution automation. 2