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Sri Krishna Engineering College
Panapakkam, Chennai – 601 301.
Sri Krishna Engineering College
Panapakkam, Chennai – 601 301.
Department of Electrical and Electronics Engineering
Unit Test-I
Subject: EE2353 - HIGH VOLTAGE ENGINEERING
Class: 3 EEE
Date: 06.02.2013
Duration: 1h 30 min
Max Marks: 50
Department of Electrical and Electronics Engineering
Unit Test-I
Subject: EE2353 - HIGH VOLTAGE ENGINEERING
Class: 3 EEE
Date: 06.02.2013
Duration: 1h 30 min
Max Marks: 50
Part – A (10 x 2 = 20)
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Part – A (10 x 2 = 20)
Why is high voltage preferred for transmission of long distance?
What is surge arrester?
Name the sources of switching surges.
What are the limitations of EHVAC transmission?
What is counter poise wire? Give its use.
What are the types of faults that may occur in power lines?
Define indirect stroke.
What is known as Isokeraunic Level?
Define Shielding Angle.
Define surge impedance of transmission line.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Why is high voltage preferred for transmission of long distance?
What is surge arrester?
Name the sources of switching surges.
What are the limitations of EHVAC transmission?
What is counter poise wire? Give its use.
What are the types of faults that may occur in power lines?
Define indirect stroke.
What is known as Isokeraunic Level?
Define Shielding Angle.
Define surge impedance of transmission line.
Part – B (2x 15 = 30)
11.
Part – B (2x 15 = 30)
(a) (i) Briefly discuss the vertical Syllabus of Over voltages in Electrical
Power Systems
[8]
(ii) Explain the lightning phenomena with respect to over voltages on a
transmission line.
[7]
Or
(ii) Derive mathematical model for lightning.
12.
11.
[7]
(a) (i) Explain different methods employed for lightning protection of
overhead lines.
(ii) A 3 phase single circuit transmission line is 400km long. If the line
is rated for 220 kv & having R of 0.1Ω / km L=1.26mH / km &
C=0.009 µF /km. Find 1)surge Impedence 2) velocity of propogation
neglecting resistance of line. If surface of 150kv(infinitely long tail)
strikes at one end of the line, what is the time taken for the surge to
the other end of line?
[5]
Or
(b) (i) Write short note on Simpson’s Theory
(ii) Derive mathematical model for lightning.
12.
[10]
[5]
(a) (i) Briefly discuss the vertical Syllabus of Over voltages in Electrical
Power Systems
[8]
(ii) Explain the lightning phenomena with respect to over voltages on a
transmission line.
[7]
Or
[7]
(a) (i) Explain different methods employed for lightning protection of
overhead lines.
[10]
(ii) A 3 phase single circuit transmission line is 400km long. If the line
is rated for 220 kv & having R of 0.1Ω / km L=1.26mH / km &
C=0.009 µF /km. Find 1)surge Impedence 2) velocity of propogation
neglecting resistance of line. If surface of 150kv(infinitely long tail)
strikes at one end of the line, what is the time taken for the surge to
the other end of line?
[5]
Or
(b) (i) Write short note on Simpson’s Theory
[5]
(ii)Two substations A,B are shown in figure. The attenuation factor is taken
as 0.9 and 0.8. Draw bewley lattice diagrams.
[10]
(ii)Two substations A,B are shown in figure. The attenuation factor is taken
as 0.9 and 0.8. Draw bewley lattice diagrams.
[10]
Prepared By
Prepared By
P.Vivek/AP/EEE
Verified By
D.Buvana/HoD/EEE
P.Vivek/AP/EEE
Verified By
D.Buvana/HoD/EEE
Sri Krishna Engineering College
Panapakkam, Chennai – 601 301.
Department of Electrical and Electronics Engineering
Unit Test-I
Subject: EE2353 - HIGH VOLTAGE ENGINEERING
Class: 3 EEE
Date: 06.02.2013
Duration: 1h 30 min
Max Marks: 50
Sri Krishna Engineering College
Panapakkam, Chennai – 601 301.
Department of Electrical and Electronics Engineering
Unit Test-I
Subject: EE2353 - HIGH VOLTAGE ENGINEERING
Class: 3 EEE
Date: 06.02.2013
Duration: 1h 30 min
Max Marks: 50
Part – A (10 x 2 = 20)
Part – A (10 x 2 = 20)
1.
Mention the causes for internal over voltages and give their approximate
magnitude & frequency
2. Draw and define impulse voltage wave shape and mention it’s specification as
per standards.
3. Define the uniform and non-uniform field.
4. A transmission line of surge impedance 250 is connected to a cable of surge
impedance 50 at the other end, if a surge of 400 kV travels along the line to the
junction point, find the voltage build at the junction.
5. How can the tower footing resistance can be varied?
6. What are the advantage of valve type arrester?
7. Why a simple spark gap cannot offer full protection against over voltages?
8. Define Thunderstorm Days
9. Compare HVDC & EHVAC with respect to economics of power transmission.
10. Name some HVDC systems.
Part – B (2x 15 = 30)
1.
Mention the causes for internal over voltages and give their approximate
magnitude & frequency
2. Draw and define impulse voltage wave shape and mention it’s specification as
per standards.
3. Define the uniform and non-uniform field.
4. A transmission line of surge impedance 250 is connected to a cable of surge
impedance 50 at the other end, if a surge of 400 kV travels along the line to the
junction point, find the voltage build at the junction.
5. How can the tower footing resistance can be varied?
6. What are the advantage of valve type arrester?
7. Why a simple spark gap cannot offer full protection against over voltages?
8. Define Thunderstorm Days
9. Compare HVDC & EHVAC with respect to economics of power transmission.
10. Name some HVDC systems.
Part – B (2x 15 = 30)
11. (a) (i) Briefly discuss the vertical Syllabus of Over voltages in Electrical Power
Systems
[8]
(ii) Explain different theories of charge formation in clouds.
[7]
Or
11. (a) (i) Briefly discuss the vertical Syllabus of Over voltages in Electrical Power
Systems
[8]
(ii) Explain different theories of charge formation in clouds.
[7]
Or
(b) Write short notes on:
(i) Rod gaps used as protective devices
(ii) Ground wires for protection of overhead lines.
[7]
12. (a)(i) What are the causes for power frequency over voltage? How they are
controlled in power systems?
[7]
(ii) An underground cable of inductance 0.150 mH/km and of capacitance 0.2
µF/km is connected to an overhead line having an inductance of 1.2 mH/km and
capacitance of 0.006 µF/km. Calculate the transmitted and reflected voltage and
current waves at the junction, if a surge of 200 kV travels to the junction, (1)
along the cable and (2) along the overhead line.
[8]
Or
(b) Write short notes on:
(i) Rod gaps used as protective devices
(ii) Ground wires for protection of overhead lines.
[7]
12. (a)(i) What are the causes for power frequency over voltage? How they are
controlled in power systems?
[7]
(ii) An underground cable of inductance 0.150 mH/km and of capacitance 0.2
µF/km is connected to an overhead line having an inductance of 1.2 mH/km and
capacitance of 0.006 µF/km. Calculate the transmitted and reflected voltage and
current waves at the junction, if a surge of 200 kV travels to the junction, (1)
along the cable and (2) along the overhead line.
[8]
Or
(b) (i) Draw & Explain the procedure to draw Bewley Lattice Diagram for a two
substations system .
[10]
(ii) Explain briefly about expulsion type arrester.
[5]
(b) (i) Draw & Explain the procedure to draw Bewley Lattice Diagram for a two
substations system .
[10]
(ii) Explain briefly about expulsion type arrester.
[5]
Prepared By
P.Vivek/AP/EEE
Verified By
D.Buvana/HoD/EEE
Prepared By
P.Vivek/AP/EEE
Verified By
D.Buvana/HoD/EEE