PART ( I )
The Breakdown in Gases
Experiment No. 1
Breakdown in Uniform A.C. Fields (plane / plane)
The purpose of the experiment is to find the breakdown characteristics of the
air in uniform A.C. fields. For plane to plane electrodes.
10MΩ
100pF
(b)
H.V.
(d)
V
(a)
0 - 220 V
(c)
~
figure (1)
(a): High voltage Auto transformer.
(b): High voltage resistance .
(c): Electrodes .
(d): Capacitive divider.
Procedure:
1. Connect the circuit as shown in figure (1).
2. With plane / plane connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3) and run (5).
2. Discuss the results.
)2(
Experiment No. 2
Breakdown in Uniform A.C. Fields (sphere / sphere)
The purpose of the experiment is to find the breakdown characteristics of the
air in uniform A.C. fields. For sphere to sphere electrodes
10MΩ
100pF
(b)
(d)
(a)
H.V.
V
0 - 220 V
(c)
~
Figure (2)
(a): High voltage Auto transformer.
(b): High voltage resistance .
(c): Electrodes .
(d): Capacitive divider.
Procedure:
1. Connect the circuit as shown in figure (2).
2. With sphere / sphere connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3) and run (5).
2. Discuss the results.
)3(
Experiment No. 3
Breakdown in Non-Uniform A.C. Fields (needle / plane)
The purpose of the experiment is to find the breakdown characteristics of the
air in non-uniform A.C. fields. For needle to plane.
10MΩ
100pF
H.V.
V
0 - 220 V
~
figure (3)
Procedure:
1. Connect the circuit as shown in figure (3).
2. With Needle / plane connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3).
2. Discuss the effect of non-uniform field on the breakdown characteristics of air.
3. comment on the results.
)4(
Experiment No. 4
Breakdown in Non-Uniform A.C. Fields (needle / sphere)
The purpose of the experiment is to find the breakdown characteristics of the
air in non-uniform A.C. fields. For needle to sphere electrodes.
10MΩ
100pF
H.V.
0 - 220 V
V
~
figure (4)
Procedure:
1. Connect the circuit as shown in figure (4).
2. With Needle / sphere connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3).
2. Discuss the effect of non-uniform field on the breakdown characteristics of air.
3. comment on the results.
)5(
Experiment No. 5
Breakdown in Uniform D.C. Fields (plane / plane)
The purpose of the experiment is to find the breakdown characteristics of the
air in uniform D.C. fields. For plane to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Cs
10000 pF
0 - 220 V
V
~
figure (5)
Procedure:
1. Connect the circuit as shown in figure (5).
2. With plane / plane connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3).
2. Comment on the results.
)6(
Experiment No. 6
Breakdown in Uniform D.C. Fields (sphere / sphere)
The purpose of the experiment is to find the breakdown characteristics of the
air in uniform D.C. fields. For sphere to sphere electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Cs
10000 pF
0 - 220 V
V
~
figure (6)
Procedure:
1. Connect the circuit as shown in figure (6).
2. With sphere / sphere connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3).
2. Comment on the results.
)7(
Experiment No. 7
Breakdown in Non-Uniform D.C. Fields (needle / plane)
The purpose of the experiment is to find the breakdown characteristics of the
air in non-uniform D.C. fields. For needle to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Cs
10000 pF
0 - 220 V
V
~
figure (7)
Procedure:
1. Connect the circuit as shown in figure (7).
2. With needle / plane connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3).
2. Comment on the results.
)8(
Experiment No. 8
Breakdown in Non-Uniform D.C. Fields (needle / sphere)
The purpose of the experiment is to find the breakdown characteristics of the
air in non-uniform D.C. fields. For needle to sphere electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Cs
10000 pF
0 - 220 V
V
~
figure (8)
Procedure:
1. Connect the circuit as shown in figure (8).
2. With needle / sphere connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3).
2. Comment on the results.
)9(
Experiment No. 9
Breakdown in Air at (Polarity Effect) Uniform D.C. Fields (plane / plane)
The purpose of the experiment is to find the breakdown characteristics of the
air in uniform D.C. fields. For plane to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Cs
10000 pF
0 - 220 V
V
~
figure (9)
Procedure:
1. Connect the circuit as shown in figure (9).
2. With plane / plane connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3).
2. Compare between the characteristics of polarity reversing and non-polarity
reversing.
3. Comment on the results.
)10(
Experiment No. 10
Breakdown in Air in (Polarity Effect) Uniform D.C. Fields (sphere / sphere)
The purpose of the experiment is to find the breakdown characteristics of the
air in uniform D.C. fields. For sphere to sphere electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Cs
10000 pF
0 - 220 V
V
~
figure (10)
Procedure:
1. Connect the circuit as shown in figure (10).
2. With sphere / sphere connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3).
2. Compare between the characteristics of polarity reversing and non-polarity
reversing.
3. Comment on the results.
)11(
Experiment No. 11
Breakdown of Air in Non (Polarity Effect) Non -Uniform D.C. Fields (needle / plane)
The purpose of the experiment is to find the breakdown characteristics of the
air in non-uniform D.C. fields. For needle to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Cs
10000 pF
0 - 220 V
V
~
figure (11)
Procedure:
1. Connect the circuit as shown in figure (11).
2. With needle / plane connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3).
2. Compare between the characteristics of polarity reversing and non-polarity
reversing.
3. Comment on the results.
)12(
Experiment No. 12
Breakdown of Air in Non (Polarity Effect) Non-Uniform D.C. Fields (needle / sphere)
The purpose of the experiment is to find the breakdown characteristics of the
air in non-uniform D.C. fields. For needle to sphere electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Cs
10000 pF
0 - 220 V
V
~
figure (12)
Procedure:
1. Connect the circuit as shown in figure (12).
2. With needle / sphere connection at air gap of 5 mm apart increase the voltage
until breakdown is occurred. Take the reading of the voltage.
3. Repeat run (2), with d=10mm, 15mm, 20mm, 25mm, 30mm.
Report:
1. Draw the breakdown voltage against the distance between electrodes for run
(2), run (3).
2. Compare between the characteristics of polarity reversing and non-polarity
reversing.
3. Comment on the results.
)13(
PART ( II )
The Breakdown in Liquids
)14(
Experiment No. 13
Breakdown in Liquids in Uniform A.C. Fields (plane / plane)
The purpose of the experiment is to find the breakdown characteristics of the
liquids in uniform A.C. fields. For plane to plane electrodes.
10MΩ
100pF
H.V.
Liquid
0 - 220 V
V
~
figure (13)
Procedure:
1. Connect the circuit as shown in figure (13).
2. With plane / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. Mention the main types of liquid isolators which are used in High voltage
equipments.
2. Discuss the results.
)15(
Experiment No. 14
Breakdown in Liquids at Non-Uniform A.C. Fields (needle / plane)
The purpose of the experiment is to find the breakdown characteristics of the
liquids in non - uniform A.C. fields. For needle to plane electrodes.
10MΩ
100pF
H.V.
Liquid
0 - 220 V
V
~
figure (14)
Procedure:
1. Connect the circuit as shown in figure (14).
2. With needle / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. Insert the best type of liquid isolator which are bearing the voltage breakdown.
2. Discuss the results.
)16(
Experiment No. 15
Breakdown in liquid at Uniform D.C. Fields (plane / plane)
The purpose of the experiment is to find the breakdown characteristics of the
liquid in uniform D.C. fields. For plane to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
Liquid
Cs
10000 pF
H.V.
0 - 220 V
V
~
figure (15)
Procedure:
1. Connect the circuit as shown in figure (15).
2. With plane / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. What are the main variations in the mechanism of liquids at using DC voltage.
2. Discuss the results.
)17(
Experiment No. 16
Breakdown in liquid at Non-Uniform D.C. Fields (needle / plane)
The purpose of the experiment is to find the breakdown characteristics of the
liquid in non-uniform D.C. fields. For needle to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Liquid
Cs
10000 pF
0 - 220 V
V
~
figure (16)
Procedure:
1. Connect the circuit as shown in figure (16).
2. With needle / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. What is the difference between using non-uniform and uniform DC field on
the mechanism of the liquids.
2. Discuss the results.
)18(
Experiment No. 17
Breakdown in liquid at (Polarity Effect) Uniform D.C. Fields (plane / plane)
The purpose of the experiment is to find the breakdown characteristics of the
liquid in uniform D.C. fields. For plane to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
Liquid
Cs
10000 pF
H.V.
0 - 220 V
V
~
figure (17)
Procedure:
1. Connect the circuit as shown in figure (17).
2. With plane / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. Compare the characteristics of polarity reversing with non-polarity reversing
at (plane \ plane).
2. Discuss the results.
)19(
Experiment No. 18
Breakdown in liquid at non (Polarity Effect) Non-Uniform D.C. Fields (needle / plane)
The purpose of the experiment is to find the breakdown characteristics of the
liquid in non-uniform D.C. fields. For needle to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Liquid
Cs
10000 pF
0 - 220 V
V
~
figure (18)
Procedure:
1. Connect the circuit as shown in figure (18).
2. With needle / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. Compare the characteristics of polarity reversing with non-polarity reversing
at (needle \ plane).
2. Discuss the results.
)20(
PART ( III )
The Breakdown in Solids
)21(
Experiment No. 19
Breakdown in Solids in Uniform A.C. Fields (plane / plane)
The purpose of the experiment is to find the breakdown characteristics of the
solids in uniform A.C. fields. For plane to plane electrodes.
10MΩ
100pF
H.V.
Solid
0 - 220 V
V
~
figure (19)
Procedure:
1. Connect the circuit as shown in figure (19).
2. With plane / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. Mention the main types of solid isolators which are used in High voltage
Equipments.
2. Discuss the results.
)22(
Experiment No. 20
Breakdown in Solids at Non - Uniform A.C. Fields (needle / plane)
The purpose of the experiment is to find the breakdown characteristics of the
liquids in non - uniform A.C. fields. For needle to plane electrodes.
10MΩ
100pF
H.V.
Solid
0 - 220 V
V
~
figure (20)
Procedure:
1. Connect the circuit as shown in figure (20).
2. With needle / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. Insert the best type of solid isolators which are bearing the voltage breakdown.
2. Discuss the results.
)23(
Experiment No. 21
Breakdown in Solids at Uniform D.C. Fields (plane / plane)
The purpose of the experiment is to find the breakdown characteristics of the
solids in uniform D.C. fields. For plane to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Solid
Cs
10000 pF
0 - 220 V
V
~
figure (21)
Procedure:
1. Connect the circuit as shown in figure (21).
2. With plane / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. What are the main variations in the mechanism of solid isolators at using DC
voltage .
2. Discuss the results.
)24(
Experiment No. 22
Breakdown in Solids at Non-Uniform D.C. Fields (needle / plane)
The purpose of the experiment is to find the breakdown characteristics of the
Solids in non-uniform D.C. fields. For needle to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Solid
Cs
10000 pF
0 - 220 V
V
~
figure (22)
Procedure:
1. Connect the circuit as shown in figure (22).
2. With needle / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. What are the difference between using non-uniform and uniform DC field on
the mechanize of the solid.
2. Discuss the results.
)25(
Experiment No. 23
Breakdown in Solids at (Polarity Effect) Uniform D.C. Fields (plane / plane)
The purpose of the experiment is to find the breakdown characteristics of the
solids in uniform D.C. fields. For plane to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
Solid
Cs
10000 pF
H.V.
0 - 220 V
V
~
figure (23)
Procedure:
1. Connect the circuit as shown in figure (23).
2. With plane / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. Compare the characteristics of polarity reversing with non-polarity reversing
at (plane \ plane).
2. Discuss the results.
)26(
Experiment No. 24
Breakdown in Solids at non (Polarity Effect) Non -Uniform D.C. Fields (needle / plane)
The purpose of the experiment is to find the breakdown characteristics of the
solids in non-uniform D.C. fields. For needle to plane electrodes.
10MΩ
RL=50 KΩ
140 MΩ
H.V.
Solid
Cs
10000 pF
0 - 220 V
V
~
figure (24)
Procedure:
1. Connect the circuit as shown in figure (24).
2. With needle / plane connection increase the voltage until breakdown is
occurred. Take the reading of the voltage.
Report:
1. Compare the characteristics of polarity reversing with non-polarity reversing
at (needle \ plane).
2. Discuss the results.
)27(
PART ( IV )
The Impulse
)28(
Experiment No. 25
Single Stage Impulse Generator
The purpose of the experiment is to measure the output impulse voltages of
the single – stage impulse generator.
Rd= 6100Ω
10MΩ
Cb
10000 pF
Re= 6100Ω
Cs
10000 pF
0 - 220 V
V
~
St 700
figure (25)
Procedure:
1. Connect the circuit as shown in figure (25).
2. Start increase the voltage unit breakdown of the sphere gap is occurs. The
distance between sphere gap is 10 mm measure the voltage.
3. Repeat run (2), at d=20mm, 25mm, and the measurements of voltage.
Report:
1.
2.
3.
4.
Discuss the functioning of single stage impulse generator.
Draw the equivalent circuit of single stage I.G.
Draw the waveform of single stage I.G.
Comment on the results.
)29(
Experiment No. 26
Multi - Stage Impulse Generator
The purpose of the experiment is to measure the output impulse voltages of
the Multi – stage impulse generator.
Rd= 375Ω
Cb
1200 pF
Re= 6100Ω
Cs
10000 pF
RL= 50KΩ
10MΩ
Cb
1200 pF
Rm= 140MΩ
Cs
10000 pF
0 - 220 V
St 700 V
~
Gm
figure (26)
Procedure:
1. Connect the circuit as shown in figure (26).
2. Start increase the voltage unit breakdown of the sphere gap is occurs. The
distance between sphere gap is 10 mm, 20mm.
Report:
1. Discuss the functioning of Multi - stage impulse generator.
2. Discus the main parts of the impulse waveform, then discuss how can be
controlled these parts.
3. Comment on the results.
)30(
References
1. The General administration for designing and developing the
curriculums, "High Voltage Technique", Handbook, all right received
to the general foundation for the technician education and vocational
trainings, KSA, 2003.
2. Amouri, F., "High Voltage Laboratory", signature, Electrical
engineering dept., University of Mosul, Iraq, 1985.
3. Gallagher T. J. & Pearmain A. J., "High Voltage testing and design",
Handbook, University of London, John Wiley, England, 1984.
4. Weedy B. M., "underground transmission of electric power",
Handbook, John Wiley, England, 1979.
)31(