ABCB(air blast circuit breaker)

ABCB ( Air Blast Circuit Breaker)

1. Course: Power System Protection
Course Code: EEE4277
Presented by:
Md. Tareq Hasan (ID-EEE233)
Ambarish Biswas (ID-EEE188)
Saifur Rahaman Russel (ID-EEE189)
Md. Rumon Shaharier (ID-EEE186)
Md. Mahazuddin Sarkar (ID-EEE192)
Air Blast Circuit Breaker

2. OVERVIEW
INTRODUCTION
CLASSIFICATION
CONSTRUCTION
OPERATION
ADVANTAGE
DISADVANTAGE
APPLICATIONS
FUTURE PERSPECTIVE

3. INTRODUCTION
This type of breakers employ ‘air blast’ as the
quenching medium.
The contacts are opened by air blast produced by
the opening of blast valve.
The air blast cools the arc and sweeps away the
arcing products to the atmosphere.
This rapidly increases the dielectric strength of
the medium between contacts and prevents from
re-establishing the arc.
So the arc is extinguished and the flow of current
is interrupted.

4. CLASSIFICATION
Types of Air Blast Circuit Breaker
(1). Axial-blast type
(2). Cross-blast type
(3). Radial-blast type

5. 1.Axial-blast type:-
In which the air-blast is
directed along the arc
path as shown in Fig.

6. 2.Cross-blast type:-
In which the air-blast is
directed at right angles
to arc path as shown in
Fig.

7. 3.Radial-blast type:-
In which the air-blast is
directed radialy as shown
in Fig.

8. 1.AXIAL BLAST ABCB

9. 2.CROSS BLAST ABCB

10. CONSTRUCTION
In air blast circuit breaker (also called
compressed air circuit breaker) high
pressure air is forced on the arc through
a nozzle at the instant of contact
separation. The ionized medium between
the contacts is blown away by the blast
of the air. After the arc extinction the
chamber is filled with high pressure air,
which prevents restrike. In some low
capacity circuit breakers, the isolator is
an integral part of the circuit breaker.
The circuit breaker opens and
immediately after that the isolator
opens, to provide addition gap.

11. OPERATION

12. Advantages
The risk of fire is eliminated.
The arcing products are completely removed by
blast.
The growth of dielectric strength is so rapid that
final contact gap needed for arc extinction is very
small. This reduces the size of device.
The arcing time is very small due to the rapid
build up of dielectric strength between contacts.
Due to lesser arc energy, ABCB are very suitable
for conditions where frequent operation is requised.

13. Disadvantages
Air has relatively inferior arc extinguishing
properties.
Air blast circuit breakers are very sensitive to the
variation is the rate of restriking voltage.
Considerable maintenance is required for the
compressor plant which supplies the air blast.

14. Application
The air blast circuit breakers are finding wide
applications in high voltage installations. Majority
of the circuit breakers for voltages beyond 110kV
are of this type.

15. Future perspectives
In the near future, present interrupting
technologies can be applied to circuit-breakers with
the higher rated breaking currents (63kA to 80kA)
required in some networks with increasing power
generation.

16. Thank you