GIS Major Component are Circuit Breaker,
Isolator(Disconnecting Switch), Earthing Switch, Bus bar and connectors,
Current Transformer, Voltage Transformer, Gas filing and evacuating equipment.
Circuit Breaker:
Sulphur Hexafluoride(SF6) gas is used for arc quenching medium in this breaker.
Why SF6 is used, we all know about the properties of SF6 gas. It is an
electronegative gas and a strong tendency to absorb free electrons. Here, I
want to discuss about CB operation and controlling. CB operation can be carried
out either mechanically or electrically from the mechanism. It can be operated
from LCC Panel, Bay Control Unit (BCU), SCADA, and from control center. It
depends on the LOCAL/REMOTE Switch. CB has two springs: tripping spring and
closing spring.
CB Open Condition: Closing Spring charged condition and
Tripping Spring in Discharge Condition.
CB Close Condition: Closing Spring in discharged condition
and Tripping Spring in charge Condition.
Substation operation Mechanism of CB is various types like
Hydraulic, Pneumatic, Spring, Solenoid mechanism, Hydraulic/Spring Mechanism.
Isolator: It’s
operation on no load condition and Interlock with the relative CB and Earthing
Switch.
To be continued…..
