High Voltage Switchgear
we all are know the electrical voltages are classified into 3 types. low voltage, medium voltage and high voltage. the voltages from 0 to 1000v its called low voltage and voltage from 1000v to 36000v its called medium voltage and above 36000 volt its called high voltage. for handling this high voltage is not easy task. because the switching operation of these high voltage will chance for making flashover. that’s why handling these high voltages with safety manner the high voltage switchgear are used. the high voltage switchgear consists of circuit breaker for switching operations, control relays for protection and auto/manual control switches, breaker open and close controls are there. some times that high voltage switchgears keep it for on/off long time duration. so that time it produced high quenching and arc operations that’s controlled by highly designed circuit breakers. mostly ABB, OCB and SF6 circuit breakers used in the high voltage switchgears.
Switchgear breaker types:
Generally VCB Vacuum circuit breaker is not used in the high voltage switchgears because the vacuum circuit breakers does not having that much capability to handling that high voltage short circuit current. that’s why mostly prepared sulfur hexa fluoride SF6 circuit breakers. because SF6 circuit breaker gas working as a arc quenching medium. whenever the circuit operate that high current arc can be controlled by these gas quenching medium. there are two different types of SF6 circuit breakers there.
- single pressure SF6 circuit breaker
- double pressure SF6 circuit breaker
compared to other circuit breaker this SF6 circuit breaker having lot of advantages. the SF6 circuit breaker having gas that hexa fluoride is having less impact to environment. so it will not pollute the environment. the maintenance of SF6 circuit breaker is very less compared to other circuit breaker.
Air blast circuit:
Another mostly used high voltage switchgear circuit breaker is Air blast circuit breaker. the ACB circuit breaker the compressed air act as arc quenching medium. when ever the breaker operated that produced arc could be controlled by this compressed air quenching medium.
Oil circuit breaker:
the oil circuit breaker also widely used high voltage switchgear circuit breaker. here oil is used for arc quenching medium. there are two types of oil circuit breaker is there.
- Minimum oil circuit breaker (MOCB)
- Bulk oil circuit breaker (BOCB)
High voltage switchgear types:
the types of high voltage switchgear is classified based on the uses. there are two types of high voltage switchgears are there.
- Indoor high voltage switchgear
- Outdoor high voltage switchgear
Indoor high voltage switchgear:
Mostly indoor high voltage switchgear used gas insulated circuit breaker. that is SF6 circuit breaker
Outdoor high voltage switchgear:
Mostly outdoor high voltage switchgear used air compressed circuit breaker. that is air blast circuit breaker