What is SF6 gas? Why is it Used?

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SF6 gas is known as Sulphur Hexafluoride gas. This gas is used to extinguish the arc because it is an excellent dielectric, arc quenching, and has chemical and other physical properties, making it superior to other arc quenching mediums such as oil or air. Due to this reason, it is called a circuit breaker.

The SF6 circuit breaker is mainly divided into three types :

* Non-puffer piston circuit breaker.
* Single-puffer piston circuit breaker.
* Double-puffer piston circuit breaker.

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What are the advantages of VSCF wind electrical system?

Advantages of VSCF wind electrical system are :

* No complex pitch changing mechanism is needed.
* Aero turbine always keeps going at maximum efficiency point.
* Extra energy in the high wind speed region of the speed – duration curve can be extracted
* Significant reduction in aerodynamic stresses, which are associated with constant – speed operation.

Why electricity in India is in the multiples of 11 like 11kv, 22kv, 33kv?

Transformer Induced voltage equation contains 4.44 factor.

E=4.44*f*T*phi
E -Induced emf per phase
T -number of turns
f -frequency
phi -maximum flux per pole
From the equation we see that E is proportional to 4.4 and it is in turn multiple of 11.

So always transmission voltage is multiple of 11