substation basic concepts

1.                                                                                          Substation

Indoor Substation:  A substation in which equipments are equipped  inside the substation building is called Indoor Substation. this  substation is used a voltage level 11kv,but surrounding air is contaminated metal corroding gases and fumes, conduct dust that raised a voltage up to 33kv to 66kv.

Indoor substation are two main compartments;

1.       Controlling compartment (indicating and metering)

2.       Protecting compartment (bus bar and electrical transformer)

3.       Outdoor substation:  A substation in which used to voltage level  55 kv  to 165 kv is called outdoor substation.

It divides two parts :

1.Pole Mounted Substation:  A substation which equipments are use of over head transmission line is called pole mounted substation its cost is cheapest, smallest and simple. Triple pole mechanically switch (T.P.R.O) is used for on /off purpose.4 pole is must be needed for this substation.

2.       Foundation Mounted substation:  In Foundation Mounted  Substation all the equipment area combined and the substation strung by the defense for safety purpose. The equipment required for such type of substation  heavy; must have good path for heavy transport.

2.Draw and explain the connection diagram double bus bar scheme?

·         In this scheme, Double breaker is used each ckt and each ckt is connected to both bas bar , Bus bar-1 and Busbar-2

Although in this scheme is very costly, yet it required best maintainese facility for the ckt breaker. When one ckt breaker is being opened and repaired for useful checks, the loads are automatically shifted other ckt breaker  easily.

Difference Between indoor and outdoor substation:

Outdoor Substation	Indoor Substation
1.Space required more.	1. Space required less.
2.Time required for errection less.	2. Time required for errection more
3. Future expansion easy.	3. Future Expansion Difficult.
4.Capital cost low.	4. Capital cost is High.
5.its operation difficult.	5.its operation Easyer.
6. It may be held open air in all kind of weather,	7.it may be held closed in atmosphere.

TYPES OF INDOOR SUBSTATION IMAGES