electrical power substation | substation

Introduction

The nation’s power system is comprised of quite nineteen,000 generators, 642,000 miles of highvoltage transmission lines, and 6.3 million miles of distribution lines, serving a hundred forty five million customers.1 Within this expansive system, there area unit over fifty five,000 transmission substations and thousands a lot of of alternativetypes that function the vital interconnection points between generation, transmission, distribution, andcustomers (pic: 1). Given the ever present nature and importance of substations, development of advanced substation technologies presents an amazing chance to enhance the electrical grid’s responsibility,resiliency, efficiency, flexibility, and security, through new practicality, new topologies, and increased control of power flow and voltage.

The electrical station is that the part of an influence system during which the voltage is reworked from high to low or low to high for transmission, distribution, transformation, and shift. the ability electrical device, fuse, bus-bar, insulator, spike suppressor ar the most parts of associate degree electrical station.

Single Line Diagram of an Electrical Substation

The single line diagram of the substation is shown in the figure below. The connection of the substation is divided as

Outgoing feeder for feeding the other subsequent substations or switchgear.
Power transformer connection.
Voltage transformer connection for control and metering.
Incoming or power feeder connection

Nowadays the power demand is increasing terribly quickly. For fulfilling these Brobdingnagian power demands the trendy time needs the creation of larger and greater power generating stations. These power generating stations could also be hydro-electric, thermal or atomic. relying upon the provision of resources these stations area unit made completely different places. These places might not be nearer to load centers wherever the particular consumption of power takes place.
So it’s necessary to transmit these Brobdingnagian power blocks from generating station to their load centers. Long and high voltage transmission networks area unit required for this purpose. Power is generated relatively at the low voltage level. it’s economical to transmit power at a high voltage level. Distribution of power is finished at lower voltage levels as such as by customers. For maintaining these voltage levels and for providing larger stability variety of transformation and switch stations have to be compelled to be created between generating station and client ends. This transformation and switch stations area unit typically called electrical substations. relying upon the needs, the substations could also be classified as-

The fuse is connected between the bus-bar and every incoming and outgoing circuit. The isolator is provided on all sides of the fuse. this electrical device is employed for measure and protection. this transformers area unit placed on each side of the fuse so the protection zone is overlapped and canopy the fuse. The potential electrical device is connected to the bus bar and on the incoming line facet. Lightning or surge constraint area unit connected section to ground at the incoming line because the initial equipment and additionally at the terminal of electrical device and capacitance bank, the terminal of shunt reactor and a terminal of the generator, the terminal of the big motor to divert shift.

Step Down station
The stepped-up voltages should be stepped down at load centers, to totally different voltage levels for various functions. relying upon these functions the step-down station are more classified in several subclasses

Step Up station
Step up substations are related to generating stations. Generation of power is prescribed too low voltage levels because of limitations of the rotating alternators. These generating voltages should be stepped up for economical transmission of power over long distance. thus there should be an accelerate station related to generating station.

Indoor station The station is made underneath the roof is termed indoor kind substation. Generally, eleven kV and generally thirty-three kV station ar of this sort.

Outdoor kind station The outdoor kind station is made within the outdoors. Nearly all 132KV, 220KV, 400KV station are out of doors kind station. though today special GIS (Gas insulated substation) is made for an additional high voltage system that is mostly set underneath the roof.

Pole Mounted Substation

Pole mounted station area unit chiefly distribution station made on 2 poles, four poles and someday six or a lot of poles structures. In these sort of station, fuse protected distribution electrical device area unit mounted on poles at the side of electrical isolator switches.

Underground station
The station ar settled at underground is named underground station. In full places wherever place for constructing distribution station is troublesome to search out-out, one will choose the underground station theme.

Mobile station
The mobile stations also are terribly special purpose substation briefly needed for construction purpose. for large construction purpose, this station fulfills the temporary power demand throughout construction work.
Depending upon the constructional feature classes of the station could also be divided into the following manner-

Distribution station
Distribution station area unit settled wherever the first distribution voltages area unit stepped right down to offer voltages for feeding the particular customers through a distribution network.

Bulk offer or Industrial station
Bulk offer or industrial station area unit typically a distribution station, however, they’re dedicated for one shopper solely. Associate in Nursing industrial shopper of enormous or medium offer cluster could also be selected as bulk offer shopper. Individual step down station is devoted to those customers.

Mining station
The mining station area unit terribly special sort of station and that they would like special style construction thanks to additional precautions for safety required within the operation of the electrical offer.