28-04-2011, 03:44 PM
PRESENTED BY:-
ATUL KUMAR SINHA
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WHAT IS a SWITCHYARD ?
Switchyard means collection of electrical equipment where high voltage electricity is switched using of various component.
Electrical switchyards are usually part of a substation where electricity is transformed from one voltage to another for the transmission, distribution.
POWER TRANSMITE FROM POWER STATION TO CUSTOMERS THROUGH SWICHYARD
CIRCUIT BREAKER
A circuit breaker is an automatically-operated electrical switch designed to protect an electrical circuit from damage caused by overload or short circuit.
Its basic function is to detect a fault condition and, by interrupting continuity, to immediately discontinue electrical flow.
It can make or break a circuit either manually or by remote under normal or fault conditions.
Actuator lever - used to manually trip and reset the circuit breaker.
Actuator mechanism - forces the contacts together or apart
Contacts - Allow current when touching and break the current when moved apart
Terminals
Bimetallic strip.
Calibration screw - allows the manufacturer to precisely adjust the trip current of the device after assembly.
Solenoid
Arc divider/extinguisher
USES OF CIRCUIT BREAKER
Circuit breaker are used for all type of voltage.
It is using in high power laboratories.
It is using outdoor as well as indoor protection.
CURRENT TRANSFORMER
CT is a type of instrument transformer that is used in power system for measurement, detection, protection the system.
Current transformers are used extensively for measuring current and monitoring the operation of the power grid.
Current transformers, together with voltage transformers (VT) (potential transformers (PT)), are known as instrument transformers.
it is a device used to measure large current by scaling large primary current to a smaller , easy to measure, secondary current.
USES OF CURRENT TRANSFORMER
Current Transformer are used for electronic meter whose VA are very less.
Unit protection such as bus zone, differential protection it is use.
Current transformers are used extensively for measuring current and monitoring the operation of the power grid.
Protection devices and revenue metering may use separate CTs to provide isolation between metering and protection circuits.
TRANSFORMER
A transformer is a static piece of apparatus used for transferring power from one circuit to another without change in frequency .
Physical basis of a transformer is mutual inductance between two circuit by a common magnetic circuit linked by common magnetic flux.
It can raise or lower the voltage with a corresponding decrease or increase in current.
USES OF TRANSFORMER
To transform AC to DC and DC to AC .
A major application of transformers is to voltage before transmitting electrical energy over long distance.
Transformers are usually done to change voltage either step up or step down, this works on the principle of induction.
BUSBAR
In electrical power distribution, a busbar is a thick strip of copper or aluminium that conducts electricity within a switchboard, distribution board, substation or other electrical apparatus.
Busbars are used to carry very large
currents, or to distribute current to
multiple devices within switchgear
or equipment.
USES OF BUSBAR
Bus bar are used to carry high current.
It can be used for protection of generator and transformer .
LIGHTNING ARRESTER
A lightning arrester is a device used on electrical power systems to protect the insulation on the system from the damaging effect of lightning.
A protective device for limiting surge voltages by discharging or bypassing surge current, and it also prevents the flow of follow current while remaining capable of repeating these functions
USES OF LIGHTNING ARRESTER
It protect the equipment from lightning stroke.
It is used to giving electrostatic shielding against external field.
Lightning arrester is used to provide path to unwanted excessive currents
INSULATOR
An insulator, also called a dielectric, is a material that resists the flow of electric current.
In insulating materials valence electrons are tightly-bonded to their atoms.
These materials are used in parts of electrical equipment intended to support or separate electrical conductors without passing current through themselves.
Insulator provides necessary insulation between line conductor and support.
USES OF INSULATOR
Insulators are used to hold conductors in place, separating them from one another to form a barrier between energized parts of an electric circuit and confine the flow of current to wires or other conducting paths.
An insulator can protect someone or something, from heat, electricity .
ISOLATOR
It is a disconnection switch and to be operated on no load.
Isolator is also capable of switching with the charging current and also break the bus transfer current which are its functional requirement .
An isolator switch is used to make sure that an electrical circuit can be completely de-energized for service or maintenance
USES OF ISOLATOR
It provide electrical isolation of the equipment, bus bar, and circuit from the live parts for maintenance purpose.
It is using for transfer of load from one bus to another.
MAIN FUNCTION OF SWITCHYARD.
It makes available the generated power at plant to the people.
Power generated at power station transmitted via switchyard.
Switchyard protect the plant due to sudden damage outside the plant
CONCLUSION
Switchyard is most essential part of the power
system. It is the protective part of the whole power
system. Switch yard is also most essential part for
transmission, distribution, and collection.
