Upload
puneet-agarwal
View
342
Download
22
Embed Size (px)
Citation preview
8/12/2019 220 KV Substation
1/24
TRAINING AT 220KVSUBSTATION JAIPUR
8/12/2019 220 KV Substation
2/24
SUBSTATION A station in the power transmission system at which elec
power is transformed to a conveniently used form.
The station may consist of transformers, switches, circbreakers and other auxiliary equipment.
Its main function is to receive energy transmitted at hvoltage from the generating station, by either step-up or st
down the voltage to a value appropriate for local use aprovide facilities for switching.
Some substation, such as power plant switchyard are simswitching stations where different connections can be ma
between various transmission lines.
8/12/2019 220 KV Substation
3/24
TYPE OF SUBSTATION
Step Up Substation
Primary Grid Substation
Secondary Grid Substation
Distribution Substation Bulk Supply Substation
8/12/2019 220 KV Substation
4/24
FEEDERS
Incoming Feeders:
Bassi(220 KV)
Heerapura(220 KV)
Outgoing Feeders:Sitapura(132 KV)
Puranaghat(132 KV)
8/12/2019 220 KV Substation
5/24
TYPICAL COMPONENTS OF APOWER PLANT SUBSTATION(SWITCHYARD)
A - Busbar
B - Disconnector
C - Circuit Breaker
D - Current Transformer
E - Voltage Transformer
F - Earthing Switch
G - Surge Arrestor
CONNECT
CONNECT & DIS-CONNECT
CONNECT, DIS-CONNECT & DETECT
DETECT & TRANSFORM
DETECT & TRANSFORM
PROTECT & SAFETY
PROTECT
8/12/2019 220 KV Substation
6/24
BUSBAR
This is a term we use for a mainbar or conductor carrying an electric
current to which many connection
may be made.
Buses are merely convenient
means of connecting switches andother equipment into various
arrangements.
Aluminum or copper conductorssupported on porcelain insulators,
carry the electric energy from point
to point.
8/12/2019 220 KV Substation
7/24
DISCONNECTS
This is an easily removed piece ofthe actual conductor of a circuit.
The purpose of disconnects is toisolate equipment.
A typical use of disconnects is toisolate a circuit breaker by installingone disconnect on either side of the
circuit breaker (in series with the
breaker).
Disconnect Switch( moving contact rod (A)
contacts with flexiblefingers (B) )
8/12/2019 220 KV Substation
8/24
CIRCUIT BREAKER
This is used to interrupt circuits whilecurrent is flowing through them.
The operation of the breaker is very rapidwhen opening.
Circuit breakers of this type are usuallyarranged for remote electrical control
from a suitably located switchboard.
Some recently developed circuit breakershave no oil, but put out the arc by a blast
of compressed air these are called air
circuit breakers.
Circuit Bre( Connected in a
phase circ
Po
Ind
8/12/2019 220 KV Substation
9/24
CURRENT TRANSFORMER
Current transformer are used withammeters, watt meters, power-factormeters, watt-hour meters, compensators,
protective and regulating relays and the
trip coil of circuit breakers.
One current transformer can be used tooperate several instruments, provided
that the combined burden does notexceed that for which the transformer is
designed and compensated.
The current transformer is connecteddirectly in series with the line.
8/12/2019 220 KV Substation
10/24
VOLTAGE TRANSFORMER
This is also know as potential transformer usedwith volt-meters, wattmeter's, watt-hour meters,power-factor meters, frequency meters,
protective and regulating relays and the no-
voltage and over-voltage trip coils of automatic
circuit breakers.
One transformer can be used for a number ofinstruments at the same time if the total current
taken by the instrument does not exceed that for
which the transformer is designed and
compensated.
The ordinary voltage transformer is connectedacross the line, and the magnetic flux in the core
depends upon the primary voltage.
8/12/2019 220 KV Substation
11/24
EARTHING SWITCH This is also known as ground disconnect, which used
connects the equipment to a grid of electrical conducto
buried in the earth on the station property.
It is intended to protect people working on the groundequipment.
It does this by completing a circuit path, thereby reducithe voltage difference between the equipment and
surroundings.
8/12/2019 220 KV Substation
12/24
SURGE ARRESTOR These are devices used to provide the
necessary path to ground for such surges, yetprevent any power current from following the
surge. An ideal arrester must therefore have the
following properties:
1. Ability to remove the surge energy from the line
in a min. time.
2. High resistive to flow of power current.
3. A valve action automatically allowing surge to
pass and then closing up so as not to permitpower current to flow to ground.
4. Always ready to perform.
5. Performance such that no system disturbances
are introduced by its operation.
6. Economically feasible
8/12/2019 220 KV Substation
13/24
OVERHEAD GROUND WIRE
This is a wire, generally of steel,supported from the top of transmission-
line towers and solidly grounded at each
tower.
It is considered a preventive device, but itdoes not entirely prevent the formation of
travelling waves on a line.
Furthermore, those lines which are notequipped with ground wires will be
subjected to disturbances which produce
surges that must be allowed to escaped
to ground
8/12/2019 220 KV Substation
14/24
RELAYS
Various types of relays used areoBuchloz Relay
oOver Current Relay
oEarth Fault Relay
o
Over Voltage RelayoDifferential Relay
oBus Bar Relay
8/12/2019 220 KV Substation
15/24
BUCHLOZ RELAY
Used for protection of oil immersedtransformers, reactors, etc.
Phenomenon of liberation of gas incase of fault generation is used to
provide protection.
Falling level of oil could be detected.
8/12/2019 220 KV Substation
16/24
OVER CURRENT RELAY
Protection from overload.
Protection devices like fuse orcircuit breaker fitted with
overload coils or series
connected trip coils are used for
over current protection.
8/12/2019 220 KV Substation
17/24
EARTH FAULT RELAY
The earth-fault relay is designed to beused for selective earth-fault protection,either primary or back-up protection, in
solidly earthed or low-resistance earthed
power systems.
When an earth-fault occurs, the relaydelivers an alarm signal, trips the circuit
breaker provide alarms, record fault data,
etc., in accordance with the application
and the configured relay functions.
8/12/2019 220 KV Substation
18/24
OVER/UNDER VOLTAGE RELAY
Relay is used for over voltageprotection and supervision in
distribution systems.
Relay is also used for over / undervoltage protection of generators,
Motors and Transformers.
They are generally used forincoming line protection.
8/12/2019 220 KV Substation
19/24
DIFFERENTIAL RELAY
Operates when the vectordifference of two or more
quantities exceeds a
predetermined value.
The relay has ratio matchingtaps and incorporates a secondharmonic restraint function
where large transformer
magnetizing in rush is present.
8/12/2019 220 KV Substation
20/24
BUS BAR RELAY
The scheme of busbar protection, statesthat total electric current entering anelectrical node is exactly equal to total
current leaving the node.
But this scheme has also a maindisadvantage. This scheme of protection
can not discriminate the faulty section of thebusbar.
Very short tripping time (
8/12/2019 220 KV Substation
21/24
OTHER DEPT. OF SUBSTATION
CONTROL ROOM
POWER LINE CARRIER COMMUNICATION ROOM
BATTERY ROOM
8/12/2019 220 KV Substation
22/24
CONTROL ROOM
Contain meters, control switches andrecorders located in the control building
Used to control the substationequipment to send power from one
circuit to another or to open or to shut
down circuits when needed.
Annunciator is present which consist ofsounding alarm and an indicator which
indicate nature of fault and zone where
fault occurred.
8/12/2019 220 KV Substation
23/24
POWER LINE CARRIER COMMUNICATIOROOM
Used in case of largeinterconnected system where
control leads dispatch station
has to co-ordinate the working of
various unit to see that thesystem is maintained
most economic and reliablemethod of communication in
power network
8/12/2019 220 KV Substation
24/24
BATTERY ROOM
Batteries used are lead acid typehaving solution of sulfuric and
distilled.
Room is kept maintainable so it isnota ccumulated with acid vapours
to avoid risk of explosion.
Batteries are kept at healthy stateat 2.1/2.2 V/cell.