2. 2014-2015
(10 June 2014 to 10 July 2014)
SUBMITTED BY:
SRIJAN TRIPATHI
11EAYEE049
B. Tech. IV Yr., VII Sem.
3. CONTENT
Substation
Main equipment at substation
Transformer
Lightning Arrestors
Current Voltage Transformer
Wavetrap
CT & PT
Isolator
Circuit Breaker
Bus Bar
4. Substation
An Electrical Substation is a subsidiary station of an
electricity Generation , Transmission And
Distribution System where voltage is transformed
high to low or reverse using transformer.
Examples of Substation:-
400kV/220kV substation
220kV/132kV substation
132kV/33kV substation
33kV/11kV substation
33kV/.4kV substation
5. ABOUT 220KV SUBSTATION CANTT
INCOMING LINES
220 KV REWAROAD LINE
220 KV FATEHPURLINE
OUTGOING LINES
132 KV REWAROAD LINE
132 KV MANURI LINE
6. 220kV Substation
It is devided into two(2) parts:-
A. Panel Section
A. Control Panel Section
B. Relay and Protection Panel Section
B. Switch Yard
A. 220kV Section
B. 132kV section
C. 33kV section
C. Battery Room (Extra)
7. TRANSFORMERS
Also known as the heart of
substations. These are
used to reduce the voltages
at appropriate levels
CURRENT VOLTAGE
TRANSFORMERS
It is a used in power
systems to step downextra
high voltage signals and
provide a low voltage signal,
for measurement or to
operate a protective relay
WAVETRAP
Traps the high frequency
signals
ISOLATORS
Used for maintenance of the
circuit in no load condition
CIRCUITBREAKER
used to protect the
eqiupment by opening the
circuit for over current and
over voltages
LIGHTINING ARRESTER
Used for protecting the
equipment from surge
voltages
MAIN EQUIPMENTS AT ALLAHABADCANTT
SUBSTATION 220KV
8. TRANSFORMERSTRANSFORMERS
POWER TRANSFORMERS
Transformer is a static machine, which transforms
the potential of alternating current at same
frequency. It means the transformer transforms the
low voltage into high voltage & high voltage to low
voltage at same frequency. It works on the principle
of mutual inductance.
When the energy is transformed to a higher voltage,
the transformer is called step up transformer and
then it is transmitted at lower voltage it is called
step down transformer.
There are 3 transformers in the substation:
160MVA, 220/132 KV (2nos.)
100 MVA TRANSFORMER(1)
9. PowerTransformerfeedingPowerTransformerfeeding
160 MVA transformers are manufactured by
ADITYA and by TRM. These are the power
transformers and , there efficiency is high.
Primary side is star connected while secondary is
delta connected.
There are seventeen tapping in it.
Every transformer has OLTC to change the tap
for controlling voltage.
TYPES OF COOLING:
AIR NATURAL COOLING
AIR BLAST COOLING
OIL NATURAL COOLING
OIL BLAST COOLING etc.
10. LIGHTNING ARRESTER
DEFINATION
A lightning arrester is a device used on
electrical power systems to protect the
insulation on the system from the
damaging effect of lightning.
11. L.A CIRCUIT DIAGRAM
1.Rod arrester
2.Horn gap arrester
3.Multi gap arrester
4.Expulsion type lightning arrester
5.Valve type lightning arrester
6. Silicon Carbide Arrestors
7. Metal Oxide Arrestors
At MURAD NAGAR substation we use
ZINC OXIDE ARRESTOR GAPLESS
ALSO KNOWN AS SURGE ARRESTER
USED IN THE POWER SYSTEMS TO
PROTECT FROM LIGHTNING
WHEN SUURGE TRAVELS ALONG
THE LINE , THE ARRESTOR DIVERTS IT
TO THE EARTH
12. CAPACITOR VOLTAGE TRANSFORMER
A capacitor voltage transformer (CVT),
or capacitance coupled voltage
transformer (CCVT) is a transformer used
in power systems to step down extra high
voltage signals and provide a low
voltage signal, for measurement or to
operate a protective relay.
In its most basic form the device consists
of three parts: two capacitors across which
the transmission line signal is split,
an inductive element to tune the device to
the line frequency, and a transformer to
isolate and further step down the voltage
for the instrumentation or protective relay.
14. WAVE TRAPWAVE TRAP
Reliable & fast communication is
necessary for safe efficient &
economical power supply . To
reduce the power failure in extent &
time, to maintain the interconnected
grid system in optimum working
condition to coordinate the
operation of various generating unit
communication network is
indispensable for state electricity
board.
15. Current transformer
Reduced high voltage in a
fixed voltage and
measurements purpose
also
Potential transformer
Measurement of electric
currents and protective relays
17. STEPS OF OPERATION OF ISOLATORSTEPS OF OPERATION OF ISOLATOR
SEQUENCE OF STEPS FOR ATTENDING
MAINTENANCE:
1.Open CB on no load or full load
2.Open the isolator on no load
3.Close the earth switch
SEQUENCE OF STEPS FOR KEPT IN
SERVICE
1.Open the earth switch
2.Close the isolator
3.Close the CB
18. CIRCUIT BREAKERCIRCUIT BREAKER
A circuit breaker is equipment, which can
open or close a circuit under normal as well as
fault condition. These circuit breaker breaks
for a fault which can damage other instrument
in the station. It is so designed that it can be
operated manually (or by remote control)
under normal conditions and automatically
under fault condition. Whenever a fault
occurs trip coil gets energized, the moving
contacts are pulled by some mechanism &
therefore the circuit is opened or circuit
breaks.
19. Sulpar hexafluoride
circuit breaker (SF6)
Sulphar hexa fluoride (SF6)
gas is used as the arc
quenching medium . The SF6
is an electronegative gas and
has a strong tendency to
absorb free electrons. Circuit
breakers have been developed
for voltage 115KV to
230KV , power rating10
MVA
Vacuum circuit breakers
Vacuum circuit breakers are
circuit breakers which are
used to protect medium and
high voltage circuits from
dangerous electrical
situations
Air-blast circuit breaker
Fast operations ,suitability for repeated
operation , auto reclosure , unit type
multi break constructions ,simple
assembly , modest maintenance are
some of the main features of air blast
circuit breakers. A compressors plant
necessary to maintain high air pressure in
the air receiver.
Oil circuit breaker
A high-voltage circuit
breaker in which the
arc is drawn in oil to
dissipate the heat and
extinguish the arc; the
intense heat of the arc
decomposes the oil .
DIFFERENT CIRCUIT BREAKERS
21. Bus-bars
Bus Bars are the common electrical component through
which a large no of feeders operating at same voltage
have to be connected.
Carry electrical supply