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1. Operated by : Power Grid Corporation Of India limited
A Government Of India Enterprise
Government Engineering College Bikaner
Summer Internship : By Saumya Tomar & Kusum Sihag
Under the guidance of :
Mr . Shyam Sundar Prajapat
Mr . Kuldeep Rawat
Mr . Uday Garg
Training end Date: 27/07/2023
Submitted to : Dr . Manoj chimpa

2. Overview to Power Grid
•Power Grid Corporation of India Ltd. Is a “Maharatna” public sector
enterprise of government of India. It was incorporated on 23rd Oct.
1989 under the company act ,1956. It is India`s largest transmission
utility.
My training is done from the Powergrid Bikaner Substation(Jalalsar).
The station has power transmission rating
as(765KV/400KV/220KV).There are 8 lines are as follow :
•765KV connecting following substations.
•1. Bhadla [I] – Bikaner
•2. Bikaner – Moga
•3. Bikaner – Bhadla [II]
•4. Bikaner – Khetri
•The Khetri substation is nowcontrolled by AdaniGroup .
•400KV Connecting following substation

3. BASIC INFORMATION
In order to understand the circuit designing and power connecting lines one should have
basic knowledge of electrical
and electronic engineering and basic electrical components.
Some of which are describe below:
1. GRID-A Network of synchronized power provider and consumer that are connected by
transmission and
distribution lines and operate by one or more control centre.
2. POWER-Electrical power is the rate at which electrical energy is converted to another
form, such as motion, heat or
an electromagnetic field.
3. INTERCONNECTED-The interconnected is a transmission system and any other
connected system elements that are
likely to have an impact on the electricity supply at a national level(including power
station with a capacity of more than
500KVA).

4. 4. CURRENT-An electric current is a flow of electrical charge carriers ,usually electrons or
electron –atoms .the standard unit is the ampere ,symbol A.
5. VOLTAGE -Voltage is the rate at which energy, electricity or electromagnetic forces are
drawn from a source. The standard unit is volt, symbol V.
6. OHM’S LOW -A law in electricity the strength of a direct current is directly
proportional to the voltage and inversely proportional to the resistance of the circuit.
FORMULA: V=IR
7. INDUCTOR -An inductor is a passive electronic component that stores energy in the
form of a magnetic field. An inductor consists of a wire loop or coil. The inductance is
directly proportional to the no. of turns in the coil.
Condition –opposes sudden change in current.
V= L di \dt
Energy storing element -E = 1/2 LI^2

5. 8. CAPACITOR -The Capacitor is a component which has the ability or “capacity” to
store energy in the form of an
electrical charge producing a potential difference (static voltage) across its plates.
C=Q/V
Condition-opposes sudden change in voltage.
Energy storing element –E= 1/2 CV^2
9. OPEN CIRCUIT -An electrical circuit in which the continuity is broken so that current
does not flow
10. SHORT CIRCUIT -A short circuit is an electrical circuit that allow a current to travel
along an unintended path with no or very low electrical impedance.
11. PHASE -A phase is the current, or the voltage among an
existing wire as well as a neutral cable.

6. •SCADA SYSTEM
Supervisory control and data acquisition [SCADA] the line
connection and the circuit design are too complex and difficult to
control their switching. So scadasystem helps one to understand
the circuitry design of any station. By the help of scadasystem
one can easily control the switching condition of wherever
required. This system is so advanced that if a person a sitting in
any other substation can easily can take access over any required
substations lines and their components

7. 400 KV 765 KV

8. 220 KV Scada System

9. About PGCIL
THE PGCIL BIKANER,
SUBSTATION PGCIL Bikaner
substation is located in village
jamsarwhich is 32 km far away
from main Bikaner city.
Jamsaris nearest to jalasaris 2km
away from substation.
Total Area of PGCIL , JALASAR is
900*500m.
It mainly evacutespower from near
by solar power station and supply it
KHETRI, AJMER, MOGA and BADLA.

10. Main Equipment Of Power Grid Substation
1 . EARTHINGWIRE:
It is used for protection purpose
and allows a path foraccessamount
of current in the circuit to the earth.
Asearthis super conductor all
excess charge will attractedtowards
the ground.
Overhead power lines are often
equipment with a groundconductor
(shield wire or overhead earth
wire). A ground conductor is a
conductor that is usually grounded
(earthed) at the top of the
supporting structure to minimize
the likelihood of direct lighting
strikes to the phase conductors.

11. LIGHTINGARRESTER
This instrument which is used for the
protection of the equipment at the
substation against
travelling waves, such type of devices is
called lightning
arrestor. It is connected between the line
and earth. i.e., in parallel with the
equipment to be protected at the
substation.
Lighting zinc oxide structure only shunt
(parallel) conductor or ground.
This instrument used in PGCIL JALASAR
BIKANERMODEL NO. = SC07-1
COMPANY NAME= = CG power and
industrial solution limited ,
lighting arrester division ambad, nashik.
Rating in unit =AC ma

12. CAPACITY VOLTAGE
TRANFORMER
Capacitive voltage
transformers are used to
convert high transmission line
voltage (up to 1200kV) to
standardized low and easily
measurable values, which will
be used for metering,
protection and control of the
high voltage system.
CVT devices are less expensive
than that potential
transformers.

13. Wave Trap
Wave trap is a device which prevents the
high –frequency carrier signals to enter
the substation side. It is also known as
wave trap. It is connected in series with
thetransmissionlines. It is designed to
carry the rated power frequency (50hz or
60hz) current ,as well as to withstand the
substation fault currents.
It is an inductor having tuned LC circuit,
which is mainly
used for PLCC purpose. It offers very high
impedance to
high frequency PLCC signals does not
allow them to enter
in S/Y and offers very low impedance for
frequency
currents.

14. Isolator
An isolator switch is used to make sure that an electrical
circuit is completely de-energized for service or
maintenance. Such switches are often found in electrical
distribution and industrial applications where machinery
must have its source of driving power removed for
adjustment or repair. High-voltage isolation switches are
used in electrical substations to allow isolation of
apparatus such as circuit breakers and transformers, and
transmission lines, for maintenance.
An isolator can open or close the circuit when either a
negligible current has to be broken or made or when no
significant voltage change across the terminals of each
pole of isolator occurs. It can carry current under normal
conditions and can carry short circuit current for a
specified time. They can transfer load from one bus to
another and also isolate equipment’s for maintenance.
Isolators guarantee safety for the people working on the
high voltage network, providing visible and reliable air gap
isolation of line sections and equipment. They are basically
motorized i.e. motor does the closing and opening of the
isolator.
Isolators are distinguished as "off load" and "on load"
isolator.

15. RELAYA
Relay is an electrically operated switch. Many relays use
an electromagnet to operate a switching mechanism
mechanically, but other operating principles are also used.
Relays are used where it is necessary to control a circuit by
a low-power signal (with complete electrical isolation
between control and controlled circuits), or where several
circuits must be controlled by one signal. Relays with
calibrated operating characteristics and sometimes
multiple operating coils are used to protect electrical
circuits from overload or faults; in modern electric power
systems these functions are performed by digital
instruments still called "protective relays".
TYPESOFRELAYS-
1.Electromagnetic attraction relay
2. Electromagnetic induction relay
3. Thermal relay
4. Numerical relay
5. Over current relay

16. 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
inmdediatelydiscontinue electrical flow. Unlike a fuse, which
operates once and then has to be replaced, a circuit breaker
can be reset (either manually or automatically) to resume
normal operation. Circuit breakers are made in varying sizes,
from small devices that protect an individual household
appliance up to large switchgear designed to protect high
voltage circuits feeding an entire city.
The type of the circuit breaker is usually used for substation.

17. SF6–
Sulphur hexafluoride or SF6 circuit breaker is a type of ciruitbreaker that uses pressurized SF6 gas to extinguish the
arc. It is a high dielectric strength gas having superior insulting and arc properties far better than air or oil it is used for
arc in high voltage circuit brakers up to 800 kvin power stations, electrical grids etc.
SF6 gas has a strong tendency to absorb free electrons.
SF6 is stable, inert, non-toxic, non flammable gas. It has dielectric strength 2.35 times that of air at atmospheric
pressure.

18. PROTECTIONFOREQUIPMENT
The current and voltage value of the substation are very veryhigh the value of voltage is so high that the air
surrounding the these line also gate charge due to by induction so protection of equipment become very
important and serious issue for planning the substation tower carrying 765/400/220 KV lines are kept at sufficient
height at ground.
Many equipment togetherlycontribute for overall circuitry
design such as LA , earth wire , switch , rellay, and other
many important instruments as mention above.

19. Reactor

20. REACTOR
Reactor is used for absorbing the reactive power from the electric power transmission system. When the high
voltage in transmission line. Mainly reactor is used as a shunt reactor inside the power grid system.
Shunt reactor are used to control voltage and compensate reactive power. Shunt reactor provide voltage control
and reactive power compensate.
They are arrange between line voltage and ground.
A three phase shunt reactor is generally connected to 400KV or above electrical bus bar system for capacitive
reactive power compensation of the power
system,Andto control dynamic over voltage occurring in the
system due to load rejection.
The shunt reactor should be of gapped core type or magnetically shielded air core type.
The impedance should be maintained at a constant value for avoiding harmonic current generated due to the
system over voltage.
Shunt reactor are only one winding per phase.
Those three winding are star connected with the neural point accessible . the neutral point is connected to the
earthing system of the installation through the tertiary
winding of a directly.
Shunt reactors may be oil-immersed with conservator or dry type.

21. Transformer
Transformer is the equipment that change the voltage of electricity-either
up or down –as part of the power grid.
Transformer are often located in substation, where they help transform the
electricity supplied by power plants into a voltage suitable for consumers.
There are two type of transformer-
1. Power transformer
2. Current transformer
1.Powertransformer
A power transformer is used in the national power grid, where
Electricity is converted from alternating current (AC) to direct
current (dc). The purpose of a power transformer is to convert
voltage from a high voltage to a low voltage.
A single phaetransformer is basically made out of two
separate windings that are instertedinto each other.
The active part of a transformer is made of the elements that
are in contract that are contract with the voltage and current,
and are mainly composed of –
WINDING
CORE
BUSHING
RADIATOR
OIL LEVEL TEMPERATURE METER
SILICA GEL

22. Silica Gel
The silica gel is a very good absorber of
moisture. Silcagel is an adsorbent that help
in adsorbing the moisture,humidity,odor
etc.
The main function of silica gel is to control
the amount of moisture available within a
breather transformer.
Breathing is a phenomenon in transformer
breathe in or breathe out the air. Silica gel
blue is available in beads or granlus
formandis of light pink color when fully
absorb moisture while as silica gel orange
beads are also use for effective moisture
dying in breather transformer.therehave a
small amount oil under silica gel which suck
the moisture of air and further sendthisair
to silica gel which further suck the rest of
the moistureofthe air.

23. Current Transformer
Current transformer (CT) is used to measure the
current of another circuit. Ctsare used worldwide
to monitor high voltage lines across national power
grids. A CT is designed to produce an AC in its
secondary winding that is proportional to the
current that it is measuring in its primary.
Than the accuracy are 0.5 of current transformer.
The 400 / 200 k v current transformer has five core
which is
used for following CORE 1 -BUS BAR 1 PROTECTION
CORE 2 –BUS BAR 2 PROTECTION
CORE 3 –METERING
CORE 4 -MAIN 1 PROTECTION
CORE 5 –MAIN 2 PROTECTION

24. BUSBAR
The electrical function used for the electric
power from the incoming feeder and
distributes then to the out going feeders.
The main purpose of a bus bar to carry
electricity and distributed . Busbar are used
to make the system more efficient.

25. Corona Effect
The phenomena of ionisation of surrounding air around a conductor
due to which luminous glow with hissing noise is rise is known as
corona effect.
Air acts as dielectric medium between the transmission lines. In other
words it acts as an insulator between two conductors.

26. Thankyou