a report submitted by Kishan Gabel for the Industrial training persued at JSPL in the field of Electrical Engineering.

1. 25
REPORT: A vocational training at:
JSPL
Jindal Steel and Power limited
A world class company.
Kharsia road, Raigarh,
Chhattisgarh 496001
2015
Submitted By: Kishan Gabel
National Institute of Technology,Raipur

3. Acknowledgement:
I am grateful to Jindal Steel and Power Limited
to give me such an opportunity to visit inside
the plant and earning practical knowledge
about the Electrical system and process.
I am very much thankful to the respected
sir, Mr. Rajesh Agrawal (Head of the
department, EPS), Mr. M.V. Sudhakar sir
(Manager, MRSS-2), Mr. Karamchand
Dewangan sir and all the concerned officers to
allow for the visit & guide me to make this
visiting valuable.
Kishan Gabel
B.Tech. 2nd year
Electrical, NIT Raipur

4. Jindal Steel and Power Limited (JSPL)
is an Indian steel and energy company based in New-Delhi with
turnover of approx. US$ 3.3 billion. JSPL is a leading player in
steel, power, mining, oil and gas and infrastructure in India. The
company produces steel and power through backward integration
from its own captive coal and iron-ore mines.
JSPL has 6 major subsidiaries:
 Jindal Power Limited which operates JINDAL TAMNAR
POWER PLANT a 1000 MW (4x250 MW) coal-based thermal
power plant in Raigarh in state of Chhattisgarh. This plant is
fully functional.
 Jindal Shadeed Iron and Steel, Oman
 Jindal Steel Bolivia
 Jindal Steel and Power Mauritius
 Jindal Africa Investments
 Skyhigh Overseas

5. #LAYOUT AND CONNECTION DIAGRAM OF ELECTRICAL
POWER SYSTEM FOR ALL INTERCONNECTED JINDAL
PLANTS:
About Main Receiving Substation (MRSS):
JPL
4X250 MW
DCPP
4X135 MW
CSEB
MRSS-3 MRSS-1
MRSS-4
MRSS-2NSPL

6. This is mainly a system arranged at generating or distributing
areas to control and protect the electric power being
transmitted through transmission lines. In other words, this
helps to maintainthe balancedpower flow and outgoing to any
feeder.
These substationsare arranged also to protect the equipments
installedat the line or to provide isolationto a specific line in
faulty conditions,such as short circuit or ground faults.
#Components of a substation:
 Incoming line
 Main bus
 Isolator
 Potential transformer
 Current transformer
 Circuit breaker
 Bushings
 Insulators
 Power Transformer
 Outgoing feeders
 Conductor & cables
 Gantry structures
 Incoming lines (or incomers)

7. These are mainly transmission lines which are used to charge the
main bus situated at any substation;or it may be any cables or
conductors. All the bays or divided supplies are charged by
connecting it to the main bus which is charged by the incomer.
 Main bus
Bus in a substation works like a main charging spot for all the
feeders and outgoing bays, the outgoings in turn charges
another bus of any other substations.

8.  Isolator
There are two types of isolators:
1.Bus isolator
2.Line isolator
 Bus isolator isolates the line to main bus.
In case of more than one buses are there then bus
isolator helps us to choose from which we want the line
to be charged.
 Line isolator isolates the buses from the main
lines of transmission. This completely removes the
connection of any bus to be charged.

9.  Potential transformer (voltage
transformer, VT)
This is a type of measuring instrument which
uses the principle of operation of transformer to
measure the
potential of any
line in terms of
phase to ground
voltage.
Connection
diagram:

10.  Current transformer (CT)
This is also a type of measuring instrument in which
high current is measured in terms of low value. This
is made of a step-up transformer followed by a low
range ammeter.

11.  Circuit breaker (CB)
There are three categories for circuit breakers:
1.Low current
breaker
2.Medium current
breaker
3.High current
breaker

12. Also there are many types of circuit breakers:
1. Miniature circuit breaker(MCB)
2. Moulded case circuit breaker(MCCB)
3. Vacuum circuit breaker(VCB)
4. Air circuit breaker(ACB)
5. SF6 circuit breaker
6. CO2 circuit breaker
Circuit breakers work as a switch to open or
close the line in which this is installed. Thus it
provides protection in case of any fault in the line by
simply opening the connection, which is called
“Tripping”.
While isolator does the same work as circuit
breaker but the main difference is the mode of
operation of the two equipments. Circuit breakers
are specific to operate at loaded condition while
isolator can’t be used on loading, it can only be used
in off-load or open circuited condition.
 Bushings
Bushings are nothing but the insulation provided
between the body and any of the equipment. These
are made up of Porcelain. In transformers two types
of bushings are provided; namely HV bushings and

13. LV bushing. HV bushings are provided to connect
the internal windings of the transformer to the
outer conductor without having body contact to the
transformer.
 Insulators
Insulators are the non conducting medium made of
insulating material. The resistance offered by this
material is very much higher than the conductors;
therefore this is used to restrict the current to the
conductors itself. Work of insulators is to
mechanically support the conductors with the
gantries.

14.  Power transformer
Transformers which are used to transfer power at
one voltage level to another voltage level
throughout same frequency.
Power transformer 100/120 MVA on 220kV yard

15. Nameplate rating for 100/120MVA power
transformer:
Cooling type: oil natural

16.  Outgoing feeder:
The output to a substation is called a feeder. Feeder means the
component which feeds power to a specific system, it maybe a
furnace or a motor driving system.
 Conductors and cables:
Mainlytwo types of current carriers are used in substations.
One is the bare conductorwhile the other is through power
cable. Bare conductorsare used where more height can be
given to the conductor
and no need to
insulate the current
carrier while cables
are used for relatively
low voltage power
transmission and
wherever transmission
medium is
underground or under watered. Power cables provide
insulationas well as protection to the conductorwhereas bare
incomer lines
power transformers
Feeders

17. conductors don’t have the same.
 Types of Conductors:
1.ACSR (Aluminium conductor steel
reinforced)
These are manly used
for long transmissionlines
because the steel used
provides more strength to the Aluminium which is the
main media for current to flow through.
2.AAAC (All Aluminium alloy conductor)
These conductors are
nothing but strands of
Aluminium alloy, which are
arranged layer wise. These
have lower mechanical strength than ACSR conductors

18. but current
conducting media
has higher area of
cross section.
Therefore this
provides relatively
low resistance than
ACSR conductors at the cost of mechanical strength.
3.AAC (Aluminium alloy conductor)
It constitutes in parts; one part contains the alloys of
Aluminium while another part contains Aluminium in
metal form. These are not generally used now-a-days in
substations. Basically these conductors are for lower
strength transmissionand distribution.
 Gantry structure:
The metallicsupporting structures which are used to
support the conductors
and to provide base for
installation ofvarious
types of equipmentslike
CT, PT and LA, are called
gantry. Generally gantries
are made up of steel and
are pre-fabricated by its
provider company. All the gantries used inside any of the
substationsare also provided with alternative earthings.

19.  About ETL(electro technical lab)
All the equipments
must be treated so
healthily as to
maintain proper
working and lossless
operation. In order to maintain these operations
regular and standardised testing is required. In ETL
lab, testing of various components of transformers,
breakers and other equipments is done under
expertise surveillance. On field as well as sample
testing is done in this laboratory. Some of the tests
are named as given below:

20.  AC testing:
 Magnetic balance test
The core of the transformer is tested for the
distribution of the flux to be uniform throughout the
core for all the primary and secondary windings.
 Magnetising current test
After applying the AC voltage at no load, the primary
and secondary of the transformer must have the at
most current value. The core magnetising current is
generally 2-3% of the rated current.
 Turns ratio test
transformer
testing
AC
magnetic
balance
magnetizing
current
turns
ratio
DC
winding
resistance
polarisation
index
insulation
resistance

21. AC voltage of any definite magnitude is applied to
any of the primary or secondary of the transformer
then the induced open circuit voltage of the other
winding is tested whether it is according to the ratio
of the nameplate ratings of the transformer or not.
For a 220kV/33kV transformer this ratio is found to
be 6.667.
 DC testing:
 Winding resistance test
The transformers windings are tested whether the
resistance is in the proper limit to a specific value or
not. Main purpose of this testing is to minimize &
maintain the Copper losses occurring inside the
transformer. The readings of the windings resistance
is found of the order of milli-ohms (mΩ).
 Insulation resistance test

22. The windings are tested for the following faults
which may occur: phase-to-phase short circuit,
phase-to-ground short circuit and any other
insulation failure inside the transformer body is
maintained under this. The insulation resistance is
measured with Megger up to one minute.
 Polarisation index test
Both Insulation Resistance Test (IR) and Polarisation
Index Test (PI) are conducted on HV machine to
determine service condition of the insulation. In HV
machines windings are likely to be affected by
moisture and contamination. IP test is conducted
specially to determine the dryness and cleanliness of
the winding insulation.
 TRW (Transformer Repair Workshop)
In this workshop various components of the substation are
repaired under the guidance of experts. Various transformers
like power transformers, current transformer, potential

23. transformers etc. are repaired and their proper operation is
maintained.
Transformer oil tankers
 Rectifier & Battery bank arrangement
 DC power supply is must to run some basic control
equipments inside as well as outside any power system.
Therefore, an alternate source of DC should be arranged.
 When AC power is available to us, we can get desired
amount of DC supply by rectifying the AC power through step
down transformers and thyristors.
 In case of AC failure, we use battery banks to provide
uninterrupted power supply.
 Battery-banks

24.  A battery bank is
nothing but the series
connection of multiple
similar type batteries.
 The numbers of
batteries are considered
according to the ratings
of a single cell as well
as the desired DC voltage level.
 Control Room
The main control and monitoring is done at indoor arrangement.
Basically this room has
panels installed inside the
room itself. The panels
have their input and
output communications
through incomers and
command lines which are connected to the main bus of the
control panel.
Control panels are available at indoor of any substation for
each individual voltage bus, means separately for 220kV and
33kV also ACDB and DCDB.
 Cooling towers

25. Cooling towers are installed at the substation to exchange heat
through heat exchanger for SVC yard. Pumping by Induction
motors are done in order to maintain regular cycling of water
and the heat exchanger.
(Schematic diagram for cooling tower)
 SAFETY:
 Must wear helmets to protect your head from any fallen
object or to pass through any low clearance door.
 You should wear good standardised safety shoes in order
to protect your legs from any hard injury.
 Wear glasses to protect your eyes.
 Avoid loose cloths.

26.  Don’t make large steps while walking through yard.

27. THANK YOU FOR
READING AND
COOPERATION.