SEMINAR REPORT ON220/132/33KV GRIDSUB STATIONCHANDAKA,BHUBANESWAR

1. SEMINAR REPORT ON
220/132/33KV GRID
SUB STATION
CHANDAKA,BHUBANESWAR
by
DEBASIS MOHANTY
DEPARTMENT OF ELECTRICAL ENGINEERING
VEER SURENDRA SAI UNIVERSITY OF TECHNOLOGY
SIDDHI VIHAR,BURLA—768108
[2016—2017]

2. SUB STATION
• A sub station is a place which is used to switch
generation (one voltage level to other), equipment
and circuits or lines in and out of power system
• Types of sub station
1) Indoor sub station  all equipments are
mounted inside , safer and requires lesser
area
2) Outdoor sub station all equipments are
mounted outside and requires more area

3. Main equipments at sub station
• Light arrester
• Wave trap
• Instrument transformer
1)Current transformer
2)Potential transformer
• Isolators
• Circuit brakers
• Power transformer
LET US STUDY ABOUT CHANDAKA 220KV/132KV/33KV
OUTDOOR SUB STATION IN DETAIL

4. CHANDAKACHANDAKA

9. • TWO VOLTAGE CONVERTION
STAGES
I. 220kv/132kv
II. 132kv/33kv
• INSTALLED CAPACITY (MVA) OF
TRANSFORMERS
(1) 1x160+3x100 MVA, 220/132 kV
(2) 3x40 MVA, 132/33 Kv
• Year of Commissioning 1989
• INCOMING FEEDERS(220 KV)
• Mendhasal (3 feeders)
• Bidanasi (1 feeder)

10. • Outgoing feeders
A) At 132 KV(4 FEEDERS)
i. KHURDA
ii. BIDANASI
iii. NIMAPARA
iv. RANASINGPUR
B) At 33 KV(8 FEEDERS)
i. UNIT 8 (2 feeder)
ii. NARAJ
iii. BARANGA
iv. NAYAPALI
v. XAVIERS
vi. C.S.PUR(2 FEEDERS)

11. • Advantages
• same frequency bands can be used in multiple
power system
• does not allow high frequency signal to pass
through substation bus & into transformers.
Wave trap is inserted into high voltage
transmission line to prevent undue loss
of carrier signal for all power system
conditions.
Wave trap is a parallel tuned inductor -
capacitor 'tank' circuit made to be
resonant at the desired
communication frequency . It is the
allows us to utilize the same
transmission line between 2 substation
for the purpose of communications.

12. Switching surge and lightning
Protection

13. THE COSTLIEST & IMPORTANT EQUIPMENT IN SUBSTATION
TRANSFORMER HAS TWO COILS
• PRIMARY WINDING
• SECONDARY WINDING
WORKING PRINCIPLE
• A VOLTAGE IS APPLIED ACROSS THE TERMINALS OF THE
PRIMARY WINDING
• THIS PRODUCES A FLUX THAT LINKS TO SECONDARY
WINDING
• A VOLTAGE IS INDUCED ACROSS THE SECONDARY WINDING
AND THE OUTPUT IS OBTAINED ACROSS THIS TERMINAL

14. Know Your Transformer

15. Buchholz Relay
Transformer
Oil conservator
Conservator
RELEASE COCK

16. Pressure monitoring System
Working Principle:- For the case of Serious faults inside the
transformer, oil pressure rises beyond the certain limit. Hence a
pressure relief device provided on top of the transformer opens
to allow discharge of oil and extends the tripping command. This
device automatically closes as soon as the internal pressure
falls below the critical level.

17. Temperature monitoring System
• RED POINTER READS THE
MAX TEMP ATTAINED
PREVIOUSLY
• BLACK POINTER READS
PRESENT EMBEDDED
TEMPERATURE

18. INSTRUMENT TRANSFORMERS
USED FOR CARRYING OUT MEASUREMENTS OF
VOLTAGE AND CURRENT
TYPES:
1. POTENTIAL TRANSFORMER(PT)
2. CURRENT TRANSFORMER(CT)

19. VOLTAGE TRANSFORMERS
• USED TO STEP DOWN VOLTAGE TO LOW
VOLTAGE (110 V )FOR MEASURMENT PURPOSE
AND PROTECTION PURPOSE
 It is of 2 types
Electromagnetic Voltage
Transformers
Capacitive Voltage
Transformers

20. Isolator is a manually operated mechanical switch
which separates a part of the electrical power
system normally at off load condition.
IT HELPS IN VISUALISATION OF ISOLATION OF THE CIRCUIT
Types of Electrical Isolators
1. There are different types of isolators
1. Double Break Isolator 2.Single Break Isolator
2. Depending upon the position in power system, the isolators can be
categorized as
Bus side isolator – the isolator is directly connected with main bus
Line side isolator – the isolator is situated at line side of any feeder
Transfer bus side isolator – the isolator is directly connected with
transfer bus

21. Double break isolator Single break isolator
Constructional features of double Break Isolators
Central post insulator is movable contact and two side
insulators are fixed contacts
Constructional features of single Break Isolators
Contact arm has two parts one on each post insulator
Earthing Switches
Used to remove the resudal charge and earth the isolated
conductor

22. Circuit breaker
Types of ACB
There are mainly two types of ACB are
available.
1) Plain air circuit breaker
2) Air blast Circuit Breaker.
This type of circuit breakers, is those kind of
circuit breaker which operates in air at
atmospheric pressure.
Types of circuit breaker
1. Oil circuit breaker
2. Vacuum circuit breaker
3. Air circuit breaker
4. Sf6 circuit breaker
Electrical Circuit Breaker is a switching device
which can be operated manually as well as
automatically for controlling and protection
of electrical power system respectively. It is a
on load switch.

23. oil circuit breaker
• In oil circuit breaker the fixed contact and moving contact are
immerged inside the insulating oil. due to this arc the oil is
vaporized and decomposed in mostly hydrogen gas and ultimately
creates a hydrogen bubble around the arc and decomposes it
Types of oil circuit breakers
Bulk Oil Circuit Breaker or BOCB
oil is used as arc quenching media as well as
insulating media
Minimum Oil Circuit Breaker or MOCB
These types of circuit breakers utilize oil as
the interrupting media.
interrupting unit is at live potential. The
insulating oil is available only in interrupting
chamber.
It requires less oil than oil CB
Arc quenching in bulk oil circuit breaker

24. SF6 Circuit Breaker
A circuit breaker in which the current carrying contacts operate in Sulphur
Hexafluoride or SF6 gas is known as anSF6 Circuit Breaker.
It is the mostly used cb
Advantages of sf6
SF6 has excellent insulating property.
SF6 has high electro-negativity. So absorbing free electron.
Sf6 decomposes on heating and recombines after cooling