2. PRESENTATION ON VOCATIONAL TRAINING
TRANING PLACE :- C.S.P.D.C.L.AMBIKAPUR
TRAINING STARTING ON 07.05.2013 TO 06.06.2013
 SUPERVISION BY:-
 MR.D.K.SHARMA
A.E.IN CSPDCL(O&M)
(AMBIKAPUR TOWN)
 SUBMITTED TO :-
 MR.P.R.MISHRA
H.O.D. E.E.
VEC LAKHANPUR

3.  INTRODUCTION
 SCHEMATIC POWER SYSTEM DAIGRAM
 CLASSIFICATION OF SUBSTATION
 MAIN EQUIPMENTS OF SUBSTATION
 TYPE OF INSTRUMENT TRANSFORMER
 TYPES OF CIRCUIT BREAKERS
 EARTHING SWITCH
 LIGHTING ARRESTOR
 BUS BAR
 FUSE
 INTRODUCTION OF PROTECTION SCHEME
 PF IMPROVEMENT
 MINIMUM CLEARANCE
 CONCLUSION

4.  Chhattisgarh State Electricity Board was Formed in Accordance
with the section 5 of the Electricity Supply Act 1948 as Per the
Notification Published in the gazette of the Government of
Chhattisgarh Dated 15th November 2000. Chhattisgarh State
Electricity Board (CSEB)became functional w.e.f. 01.12.2000.
 Chhattisgarh State Electricity Board has been reorganized into
following Five Companies in accordance with the provisions
contained in the section 131-134 of Electricity Act 2003 by the
Government of Chhattisgarh vide notification dated 19.12.2008

5. 33 KV
Bus P.T
11 KV
33/11 KV sub
station
LA
ES
ISO
CT
CB
CB
LA
LA
T/F
CB
CT
CT CT
CT

6. According to Design.
1.Indoor type
Sub-station.
2.Out door type
Sub-station.
(a) Pole mounted
Sub-station.
(b) Foundation mounted
Sub-station.

7.  1) Power transformer
 2) Circuit breaker
 3) Isolator
 4) Earthing switch
 5) lightning arrestor
 6) BusBar
 7) Current transformer
 8) Potential transformer
 9) Protective relay
 10) DC battery set
 11)Capacitor bank
 12)Fire fighting system

8.  Transformer is used to step down the voltage from 33 kv voltage
to 11kv voltage .
 Generally 3.15 MVA, 5 MVA, 10 MVA 33/11kv, Δ / Y transformer
are used in 33/11kv .

11.  Check Oil level in main tank & OLTC tank.
 Check the color of silica gel in breather ;it must
be blue in color .if it is turned pink then
recondition it or replace it.
 Check On load Tap Changer Lower/Raise trail
by Local & Remote.
 Trip trail by draining oil in Buchholz relay

12.  Check Earth resistance ,provide watering
arrangement for earthling pits.
 Tight all connections.
 Check breakdown voltage of oil.
 Clean the bushings.
 Attend the oil leakages
 Note Temperature of Oil & leakage.

13.  Check cooling system & confirm fan control
operation w.r.to temperature variation.

14.  33/11 KV, Δ / Y , 3.15 MVA, 5 MVA, 10 MVA

15. CURRENT
TRANSFORMER
POTENTIAL
TRANSFORMER

16.  Current T/F is used for protection and
metering purposes.
 It steps down the current level of the line for
following purposes.
1) Measurement :- ammeter , kw meter , kwh
meter , power factor meter
2) control and protection :- current when exceeds
the set value operates the relay which senses
the faulty condition .

18.  300 -150 / 5 A
 200-100 / 5 A
 100-50 / 5 A
 50-25 / 5 A

19. It steps down the voltage level of line for -
1) Measurement : voltmeter, frequency meter ,kw
meter, kwh meter ,power factor meter
2) Control & protection : used in directional over
current protection and under frequency relay
operation (48.8 Hz , df/dt relay)

21.  For 33 KV :- 33 KV / 110 V/√3
 For 11 KV :- 11 KV / 110 V/√3

22.  Circuit Breaker can switch automatically
during normal and abnormal conditions .
during faulty condition the fault is sensed by
the relay and operates the circuit breaker to
isolate the fault.
In 33kv substation generally vacuum circuit
breaker are used where are quenching medium
is vacuum

23.  Low voltage air circuit breaker.
 Oil circuit breaker.
 Air blast circuit breaker.
 SF6 circuit breaker.
 Vacuum circuit breaker.

24. 11 KV 33 KV
Rated
Voltage
12 KV 36 KV
Normal
Current
400 A 630 A
S.C Breaking
Current
8 & 12.5 KA 12.5 KA (750
MVA)
DC Voltage 24 V 24 V

25.  High resistance interruption.
(1) Arc lengthening.
(2) Arc cooling.
(3) Arc splitting.
(4) Arc constraining.
 Low resistance interruption.
(1) Cooling.
(2) Gap lengthening.
(3) Blast effect.

26.  1) no oil is required for are quenching
 2) least maintenance
 3) compact size
 4) light in weight
Maintenance of circuit breaker
 1) close/trip through local/remote control
 2) trip trial through auto closer relay
 4) oiling & greasing of moving parts
 5) vermin proofing
 6) heater healthy

27.  Isolator is used to isolate the equipment.
 Isolator is operate at no load.
Maintenance of isolator:-
1) Oiling &greasing of moving parts.
2) check contact firmness .
3) check open / close trials.
4) Earthing switch .

28.  It is operated on No Load Only.
 Rated Voltage :- 12 KV
 Normal Current :- 400 A

29.  Rated Voltage :- 36 V
 Normal Current :- 630 A

30.  Earthing switch discharges the voltage an
deadline to earth . it is connected between line
unit of isolator to earth .
NOTE:- it there is breakdown at line then for
measurement of resistance by megger do not
close earth switch .

32. 11 KV 33 KV
Voltage Rating 9 KV 30 KV
Normal
Discharge
Current
5 KA 10 KA

33.  Busbar are conducting rod to which a number
incoming and outgoing feeders are connected
in 33kv S/S there are 33kv bus & 11kv bus .
VARIOUS TYPES OF BUS BAR
ARRANGE- MENT SYSTEM:-
 Single bus bar system used in D.C. and A.C.
power station.
 Single bus bar system with sectionalization .
 Ring bus bar system.
 Duplicate bus bar system.

36. Copper.
Tin
Lead.
Silver.
TYPES OF MATERIAL USED IN FUSE WIRE:-

37.  Rewireable fuse.
 Cartridge type fuse.
 Drop out fuse.
 High capacity H.R.C. fuse.
 High voltage H.R.C. fuse.
Types of Fuse element

38.  Rewireable fuse.
 Cartridge type fuse.
 Drop out fuse.
 High capacity H.R.C. fuse.
 High voltage H.R.C. fuse.
TYPES OF FUSES:-

39.  11 KV , 50 HZ.
 Rated Voltage :- 12 KV
 Rated Normal Current:- 100 A.

41.  DESIRED CHARECTERISTICS OF PROTECTION SYSTEM:-
Characteristics of protection system.
1.Reliability
2.Sensitivity.
3.Selectivity.
4.Descrimination.
5.Speed.
6.Simplicity.
7.Economy.

42. FUNCTION OF PROTECTIVE RELAYS:-
 The relay is used to cut off the power supply,
promptly to any element of power system which
undergoes short –circuit it starts operating
abnormally.

43. Main features of a good protective relay.
1.Reliability
2.Sensitivity.
3.Selectivity.
4.Quickness.
5.Non interference
With future extension.

44. 1) Differential Relay
2) Over Current Earth Fault Relay
3) Buchholz Relay

45.  This is the main protection provided to the transformer. This takes
care of all the internal faults within the protection zone at this
relay it from hv, ct to lv ct ,it is also called as Differential zone.
Fault lying within this zone are called as external fault or through
fault.
 Details of the relay
 Transformer Differential protection relay
 Percentage Bias type
 Suitable for 2 winding transformer ,CTR-iA,
 operating current 20-100%
 Bias setting 20-30% , operating time less than msec for time setting
contact 2 nos

46.  Over current earth fault protection is also
called as back up protection . It two
transformers are used in parallel than
directional Over Current Earth fault relay
should be used.
 These relay are provided on 33kv hv side of
the transformer ,11kv (lv) side of the
transformer and on 11kv feeders.

47.  It is used to provide protection against internal
faults in transformer . Incipient faults are due to
the arcing in the oil because of the failure of the
inter -lamination or core bolt insulation or poor
electrical connection causing spark in the oil.
These fault occurs the gas in the main tank
rushes upwards and gets accumulated in the
relay chamber . initially it initiates buchholz
alarm it the fault persist then buchholz trip
command is extended to the CB.

48.  Generally for 33kv S/S
 Auxiliary DC volt is 30 v DC , 15 nos of cells are used
 DC voltage supply is used for following control circuit
1) Tripping circuit of CB
2) Closing circuit of CB
3) Alarm circuit , (buchholz alarm, winding temp alarm, trip alarm
,DC fail alarm)
4) Semaphore indicator (indicators the close/open position of isobar
and CB)
5) Breaker on/off indicates (indication bulbs are used )
6) Trip circuit healthy indication (indication bulb is used )

49.  Specific Gravity of electrolyte and amount of
charged
 Hydrometer :- it is the device used for
measurement of specific gravity of electrolyte
range is 1150 to 1433.
100 75 50 25 Discharged
Specific Gravity
At 27o C
1200-1230 1200-1210 1170-1185 1150-1160 Below 1150

50.  3 ph Capacitor bank is used for improvement
of power factor . It is normally connected to 11
kv bus . VCB is used for Capacitor bank
switching .
 Normally capacitor banks are connected in star.

51.  12 KV , 1200 KVAr, 2400 KVAr , 3600 KVAr

53. The advantages of power factors improvement by
Capacitor addition:-
 a) Reactive component of the network is
reduced and so also the total current in the
system from the source end
 b) I2R power losses are reduced in the system
because of reduction in current
 c) voltage level at the load end is increased

54.  Reduced kvA (maximum demand ) charges in
utility bill.
 Reduced distribution losses (kwh) within the
plant network.
 Better voltage and improved performance of
system.
 A high power factor eliminates penalty charges
imposed when operating with a low power
factor.

55. ISO ABISO
AB
AB
3PH SUPPLY
ISO
ISO
ISO
ISO
ISO
ISO
ISO
ISO
AB
AB
R Y B
R Y B
R
Y
B
R
Y
B
R
Y
B
POWER X’MER
INCOMING BUSBAR OUTGOING BUSBAR

57. Voltage
level
(kV)
Standar
d bay
widths
(in
Mtrs.)
For equipments
and rigid
conductors in air
Phase to Phase spacing in
isolators and switches
Phase
to
phase
(mm)
Phase to
earth
(mm)
Isolator
(mm)
Switches with
Arc Horns
(mm)
132 9.5 1700 1000 2135 3050
66 7 1220 750 1525 2135
33 4.6 915 610 765 1220
11 3.5 560 305 610 915
0.415 -- 380 305 -- --

58.  The training session was very educational and
very informative this CSPDCL Office have
good harmonic relation and co-ordination
between staff members. As the vocational
training seems laborious job to gate in touch
with the activities. It was nobility of the people
to provide the information and the required
theoretical background at there continuous job
hour.