2. SUBSTATION
Substation:- Substation is an intermediate switching, transforming or converting station
between the generating station and the low tension distribution network situated generally the
consumer’s load centre.
Function of the substation:- The sub-station receives power from the generating station by a single or
more feeders at a high voltage, transform the same to the different distribution voltages and sends to
different consumers through distribution network.
5. TRANSFORMER:
A transformer is a static
piece of apparatus by
means of which electric
power in one circuit is
transformed into electric
power of the same
frequency in another
circuit.
6. Specification of Transformer : Continuous rating MVA
=
32/40
Numbers of unit
=
Two(2 nos)
Phase
=
50Hz
Frequency
=
132/33 kv
Normal voltage ratio at no load =
Star/Delta
Connections
=
ᵞ nyno
Vector group
=
+5% to 15% of132 KV in
1.25% step
Tapping range
=
Type – SN
/50012/350/300/16-0CRT male
Details of C.T.
=
(1) H.V. WTI C.T.
single core ring type, 10VA ratio 205.8/1.8
class-5, fitted inside HV bushing current in 2V terminals.
(2) L.V. WTI C.T. single core ring type
10VA Ratio:- 6.99/1.8
amps class5, fitted inside L.V. bushing current in 2V terminal.
7. Cooling
=
ONAN/ONAF
Terminal arrangement
=
(1) H.V. 145KV/1250
amps, 650 BIL 300 BCT OIP
condenser bushing with arching hours. Coverage
distance:- 1300mm.
(2) L.V. 52KV/1250 amps, 250
BIL 100 BCI OIP
condensers
bushing with arching hours. Creep age
distance: - 1300.
(3) H.V. ‘N’ & L.V. ‘N’ 52KV/1250 amps
250BIL ,
100 BCT OIP condenser
bushing without arching
hours. Creep age distance:- 1300mm.
Total weight of transformer
=
73500Kg
Weight/quantity of oil
=
15000Kg/16900
8. CURRENT TRANSFORMER
Current transformers
are used for reducing
or stepping down A.C.
current from higher
value to lower for
measurement
protection or control
Types of Current Transformer:
1. Ring type C.T. or
9. VOLTAGE TRANSFORMER
Voltage transformers are
used for protection and
measurement.
Accordingly they are
either measuring type or
protective type voltage
transformers. They may
be either single or three
phases. The primary of
voltage transformer is
connected directly to
power circuit between
10. Power Transformer
Transformer is a
static
electromagnetic
machine which
transforms
alternating current
from one A.C.
voltage at same
frequency & at the
same apparent
power from one
winding via
11. Use And Application of Power Transformer:
GENERATION
TRANSMISSION
DISTRIBUTION
RECTIFIER PLANTS
12. CIRCUIT BREAKER:
It is an automatic device
capable of making and
breaking an electric circuit
under normal & abnormal
condition such as short
circuit.
13. TYPES OF CIRCUIT BREAKER:
1. Air circuit-breaker miniature circuit breaker
(ACB).
2. Oil circuit-breaker tank type or bulk oil (OCB).
3. Minimum oil circuit-breaker (MOCB).
4. Air blast circuit-breaker (ABCB).
5. Sulfur hexafluoride circuit-breaker (single
pressure or double pressure).
6. Vacuum circuit-breaker (VCB).
14. Relay:
A relay is an
electrically operated swi
tch. Relays are used
where it is necessary to
control a circuit by a
low-power signal or
where several circuits
must be controlled by
one signal. Relays were
used extensively in
15. Isolator
• Isolator can be rewritten as
isolator is a manually operated
mechanical switch which
separates a part of the
electrical power system
normally at off load condition.
16. Lightning Arrester
• A lightning arrester is placed
where wires enter a
structure, preventing damage
to electronic instruments
within and ensuring the safety
of individuals near them.
Lightning arresters, also called
surge protector.
17. Wave Trap
• It is used to trapping the high
frequency communication
signals sent on the line from
the remote substation and
diverting them to the
telecom/teleprotection panel
in the substation control room.
Line trap also is known as
Wave trap