4. 132kv incoming lines through Lightning Arrestor & is132kv incoming lines through Lightning Arrestor & is
connected to the Gantry through insulated discs.connected to the Gantry through insulated discs.
Disc insulators
Lightning
Arrestor
Incomer
gantryLightning
Arrestors
Bus bar for all 3
incomer & 1
outgoing line
5. It is connected between the line and earth so diverts the incoming
high voltage wave to earth.
Lightning arresters act as safety valves designed to discharge
electric surges resulting from lightning strokes, switching or other
disturbance .
LIGHTNING ARRESTERS
6. The communication device used for the
communication over the power lines is a MODEM,
commonly known as Power Line MODEM (PLM).
It works as both transmitter and receiver, i.e., it
transmits and receives data over the power lines
7. Coupling Capacitor
The modulated carrier is let into power line through coupling
capacitor specially designed to with stand line voltage under all-
weather condition. The upper end of the coupling capacitor is
connected directly to the line and the lower end is connected to
the ground through a carrier frequency chock coil or drain coil.
Thus coupling capacitor forms the link between the PLCC
equipment and power line. The coupling capacitor used in
UPSEB is 2200pf capacitance
8. Wave Trap or Line Trap
Wave trap is connected in series with power line between the point of connection of
coupling capacitor and S/S. Wave trap offers negligible impedance to HF carrier. Wave
trap stands electromechanically and thermally for short circuit current in the event of fault
on the line. On the basis of blocking frequency bank, the wave trap can be following
type:
All wave
Single Frequency
Double Frequency’
Broad Band
9. CURRENT TRANSFORMER
A current transformer (CT) is used for measurement of alternating electric
currents. When current in a circuit is too high to apply directly to
measuring instruments, a current transformer produces a reduced current
accurately proportional to the current in the circuit, which can be
conveniently connected to measuring and recording instruments. A
current transformer isolates the measuring instruments from what may be
very high voltage in the monitored circuit.
10. The line ,through the isolators is distributedThe line ,through the isolators is distributed
in the s/s through Main bus.in the s/s through Main bus.
Main Bus bar
132kv Bay
11. POTENTIAL OR VOLTAGE TRANSFORMER
Voltage transformers (VT) (also called potential transformers (PT)) are a
parallel connected type of instrument transformer, used for metering and
protection in high-voltage circuits or phasor phase shift isolation. They are
designed to present negligible load to the supply being measured and to
have an accurate voltage ratio to enable accurate metering. A potential
transformer may have several secondary windings on the same core as a
primary winding, for use in different metering or protection circuits
16. Control roomControl room
The control room is nerve center of a power station .
The various controls performed from here are voltage adjustment, load control, emergency
tripping of turbines etc.