This document provides an overview of grid substations. It discusses how substations receive power from generating stations and transmission lines and transform voltages to suitable levels for distribution. It also describes the key components of substations, including transformers, circuit breakers, and earthing systems. Classification of substations by voltage level and indoor/outdoor design is covered. The purpose and components of transmission lines, including conductors, insulators, towers, and earth wires, are summarized as well.
4. Classification based on voltage levels,
e.g. : A.C. Substation : EHV, HV, MV,
LV; HVDC Substation.
Classification based on Outdoor or
Indoor : Outdoor substation is under
open sky. Indoor substation is inside a
building.
5. Primary Substations receive power
from EHV lines at 400KV, 220KV,
132KV and transform the voltage to
66KV, 33KV or 22KV to suit the
local requirements .
6. Secondary Substations receive
power at 66/33KV which is
stepped down usually to 11KV.
Distribution Substations receive
power at 11KV, 6.6 KV and step
down to a volt suitable for LV
distribution purposes, normally
at 415 volts
11. Conductor
Earth wire
Insulator
Transmission Tower
Wave trap and other hardware(Clamp,
Spacer, Vibration dampers, connectors etc.
12.
13. Used to reduce earth wire potential
and stress on insulators at the time
of stroke and also for safety
Earth resistance depend upon soil
resistivity(general 100 Ω-m)
14. It provides a surface under the
substation which has uniform potential
nearly equal to zero or Absolute Earth
Potential.
It is of two types
o Neutral Earthing
o Equipment Body Earthing
25. Insulator are required to
support the line conductor and
provide clearance from ground
and structure.
26.
27.
28.
29. A Transformer is a static
device that transfers Electrical
energy from one Electrical
circuit to another Electrical
circuit by means of a common
Magnetic Circuit.