Electrical Power Supply System

1. ELECTRICAL TECHNOLOGY
Topic: Electrical Power Supply System
By
SUBHASIS MUKHOPADHYAY
Lecturer EE

2. Introduction
In early days, there was a little demand
for electrical energy so that small power
stations were built to supply lighting and
heating loads.
This has shifted the site of power stations
to places quite away from the consumers.
The electrical energy produced at the
power stations has to be supplied to the
consumers. There is a large network of
conductors between the power station and
the consumers.

4. Efficiency of Conventional Power
Plant
Steam Power Station
(Thermal Power Station)
Efficiency-23% to25%
Hydro-electric Power Station
Efficiency-85%
Nuclear Power Station
Efficiency-25%

5. ELECTRIC SUPPLY SYSTEM
 The conveyance of electric power from a power station to
consumers premises is known as electric supply system.
 An electric supply system consists of three principal components ,
the power station, the transmission lines and the distribution system.
Electric power is produced at the power stations which are located at
favorable places, generally quite away from the consumers. It is then
transmitted over large distances to load centers with the help of
conductors known as transmission lines.
Finally, it is distributed to a large number of small and big consumers
through a distribution network.

6.  The electric supply system can be broadly
classified into (i) d.c. or a.c. system (ii)
overhead or underground system.
 Nowadays, 3-phase, 3-wire
a.c. system is universally adopted for
generation and transmission of electric
power as an economical
proposition.
 However, distribution of electric power
is done by 3-phase, 4-wire
a.c. system.
The underground system is more
expensive than the overhead system.
Therefore, in our country, overhead
system is mostly adopted for
transmission and distribution of electric
power.

7. STANDARD VOLTAGE FOR ELECTRICAL POWER
SUPPLY
Generation voltage
6.6KV,11KV,33KV
(Normally 11KV used for Generation Voltage)
Transmission Voltage
33KV,66KV,132KV,220KV,400KV &765KV
(High voltage In India 765KV)
Distribution Voltage
Primary Distribution: 6.6KV/11KV/33KV
Secondary Distribution: A.C-415V/220V
D.C: 250V/500V

10. Block Diagram of Steam Power Station

11. Block Diagram of Hydel Power Station

12. Thank You