The electrical power system is divided into 3 parts as shown-
Electricity is generated at generating station, there is a different types of generating stations such as thermal power plants, hydropower plants, nuclear power plants etc. Then the power is transmitted through the transmission line by step up or step down the voltage level to the consumer by means of distribution.
Now-a-days, 3-phase, 3-wire a.c. the system 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, the overhead system is adapted for transmission and distribution of electric power.
 |
| Structure of Electrical Power System |
(i) Generating station:
The electricity is generated in the power system by the alternator which operates in parallel with each other. The voltage usually generated by the alternator is about 11kv, for economical operation of power system the voltage is step up by means of a step-up transformer up to 132kv fro 11kv.
(ii) Primary transmission:
After generation of electricity from generating station by the alternator of 11kv is step up to 132kv by step-up transformer then it is transmitted by 3 phase 3 wire overhead line in the form of primary transmission.
(iii) Secondary transmission:
After primary transmission, the primary transmission line is terminated at receiving station. At the receiving station, the voltage level of 132kv is reduced to 33kv by means of the step-down transformer. At the station, 33kv is transmitted to the various substation in form of secondary transmission.
(iv) Primary distribution:
After the complete journey of secondary transmission, the secondary transmission line is terminated at the
Substation where the voltage level down by step down transformer from 33kv to 11kv.
(v) Secondary distribution:
The secondary voltage level of primary distribution(11kv) is given to the secondary distribution, where the voltage is down up to 400v by means of the step-down distribution transformer by 3 phase 4 wire system to the consumer.
People also like:
