Updated: Jul 7
Substation role in the power system
An electrical substation is a part of an electricity generation, transmission and distribution system where voltage is transformed from high to low or in reverse using transformers. It also serves as a point of connection between various power system elements such as transmission lines, transformers, generators and loads.
Warning: The content of this article is cited from The 21st Century Substation Design Guide
!!! To allow for flexibility in connecting the elements, circuit breakers are used as high power switches.
Electric power may flow through several substations between generating plant and consumer, and may be changed in voltage in several steps.
There are different kinds of substation such as Transmission substation, distribution substation, collector substation, switching substation and some other types of substation.
The general functions of a substation may include:
Connection point for transmission lines
Switchyard for network configuration
Monitoring point for control center
Protection of power lines and apparatus
Communication with other substations and regional control center
General criteria for substation design
For the substation development to reach its technical and economical potentials, the focus has moved now to studying how substations may enable more intelligence in the network, which is labeled the “smart grid” development.
Figure 1 – Different criteria for the 21st century substation design
It has been concluded that the 21st century substation design should meet the following improved criteria: reliability, security, interoperability, re-configurability, controllability, maintainability, flexibility, reduced cost and environmental impact. An estimate of the importance of the different criteria is shown in Figure 1.
The four major criteria commonly emphasized by substation designers are: reliability, cost, operational flexibility and environment impact.