Substations and Receiving Stations: Function and Classification

Summary

The document explains the role of substations and receiving stations in the electrical system, which link power production, transmission, distribution and supply. It describes how substations transform voltages between transmission and distribution levels, lists types of disconnectors, gives examples of transformer ratios, and outlines the criteria for choosing protection systems, including closed and open protections and reserve protections.

Key points

Substations transform voltage between transmission and distribution levels and act as a bridge between them.
A substation is usually located a few miles from a receiving station and distributes power to towns or areas at lower voltages (below 11 or 6 kV).
Disconnectors can be line disconnectors with grounding, bar disconnectors, or longitudinal bar disconnectors.
Transformer ratios vary depending on the protection used, for example 1200/5 A or 200/5 A.
Protection design requires detailed knowledge of the network, defined zones of influence, and defined overlap margins between protection systems.
A closed protection acts only on faults within the section limited by its measuring transformers, while an open protection acts once the setting is exceeded, regardless of fault location.
Reserve protections act when a main protection fails; they are called secondary when associated with the same switch.

Test yourself

Substations are the centers or facilities that transform the stresses of transportation or distribution tensions between transmission and distribution voltages simultaneously.

Substations in Our Region

Substations (in our region) are responsible for transforming regular or distribution voltages (25kV / 11kV). Transformer stations can be of various types and transform the voltage to low voltage distribution tension. Renewable energy installations, substations, and transformer stations are subject to compliance with regulations and standards, also typical of power companies, usually very demanding for construction and exploitation.

Substations and Receiving Stations

Substations and receiving stations are an important link between the power production, transportation, distribution, and payment or market systems. Substations act as a bridge between the power transmission and distribution system. A substation can be part of a receiving station, but generally, its mission is to work a few miles from it to control blood loss or voltage drop and power, further elevating their distribution to several towns or areas with the same voltage or voltage drops below 11 or 6 kV.

Types of Disconnectors

Disconnectors, according to their function, may be:

Line disconnector with grounding
Bar disconnector
Longitudinal bar disconnectors

Transformer Intensity

The transformation ratios can be very different depending on the type of protection that we try. For example: A 1200/5/5/5, 1200/5 A, 200/5 A.

Classification of Protection

In order to determine what protections we need in a facility, we should keep in mind the following points:

A) Detailed knowledge of the network and installation to be protected.

B) Specific definition of the zones of influence of each protection and performance for each type of disturbance expected.

C) Specific definition of margins and areas of overlap of each system of protection. The "closed" protection type will only act on faults within the section of the installation limited by measuring transformers that feed it. The "open" type, upon overcoming the adjustment, will act regardless of the status of the fault.

D) Definition of reserve guards that must act in the event of a distortion of protection associated with a main switch for each type of fault. Protections are qualified as reserve at home when they are in the same season as head protection and can be associated with my switch, in which case they are called secondary.

FAQ

What is the function of a substation?

A substation transforms voltage between transmission and distribution levels and acts as a bridge between the transmission and distribution system. It can work a few miles from a receiving station to control voltage drop and distribute power to several towns or areas.

What is the difference between a closed and an open protection?

A closed protection acts only on faults within the section of the installation limited by the measuring transformers that feed it. An open protection acts, once the setting is exceeded, regardless of the status of the fault.