Classification of Power Substations

This set of vocabulary flashcards covers the classification of power substations based on application, service, operating voltage levels, and design/location as described in the lecture notes.

Transmission Substation

A hub acting as a crucial intersection that connects two or more transmission lines on the electrical superhighway.

Distribution Substation

The link between the high-voltage transmission grid and local users that reduces voltage from transmission levels (e.g., $115\,kV$) to medium voltage ranging from $2.4\,kV$ to $33\,kV$.

Collector Substation

A central hub common in renewable energy projects like wind farms that collects power from multiple generating units and steps up the voltage for grid transmission.

Converter Substations

Considered the "translators" of the grid, these substations switch electricity between Alternating Current (AC) and Direct Current (DC) and can change current frequency.

Switching Station

Also known as a switchyard, it focuses on connecting, disconnecting, and rerouting power lines and equipment without altering voltage levels.

Step-up Substation

Substations connected to power generating stations that increase generated voltages to higher levels, such as $69\,kV$ to $1500\,kV$ AC, for efficient long-distance transmission.

Step-down Substation

Substations that bridge the gap between bulk power transmission and localized community needs by ensuring electricity arrives at a safe and accessible voltage.

Primary Substation

Substations linked with bulk load centers along primary transmission lines that step down voltage for the purpose of secondary transmission.

Secondary Substation

Substations located along secondary transmission lines adjacent to loads where voltages are further stepped down for distribution.

$34,500Y/19,920$-volt system

A three-phase circuit with a grounded neutral where the voltage between phases is $34,500\,V$ and the single-phase voltage from phase to neutral is $19,920\,V$.

Mobile Substation

A temporary power source used for giant construction projects, characterized by easy maintenance and protection from blackouts, fires, and sabotage.

Industrial Substation

Also referred to as bulk substations, these are distributive substations designed for dedicated consumers requiring bulk power supply.

Mining Substation

A distinct substation requiring high precautionary safety measures, dedicated to controlling electrical power supply from the surface to underground mine stations.

High Voltage Substations (HV Substations)

Substations involving operating voltage levels between $11\,kV$ and $66\,kV$.

Extra High Voltage Substations (EHV)

Substations involving operating voltage levels between $132\,kV$ and $400\,kV$.

Ultra-High Voltage (UHV)

Substations with an operating voltage above $400\,kV$.

Direct-current high voltage (dc HV)

Substations with operating voltage levels of $\pm 250\,kV$, $\pm 400\,kV$, or $\pm 500\,kV$.

Outdoor Substation

Substations constructed in the open air, typically for high voltage systems such as $66\,kV$, $132\,kV$, $220\,kV$, and $400\,kV$.

Indoor Substation

Substations built under a roof or closed compartment, generally operating at lower voltages such as $11\,kV$ and $33\,kV$.

Pole Mounted Substation

The cheapest form of outdoor substation for voltages not exceeding $11\,kV$ (or $33\,kV$), with equipment installed on H-pole or 4-pole structures.

Underground Substation

Substations built in ground or subversive spaces in congested areas where land cost is high, typically operating between $34500/19920\,V$ and $4160/2400\,V$.