A hybrid switchgear is one that combines the components of traditional air-insulated switchgear (AIS) and SF₆ gas-insulated switchgear (GIS) technologies. It is characterized by a compact and modular design, which encompasses several different functions in one module.

Concept

High-voltage switchgears have been traditionally distinguished according to the medium used to extinguish the arc. In the case of the hybrid switchgear modules, this device developed during last 90’s uses two different types of technologies: one to extinguish the arc and the other to connect to the other equipment of the high voltage substation, for pursuing the goal of maximizing the advantages of the already existing technologies. The hybrid module typically utilizes

gas-insulated switchgear In an electric power system, a switchgear is composed of electrical disconnect switches, fuse (electrical), fuses or circuit breakers used to control, protect and isolate electrical equipment. Switchgear is used both to de-energize equipment t ...

components and conventional air-insulated

bushing Bushing may refer to: *Bushing (bearing), a type of plain bearing *Bushing (electrical), an insulated device that allows a conductor to pass through a grounded conducting barrier *Bushing (isolator), a mechanical device used to reduce vibrational ...

s for connecting to the

busbar In electric power distribution, a busbar (also bus bar) is a metallic strip or bar, typically housed inside switchgear, panel boards, and busway enclosures for local high current power distribution. They are also used to connect high volt ...

Components

The term module refers to the fact that the equipment itself is a combination of different standard substation components in a single assembly. The integration allows to reduce the overall substation footprint from 50% to more than 70% when compared to substation realized using conventional air insulated equipment.
An hybrid module can incorporate: * One (or more)

circuit breaker A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by an overcurrent or short circuit. Its basic function is to interrupt current flow to protect equipment and to prevent the risk ...

* One (or more)

disconnector In electrical engineering, a disconnector, disconnect switch or isolator switch is used to ensure that an electrical circuit is completely de-energized for service or maintenance. They are often found in electrical distribution and industrial a ...

and earthing switch * Gas-insulated voltage transformers * Cast-resin

current transformer A current transformer (CT) is a type of transformer that is used to reduce or multiply an alternating current (AC). It produces a current in its secondary which is proportional to the current in its primary. Current transformers, along with volt ...

s * Air- or gas-insulated

surge arrester A 'surge protector'' (or spike suppressor, surge suppressor, surge diverter, surge protection device (SPD) or transient voltage surge suppressor (TVSS) is an appliance or device intended to protect electrical devices from voltage spikes in alt ...

s The high voltage live parts (circuit breaker, disconnector and earthing switch) are encapsulated in a grounded aluminum tank, filled with pressurized

sulfur hexafluoride Sulfur hexafluoride or sulphur hexafluoride (British spelling) is an inorganic compound with the formula SF6. It is a colorless, odorless, non- flammable, and non-toxic gas. has an octahedral geometry, consisting of six fluorine atoms attached ...

(SF₆) gas, which means that the disconnector contacts will likely not require any maintenance during the product life, thus increasing the availability of the substation and the safety of the operators.

Substation applications

This modular approach to the construction of the substations is based on flexibility and customizability. The hybrid module can be used for extension or substitution in any traditional substation which uses an air-insulated busbar. This allows to configure the module with the components that are required by substation’s architecture and scope of supply. Vice versa, it is also possible to install traditional air-insulated equipment in a hybrid substation.

References

{{DEFAULTSORT:Hybrid switchgear modules Electric power Electric power distribution Electric power infrastructure Electric power systems components