A lattice tower for high-voltage overhead transmission lines having a lattice structure is provided that includes: a base anchored to the ground; a top portion designed for anchoring first and second conductors of a high-voltage overhead transmission line; and a body which extends between the base and the top portion. The lattice tower includes a grid high-voltage electric switching substation that includes: GIS-technology-based switchgear equipment arranged within the base of the lattice structure; a first loop-in loop-out feeder connection configured to connect the first conductors of the high-voltage overhead transmission line to the GIS-technology-based switchgear equipment and made by insulated cables or GIS-technology-based ducts, or by mixed solutions wherein a first portion is made by bare conductors and a second portion is made by insulated cables or GIS-technology-based ducts; a second loop-in loop-out feeder connection configured to connect the second conductors of the high-voltage overhead transmission line to the GIS-technology-based switchgear equipment and made by insulated cables or GIS-technology-based ducts, or by mixed solutions, wherein a first portion is made by bare conductors and a second portion is made by insulated cables or GIS-technology-based ducts; and a protection, command and control system arranged within the lattice structure, or in proximity to the base of said lattice structure; wherein the GIS-technology-based switchgear equipment is designed to be connected also to a user connection line.

A lattice tower for high-voltage overhead transmission lines having a lattice structure is provided that includes: a base anchored to the ground; a top portion designed for anchoring first and second conductors of a high-voltage overhead transmission line; and a body which extends between the base and the top portion. The lattice tower includes a grid high-voltage electric switching substation that includes: GIS-technology-based switchgear equipment arranged within the base of the lattice structure; a first loop-in loop-out feeder connection configured to connect the first conductors of the high-voltage overhead transmission line to the GIS-technology-based switchgear equipment and made by insulated cables or GIS-technology-based ducts, or by mixed solutions wherein a first portion is made by bare conductors and a second portion is made by insulated cables or GIS-technology-based ducts; a second loop-in loop-out feeder connection configured to connect the second conductors of the high-voltage overhead transmission line to the GIS-technology-based switchgear equipment and made by insulated cables or GIS-technology-based ducts, or by mixed solutions, wherein a first portion is made by bare conductors and a second portion is made by insulated cables or GIS-technology-based ducts; and a protection, command and control system arranged within the lattice structure, or in proximity to the base of said lattice structure; wherein the GIS-technology-based switchgear equipment is designed to be connected also to a user connection line.

An electrical energy transmission device for the transmission of electrical energy has a fluid-holding chamber. An electrically insulating fluid is contained in the fluid-holding chamber. The electrically insulating fluid is, at least in part, air-drawn from the surroundings of the electrical energy transmission device. The insulating fluid is used for insulating phase conductors in order to avoid short circuit conditions.

An electrical energy transmission device for the transmission of electrical energy has a fluid-holding chamber. An electrically insulating fluid is contained in the fluid-holding chamber. The electrically insulating fluid is, at least in part, air-drawn from the surroundings of the electrical energy transmission device. The insulating fluid is used for insulating phase conductors in order to avoid short circuit conditions.

A switch gear system is described. In some implementations, a switch gear arrestor system can include a switch gear and one or more arrestors mounted on a non-conductive insulated bar. The one or more arrestors can be connected to one or more isolators through a respective aperture in the non-conductive insulated bar. Each arrestor can be connected to one of the one or more electrical energy sources at a first end and can be connected to one of the one or more isolators at a second end. The switch gear arrestor system can further include one or more ground leads. Each ground lead can connect one of the one or more isolators to a conductive grounding bar.

A switch gear system is described. In some implementations, a switch gear arrestor system can include a switch gear and one or more arrestors mounted on a non-conductive insulated bar. The one or more arrestors can be connected to one or more isolators through a respective aperture in the non-conductive insulated bar. Each arrestor can be connected to one of the one or more electrical energy sources at a first end and can be connected to one of the one or more isolators at a second end. The switch gear arrestor system can further include one or more ground leads. Each ground lead can connect one of the one or more isolators to a conductive grounding bar.

A multiphase switchgear includes a switch panel, a vertical input housing module and a vertical switch housing module. The switch housing module and the input housing module are spaced apart from one another by a transverse housing module. The input housing module, the transverse housing module and the switch housing module form a first phase block. A plurality of phase blocks are located flush one behind the other in the direction of the transverse housing.

A gas insulated switching apparatus includes a transformer line unit and a power transmission and reception line unit adjacent to each other. The power transmission and reception line unit includes two cable heads. The cable heads are arranged at an interval between units in an extension direction in which a bus-bar extends, and the cable head is disposed in a space behind the transformer line unit.

A gas insulated switching apparatus includes a transformer line unit and a power transmission and reception line unit adjacent to each other. The power transmission and reception line unit includes two cable heads. The cable heads are arranged at an interval between units in an extension direction in which a bus-bar extends, and the cable head is disposed in a space behind the transformer line unit.

The invention relates to a removable stabilizer for a spacer casing (24a-24f) of an electrical installation of the GIS type (20), the spacer casing (24a-24f) comprising a first opening (33) as well as a conductor (30b) provided with a bore (34), the removable stabilizer (29) comprising a plug (29a) configured to be introduced via the first opening (33) into the spacer casing (24a-24f), the plug being designed to penetrate into the bore (34) of the conductor (30b) so as to block said conductor (30b) against moving in translation after said spacer casing (24a-24f) has been put to atmospheric pressure.