TECHNICAL FIELD

The present disclosure relates to a gas-insulated switchgear.

BACKGROUND ART

A gas-insulated switchgear installed in a substation or the like has a structure in which bushings of three phases, which are overhead wire power receiving parts, are attached to a container in which a circuit breaker, a disconnector, etc., are housed and that is filled with insulating gas. In a conventional structure, in order to ensure air insulation distances between the bushings of the three phases, the central bushing among the bushings aligned in a line is made high, and the bushings on both sides are inclined. However, arranging all the bushings of the three phases vertically, or attaching at least bushings of two phases to side surfaces of the container, in order to facilitate bushing installation and in order to increase earthquake-resistant strength, is disclosed (see Patent Document 1).

Moreover, a structure, in which a common attachment member for attaching bushings for the three phases to a container is used in order to facilitate the installation of the bushings and the bushings are inclined such that end portions of the bushings are spaced apart from each other in order to ensure insulation distances between the bushings of the three phases, is disclosed (see Patent Document 2).

CITATION LIST

Patent Document

Patent Document 1: Japanese Laid-Open Utility Model Publication No. 59-30610

Patent Document 2: Japanese Laid-Open Patent Publication No. 2000-232707

SUMMARY OF THE INVENTION

Problems to be Solved by the Invention

The conventional gas-insulated switchgear is formed as described above, and, for example, the bushings of the three phases aligned in a line are appropriately installed so as to face in a power receiving lead-in direction, and insulation distances are ensured between lead-in wires to the bushings of the three phases. However, if the power receiving lead-in direction is changed, insulation distances cannot be ensured with the bushing arrangement being unchanged in some cases, so that the structure of the overhead wire power receiving parts needs to be changed. Therefore, there is a problem that the power receiving lead-in direction cannot be easily changed.

Moreover, when the orientation of the gas-insulated switchgear is restricted at the installation location, there is a problem that it is necessary to design a bushing structure according to the installation orientation of the container and the power receiving lead-in direction each time the installation is made.

The present disclosure discloses a technology for solving the above-described problems, and an object of the present disclosure is to provide a gas-insulated switchgear having a bushing arrangement that can flexibly respond to a power receiving lead-in direction without changing a structure.

Solution to the Problems

A gas-insulated switchgear according to the present disclosure includes: a main body portion in which a switching device is housed; power receiving lead-in bushings of three phases to which conductor portions extended rearward from the main body portion are connected, respectively; and a bushing tank at which the power receiving lead-in bushings of the three phases are provided and in which insulating gas is sealed, wherein an upper surface portion of the bushing tank is formed as a hemispherical portion protruding upward, the power receiving lead-in bushings of the three phases are provided at the hemispherical portion, the power receiving lead-in bushings of the three phases are disposed on an upper surface of the bushing tank at equal intervals in a circumferential direction such that end portions thereof are inclined outward so as to be separated from each other, and one of the power receiving lead-in bushings of the three phases is disposed along a front-rear direction of the main body portion.

Effect of the Invention

In the gas-insulated switchgear according to the present disclosure, since the power receiving lead-in bushings of the three phases are disposed at equal intervals in the circumferential direction such that the end portions thereof are inclined outward so as to be separated from each other, and one of the bushings of the three phases is disposed along the front-rear direction of the main body portion in which the switching device is housed, it is possible to ensure insulation distances without depending on a power receiving lead-in direction, so that it is unnecessary to change the structure of the bushings.

