JPS6235328B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to grounding tanks of gas insulated electrical equipment.

A conventional grounding system for gas-insulated electrical equipment is shown in FIG. This gas insulated electrical equipment includes a disconnector tank 1, a disconnector stand 2, a bushing tank 3, a bushing stand 4, a disconnector tank 5, a disconnector stand 6, a current transformer tank 7, and a current transformer stand (not shown). ), a circuit breaker tank 8, a circuit breaker stand 9, a current transformer tank 10, a current transformer stand (not shown), a disconnector tank 11, a disconnector stand 12, a bushing tank 13, and a bushing stand 14. is installed in a π-shape as shown in Figure 1. A main grounding wire 22, which is part of a grounding network connected to a grounding point, is installed in a straight line below the ground. The grounding wire 25 of the disconnector tank 1 is connected to this main grounding wire 22,
Ground wire 16 of bushing tank 3, ground wire 17 of disconnector tank 5, ground wire 18 of circuit breaker tank 8,
19, the ground wires (not shown) of the current transformer tanks 7 and 10, the ground wire 20 of the disconnector tank 11, and the ground wire 21 of the bushing tank 13 are connected.

Note that each tank is made of metal, and contains a current-carrying conductor constituting each tank and an insulating gas sealed therein. With such a grounding method, the loop of the ground wire current flowing through the circuit breaker tank 8 is the loop between the circuit breaker tank 8 and the circuit breaker ground wire 1.
8 - Main grounding wire 22 - Grounding wire 19 on the other side of the circuit breaker tank 8 - The circuit breaker tank 8 forms a large loop, and the magnetic flux generated from the current-carrying conductor passes through this loop, generating a large induced voltage. Therefore, a large induced current flows through this loop, causing overheating and melting of the ground wire. In addition, these induced currents flow through each tank, increasing the temperature of the tanks and current-carrying conductors.

The present invention aims to reduce the amount of penetration of magnetic flux generated from a current-carrying conductor and eliminate the above-mentioned drawbacks of the conventional devices.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 2 shows an embodiment of the invention. In the figure, the same reference numerals as in FIG. The main grounding wire 25 is buried and the grounding wire of each tank is connected to this main grounding wire 25. Note that 23 and 24 are ground wires of the circuit breaker tank 8, which are connected to a main ground wire 25 buried underground along the vicinity directly below the circuit breaker tank 8.

With this configuration, there is no large loop as in the conventional case, and the circuit breaker tank 8 - the grounding wire 23 of the breaker tank 8 - the main grounding wire 25 - the breaker tank 8
This becomes a small loop consisting of a loop of the grounding wire 24, which reduces the amount of penetration of the magnetic flux generated by the current-carrying conductor, and reduces the induced voltage in this loop. Therefore, the current flowing through the ground wire 23 of the circuit breaker tank 8 is reduced, and the ground wire is prevented from melting and overheating.
Further, since the ground wire current flowing through the circuit breaker tank 8 is reduced, the temperature rise of the tank and the current-carrying conductor is reduced, and the tank can be made smaller.

FIG. 3 shows another embodiment of the invention.
In this embodiment, the grounding wire 26 of the circuit breaker tank 8,
27 is not connected to the main grounding line 25 near the circuit breaker, but is extended to the position of the main grounding line 25 to which the grounding lines 17, 20 of the disconnector tanks 5, 11, etc. are connected, and connected thereto. By doing so, it is possible to reduce the amount of penetration of magnetic flux generated by the current-carrying conductor, increase the impedance of the loop, and reduce the ground line current.

Note that the present invention can be applied not only to the embodiments but also to gas insulated wires and gas insulated switchgears.

As described above, according to the present invention, the current induced in the ground wire can be reduced, and overheating and melting of the ground wire can be prevented. Furthermore, a ground line current flows through the tank, and by reducing this current, loss in the tank can be reduced, and temperature rise in the tank and current-carrying conductor can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a conventional gas insulated electrical device, FIG. 2 is a perspective view showing a gas insulated electrical device according to one embodiment of the present invention, and FIG. 3 is a perspective view showing another embodiment of the present invention. It is. Note that the same reference numerals in the figures indicate the same or corresponding parts. In the figure, 1, 5, 11...disconnector tank, 2, 6,
12... Disconnector mount, 3, 13... Bushing tank, 4, 14... Bushing mount, 7, 10... Current transformer tank, 8... Circuit breaker tank, 9... Circuit breaker mount,
15-21, 23, 24, 26, 27...ground wire,
25...Main ground wire.

Claims (1)

[Claims] 1. In a gas-insulated electrical device in which a plurality of tanks containing an insulating gas and a current-carrying conductor are arranged and connected in a non-linear manner, and the tanks are connected to a grounding network buried underground, the above-mentioned grounding network is configured. A gas-insulated electrical device characterized in that a main grounding wire is installed along the arrangement of the tank, and the main grounding wire and the tank are connected by a grounding wire.