JP2545421B2 - Support structure of discharge electrode in lightning arrester device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention, when an abnormally large current flows through a power transmission line due to lightning, discharges it rapidly to the ground by a lightning protection function and suppresses follow-up current. The present invention relates to a support structure for a discharge electrode in a lightning arrester device capable of blocking and preventing a permanent ground fault.

(Prior Art) Conventionally, a lightning arrester device for a power transmission line has a lightning arrestor suspended and fixed to a support arm of a steel tower by a mounting adapter, and a lightning side electrode metal fitting provided at a lower end portion of the lightning arrester , A ground-side discharge electrode in the form of a horn is provided, while a power-supply-side discharge electrode made of steel in the form of a horn is also provided in the wire suspension fitting on the transmission line side, for example. The air discharge gap is set to have an insulation strength that can withstand the frequency voltage and the switching surge voltage. Then, when a lightning surge enters the power transmission line, the surge current flashes through the air discharge gap, and flows through the current limiting element having a non-linear voltage-current characteristic housed inside the lightning arrestor, and the supporting arm. And it is discharged through a steel tower.

(Problems to be solved by the invention) Since the discharge electrode on the side of voltage application is entirely formed of steel and is cantilevered with respect to the hanging metal fitting, for example, the voltage class has a length of 275 KV for length. The diameter was 2.5m, the diameter was about 40mm, and the weight was about 40kg, and there was a problem that it took time to carry it in mountainous areas and install it on a tower. If the discharge electrode becomes heavier and swings under a wind pressure load, a large bending moment is applied to the mounting part due to inertial force and the material diameter must be increased, or special reinforcement must be applied to prevent vibration fatigue. was there.

Furthermore, if the discharge electrode becomes heavier, the support insulator device of the transmission line becomes unbalanced.To prevent this, it is located on the side opposite to the discharge electrode with respect to the hanging fitting, and the surface insulator of the support insulator flashes. The weight of the arcing horn has been increased to prevent entanglement. For this reason, the load acting on the lower end of the supporting insulator becomes large, and when the power transmission line swings due to wind pressure, the inertial force at the lower end of the supporting insulator becomes large, and the supporting insulator tends to swing irregularly and the clearance is There is a problem that electrical and mechanical reliability may be deteriorated due to shortage or abnormal stress generated in the member.

An object of the present invention is to reduce the weight of the discharge electrode attached to the transmission line side, to facilitate the transportation of the discharge electrode and the attachment of the discharge electrode to a steel tower, and to suppress the irregular shaking of the support insulator. In addition, the present invention provides a support structure for a discharge electrode in a lightning arrester device, which can sufficiently secure an insulation clearance, prevent abnormal stress from occurring, and improve electrical and mechanical reliability.

Configuration of the Invention (Means for Solving the Problems) In order to solve the above problems, the present invention suspends a support insulator with respect to a support arm of a steel tower, and a suspension metal fitting is provided at a lower end portion of the support insulator. The transmission line is supported by the transmission line, and a part of the horn-shaped discharge electrode on the charging side of the transmission line is connected and supported by the support mechanism to the transmission line. A means for supporting the insulator, attaching a discharge electrode on the ground side to the lower end of the lightning insulator, and providing a predetermined discharge gap with the discharge electrode on the charging side is adopted.

(Operation) The present invention operates as follows by adopting the above means.

The discharge electrode is supported at two points by the support mechanism connected to the suspension metal fittings and the power transmission line.Since the cantilever part from the support point of the support mechanism to the tip of the discharge electrode is short, inertia during shaking Bending moments due to force and self-weight are reduced.
As a result, the material diameter of this portion can be reduced, and if the material having a reduced diameter is used between the support points, sufficient strength can be secured, and the discharge electrode as a whole can be reduced in weight. As a result, transportation and mounting work on the steel tower are facilitated.
In addition, since the discharge electrode can be made lighter, the weight of the arcing horn for preventing the surface flashover of the supporting insulator supported by the hanging metal fitting can be reduced, and therefore, the irregular shaking of the supporting insulator can be suppressed and the insulation can be prevented. It is possible to secure a sufficient clearance, prevent abnormal stress from occurring, and improve electrical and mechanical reliability.

(Embodiment) An embodiment embodying the present invention will be described below with reference to FIGS. 1 to 4.

As shown in FIG. 1, a connecting fitting 2 is fixed to the tip of a support arm 1 of a steel tower, and a suspension insulator 5 is connected in series to the connecting fitting 2 via a U Grevis link 3 and a horn mounting fitting 4. A suspension insulator series 6 as a supporting insulator is supported so as to be swingable in the line direction (the left-right direction in FIG. 1) and the orthogonal direction (the direction orthogonal to the paper surface of FIG. 1). A connecting link 8 is attached to the horn mounting bracket 7 at the lower end of the suspension insulator string 6.
An electric wire clamp 10 that supports the power transmission line 9 is supported via the. The horn mounting brackets 4 and 7 are equipped with arcing horns 11 and 12 for reducing damage to the surface flashover of the suspension insulator string 6 as much as possible. In this embodiment, the horn mounting bracket 7, the connecting link 8 and the electric wire clamp are used.
The suspension metal fitting K of the power transmission line 9 is formed by 10.

A mounting adapter 13 is fixed to the tip of the support arm 1 by a bolt, and a first lightning insulator 14 is fixed to the lower surface of the tip of the adapter 13 with an electrode fitting 15 on the ground side. In addition, the grounding-side electrode metal fitting 15 of the second lightning protection insulator 17 is fixed to the lower end portion of the first lightning protection insulator 14, that is, the electrode fitting 16 on the charging side by bolts.

The first and second lightning protection insulators 14 and 17 are mainly made of a pressure-resistant insulating cylinder (not shown) formed in a cylindrical shape by a tension-resistant material such as FRP, and zinc oxide (ZnO) housed in series therein. A current limiting element (not shown) having a non-linear voltage-current characteristic as a material, and a cap-shaped charge-side and ground-side electrode metal fittings 16 and 15 fitted and fixed to both ends of the withstand voltage insulating cylinder. Further, it is integrally formed by a rubber mold 18 provided on the outer circumference of the pressure-proof insulating cylinder.

In addition, arcing rings 19 and 20 are attached to the respective electrode fittings 15 and 16 by a support arm to reduce damage when the rubber mold 18 is flashed on the surface. A discharge electrode 21 on the ground side is attached to the electrode metal fitting 16 on the charging side of the second lightning protection insulator 17.

On the other hand, the charging side horn mounting member 7 supports a discharging side discharge electrode 22 that faces the grounding side discharge electrode 21 and forms a predetermined air discharge gap G. As shown in FIG. 2, the discharge electrode 22 is formed into a flat hairpin shape, and a pair of brackets are rotatably connected to a mounting plate 23 fixed to the horn mounting bracket 7 by a connecting pin 24. It is welded and fixed to 25. Also, this discharge electrode 22
A support mechanism 26 for supporting the discharge electrode 22 on the power transmission line 9 is interposed between the power transmission line 9 and the power transmission line 9.

The structure of the support mechanism 26 will be described with reference to FIGS. 3 and 4. In the transmission line 9, the upper and lower halves of the metal fittings 27, 2 are used.
8 is tightened and fixed by bolts 29, and a bracket 27a is formed on the upper grip 27. Also, the discharge electrode 22
A bifurcated bracket 30 is welded and fixed to the lower surface of the middle part of the bracket 30, and the bracket 30 and the bracket 27a of the holding metal fitting 27 are fixed.
A rod-shaped upper and lower length-adjusting metal fitting 31 is connected to the, and both ends thereof are rotatably fixed by bolts 32 and 33. The head of the bolt 32 and the bolt
The nut 34 screwed to the 32 is formed in a substantially hemispherical shape to prevent corona discharge. Similarly, the gripping metal 27, 28
Ribs 27b and 28a are formed to relax the electric fields of the bolts 29 and 33 and prevent corona discharge.

Further, the end portion of the length adjusting fitting 31 and the sleeve 35 are screw-connected, and after adjusting the length, they are fixed with nuts at both ends.

On the other hand, since the discharge electrode 21 on the ground side is not shown, it is formed in an arc shape when viewed from the line direction.
Is the direction orthogonal to the line in Fig. 3 (direction orthogonal to the paper surface of the same figure)
The discharge gap G is kept substantially constant even if the discharge gap G is swung.

Next, the operation of the transmission line lightning arrester device configured as described above will be described.

Now, when a large current is applied to the power transmission line 9 due to a lightning stroke, this current flows from the wire clamp 10, the connecting link 8, the horn mounting bracket 7, the bracket 25 and the discharge electrode 22 to the discharge gap G.
Is discharged to the discharge electrode 21 through the flow path, flows from the electrode fitting 16 to the current limiting element (not shown) of the second lightning protection insulator 17, and the electrode fitting 15, 1
6, the current limiting element (not shown) of the first lightning protection insulator 14, electrode fitting 1
It flows to the support arm 1 through 5 and the mounting adapter 13, and further flows to the steel tower and is discharged to the ground. The subsequent current generated thereafter is suppressed and cut off by the current limiting element.

In the embodiment of the present invention, since the discharge electrode 22 on the voltage applying side is supported on the power transmission line 9 by the supporting mechanism 26, it means that the discharge electrode 22 is supported at two points, that is, the base end and the middle of the discharge electrode 22. Bending moments are reduced. As a result, the material diameter of this portion can be reduced, and if the material having a reduced diameter is used between the support points, sufficient strength can be secured, and the discharge electrode as a whole can be reduced in weight. As a result, transportation and mounting work on the steel tower are facilitated.

Further, in the embodiment of the present invention, since the weight of the discharge electrode 22 can be reduced, the weight of the arcing horn 12 for preventing the surface flashover of the suspension insulator string 6 attached to the horn attachment 7 can be reduced. Therefore, it is possible to suppress irregular swinging of the suspension insulator to secure a sufficient insulation clearance, and to prevent abnormal stress from occurring to improve electrical and mechanical reliability.

The position of the support point of the discharge electrode 22 may be selected in consideration of the length and shape of the discharge electrode and the catenary angle of the electric wire so that the discharge electrode and the support mechanism as a whole are most rational in terms of size and weight reduction. .

The present invention is not limited to the above embodiment, but can be embodied as follows.

(1) In the embodiment shown in FIG. 1, the support mechanism 26 is provided corresponding to the tip of the discharge electrode 22, or the support mechanism 26 is provided at a plurality of locations.

(2) As shown in FIG. 5, the grips 36 are attached to the two power transmission lines 9.
The support plate 37 is installed on the grip fitting 36, the discharge electrode 22 on the power-supply side is supported on the support plate 37, and the discharge electrode 22 and the horn mounting bracket 7 on the power-supply side are attached. Electrically connect with lead wire 38. The other actions and effects are the same as those in the above embodiment.

EFFECTS OF THE INVENTION As described above in detail, according to the present invention, the entire discharge electrode is lightened, and as a result, the transportation and the mounting work on the steel tower can be easily performed. In addition, since the discharge electrode is lightweight, the arcing horn for balancing with the discharge electrode can also be lightweight, reducing the overall load on the lower end of the support insulator to reduce the inertial force and reduce the swing angle of the support insulator. There is an effect that it is small and the swing time is shortened, and the insulation clearance between the power transmission line and the steel tower can be secured.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the entire lightning arrester device embodying the present invention, FIG. 2 is a plan view showing a discharge electrode on the charging side and an arcing horn, and FIG. 3 is A in FIG. -A line sectional view, FIG. 4 is a BB line sectional view of FIG. 3, and FIG. 5 is a perspective view of a main part showing another example of the present invention. 1 ... Support arm, 6 ... Suspended insulator string as support insulator, 9 ... Transmission line, 12 ... Arcing horn, 13 ... Mounting adapter, 14 ... First lightning arrester, 15 ... Ground side Electrode metal fittings, 16 …… Electrode metal fittings for home appliances, 17 …… Second lightning arrester, 21 …… Grounding side discharge electrode, 22 …… Discharge side discharging electrode, 23 …… Mounting plate, 24 …… Coupling Pins, 25, 30 …… Brackets, 26 …… Support mechanism, 27,28 …… Grip fittings, 29,32,33
...... Bolts, 35 ...... sleeve, K ...... Horn mounting bracket 7, connection link 8 and electric wire clamp 10 suspending bracket for transmission line.

Claims (4)

(57) [Claims] 1. A support insulator is suspended from a support arm of a steel tower, and a transmission line is supported at a lower end portion of the support insulator via a suspending metal, and one of discharge electrodes on a power-supply side having a horn shape. Part is connected and supported to a power transmission line by a support mechanism, while a lightning protection insulator is supported on the support arm side via a mounting adapter, and a ground side discharge electrode is attached to the lower end of the lightning protection insulator. A support structure for a discharge electrode in a lightning arrester device, characterized in that a predetermined discharge gap is provided between the discharge electrode on the power side. 2. A base end portion of the discharge electrode (22) is supported by a connecting pin (24) so as to be vertically rotatable with respect to a suspending metal fitting on the charging side, and an upper end portion of the support mechanism (26) is Discharge electrode (2
It is connected to 2) by a bolt (32) so as to be rotatable in the vertical direction, and the lower end is connected by a bolt (33) so as to be rotatable in the vertical direction with respect to a grip fitting (28) provided on the power transmission line (9). Further, the support mechanism (26) is provided with a length adjusting fitting (31).
The support structure for the discharge electrode in the lightning arrester device according to claim 1, wherein 3. The support mechanism (26) is fixed to a middle portion of a split metal fitting (27, 28) fixed to a power transmission line (9) and a discharge electrode (22) on the side of charging. Brackets (30)
And further, the grips (27, 28) and the bracket (3
The support structure for the discharge electrode in the lightning arrester device according to claim 1, further comprising a length adjusting metal fitting (31) connected to (0). 4. A support plate (37) as a support mechanism is attached to the power transmission line (9) via a gripping metal fitting (36), and the discharge electrode (22) is cantilevered on the attachment plate (37). The discharge electrode support structure in the lightning arrester device according to claim 1, wherein the discharge electrode (22) and the suspending metal fitting on the charging side are connected by a lead wire (38).