JPH0140476B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a discharge gap device for protecting a series capacitor.

<Prior Art> In series capacitor installations, protective gap devices are used to protect series capacitors from overvoltage. The currently used gap device will be explained below with reference to FIGS. 1 and 2. C ₁ and C ₂ are series capacitors, whose midpoint P ₁ is connected to the current limiting resistor R ₂ via the coupling resistor R ₁
and the connection point _P2 with the auxiliary gap PG. BPS is a bypass switch, and L is a power transmission/distribution line.

The main gaps G and G' connected in parallel to the series capacitors C ₁ and C ₂ are connected to a first gap G 1 consisting of first electrodes Ga ₁ and Gb _{1 and} an arc runner as shown in FIG. A second gap _G2 comprising second electrodes Ga ₂ and Gb ₂ supported by electrodes 1a and _1b and having a length greater than that of the first gap _G1 ; The third electrode Gb 3 forms a third gap G ₃ together with _the second electrode Ga ₂ and is housed in a cubicle 3 having an ionized gas discharge hole 2 .

The one first electrode Ga ₁ is insulated from the cubicle 3 via a bushing 4, and the other first electrode Gb ₁ is attached to the cubicle 3 via a bushing 5.

Further, the third electrode Gb ₃ is supported by the cubicle 3 with an insulator 6, and is connected to the cubicle 3 via the upper horizontal conductor 7, and is also connected to the vertical conductor 8,
It is connected to the other first electrode Gb ₁ via the lower horizontal conductor 9 to form a circuit. Although Fig. 2 shows the main gap G on the series capacitor _C1 side,
The main gap G′ on the series capacitor C ₂ side is also configured in almost the same way, and the main gap G′ on the side of series capacitor C 2
The auxiliary gap PG, coupling resistor R ₁ and current limiting resistor R ₂ are housed inside the main gap G storage cubicle 3 and disposed below it. In addition, 10 is an insulated stand,
11 is an insulator.

According to the above configuration, an overvoltage is applied between the terminals of series capacitors C ₁ and C ₂ due to a short circuit current at the time of a transmission/distribution line fault, and the voltage between the terminals of series capacitor C ₂ reaches the discharge starting voltage of auxiliary gap PG. Then, this discharges and the overvoltage is applied to the main gap G side via the coupling resistor _R1 . In this main gap G, since the length of the first gap _G1 is short, the current is first fired here, and the current flows to the X-cubicle 3.
- Conductor 8 - Conductor 9 - First gap G ₁ - Bushing 4 - Y. Therefore, the first gap G ₁
The arc _a1 generated in is blown upward by the electromagnetic force of the first loop circuit I, and
1b and reaches the second gap _G2 . This ascending arc a ₂ further rises and extends upward in an arched manner in order to move to the third electrode Gb ₃ . Then, when reaching the third electrode _Gb3 , the current flows from X-cubicle 3-conductor 7-third electrode _Gb3 -second electrode _Ga2-
Arc runner 1a - first electrode Ga ₁ - bushing 4
-Flows with Y.

As the main gap G discharges, the full voltage is applied to the current limiting resistor _R2 , so the other main gap G' is also discharged in the same manner as above, and the series capacitor _C1 ,
Turn off C ₂ . Subsequently, the bypass switch BPS closes,
When the discharges in both main gaps G and G' are extinguished, the ionized gas in the cubicle 3 is quickly exhausted through the exhaust hole 2, and insulation recovery is accelerated. Even if the accident is recovered and the series capacitors C ₁ and C ₂ are reinserted into the line, the gaps G and G' will not be discharged again due to the voltage between the terminals of the series capacitors C ₁ and C ₂ during normal operation.

<Problem to be solved by the invention> By the way, as mentioned above, the first electrode Gb ₁ ,
The arc a ₁ generated between Ga ₁ is arc runner 1
It rises between b and 1a, reaches between the second electrodes Gb ₂ and Ga ₂ , becomes an arc a ₂ , and further extends upward in an arched manner to move to the third electrode Gb ₃ . The shape of the arc a ₂ between the electrodes Gb ₂ and Ga ₂ may deviate from the plane of existence of the electrodes, and therefore, there is a problem that it is difficult for the arc a ₂ to transfer to the third electrode Gb ₃ .

In view of the above-mentioned points, it is an object of the present invention to facilitate arc transfer to the upper electrode.

<Means for Solving the Problems> In order to achieve the above object, the discharge gap device for protecting a series capacitor of the present invention includes first electrodes Ga ₁ and Gb ₁ forming a first gap,
A second electrode Ga 2 is provided on top of the first electrodes Ga ₁ and Gb ₁ via an arc runner and forms a second gap with a length greater than the first gap _.
Gb ₂ and a third electrode Gb 3 forming a third gap between the second electrode Ga ₂ and one side Ga ₂ of the second electrode above the second electrode Ga ₂ and Gb ₂ are disposed on the same vertical plane, A conductor connecting the other side Gb ₁ of the first electrode and the third electrode Gb ₃ is divided into two parts in parallel, and the two-part conductor is divided into two parts symmetrically with respect to one vertical plane on which each of the electrodes exists. It is characterized in that it is arranged in a direction opposite to the direction of one side Ga ₂ of the second electrode from the other side Gb ₂ of the two electrodes.

<Operation> According to the above configuration, the arc a 2 between the second electrodes Gb ₂ and Ga ₂ extends in a large arch upward, and even if this arc _{a 2 deviates} from the electrode existence plane, this large upward The second of the arc a ₂ that arched towards
The electromagnetic forces F ₁ and F 2 from the vertically divided conductors 8-1 and 8-2 act strongly on the vertical component on the electrode Gb ₂ side, pushing the arc _{a 2 back} onto the surface where the electrode exists. In other words, when the arc _a2 is on the electrode existence surface, the electromagnetic force from the divided conductors 8-1 and 8-2
F ₁ and F ₂ are balanced, and when arc a ₂ deviates from the electrode existing surface, for example, an arc appears on the divided conductor 8-1 side.
When a ₂ swings, the electromagnetic force F ₁ generated by the divided conductor 8-1 acts largely on the vertical component on the second electrode Gb ₂ side, pushing it back.

<Example> An example of the present invention will be described with reference to FIGS. 3 and 4. Note that the same reference numerals as in FIG. 2 indicate the same or corresponding parts. As can be easily understood from FIG. 3, conventional conductor 7 connecting between third electrode Gb ₃ and first electrode Gb ₁ ,
8 and 9 are each a single conductor, and the divided conductor 7-
It is divided into two parts such as 1, 7-2, 8-1, 8-2, 9-1, and 9-2, and is bent into a roughly U-shape so that each electrode is symmetrical with respect to one vertical plane. And one side of the second electrode from the other side Gb ₂ of the second electrode
It is placed in the opposite direction to the direction of Ga ₂ .

<Effects of the Invention> According to the present invention, since the conductor is divided into two parts and the electromagnetic force thereof is utilized, the arc transfer to the upper electrode becomes easy and reliable.

[Brief explanation of drawings]

Fig. 1 is an electrical connection diagram showing an example of series capacitor equipment, Fig. 2 is a side view schematically showing a discharge gap device, and Figs. 3 and 4 are a schematic perspective view and a plan view showing an embodiment of the present invention. It is a diagram. Gb ₁ , Ga ₁ ... first electrode, Gb ₂ , Ga ₂ ... second electrode, Gb ₃ ... third electrode, 3 ... cubicle, 7
-1, 7-2, 8-1, 8-2, 9-1, 9-2
...divided conductor, F ₁ , F ₂ ... electromagnetic force.

Claims (1)

[Claims] 1 First electrodes Ga ₁ , Gb ₁ forming a first gap
A second electrode is provided above the first electrodes Ga ₁ and Gb ₁ via an arc runner and forms a second gap with a longer distance than the first gap.
Ga ₂ , Gb ₂ and a third electrode Gb ₃ which forms a third gap between Ga ₂ and Ga ₂ on one side of the second electrode above the second electrodes Ga 2 and Gb ₂ are arranged on the same vertical plane. established,
A conductor connecting the other side Gb ₁ of the first electrode and the third electrode Gb ₃ is divided into two parts in parallel, and the two-part conductor is divided into two parts symmetrically with respect to one vertical plane on which each of the electrodes exists. A discharge gap device for protecting a series capacitor, characterized in that the discharge gap device is arranged in a direction opposite to one side Ga ₂ of the second electrode from the other side Gb ₂ of the two electrodes.