CN204010854U - A kind of discharging gap apparatus - Google Patents

Abstract

The utility model discloses a discharge gap device, which is located on the ground wire insulator string, and the discharge gap device comprises a first fastener, a second fastener, a first fixing plate, a second fixing plate, The upper electrode and the lower electrode, the head end of the first fixing plate is fixed to the high voltage end of the ground wire insulator string through the first fastener, the end of the first fixing plate is connected to the head end of the upper electrode, and the end of the upper electrode is the arcing end, The head end of the second fixing plate is fixed to the low-voltage end of the ground wire insulator string through the second fastener. There are gaps. The beneficial effects of the utility model: the gap between the ground wire insulators is adjustable, and if the gap does not meet the performance requirements of the ground wire melting ice or lightning protection in actual engineering, it can be adjusted, and the operation is convenient.

Description

A discharge gap device

technical field

The utility model relates to a discharge gap device.

Background technique

The discharge gap is a gas discharge device commonly used in high-voltage technology. It is generally used to control the on-off of the high-voltage circuit. The air gap in the middle of the structure is used to discharge in advance to prevent various overvoltages (such as lightning, operation, etc.) from affecting the high-voltage sleeve. The protection of high-voltage equipment such as pipes is similar to lightning arresters and overvoltage protectors. The discharge gap usually consists of two electrodes, one connected to the high-voltage end and the other connected to the low-voltage end. The two electrodes are insulated. When the voltage between the two electrodes reaches the breakdown voltage, the insulation is broken down into conduction. state, after the freewheeling disappears, due to the self-recovery of the insulation, the two electrodes become insulated, and the circuit is disconnected again.

The transmission line is located in the wilderness and is vulnerable to lightning strikes. The direct lightning overvoltage caused by lightning strikes on the line and the induced lightning overvoltage caused by the lightning strike on the ground near the line are the so-called atmospheric overvoltages that often occur on transmission lines. The accidents caused by insulator flashover, line tripping and lightning wave invasion and damage to electrical equipment in substations account for a large part of the total accidents in the power grid.

Therefore, in order to solve the above problems, a new technical solution is provided.

Utility model content

The utility model provides a discharge gap device.

The technical scheme that the utility model adopts is:

A discharge gap device, the discharge gap device is located on the ground wire insulator string, the discharge gap device includes a first fastener, a second fastener, a first fixing plate, a second fixing plate, an upper electrode and a lower electrode , the head end of the first fixing plate is fixed to the high-voltage end of the ground wire insulator string through the first fastener, the end of the first fixing plate is connected to the head end of the upper electrode, and the end of the upper electrode is the arcing end, so The head end of the second fixing plate is fixed to the low-voltage end of the ground wire insulator string through the second fastener, the end of the second fixing plate is connected to the head end of the lower electrode, the end arc end of the lower electrode, and the arc end end There is a gap with the arc end.

The arc striking end is bent from bottom to top, and the arc striking end is bent from top to bottom.

The angle at which the arc striking end bends from bottom to top and the angle at which the arc striking end bends from top to bottom are both 30-45°.

The beneficial effects of the utility model are: the gap between the ground wire insulators is adjustable, and if the gap does not meet the performance requirements of the ground wire melting ice or lightning protection in actual engineering, it can be adjusted, and the operation is convenient;

It is an effective lightning protection device. It is installed at the end of the insulator string with a certain gap. It has a simple structure and is easy to maintain. It is used in conjunction with the automatic reclosing switch in the system. It can not only ground the lightning current in time, but also provide uninterrupted power supply to users. , so as to prevent flashover on the surface of the insulator, protect electrical equipment, and maintain the normal operation of the line;

Installing discharge gaps on the ground wire insulator strings, compared to insulating the lightning wires to the ground through small gaps, only the gaps break down when lightning strikes, and the lightning wires are grounded, which reduces the additional loss caused by the current in the lightning wires during normal operation of the line. , and the lightning protection line can also be used as a communication line;

When the gap is discharged, the arc is formed at the closest distance between the electrodes, and then the arc formed on the upper part of the horn-shaped gap is rapidly elongated. This kind of arc is generally easy to extinguish, and the electrode will be burned at the end of the horn gap due to the pull-up of the arc. There will be no burns at the place with the smallest gap distance, so as to ensure the correct action next time;

A small tip is added at the gap to increase the inhomogeneity of the gap electric field.

Description of drawings

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in further detail.

Fig. 1 is a schematic structural diagram of Example 1, wherein a is a hanging string fitting, and b is a tension string fitting.

Among them: 1. First fastener, 2. Second fastener, 3. First fixed plate, 4. Second fixed plate, 5. Upper electrode, 6. Lower electrode, 7. Ground insulator string, 8 , The arc end, 9, the arc end.

Detailed ways

In order to deepen the understanding of the utility model, the utility model will be further described below in conjunction with the embodiments and accompanying drawings. The embodiment is only used to explain the utility model, and does not constitute a limitation to the protection scope of the utility model.

Example 1

As shown in Figure 1, a discharge gap device of the present invention is located on the ground wire insulator string, and the discharge gap device includes a first fastener 1, a second fastener 2, and a first fixing plate 3 , the second fixed plate 4, the upper electrode 5 and the lower electrode 6, the head end of the first fixed plate 3 is fixed to the high voltage end of the ground wire insulator string 7 through the first fastener 1, and the end of the first fixed plate 3 is connected to the upper electrode 5, the end of the upper electrode 5 is the arcing end 8, the head end of the second fixed plate 4 is fixed to the low-voltage end of the ground wire insulator string 7 through the second fastener 2, and the end of the second fixed plate 4 is connected to the lower The head end of the electrode 6, the end arc end 9 of the lower electrode 6, there is a gap between the arc end 8 and the arc end 9, the arc end 8 is bent from bottom to top, and the arc end 9 is bent from top to bottom. The bending angle of end 8 from bottom to top and the angle of bending from top to bottom of arc starting end 9 are both 30-45°. When the gap discharges, the arc is formed at the place where the electrodes are closest to each other, and then the arc formed by the upper part of the double horn-shaped gap is drawn. Rapid elongation, this kind of arc is generally easy to extinguish, and it will also be pulled up by the arc, and the electrodes will be burned at the end of the horn gap, and the gap distance will be the smallest, so as to ensure the correct operation next time.

It is an effective lightning protection device. It is installed at the end of the insulator string with a certain gap. It has a simple structure and is easy to maintain. It is used in conjunction with the automatic reclosing switch in the system. It can not only ground the lightning current in time, but also provide uninterrupted power supply to users. , so as to prevent flashover on the surface of the insulator, protect electrical equipment, and maintain the normal operation of the line;

Installing discharge gaps on the ground wire insulator strings, compared to insulating the lightning wires to the ground through small gaps, only the gaps break down when lightning strikes, and the lightning wires are grounded, which reduces the additional loss caused by the current in the lightning wires during normal operation of the line. , and the lightning protection line can also be used as a communication line.

The electrical test requirements for the discharge gap of the utility model:

According to the function and design requirements of the discharge gap device, the following electrical type tests should be done.

(1) Lightning impulse voltage test or 50% full wave impulse flashover voltage test

This test is mainly to measure the electric strength of the discharge gap against lightning overvoltage. In order to protect the insulator, its electric strength must be less than the impact flashover voltage of the insulator string. Surface flashover.

According to the requirements of the IEC standard, the 1.2/50 standard shock waveform is used for lightning shock simulation. The commonly used impulse flashover voltage with a probability of 50% is its lightning dry withstand voltage. The test can be carried out by the insertion method or the lifting method. After the value is converted to the standard atmospheric state, it is generally 6 to 7 times the line phase voltage.

(2) Power frequency wet flashover voltage test

According to the requirements of IEC standards, the arithmetic mean value of the voltage causing power frequency flashover measured by applying standard artificial force on the gap can also be taken as the flashover voltage with a probability of 50%.

Its purpose is to assess the ability of the gap to withstand working voltage and operating overvoltage under line operating conditions. Its value is generally 4~4.5 times the phase voltage of the line.

(3) Power frequency wet withstand voltage

Operating experience shows that electrical equipment subjected to a one-minute AC withstand voltage test can generally guarantee safe operation. In the IEC standard, 75% of the predetermined test voltage is generally taken, and then a voltage level is increased at a speed of 2% of the test voltage per second, and the number can be taken after maintaining for one minute without flashover or breakdown. However, it can also be maintained at 95% of the power frequency wet flashover voltage for one minute. If flashover still occurs, it can be tolerated by dropping 2%.

(4) Radio interference test

The discharge gap is installed on the insulator string, which will inevitably increase its radio interference. According to the requirements of the 275kV insulator string in the Malaysian tender, it is less than 46db.

(5) Initial corona voltage test

Corona test requirements for discharge gaps are similar to other corona requirements for fittings with the same voltage level and same altitude.

The above are only preferred embodiments of the utility model, and are not intended to limit the utility model in any other form, and any modifications or equivalent changes made according to the technical essence of the utility model still belong to the utility model. Scope of protection claimed.

Claims (3)

1. A discharge gap device, characterized in that: the discharge gap device is located on the ground wire insulator string, and the discharge gap device includes a first fastener, a second fastener, a first fixing plate, and a second fixing plate , the upper electrode and the lower electrode, the head end of the first fixing plate is fixed to the high voltage end of the ground wire insulator string through the first fastener, the end of the first fixing plate is connected to the head end of the upper electrode, and the end of the upper electrode It is the arcing end, the head end of the second fixing plate is fixed to the low-voltage end of the ground wire insulator string through the second fastener, the end of the second fixing plate is connected to the head end of the lower electrode, and the end arcing end of the lower electrode , There is a gap between the arc striking end and the arc striking end. 2 . The discharge gap device according to claim 1 , wherein the arc striking end is bent from bottom to top, and the arc striking end is bent from top to bottom. 3 . 3. A discharge gap device according to claim 1, characterized in that: the angle at which the arc striking end bends from bottom to top and the angle at which the arc striking end bends from top to bottom are both 30-45°.