阅读说明：本技术 一种间隙强制触发装置及交流可控避雷器 (Clearance forced trigger device and alternating current controllable lightning arrester ) 是由 李国富 余辉 董勤晓 李志远 李会兵 刘赫 于 2020-12-24 设计创作，主要内容包括：本发明提供了一种间隙强制触发装置及交流可控避雷器。该装置包括：高电位端触发线圈、地电位端触发线圈、两个主电极和两个点火电极；其中,两个主电极之间具有主间隙,两个点火电极与两个主电极一一对应,并且,点火电极和对应的主电极之间具有点火间隙；高电位端触发线圈的两端分别与其中一个主电极、点火电极电连接,地电位端触发线圈的两端分别与另一个主电极、点火电极电连接。本发明利用可控避雷器自身作为触发能量源,通过高电位端触发线圈和地电位端触发线圈,当动作电流流过受控部分时产生电压触发脉冲,将输出电压引出至点火间隙处,在电压触发脉冲的作用下击穿点火间隙放电产生初始等离子体,击穿导通主间隙,使得受控部分短接。(The invention provides a gap forced triggering device and an alternating current controllable lightning arrester. The device includes: the high-potential end trigger coil, the ground-potential end trigger coil, two main electrodes and two ignition electrodes; the ignition device comprises two main electrodes, two ignition electrodes and a control circuit, wherein a main gap is formed between the two main electrodes, the two ignition electrodes correspond to the two main electrodes one to one, and an ignition gap is formed between the ignition electrodes and the corresponding main electrodes; two ends of the high-potential end trigger coil are respectively and electrically connected with one main electrode and the ignition electrode, and two ends of the ground-potential end trigger coil are respectively and electrically connected with the other main electrode and the ignition electrode. The controllable lightning arrester is used as a trigger energy source, and through the high-potential end trigger coil and the ground-potential end trigger coil, when an action current flows through a controlled part, a voltage trigger pulse is generated, an output voltage is led out to an ignition gap, the ignition gap is broken down under the action of the voltage trigger pulse to discharge to generate an initial plasma, and a main gap is broken down and conducted, so that the controlled part is in short circuit.)

1. A gap forcing trigger device, comprising: the high-potential end trigger coil, the ground-potential end trigger coil, two main electrodes and two ignition electrodes; wherein the content of the first and second substances,

the high-potential end triggering coil is used for being sleeved at a high-potential end of a controlled part of the alternating-current controllable lightning arrester so as to generate a voltage triggering pulse when the alternating-current controllable lightning arrester flows through action current;

the ground potential end trigger coil is used for being sleeved at the ground potential end of the controlled part of the alternating current controllable lightning arrester so as to generate voltage trigger pulse when the alternating current controllable lightning arrester flows through action current;

a main gap is formed between the two main electrodes, the two ignition electrodes correspond to the two main electrodes one by one, and an ignition gap is formed between each ignition electrode and the corresponding main electrode;

two ends of the high-potential end trigger coil are respectively and electrically connected with one main electrode and the ignition electrode corresponding to the main electrode, two ends of the ground-potential end trigger coil are respectively and electrically connected with the other main electrode and the ignition electrode corresponding to the main electrode, the main electrodes and the ignition electrodes corresponding to the main electrodes break down the ignition gap to discharge under the action of the voltage trigger pulse to generate initial plasma, so that the main gap breaks down and conducts, a controlled part of the lightning arrester body is further in short circuit, and overvoltage protection of the alternating-current controllable lightning arrester on a power system is realized.

2. The gap-forcing trigger device according to claim 1, wherein the high-potential side trigger coil and/or the ground-potential side trigger coil is a loop-shaped trigger coil.

3. The gap forcing trigger device of claim 2,

the cross-sectional area of the high potential side trigger coil and/or the ground potential side trigger coil is calculated by using the following formula:

in the formula: u shape_mThe pulse amplitude of the output voltage of the high potential end trigger coil and/or the ground potential end trigger coil is obtained; t is_mThe rise time of the voltage pulse of the high potential end trigger coil and/or the ground potential end trigger coil; n is the number of turns of the coil winding of the high potential end trigger coil and/or the ground potential end trigger coil; b is_sTriggering a coil for the high potential terminal and/or the magnetic core saturation magnetic induction intensity of the ground potential end trigger coil; k is a reliable coefficient, and k is more than or equal to 1 and less than or equal to 1.2.

4. The gap forcing trigger device of claim 2,

the annular inner diameter of the high-potential end trigger coil is larger than the maximum outer diameter of the high-potential end of the controlled part of the lightning arrester body; and/or the presence of a gas in the gas,

the annular inner diameter of the ground potential end trigger coil is larger than the maximum outer diameter of the high ground potential end of the controlled part of the lightning arrester body.

5. The gap forcing trigger device according to claim 2, wherein the high potential side trigger coil and/or the ground potential side trigger coil is a single layer wound coil.

6. A gap forcing trigger device according to any one of claims 1 to 5, further comprising:

and the supporting mechanism is used for supporting the two main electrodes.

7. The gap enforcement trigger of claim 6, wherein the support mechanism comprises:

a supporting seat;

an insulating support column disposed above the support base;

and the two insulating supports are arranged at the top ends of the insulating support columns, and an included angle is formed between the two insulating supports so as to support the two main electrodes respectively.

8. The gap forcing trigger device of claim 7,

the insulating bracket is provided with a supporting pipe for supporting the main electrode and enabling the connecting wire to pass through the supporting pipe; the connecting line is used for electrically connecting the main electrode and the high-potential end trigger coil or the ground-potential end trigger coil.

9. A gap forcing trigger device according to any one of claims 1 to 5,

the main electrode is provided with a jack, the ignition electrode is inserted in the jack, the high-potential end trigger coil and/or the ground potential end trigger coil are/is connected with the main electrode through a coaxial outer conductor, and the high-potential end trigger coil and/or the ground potential end trigger coil are/is connected with the ignition electrode through a coaxial inner conductor.

10. An alternating current controllable arrester, comprising: a lightning arrester body and a gap forcing trigger device according to any one of claims 1 to 9; wherein the content of the first and second substances,

the gap forcing triggering device is connected in parallel to the controlled part of the arrester body, a high-potential end triggering coil of the gap forcing triggering device is sleeved at the high-potential end of the controlled part of the arrester body, and a ground-potential end triggering coil of the gap forcing triggering device is sleeved at the ground-potential end of the controlled part of the arrester body.

Technical Field

The invention relates to the technical field of overvoltage protection of power systems, in particular to a gap forced triggering device and an alternating current controllable lightning arrester.

Background

In an ultra-high voltage and extra-high voltage power system, if the overvoltage level can be deeply reduced, the method is very favorable for the insulation matching design of the system and the reduction of the manufacturing difficulty of power transmission and transformation equipment. The controllable lightning arrester technology is a system overvoltage flexible limiting technology adaptive to the change of operating conditions.

Referring to fig. 1, a controllable arrester is composed of a fixed part and a controlled part where a controllable unit is connected in parallel. When the system normally operates, the controllable unit is in a disconnected state, and the arresters of the fixed part and the controlled part are both put into operation; when the overvoltage occurs in the system, the controllable unit is quickly conducted, and the controlled part is in short circuit, so that the volt-ampere characteristic of the lightning arrester is dynamically changed, and the overvoltage of the system is deeply reduced.

At present, a non-closed air gap (hereinafter referred to as a gap) is adopted as a controllable unit, and is an economic and reliable implementation means of a controllable lightning arrester for an alternating current power system. Further, such gaps can be divided into two types: the forced trigger type and the self-discharge type have the following main technical conditions: 1. the system needs to endure normal operation voltage of the system, 2, the system needs to be reliably conducted under overvoltage of the system, and 3, the power frequency follow current electric arc needs to be cut off after the overvoltage is finished. For the self-discharge type gap, the gap adjustment is difficult, and it is very difficult to satisfy the above three technical conditions at the same time. For the forced triggering type, the gap forced discharge is triggered by an external triggering energy source, and the use is inconvenient due to the complexity of an energy supply system.

Disclosure of Invention

In view of this, the invention provides a gap forced triggering device and an alternating current controllable lightning arrester, and aims to solve the problems that a self-discharge type gap is difficult to meet technical conditions, and a forced triggering type gap triggers an energy supply system through an external triggering energy source to be complex.

In one aspect, the present invention provides a gap forcing trigger device, including: the high-potential end trigger coil, the ground-potential end trigger coil, two main electrodes and two ignition electrodes; the high-potential end triggering coil is used for being sleeved at a high-potential end of a controlled part of the alternating-current controllable lightning arrester so as to generate a voltage triggering pulse when the alternating-current controllable lightning arrester flows through action current; the ground potential end trigger coil is used for being sleeved at the ground potential end of the controlled part of the alternating current controllable lightning arrester so as to generate voltage trigger pulse when the alternating current controllable lightning arrester flows through action current; a main gap is formed between the two main electrodes, the two ignition electrodes correspond to the two main electrodes one by one, and an ignition gap is formed between each ignition electrode and the corresponding main electrode; two ends of the high-potential end trigger coil are respectively and electrically connected with one main electrode and the ignition electrode corresponding to the main electrode, two ends of the ground-potential end trigger coil are respectively and electrically connected with the other main electrode and the ignition electrode corresponding to the main electrode, the main electrodes and the ignition electrodes corresponding to the main electrodes break down the ignition gap to discharge under the action of the voltage trigger pulse to generate initial plasma, so that the main gap breaks down and conducts, a controlled part of the lightning arrester body is further in short circuit, and overvoltage protection of the alternating-current controllable lightning arrester on a power system is realized.

Further, in the gap forced triggering device, the high-potential terminal triggering coil and/or the ground-potential terminal triggering coil is a ring-shaped triggering coil.

Further, in the gap forced triggering device, the cross-sectional area of the high-potential side trigger coil and/or the ground-potential side trigger coil is calculated by using the following formula:

in the formula: u shape_mTriggering the coil and/or for the high potential sideThe output voltage pulse amplitude of the ground potential end trigger coil; t is_mThe rise time of the voltage pulse of the high potential end trigger coil and/or the ground potential end trigger coil; n is the number of turns of the coil winding of the high potential end trigger coil and/or the ground potential end trigger coil; b is_sMagnetic core saturation magnetic induction intensity of the high potential end trigger coil and/or the ground potential end trigger coil; k is a reliable coefficient, and k is more than or equal to 1 and less than or equal to 1.2.

Further, in the gap forced triggering device, the annular inner diameter of the high-potential end triggering coil is larger than the maximum outer diameter of the high-potential end of the controlled part of the lightning arrester body; and/or the annular inner diameter of the ground potential end triggering coil is larger than the maximum outer diameter of the high ground potential end of the controlled part of the lightning arrester body.

Further, in the gap forced triggering device, the high-potential end triggering coil and/or the ground-potential end triggering coil is a single-layer wound coil.

Further, the gap forced triggering device further includes: and the supporting mechanism is used for supporting the two main electrodes.

Further, in the gap forced triggering apparatus, the supporting mechanism includes: a supporting seat; an insulating support column disposed above the support base; and the two insulating supports are arranged at the top ends of the insulating support columns, and an included angle is formed between the two insulating supports so as to support the two main electrodes respectively.

Furthermore, in the gap forced triggering device, a support tube is arranged on the insulating support to support the main electrode and enable the connecting wire to pass through the support tube; the connecting line is used for electrically connecting the main electrode and the high-potential end trigger coil or the ground-potential end trigger coil.

Further, in the gap forced triggering device, a plug hole is formed in the main electrode, the ignition electrode is inserted into the plug hole, the high-potential end triggering coil and/or the ground-potential end triggering coil are/is connected with the main electrode through an outer conductor of a coaxial line, and the high-potential end triggering coil and/or the ground-potential end triggering coil are/is connected with the ignition electrode through an inner conductor of a coaxial line.

In another aspect, the present invention further provides an ac controllable lightning arrester, including: the lightning arrester body and the gap forced triggering device; the gap forcing trigger device is connected in parallel to the controlled part of the arrester body, a high-potential end trigger coil of the gap forcing trigger device is sleeved at the high-potential end of the controlled part of the arrester body, and a ground-potential end trigger coil of the gap forcing trigger device is sleeved at the ground-potential end of the controlled part of the arrester body.

The gap forced trigger device and the alternating current controllable lightning arrester provided by the invention can generate voltage trigger pulse with higher amplitude when the action current of the lightning arrester body flows through the controlled part through the high-potential end trigger coil sleeved on the high-potential end of the controlled part of the alternating current controllable lightning arrester and the ground-potential end trigger coil sleeved on the ground-potential end of the controlled part of the alternating current controllable lightning arrester, and lead the output voltage to the ignition gap between the ignition electrode and the main electrode, so that the ignition electrode breaks down the ignition gap to discharge under the action of the voltage trigger pulse to generate initial plasma, so that the main gap breaks down and conducts, the controlled part of the lightning arrester body is in short circuit, and the overvoltage protection of the alternating current controllable lightning arrester on a power system is realized. The device does not need any external power supply, only utilizes the controllable lightning arrester as a trigger energy source of the forced trigger type gap to work and obtain energy, solves the problem that the forced trigger type gap needs external energy distribution as a controllable unit, and can also send trigger pulse to the ignition gap when overvoltage occurs to the system, so that the main gap is forced to be triggered and conducted, and the gap forced trigger function is realized.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

fig. 1 is a schematic structural diagram of a controllable lightning arrester in the prior art;

fig. 2 is a schematic structural diagram of an ac controllable lightning arrester according to an embodiment of the present invention;

fig. 3 is a schematic circuit diagram of an ac controllable lightning arrester according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a high-potential end trigger coil and/or a ground-potential end trigger coil provided in an embodiment of the present invention;

fig. 5 is a waveform diagram of an output voltage pulse generated by the high-potential-end trigger coil and/or the ground-potential-end trigger coil according to the embodiment of the invention.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

Referring to fig. 2 to 3, preferred structures of the ac controllable lightning arrester provided by the embodiment of the invention are shown. As shown in the figure, the ac controllable arrester includes: the lightning arrester comprises a lightning arrester body 1 and a gap forced triggering device 2; the lightning arrester comprises a lightning arrester body 1 and a control part 12, wherein the gap forced triggering device 2 is connected in parallel with the control part 12 to serve as a controllable part, so that when the system normally operates, the gap forced triggering device 2 is in a disconnection state, and the lightning arrester body is put into operation; when the overvoltage occurs in the system, the gap forces the trigger device 2 to be quickly conducted, and the controlled part 12 is in short circuit, so that the volt-ampere characteristic of the lightning arrester body is dynamically changed, and the overvoltage of the system is deeply reduced.

With continued reference to fig. 2 to 3, the gap forcing trigger 2 includes: a high-potential end trigger coil 21, a ground-potential end trigger coil 22, two main electrodes 23, two ignition electrodes 24, and a support mechanism 25; wherein the content of the first and second substances,

the high potential end trigger coil 21 is used for being sleeved at a high potential end of a controlled part of the alternating current controllable lightning arrester so as to generate a voltage trigger pulse when the alternating current controllable lightning arrester flows through action current; the ground potential terminal trigger coil 22 is adapted to be connected to the ground potential terminal of the controlled portion of the ac controllable arrester for generating a voltage trigger pulse when the ac controllable arrester passes through the action current. Specifically, the high potential side trigger coil 21 may be sleeved at the high potential side of the controlled part 12, that is, near the end (top end as shown in fig. 2) connected to the high voltage bus, and the high potential side trigger coil 21 may be sleeved at the flange of the high potential side of the controlled part 12 to connect and fix the high potential side trigger coil 21; the ground potential end trigger coil 22 can be sleeved at a ground potential end of the controlled part 12, namely, an end part (a bottom end as shown in fig. 2) close to a ground wire, and the ground potential end trigger coil 22 can be sleeved at a flange plate at a low potential end of the controlled part 12 to realize connection and fixation of the ground potential end trigger coil 22; when the operating current i of the arrester body 1 flows through the controlled portion 12, that is, the operating current i flows through the high-potential-end trigger coil 21 and the ground-potential-end trigger coil 22, since the outputs of the high-potential-end trigger coil 21 and the ground-potential-end trigger coil 22 are approximately no-load, a voltage trigger pulse with a relatively high amplitude is generated at the output ends of the high-potential-end trigger coil 21 and the ground-potential-end trigger coil 22. In FIG. 3, TC₁The high potential end triggers the coil 21, TC₂The coil 22 is triggered at ground potential.

A main gap 26 is provided between two main electrodes 23, two ignition electrodes 24 are in one-to-one correspondence with the two main electrodes 23, an ignition gap (not shown in the figure) is provided between the ignition electrode 24 and the corresponding main electrode 23, two ends of the high-potential end trigger coil 21 are respectively and electrically connected with one main electrode 23 (such as the left main electrode shown in fig. 2) and the ignition electrode 24 corresponding to the main electrode 23, two ends of the ground-potential end trigger coil 22 are respectively and electrically connected with the other main electrode 23 (such as the right main electrode shown in fig. 2) and the ignition electrode 24 corresponding to the main electrode 23, the main electrode 23 and the corresponding ignition electrode 24 break through the ignition gap under the action of a voltage trigger pulse to discharge to generate initial plasma, so that the main gap 26 is conducted, and further, a controlled part of the lightning arrester body is shorted, and overvoltage protection of the ac controllable lightning arrester to, namely, the high-potential end trigger coil 21 and the ground-potential end trigger coil 22 generate pulse high voltages, which act on the corresponding ignition electrodes 24 respectively, the ignition electrodes 24 discharge the pulses, the electric field of the main gap 26 between the two main electrodes 23 is distorted due to the discharge of the ignition electrodes 24, so that the breakdown voltage of the main gap 26 is greatly reduced, and finally the main gap 26 breaks down, so that the two main electrodes 23 are conducted, and further a communication line is formed among the high-potential end trigger coil 21, the main electrodes 23, the main gap 26, the main electrodes 23 and the ground-potential end trigger coil 22, so as to short-circuit the controlled part 12, and realize the gap forced trigger function, thereby dynamically changing the characteristics of the lightning arrester, and playing a role of deeply reducing the overvoltage and volt-ampere of the system. In order to support and fix the ignition electrode 24, the main electrode 23 may be provided with a plug hole (not shown), and the ignition electrode 24 may be inserted into the plug hole and may be supported by an insulating member, so that an ignition gap is formed between the ignition electrode 24 and the main electrode 23; the high potential end trigger coil 21 and/or the ground potential end trigger coil 22 are connected with the main electrode 23 through a coaxial outer conductor, and the high potential end trigger coil 21 and/or the ground potential end trigger coil 22 are connected with the ignition electrode 24 through a coaxial inner conductor, so that a voltage trigger pulse with higher amplitude generated by the high potential end trigger coil 21 and/or the ground potential end trigger coil 22 is output to the main electrode 23 and the ignition electrode 24, and further breakdown conduction of the main gap 26 is realized through the ignition electrode 24; of course, the high-potential end trigger coil 21 and/or the ground-potential end trigger coil 22 may be electrically connected to the main electrode 23 and the ignition electrode 24 in other manners, which is not limited in this embodiment.

The supporting mechanism 25 is used to support the two main electrodes 23, so that a main gap 26 is formed between the two main electrodes 23. Specifically, the support mechanism 25 functions as a support to support the main electrode 23. The ignition electrode 24 is supported and fixed in the socket of the main electrode 23 by an insulating member to achieve discharge triggering.

With continued reference to fig. 2, the support mechanism 25 includes: a support seat 251, an insulating support 252 and two insulating supports 253; wherein the insulating support 252 is disposed above the support base 251 (relative to the position shown in fig. 2); the two insulating supports 253 are disposed at the top end of the insulating support 252, and the two insulating supports 253 are disposed at an included angle to support the two main electrodes 23 respectively. Specifically, the supporting seat 251 may be a supporting plate or other structure, and may be clamped on the ground or a working surface; the insulating support 252 may be an insulator, which is vertically disposed at a middle position of the support base 252; the two insulating supports 253 can also be insulators, and the bottom ends thereof can be connected to the top ends of the insulating pillars 252, and the top ends thereof serve as supporting ends for supporting the main electrodes 23. In order to support the main electrode 23, preferably, the insulating support 253 is provided with a support tube 254 for supporting the main electrode 23, and a connecting wire, such as a coaxial wire, is inserted through the support tube 254; the connecting wire is used for electrically connecting the main electrode 23 with the high-potential end trigger coil 21 or the ground-potential end trigger coil 22 so as to avoid the disorder of the circuit on the device; it is further preferred that the support tube 254 is slidably coupled to the top end of the insulating bracket 253 to adjust the distance of the main gap 26 between the two main electrodes 23.

With continued reference to fig. 2 and 4, in order to facilitate voltage triggering of the high-potential-side trigger coil 21 and the ground-potential-side trigger coil 22, it is preferable that the high-potential-side trigger coil 21 and/or the ground-potential-side trigger coil 22 be annular trigger coils so as to be sleeved on the high-potential side and the ground potential side of the controlled portion 12, respectively. Further preferably, the annular inner diameter of the high-potential-end trigger coil 21 is larger than the maximum outer diameter of the high-potential end of the controlled portion of the arrester body; and/or the annular inner diameter of the ground potential end trigger coil 22 is larger than the maximum outer diameter of the high ground potential end of the controlled part of the lightning arrester body, so that the sleeve mounting requirements of the high ground potential end trigger coil 21 and the ground potential end trigger coil 22 are met. The high-potential end trigger coil 21 and/or the ground-potential end trigger coil 22 are single-layer wound coils, that is, the coil windings are wound in a single layer, so as to eliminate an interlayer capacitance effect caused by multilayer winding, and the capacitance effect can reduce the amplitude of the output voltage pulse.

In the present embodiment, the cross-sectional area of the high-potential-side trigger coil 21 and/or the ground-potential-side trigger coil 22 is calculated using the following formula:

in the formula: u shape_mThe pulse amplitude of the output voltage of the high-potential end trigger coil 21 and/or the ground-potential end trigger coil 22; t is_mThe rise time of the voltage pulse for the high-potential-end trigger coil 21 and/or the ground-potential-end trigger coil 22; n is the number of coil winding turns of the high-potential-end trigger coil 21 and/or the ground-potential-end trigger coil 22; b is_sMagnetic core saturation magnetic induction intensity of the high potential end trigger coil 21 and/or the ground potential end trigger coil 22; k is a reliable coefficient, and k is more than or equal to 1 and less than or equal to 1.2.

In this embodiment, the main electrode 23 may be a hemispherical electrode, and the electric field distribution thereof is uniform, and the discharge voltage is stable.

The following describes the gap forcing trigger device provided in the embodiment of the present invention in more detail.

As shown in fig. 2 to 4, the gap forced triggering apparatus includes: a high-potential end trigger coil 21, a ground-potential end trigger coil 22, two main electrodes 23, two ignition electrodes 24, and a support mechanism 25; the high-potential end trigger coil 21 and the ground potential end trigger coil 22 are respectively sleeved on a flange plate at the high-potential end of the controlled part 12 of the lightning arrester body and a flange plate at the high-ground potential end of the controlled part 12 of the lightning arrester body; one end of the high potential end trigger coil 21 is connected with a main electrode 23 through a coaxial outer conductor, and the output end of the high potential end trigger coil 21 is connected with an ignition electrode 24 arranged in the main electrode 23 through a coaxial inner conductor, namely a core wire; one end of the ground potential terminal trigger coil 22 is connected to the main electrode 23 through an outer conductor of the coaxial line, and the output end of the ground potential terminal trigger coil 22 is connected to the inner conductor of the coaxial line

An ignition electrode 24 provided in the main electrode 23; the annular inner diameters Di of the high-potential end trigger coil 21 and the ground-potential end trigger coil 22 are 250 mm; the coil winding adopts single-layer winding, and the number of turns N is 1000; the magnetic core is made of nanocrystalline material and has saturation magnetic induction intensity B_sIs taken as B_s1.1T; when the output voltage pulse amplitude U_mIs taken as U_m3.5 kV; rise time T of voltage pulse_mTaking Tm as 100us, and taking the reliability coefficient k as 1;

the annular section S of the coil is calculated according to the formula and is more than or equal to 203mm²And S is 225mm². According to the test, the trigger voltage pulse waveforms generated at the output ends of the trigger coils TC1 and TC2, i.e. the high-potential-end trigger coil 21 and the ground-potential-end trigger coil 22, are as shown in fig. 5, and under the action of the voltage trigger pulse, the ignition gap with the distance of 2mm can be punctured, and the generated initial plasma can cause the main gap to be forcibly triggered to conduct.

In summary, according to the gap forcing trigger device and the ac controllable lightning arrester provided by this embodiment, the high-potential end trigger coil 21 connected to the high-potential end of the controlled portion of the ac controllable lightning arrester in a sleeved manner and the ground-potential end trigger coil 22 connected to the ground-potential end of the controlled portion of the ac controllable lightning arrester in a sleeved manner can generate a voltage trigger pulse with a higher amplitude when the action current i of the lightning arrester body 1 flows through the controlled portion 12, and an output voltage is led out to the ignition gap between the ignition electrode 24 and the main electrode 23, so that the ignition electrode 24 breaks through the ignition gap under the action of the voltage trigger pulse to generate an initial plasma, so as to break through the main gap 26, short-circuit the controlled portion of the lightning arrester body, and implement overvoltage protection of the ac controllable lightning arrester on the power system. The device does not need any external power supply, only utilizes the controllable lightning arrester as a trigger energy source of the forced trigger type gap to work and obtain energy, solves the problem that the forced trigger type gap needs external energy distribution as a controllable unit, and can also send trigger pulse to the ignition gap when overvoltage occurs to the system, so that the main gap is forced to be triggered and conducted, and the gap forced trigger function is realized.

It should be noted that in the description of the present invention, the terms of direction or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, which are only for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

Furthermore, it should be noted that, in the description of the present invention, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.