An intelligent multi-layer gap overvoltage protector based on copper-chromium alloy material with high solderability

Abstract

The present invention discloses an intelligent multi-layer gap overvoltage protector based on a copper-chromium alloy material. A multi-layer discharge gap composed of multiple electrodes made of the copper-chromium alloy material is installed in an insulating housing. Each electrode is insulated and isolated by an insulating medium. A trigger electrode is designed at the bottom electrode gap of the multi-layer gap. The trigger electrode can automatically sense and couple to receive the energy of a lightning overvoltage, and trigger the bottom electrode gap of the multi-layer gap and other gaps to conduct quickly. Therefore, the three-terminal overvoltage protection gap of this intelligent multi-layer gap structure has remarkable characteristics such as a high DC breakdown voltage, a high voltage protection level, a fast response time, and a strong ability to resist power frequency or DC follow-up current. This intelligent multi-layer gap overvoltage protector can be used for the protection of direct lightning strikes and lightning-induced overvoltages in application scenarios such as the communication field and even the power field.

Description

Technical Field

[0001] The present invention relates to an overvoltage protection device, and particularly to an intelligent multi-layer gap overvoltage protector based on a copper-chromium alloy material and having high solderability for use in the power field and the communication field. Background Art

[0002] With the application of switching equipment in high-voltage transmission lines and the technological progress of electronic and information systems, the impact and harm of overvoltage on sensitive electronic devices and communication devices with weak immunity are increasing day by day. Overvoltage protection is an important guarantee for the safe operation of power and communication systems.

[0003] Since the advent of the overvoltage protection spark gap with a horn electrode structure from Phoenix Contact GmbH in Germany and the overvoltage protection product with a laminated graphite structure from Oberschleissheim GmbH, many domestic research institutions and production enterprises have adopted the overvoltage protection gap with this main structure based on the advantages of no arc leakage and strong subsequent current suppression ability of the laminated structure overvoltage protection gap. In terms of the peripheral voltage equalizing circuit, failure indication, etc., many overvoltage protection gaps with specific functions have been invented, such as: ZL 02107856.4, a spark gap device for carrying lightning current; ZL 200710049004.9, a high-efficiency laminated graphite discharge gap device, etc.

[0004] The overvoltage protection gap with a laminated graphite structure has solved to a certain extent the technical problem of poor subsequent current suppression ability of a single gap (such as a horn gap), but has the following defects:

[0005] First, for the lead electrode of the overvoltage protection gap with a laminated graphite structure, due to the unreliable electrical connection between the lead metal electrode and the graphite electrode, the contact resistance between the lead electrode and the graphite electrode is large. When lightning current flows through, the contact is prone to failure due to overheating, seriously affecting the stable reliability and service life of the overvoltage protection gap.

[0006] Second, in order to improve the ability of the laminated graphite gap to resist subsequent power frequency follow current, it is often achieved by increasing the number of gaps in the laminated graphite gap. As a result, while increasing the reliability under normal operation and improving the ability to resist subsequent power frequency follow current, the impact breakdown voltage of the laminated graphite gap is increased, and the overvoltage protection level is correspondingly reduced. That is to say, the technical problem of mutual restriction between the ability of the gap type overvoltage protector to resist subsequent power frequency and voltage protection has not been effectively solved. Summary of the Invention

[0007] The object of the present invention is to propose an intelligent multi-layer gap overvoltage protector with high weldability based on a copper-chromium alloy material in view of the defects existing in the existing laminated graphite gaps, significantly improving the protection performance of the multi-layer overvoltage protection gaps, effectively solving the technical problem of the mutual restriction of the AC and DC voltage withstand capabilities, the anti-continuous current capability and the voltage protection level of the overvoltage protection gaps, and at the same time, significantly improving the weldability between the graphite multi-layer gaps and the external metal electrodes, thus solving the well-known defect of poor working reliability of the overvoltage protection gaps.

[0008] To achieve the above object, the present invention adopts the following technical solution:

[0009] An intelligent multi-layer gap overvoltage protector with high weldability based on a copper-chromium alloy material is composed of a multi-layer discharge gap formed by a plurality of copper-chromium alloy electrodes arranged in an insulating housing in series. An automatic overvoltage energy coupling trigger mechanism is connected between the upper lead electrode, the lower lead electrode and the trigger electrode arranged in the multi-layer discharge gap. By using the high weldability of the copper-chromium alloy and the automatic overvoltage energy coupling trigger mechanism to output a trigger pulse to the trigger electrode, a trigger discharge is preferentially formed between the trigger electrode and the lower lead electrode, thereby triggering the rapid conduction of each layer of discharge gap of the multi-layer gap overvoltage protector.

[0010] Furthermore, n pairs of discharge gaps composed of a plurality of copper-chromium alloy electrodes arranged in the insulating housing are insulated and isolated between adjacent two electrodes by an insulating dielectric material and then connected in series through an insulating connecting rod penetrating through each electrode and the insulating dielectric material. The insulating dielectric material is of an annular structure, and its outer contour is the same as the outer shape of the electrode;

[0011] The uppermost and lowermost electrodes of the multi-layer discharge gap are respectively led out of the insulating housing as the upper lead electrode and the lower lead electrode. The lead electrodes are welded on the copper-chromium alloy electrodes. A trigger electrode is arranged between the nth discharge gaps and led out of the insulating housing. The trigger electrode is insulated from the upper electrode and the lower of the nth discharge gap by an insulating dielectric. The trigger electrode is of an annular structure, and its outer contour is the same as the outer shape of each electrode of the discharge gap;

[0012] The automatic overvoltage energy coupling trigger mechanism is connected between the upper lead electrode, the lower lead electrode and the trigger electrode.

[0013] Furthermore, the automatic overvoltage energy coupling trigger mechanism is composed of a series-connected upper coupling capacitor, a lower coupling capacitor and an isolation gap connected between the upper coupling capacitor and the lower coupling capacitor. The two input ends of the automatic overvoltage energy coupling trigger mechanism are respectively connected to the upper lead electrode and the lower lead electrode, and the output end is connected between the trigger electrode and the lower lead electrode.

[0014] Furthermore, the copper-chromium alloy electrode is a sheet electrode cut from a round bar or a rectangular bar. The copper-chromium alloy electrode is circular, square or oval, and its structural dimensions can be in the range of 20 mm - 60 mm or even larger. A circular or square hole can be opened in the center of the copper-chromium alloy electrode, and the size range of the opening can be 3 - 5 mm or other values.

[0015] Furthermore, the gap between two adjacent copper-chromium alloy electrodes is 0.2 - 1.5 mm. The distance between two adjacent electrodes can be equidistant or non-equidistant. The thickness of the insulating dielectric material between each copper-chromium alloy electrode corresponds to the gap distance between the electrodes. The width of the insulating dielectric material ring is 5 - 10 mm, and a horizontal ring groove with a depth of 1.5 - 3 mm is opened on the inner side of the insulating dielectric.

[0016] Furthermore, the trigger electrode material is graphite material, copper or aluminum-zinc alloy.

[0017] Furthermore, the insulating dielectric between the trigger electrode and the upper and lower electrodes of the nth discharge gap is ceramic.

[0018] Furthermore, the width of the insulating dielectric ring between the trigger electrode and the upper and lower electrodes of the nth discharge gap is 1 / 4 to 1 / 3 of the width of the electrode size of each discharge gap.

[0019] The intelligent multi-layer gap overvoltage protector based on copper-chromium alloy material with high weldability of the present invention. The multi-layer overvoltage protection gap is composed of multiple electrodes. The adjacent two electrodes are insulated and isolated by an insulating dielectric material, and the height of the insulating dielectric isolation matches the gap distance between the adjacent electrodes of the multi-layer gap overvoltage protector. The engineered multi-layer structure overvoltage protection gap is made of copper-chromium alloy with good electrical conductivity, thermal conductivity, high hardness, wear resistance, explosion resistance, machinability and weldability, which completely solves the serious defect that the current graphite multi-layer gap overvoltage protector has poor weldability of the lead electrodes, resulting in unreliable performance or even failure and causing lightning strike accidents.

[0020] The design concept of the present invention is to reduce the number of discharge gaps of the multi-layer overvoltage protector, increase the distance Dgn of the nth gap, and add a trigger electrode and an automatic overvoltage energy coupling trigger mechanism between the upper and lower electrodes of the nth gap. When a lightning overvoltage occurs, the trigger electrode can automatically sense and couple the energy of the lightning overvoltage, output a trigger pulse to the trigger electrode, causing a trigger discharge to preferentially form between the trigger electrode and the lower lead-out electrode, quickly breaking down the nth discharge gap, and then triggering the rapid breakdown of other discharge gaps of the multi-layer gap overvoltage protector. It effectively solves the problem of the mutual restriction between the power frequency withstand voltage, the anti-continuous current ability, the lightning impulse voltage protection level, and the response time of the multi-layer gap overvoltage protector, making the overvoltage protection gap with a multi-layer structure have significant characteristics such as a high DC breakdown voltage, a high voltage protection level, a fast response time, and a strong ability to withstand power frequency or DC follow-up currents.

[0021] The distance between adjacent two electrodes can be equidistant or non-equidistant. The thickness of the insulating dielectric material between each copper-chromium alloy electrode is the same as the gap distance between the electrodes. The width of the insulating dielectric material ring is 5-10 mm, and a horizontal ring groove with a depth of 1.5-3 mm is provided at the middle height part inside the dielectric. Especially when the gap distance between adjacent two electrodes is relatively large, it can prevent the pollution of the inside of the insulating dielectric by metal vapor when the overvoltage protection gap passes through a large current.

[0022] The width of the insulating dielectric ring between the trigger electrode and between the trigger electrode and the upper and lower electrodes of the nth discharge gap is 1 / 4 to 1 / 3 of the width of the electrode size of each discharge gap, and at the position where the trigger electrode is located, the gap distance between the upper and lower electrodes of the discharge gap can be significantly larger than the gap distance between other electrodes.

[0023] The structural design of using copper-chromium alloy electrodes and an automatic overvoltage energy coupling trigger mechanism enables the intelligent multi-layer gap overvoltage protector with high current-carrying capacity and weldability to be used for the protection of direct lightning strikes and lightning induction overvoltages in application scenarios such as the communication field and even the power field.

[0024] Using copper-chromium alloy has better weldability than the existing all-graphite electrodes, and more effectively avoids the defect of the decline in protection performance caused by unreliable electrical contact. Brief Description of the Drawings

[0025] Figure 1a is a schematic diagram of the copper-chromium alloy material structure of the present invention;

[0026] Figure 1b is a schematic diagram of the rectangular cross-section of the copper-chromium alloy material;

[0027] Figure 1c is a schematic diagram of the circular cross-section of the copper-chromium alloy material;

[0028] Figure 2 is a schematic structural diagram of a discharge gap in the present invention;

[0029] Figure 3 is a schematic structural diagram of a multi-layer gap overvoltage protector based on a copper-chromium alloy material in the present invention;

[0030] In the figure: 1 - upper lead electrode; 2 - lower lead electrode; 3 - trigger electrode; 4 - insulating housing; 5 - insulating connecting rod. Specific embodiments

[0031] The present invention will be further described in detail below in conjunction with specific embodiments, but it is not intended to limit the present invention.

[0032] Referring to FIG. 1, the copper-chromium alloy material of the multi-layer gap overvoltage protection gap of the present invention. Among them, as Figure 1a the copper-chromium alloy bar can be a round bar or a rectangular or square bar, and the rectangular cross-section and circular cross-section of the copper-chromium alloy material are respectively as Figure 1b and Figure 1c shown.

[0033] Referring to Figure 2 and Figure 3 , the intelligent multi-layer gap overvoltage protector is composed of a series connection of multiple gaps formed by multiple electrodes. Figure 2 is the uppermost discharge gap of the multi-layer gap overvoltage protector of the present application. The gap distances between adjacent electrodes are Dg1, Dg2,..., Dgn respectively, and their values can be controlled between 0.5 - 1.5 mm; the adjacent two electrodes are insulated from each other by insulating media I1, I2,..., In respectively, where the heights of the insulating isolations I1, I2,..., In are Hg1, Hg2,..., Hgn, which match the gap distances between the adjacent two electrodes. A circular hole with a diameter of 3 - 5 mm can be opened at the centers of the multiple electrodes of the multi-layer overvoltage protection gap, which can facilitate the movement of conduction carriers between different gaps and improve the protection performance of the overvoltage protection gap; the shape of the insulating media isolation is a circular, square or oval structure with a middle hole, which is adapted to the circular, square or oval structure of the electrode.

[0034] Referring to Figure 3, a multi-layer gap overvoltage protector based on a copper-chromium alloy material with high solderability, is insulated and isolated between adjacent two electrodes by an insulating dielectric material and then connected in series through an insulating link 5 penetrating each electrode and the insulating dielectric material. The discharge gaps G1, ……, Gn, multiple electrodes, insulating isolations I1, I2, ……, In, etc. are installed in an insulating housing 4. Discharge gaps G1 (the upper and lower electrodes E of the first gap 1u , E 1d ), ……, Gn (the upper and lower electrodes E of the nth gap nu , E nd ) are formed in sequence. Their gap distances are Dg1, ……, Dgn respectively. Electrical insulation between adjacent two electrodes is achieved through insulating isolations I1, ……, In, and the heights of the insulating isolations are Hg1, ……, Hgn respectively. For simplicity, the lower electrode of adjacent two discharge gaps and the upper electrode of the following gap can be shared.

[0035] To solve the problem of mutual restriction between the power frequency withstand voltage and the lightning voltage protection level under normal operating conditions of the multi-layer gap, based on the passive multi-layer gap overvoltage protector, the present invention reduces the number of discharge gaps of the passive multi-layer overvoltage protector (for example, the number of discharge gaps can be reduced from 10 to 6) and adds a trigger electrode and an automatic overvoltage energy coupling trigger mechanism between the upper and lower two electrodes of the nth gap.

[0036] The electrode material of the trigger electrode can be selected from graphite material or metal or alloy (such as copper, aluminum-zinc alloy) material. The trigger electrode is insulated and isolated from the upper electrode E of the nth gap nu , lower electrode E nd by an insulating dielectric. The insulating dielectric material can be the same as the insulating dielectric isolation material between other electrodes, or a high dielectric constant dielectric material with strong release ability such as ceramic can be selected.

[0037] The structure and main working characteristics of the trigger electrode include the following aspects:

[0038] The nth gap distance Dgn can be 2-4 times or more than that of other gap distances. An intelligent trigger electrode is added in this gap. The intelligent trigger electrode is insulated and separated from the upper electrode E of the nth gap nu , lower electrode E nd by an insulating dielectric. Among them, the distance between the trigger electrode and the lower electrode E of the nth gap nd , that is, the height of the insulating dielectric, can be controlled within 1-1.5 mm, and the distance between the trigger electrode and the upper electrode E of the nth gap nu , that is, the height of the insulating dielectric, is greater than that from the lower electrode E ndThe distance therebetween can be controlled within 2 - 3 mm; the intelligent trigger electrode and the upper electrode E on the nth gap nu , the lower electrode E nd The shape of the insulating dielectric isolation structure between them is the same as that of the main electrode, and the ring width of the trigger electrode and the insulating dielectric isolation structure can be controlled within the range of 1 / 4 to 1 / 3 of the main electrode size.

[0039] The automatic overvoltage energy coupling trigger mechanism can be composed of an upper coupling capacitor, a lower coupling capacitor and an isolation gap, and the automatic overvoltage coupling trigger mechanism is connected in parallel with the multi-layer overvoltage protection gap..

[0040] Specifically: the two input ends of the automatic overvoltage energy coupling trigger mechanism are respectively connected to the upper lead-out electrode 1 and the lower lead-out electrode 2 of the multi-layer gap overvoltage protector, and the output end of the automatic overvoltage energy coupling trigger mechanism is electrically connected between the trigger electrode and the lower lead-out electrode 2. When a lightning overvoltage occurs, the automatic overvoltage energy coupling trigger mechanism automatically couples the overvoltage signal and generates a trigger high-voltage pulse on the lower capacitor of the automatic overvoltage mechanism, and the isolation gap of the automatic overvoltage energy coupling trigger mechanism quickly breaks down and conducts, resulting in a flashover discharge breakdown between the trigger electrode of the multi-layer overvoltage protector and the lower electrode E of the nth gap nd to generate initial trigger carriers, enabling the nth electrode of the multi-layer gap overvoltage protector to conduct quickly, so that the 1st to n - 1th gaps break down and conduct due to overvoltage, completing a lightning overvoltage protection process.

[0041] The present invention has been described in detail with reference to the above embodiments. Those of ordinary skill in the art should understand that: modifications or equivalent substitutions can still be made to the specific implementation manners of the present invention, and any modification or equivalent substitution that does not depart from the spirit and scope of the present invention shall be covered by the scope of the present patent claims.

Claims

1. An intelligent multi-layer gap overvoltage protector based on a copper-chromium alloy material with high solderability, Characterized in that: It is formed by connecting in series multiple multi-layer discharge gaps composed of copper-chromium alloy electrodes arranged in an insulating housing (4). An automatic overvoltage energy coupling trigger mechanism is connected between the upper lead electrode (1), the lower lead electrode (2) and the trigger electrode (3) arranged in the multi-layer discharge gap. By using the high solderability of the copper-chromium alloy and the automatic overvoltage energy coupling trigger mechanism to output a trigger pulse to the trigger electrode (3), it causes a trigger discharge to be preferentially formed between the trigger electrode (3) and the lower lead electrode (2), and then triggers the rapid conduction of each layer of discharge gap of the multi-layer gap overvoltage protector; The automatic overvoltage energy coupling trigger mechanism is composed of a series-connected upper coupling capacitor, a lower coupling capacitor and an isolation gap connected between the upper coupling capacitor and the lower coupling capacitor. The two input ends of the automatic overvoltage energy coupling trigger mechanism are respectively connected to the upper lead electrode (1) and the lower lead electrode (2), and the output end is connected between the trigger electrode (3) and the lower lead electrode (2).

2. An intelligent multi-layer gap overvoltage protector based on a copper-chromium alloy material with high solderability according to claim 1, Characterized in that: n pairs of discharge gaps composed of multiple copper-chromium alloy electrodes arranged in the insulating housing (4) are insulated and isolated between adjacent two electrodes with an insulating dielectric material and then connected in series through an insulating connecting rod (5) passing through each electrode and the insulating dielectric material. The insulating dielectric material is in a ring structure, and its outer contour is the same as the electrode shape; The electrodes of the topmost layer and the bottommost layer of the multi-layer discharge gap are respectively led out of the insulating housing (4) as the upper lead electrode (1) and the lower lead electrode (2), and the lead electrodes are welded on the copper-chromium alloy electrodes. A trigger electrode (3) is arranged between the nth discharge gaps and led out of the insulating housing (4). The trigger electrode (3) is insulated from the upper electrode and the lower of the nth discharge gap. The trigger electrode (3) is in a ring structure, and its outer contour is the same as the shape of each electrode of the discharge gap; The automatic overvoltage energy coupling trigger mechanism is connected between the upper lead electrode (1), the lower lead electrode (2) and the trigger electrode (3).

3. An intelligent multi-layer gap overvoltage protector based on a copper-chromium alloy material with high solderability according to any one of claims 1-2, Characterized in that: The copper-chromium alloy electrode is a sheet electrode cut from a round bar or a rectangular bar, and the copper-chromium alloy electrode is circular, square or oval.

4. An intelligent multi-layer gap overvoltage protector based on a copper-chromium alloy material with high solderability according to claim 3, Characterized in that: The gap between adjacent two copper-chromium alloy electrodes is 0.5-1.5 mm. The distance between adjacent two electrodes is equidistant or non-equidistant. The thickness of the insulating dielectric material between each copper-chromium alloy electrode is the same as the gap distance between the electrodes. The ring width of the insulating dielectric material is 5-10 mm, and a horizontal ring groove with a depth of 1.5-3 mm is provided at the middle height part inside the dielectric.

5. An intelligent multi-layer gap overvoltage protector based on copper-chromium alloy material with high solderability according to claim 3, characterized in that: the material of the trigger electrode (3) is graphite material, copper or aluminum-zinc alloy.

6. An intelligent multi-layer gap overvoltage protector based on copper-chromium alloy material with high solderability according to claim 3, characterized in that: the insulating medium between the trigger electrode (3) and the upper and lower electrodes of the nth discharge gap is ceramic.

7. An intelligent multi-layer gap overvoltage protector based on copper-chromium alloy material with high solderability according to claim 3, characterized in that: the width of the insulating medium ring between the trigger electrode (3) and the trigger electrode (3) and the upper and lower electrodes of the nth discharge gap is 1 / 4 to 1 / 3 of the size width of each discharge gap electrode.

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