Lightning arrester and lightning protection device

Abstract

The present invention belongs to the technical field of lightning prevention and control, and discloses a lightning arrester and a lightning protection device using the positioning pin. By arranging a collector wheel around the upper needle rod and arranging an adjustable capacitor below, the lightning arrester eliminates corona, can form a sufficiently long upward leader discharge, actively search for lightning and eliminate it, expand the protection range of the lightning arrester, reduce the damage of lightning strikes to buildings and electrical equipment, and is particularly suitable for application in summer lightning protection scenarios of various high-rise buildings.

Description

Technical Field

[0001] The invention belongs to the technical field of lightning prevention and control, and specifically discloses a lightning receptor and a lightning protection device using the lightning receptor. Background Art

[0002] Lightning is the rapid discharge process between one charged cloud and another charged cloud, or between a charged cloud and the ground. The discharge between clouds is mainly harmful to aircraft, while the discharge from clouds to the ground is very harmful to buildings, electronic and electrical equipment, and people and animals.

[0003] Modern meteorology has gradually improved its understanding of lightning. People have come to realize that when the electric field between the thundercloud and the ground is enhanced to a certain extent, due to the long gap distance, the streamers are not enough to penetrate the two poles, and the multiple streamers that appear gather together to strengthen the ionization of the original discharge channel, making the ionization channel longer and gradually developing into a form of gas discharge channel that develops toward the discharge electrode. This is called "leader discharge". Based on the "leader discharge" technology, technicians have developed lightning rods, so that the charges accumulated in the cloud layer are preferentially led to the earth due to the lightning rod tip, thereby preventing buildings, electronic and electrical equipment or people and animals from being struck by lightning. However, the protection angle of conventional lightning rods is small, and it is difficult to protect the affected areas of bypass lightning and side lightning. Since a large amount of charge passes through the ground wire instantly, the resistance requirements for the ground wire are relatively high.

[0004] In the past two decades, people have discovered a new understanding of the upward leader of lightning. The survival, development, maintenance and existence of the leader are only in milliseconds, and it is difficult to observe the whole process visually. The leader process is easily submerged in the subsequent discharge. With the advancement of technology, the use of high-speed camera technology in actual sites and laboratories has found the coexistence of downward leaders and multiple upward leaders.

[0005] Lightning discharge is completed in the atmosphere. Modern physics believes that if there is light in the gas discharge, there must be a recombination process of two polarity charges.

[0006] When a positively charged molecule absorbs electrons (or robs electrons from a negatively charged molecule), the energy level of the molecule will drop, and the release of this energy will appear in the form of photons of a certain wavelength. If only single-polarity charges move in the air, no light will be seen. Therefore, as long as there is light in the air, there must be two polarities of charges that recombine in motion. Strong luminescence must involve a large number of instantaneous charge recombination processes.

[0007] In addition to the discharge electrode, the oncoming discharge from the opposite electrode is indispensable for the luminescence of gas penetrating discharge. This is true for everything from fluorescent lamps and neon lights to laboratory discharges and lightning discharges in the atmosphere. The cathode picture tube is a single polarity electron beam moving in a vacuum, so no light is emitted from the inside. Only when the electron beam reaches the anode fluorescent layer and is captured by the fluorescent material, will the fluorescence on the fluorescent screen be produced. The downward leader of the thundercloud and the upward leader on the ground each carry only one kind of charge, but their luminescence can be seen, which shows that there is still a certain amount of recombination process. The other polarity charge required in the recombination process mainly comes from the high field strength at the end of the discharge leader ionizing the air.

[0008] High field strength can ionize the main air molecules. After the molecules are ionized, the molecules with the same polarity charge remain in place as an extension of the leader; the molecules (particles) with opposite polarity charge, under the action of the electric field in the channel, move along the leader channel to the leader discharge occurrence point, and continuously produce recombination processes and generate light. Since the number of ionizations is limited and the recombination process must continue to the leader discharge occurrence point, the brightness of the leader is not very high.

[0009] Luminescence is an energy output process. During the leader's forward development, it converts part of the energy stored in the thundercloud's electric field into light energy output. The energy required for the entire leader end ionization process comes from the change in the energy storage capacitor structure between the thundercloud layer and the ground.

[0010] A structural capacitor C is formed between the charged cloud layer and the ground, and the ground and the cloud layer are the two electrode plates of the capacitor. The total energy storage W of the structural capacitor C is:

[0011]

[0012] Where w is the total energy storage of the structural capacitor; q is the total charge, and C is the structural capacitance between the thundercloud and the earth.

[0013] Simplify the pilot end into a sphere with a radius of ro, and the capacitance between the upper and lower pilots is:

[0014]

[0015] Where L is the distance between the pilot end points; ro is the equivalent radius of the pilot end.

[0016] Before the breakdown discharge occurs, for a system region with a relatively stable charge, q remains unchanged. When the leader moves forward and the distance L between the discharge electrodes becomes smaller, C will increase; the energy storage w of the entire system will decrease. The reduced energy is used in the ionization process of the air and released in the form of light.

[0017] Video and physics prove that the existence of an upward leader on the ground is necessary for penetrating discharge to occur. In the atmosphere, if there is no leader coming from the opposite direction, penetrating discharge cannot form. On thunderstorm days, we can see that some downward leader discharges that develop toward the ground do not end when they land. The reason is that there is no effective upward leader in the local environment.

[0018] If a lightning rod can produce a long upward leader, its attraction effect will be enhanced; the longer the leader, the greater the enhancement effect. Supporters of early discharge lightning rods believe that it can launch an upward leader connected to the downward step leader earlier than conventional lightning protection devices, resulting in a larger protection range than conventional lightning protection devices at the same height.

[0019] However, if reliable upward leader discharge is to be implemented, the size of the capacitor in the lightning rod needs to be adjusted according to the lightning properties within the required protection area. However, the lightning rod is generally placed at a high position, which is not convenient to adjust. The designed adjustment parts may cause charge accumulation, offsetting the upward leader discharge ability of the lightning rod. In addition, there are problems such as interference between multiple lightnings and how to accumulate enough energy to produce a longer upward leader. Summary of the invention

[0020] In order to solve the problems in the background technology, the present invention provides a lightning arrester, and the specific technical solution is as follows:

[0021] A lightning arrester, comprising: a shielding cover, a collector wheel, a mounting base, an upper needle rod arranged in a vertical direction, and an upper plate and a lower plate of the same size and in a disc-shaped structure, facing each other with a set gap;

[0022] The upper needle rod, shielding cover, collector wheel, upper electrode plate and lower electrode plate are on the same axis and are all conductors; the tip of the upper needle rod is placed on the top, and the bottom end is fixed to the top of the upper electrode plate, and the bottom of the lower electrode plate is screwed on the mounting base and is connected to the ground wire;

[0023] The collector wheel is fixed to the middle part of the upper needle bar through spokes and is fixed to the mounting base through insulating support rods; the collector wheel and the upper needle bar are in unidirectional conduction, and the direction of the unidirectional conduction is that the charge can only flow from the collector wheel to the upper plate;

[0024] The shielding cover is fixed on the upper needle rod below the collector wheel and covers the upper pole plate and the lower pole plate without contact, and a rainproof shield is provided above the fixing position.

[0025] This design allows the lightning rod to utilize the insulation gap between the upper and lower plates, and use the upper metal discharge needle to absorb external charges and the electric field of the charges in the induction cloud, raising the discharge needle potential to a higher potential, greatly reducing the field strength at the top needle tip, eliminating continuous corona and the accumulation of a large amount of space charge, and meeting the basic requirements of an effective lightning rod; the collector wheel insulated from the ground is at the same floating potential as the discharge needle when not receiving lightning; when receiving lightning, the discharge needle is grounded through sparks, and the charge on the collector wheel flows to the discharge needle through the semiconductor, instantly increasing the field strength amplitude by dozens of times, forming a "field change", helping the discharge needle to generate an upward leader discharge to induce thunderstorm upward lightning. Since the lower plate is screwed to the mounting base, its height can be changed by rotation to adjust the distance between the upper and lower plates. Although there are tooth tips on the outer thread edge, they are built into the shielding cover and will not interfere with lightning.

[0026] Preferably, the conductor is made of metal material, wherein the upper electrode plate and the lower electrode plate are both made of tungsten-copper alloy with silver-plated outer surfaces.

[0027] Preferably, the distance between the upper electrode plate and the lower electrode plate is 3-10 mm.

[0028] Preferably, the spokes are semiconductors.

[0029] In this way, the spokes can serve as supports and conduct current unilaterally, reducing components and improving overall reliability.

[0030] Preferably, it also includes an inner sleeve made of insulating material, the bottom of which abuts against the top of the mounting base, the inner sleeve supports the inner surface of the shielding cover, one end of the insulating support rod is fixed to the collector wheel, and the other end is fixed to the mounting base through the shielding cover and the inner sleeve.

[0031] The present invention also provides a lightning protection device, which includes the above-mentioned lightning arrester.

[0032] Compared with the prior art, the present invention produces the following beneficial effects:

[0033] The upward leader discharge generated at the tip of the lightning receptor induces upward lightning in the thunderstorm, reduces the amplitude of the lightning current, reduces the steepness of the lightning current rise, and reduces the impact of electromagnetic shock.

[0034] The protection range is increased, and the protection angle is larger than other traditional downward lightning rods (the protection angle of traditional lightning rods is generally 30°-40°), reaching 78°, which expands the protection area and exceeds the protection range of ordinary lightning rods by more than 10 times.

[0035] The protection performance is further improved and the shielding failure rate is greatly reduced. At a protection angle of 55°, the shielding failure rate is reduced to one thousandth of that of traditional lightning arresters.

[0036] The requirements for grounding resistance have been reduced. Traditional lightning rods require a grounding resistance of less than 4Ω, but now the grounding resistance can be relaxed to 30Ω~100Ω, saving a lot of metal materials and manpower and material resources.

[0037] Multiple upward active discharges often prevent the downward discharge process of thunderclouds from happening or make the discharge invisible (avoiding "ground flash"). After installing this lightning rod, residents in areas that were often struck by lightning reported that the local thunder has become smaller, farther away, and there are fewer lightning strikes. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic cross-sectional view of a lightning arrester in an embodiment of the present invention;

[0039] Figure 2 A schematic diagram of a lightning arrester simulation test in an embodiment of the present invention;

[0040] In the figure: 1. upper needle rod; 2. fastening nut; 3. collector wheel; 4. insulating support rod; 5. shielding cover; 6. inner bushing; 7. upper plate; 8. lower plate; 9. spokes; 10. mounting base; 11. rain cover; 12. gap. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on this embodiment, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] like Figure 1 As shown, the lightning arrester of this embodiment includes: a shielding cover 5, a collector wheel 3, a mounting base 10, an upper needle rod 1 arranged in the vertical direction, and an upper electrode plate 7 and a lower electrode plate 8 of the same size and a disc-shaped structure, facing each other with a set gap; the gap 12 between the upper electrode plate 7 and the lower electrode plate 8 is 3-10mm.

[0043] The upper needle rod 1, the shielding cover 5, the collector wheel 3, the upper electrode plate 7 and the lower electrode plate 8 are on the same axis and are all made of metal; wherein, the upper electrode plate and the lower electrode plate are both made of tungsten-copper alloy with silver-plated outer surfaces.

[0044] The tip of the upper needle rod 1 is placed on the top, and the bottom end is fixed to the top of the upper electrode plate 7. The bottom of the lower electrode plate 8 is screwed on the mounting base 10 and is connected to the ground wire.

[0045] The shielding cover 5 is provided with an inner sleeve 6 made of insulating material, the bottom of which abuts against the top of the mounting base. The inner sleeve 6 supports the inner surface of the shielding cover 5 and covers the upper electrode plate 7 and the lower electrode plate 8 without contact.

[0046] The collector wheel 3 is fixed to the middle part of the upper needle rod 1 through spokes 9 made of semiconductor. The upper surface of the collector wheel 3 is limited by the fixing nut 2 , and the lower surface presses the rain cover 11 to abut against the upper through hole of the shielding cover 5 .

[0047] One end of the insulating support rod 4 is fixed to the collector wheel, and the other end is fixed to the mounting base 10 through the shielding cover 5 and the inner sleeve 6 .

[0048] The collector wheel 3 and the upper needle rod 1 are unidirectionally conductive, and the direction of the unidirectional conductive conduction is that the charges can only flow from the collector wheel 3 to the upper electrode plate 7;

[0049] The lightning rod is installed on a high pole for regional lightning prevention and control. This device constitutes another embodiment of the present specification: a lightning protection device using the above-mentioned lightning rod.

[0050] like Figure 2 As shown, the device of the present application is reduced in size according to a certain ratio, and experimental certification is carried out by simulating cloud discharge with a high-voltage power supply. No corona occurs in the tested lightning receptor itself, and the normal reading of the nanoampere ammeter is zero. The discharge gap inside the tested lightning receptor will undergo breakdown discharge under a certain high field strength. When the oscilloscope captures a discharge pulse with a microsecond time constant at intervals of several seconds to tens of seconds, there will be tens of nA of current change observation data on the charging monitoring nA ammeter on the high-voltage electrode, and the reading of the electrostatic voltage monitoring meter V will drop sharply and then rise slowly. From the analysis of the observed data, it is inferred that this microsecond discharge action instantly sends the charge emitted by the lightning receptor to the upper electrode plate, and the charge on the upper electrode plate is instantly neutralized and exhausted by the upward pulse discharge. It may be that the current is too small, no discharge occurs on the upper electrode plate, and no luminescence is observed between the electrodes. Since all measuring meters are devices with second-level time constant damping, no instantaneous change phenomenon can be observed. However, the entire test has completely simulated the active discharge process of the lightning rod in the lightning field, so the process is called intermittent active upward lightning process. Although the laboratory test of active upward lightning cannot prove that the charge segment actively released by the lightning rod has been sent to the thundercloud thousands of meters high, it has completed the verification that the lightning rod can realize the upward leader discharge process.

[0051] The device of the present application is installed in the lightning strike area, and through multiple non-continuous active discharges, the downward main discharge of the thundercloud no longer occurs, or the discharge is invisible; according to residents near the equipment installation site, the local thunder has become smaller, farther and less.

[0052] Therefore, the device can actively consume the energy stored in thunderclouds, which is beneficial to the insulation protection of the protected equipment, especially suitable for special environments such as high grounding resistance, high-rise buildings and towers.

[0053] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A lightning arrester, characterized in that: include: A shielding cover, a collector wheel, a mounting base, an upper needle rod arranged in a vertical direction, and an upper electrode plate and a lower electrode plate of the same size and a disc-shaped structure, facing each other with a set gap; The upper needle rod, shielding cover, collector wheel, upper electrode plate and lower electrode plate are on the same axis and are all conductors; the tip of the upper needle rod is placed on the top, and the bottom end is fixed to the top of the upper electrode plate, and the bottom of the lower electrode plate is screwed on the mounting base and is connected to the ground wire; The collector wheel is fixed to the middle part of the upper needle bar through spokes and is fixed to the mounting base through insulating support rods; the collector wheel and the upper needle bar are in unidirectional conduction, and the direction of the unidirectional conduction is that the charge can only flow from the collector wheel to the upper plate; The shielding cover is fixed on the upper needle rod below the collector wheel and covers the upper electrode plate and the lower electrode plate without contact, and a rainproof shield is provided above the fixed part; The conductor is made of metal material, wherein the upper electrode plate and the lower electrode plate are both made of tungsten-copper alloy with silver-plated outer surfaces; the distance between the upper electrode plate and the lower electrode plate is 3-10 mm.

2. A lightning arrester according to claim 1, characterized in that: The spokes are semiconductors.

3. A lightning arrester according to claim 2, characterized in that: It also includes an inner sleeve made of insulating material, the bottom of which abuts against the top of the mounting base, the inner sleeve supports the inner surface of the shielding cover, one end of the insulating support rod is fixed to the collector wheel, and the other end is fixed to the mounting base through the shielding cover and the inner sleeve.

4. A lightning protection device, characterized by: A lightning rod comprising any one of claims 1-3.

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