CN2927440Y - Sudden-wave absorbing grounding system - Google Patents

Abstract

The utility model relates to a surge absorbing and grounding system, which comprises a flash grounding drop wire 1, a loop drop wire 7, a surge drop wire 8, a grounding otter board 4, a grounding plate 2, a ground potential limiting device 9 and a remote grounding device 10. The ground otter board 4 and the ground potential limiting device 3 are arranged into the ground to form a cloud-to-ground capacitor together with a thundercloud. The thundercloud charges are grounded via a lightning rod 14, and then through the flash grounding drop wire 1, neutralized by the opposite charges carried by the grounding otter board, thereby realizing the absorption of lighting current surges. The utility model, adopting the technical proposal of absorption first and then discharge in a grounding system, realizes the two functions of electric grounding and surge grounding. After lighting current surges are absorbed, when the potential difference between the grounding otter board and the grounding board caused by discharge of lighting continued wave or end wave impulse current and SPD surge current reaches a certain value, the ground potential limiting device is contacted and switched on for current discharge, thereby realizing the absorption and discharge of surge current and controlling the grounding potential at a relatively low amplitude.

Description

Surging absorbs grounding system

Technical field

The utility model relates to the grounding technology based on the charging neutrality theory, and particularly a kind of surging that can satisfy electrical grounding and surge impact ground connection demand absorbs grounding system.

Background technology

Ground connection is an ancient and brand-new technology, no matter be the earth as electric loop, still the earth is absorbed vessel as electric charge, all to do good ground connection, to guarantee the safe operation of personal safety and equipment.Traditional ground connection is to be laid in the ground with metal material, has been called earthing device, since the nearly generation border, human on the basis of Ohm's law, with the voltage under the linear condition, electric current theory, instruct the development grounding system, existing grounding technology is a purpose to pursue lower earth resistance.Yet, by putting into practice and discovering that there is following deficiency in the grounding system of manufacturing with prior art:

1, existing grounding technology is that the earth and thundercloud are contemplated that the cloud earth capacitance; earthing device as lead-in wire; and when the earth connects sudden strain of a muscle; set cloud earth capacitance discharge generation loop current; owing to have bottleneck effect on the contact interface of earthing device and the earth, when impacting surge arrival, form earth potential rising (accompanying drawing one); and strike back protected system by down conductor, work the mischief.The electrical grounding system of domestic recommendation in recent years also can't fundamentally solve the counterattack phenomenon that is caused because of the earth potential raising;

2, its Theoretical Calculation mode is more and complicated, and actual operation is not strong, particularly in the high resistant area of soil resistivity 〉=1000 Ω .m, earth resistance can't be dropped to reduced levels with existing grounding technology;

3, existing grounding system can be divided into surge according to its functional requirement and impact ground connection and electrical grounding.Surge is impacted ground connection and mainly comprised: lightning rod connects the ground connection of dodging the overvoltage surge that lightning current, induction surge and network system internal cause " mistake " cause; Electrical grounding mainly comprises: the ground connection of electric loop (also claiming working earthing), electrostatic protection, logical circuit benchmark.The ground connection (ground connection is impacted in surge) and the ground connection (electrical grounding) of electric loop that modern grounding technology requirement lightning rod connects the sudden strain of a muscle thunder and lightning split, and split to be infinity and mutual dried the scratching of nothing on the distance theory.Yet in the process of implementing, the technical conditions restriction because of geographical conditions, installation cost, environmental carrying capacity and earth electrode effective length is difficult to accomplish to have splitting on the practical significance;

4, the metering system of existing grounding system can not correctly, effectively be judged the ground connection situation under the impulse current condition.

In order to solve an above-mentioned difficult problem, though the human course of seeking of length slowly of having passed through is still a global difficult problem so far.

Summary of the invention

The utility model is according to closing discharge in the electric charge, conduction principle, utilize the electrical and huge capacitor function of terrestrial waveguide, provide a kind of in a cover ground connection system, the employing earlier to absorb, the technical scheme of releasing again realizes electrical grounding and two kinds of functions of surge impact ground connection, and in the environment of various soil resistivities, all there is the surging of good ground connection effect to absorb grounding system, purpose is the deficiency that overcomes prior art, it is low to make described system have an earth potential, simplicity of design, easy for installation, detect accurately, reliable operation and cost of manufacture are low, are specially adapted to the advantage of high mountain station ground connection.

Above-mentioned purpose of the present utility model is achieved through the following technical solutions:

Surging absorbs grounding system, mainly by connecing the sudden strain of a muscle downlead, the loop downlead, the surge downlead, the ground connection web plate, the ground connection pole plate, earth potential restraint device and zero potential earth electrode, the far-end earthing device is formed, its technology and prior art fundamental difference be: ground connection web plate and earth potential restraint device are set in the earth, ground connection web plate and earth potential restraint device and thundercloud constitute with air, soil is the cloud ground capacitor of medium, the earth is a charge container, because the effect of medium, the ground connection web plate can gather a large amount of charges of different polarity, when the electric field strength between cloud ground acquires a certain degree, air dielectric generation ionization, it is the capacitor breakdown of medium that ground connection web plate and thundercloud constitute with the air, thundercloud charge connects sudden strain of a muscle by lightning rod, dodge downlead and ground connection web plate institute oppositely charged and close the absorption of realization lightning current wave head in sharply through connecing.

In above-mentioned; the earth potential restraint device constitutes capacitor by top crown, bottom crown, medium; discharge electrode and bottom crown constitute the discharge voltage limiter; wherein; one end of earth potential restraint device links to each other with the ground connection web plate; the other end extremely links to each other with the far-end zero potential by the ground connection pole plate; when the continuous ripple of thunder and lightning and coda wave impulse current, SPD (surge protector) surge current are released the ground connection web plate that causes and the potential difference between the ground connection pole plate when reaching certain value; trigger the discharge of earth potential restraint device; the absorption of realization surge impulse current is released, and earth potential is suppressed at than on the low amplitude value.

In above-mentioned, form power frequency grounded circuit and electrostatic grounding loop by earth potential restraint device and zero potential earth electrode, far-end earthing device, as the overvoltage surge current that is short-circuited electric current in the electric power system and causes because of " mistake ", can absorb, release by the earth potential restraint device, the earth potential benchmark is kept relative stability.

Description of drawings

Fig. 1 be in the prior art when thunderbolt analog circuit figure;

Fig. 2 absorbs the grounding system principle schematic for the utility model surging;

Fig. 3 absorbs grounding system approximate simulation circuit diagram for the utility model surging;

Fig. 4 is the utility model earth potential restraint device structural representation.

The sudden-wave absorbing grounding system that the utility model provides has overcome the deficiency of prior art, In a cover ground connection system, adopt earlier the technical scheme that absorbs, releases again to realize electrical grounding and surge Two kinds of functions of impulse grounding, and good ground connection effect is all arranged in the environment of various soil resistivities Really. With the prior art fundamental difference be: in the earth, arrange ground connection web plate and earth potential the restriction Device, when the electric-field intensity between cloud ground arrives greatly to a certain degree, air dielectric generation ionization, thunder Close during cloud electric charge and ground connection web plate institute oppositely charged are rapid, realize the absorption of lightning current wave head. When the continuous ripple of thunder and lightning and coda wave dash current, SPD surge current release the ground connection web plate that causes with connect When the potential difference between the ground pole plate reaches certain value, namely trigger the discharge of earth potential restraint device, realize The absorption of surge current is released, and earth potential is suppressed at than on the low amplitude value.

Embodiment

Surging as shown in Figure 2 absorbs grounding system, mainly dodge downlead 1 by connecing, loop downlead 7, surge downlead 8, ground connection web plate 4, earth potential restraint device 3 and zero potential earth electrode 9, far-end earthing device 10 is formed, its technical measures are: ground connection web plate 4 and earth potential restraint device 3 are set in the earth 16, when the electric field strength between cloud ground arrives to a certain degree greatly, air dielectric generation ionization, it is the capacitor breakdown of medium that ground connection web plate 4 constitutes with the air with thundercloud, thundercloud charge connects sudden strain of a muscle by lightning rod 14, dodge downlead 1 and 4 oppositely chargeds of ground connection web plate and close in sharply through connecing, realize the absorption of lightning current wave head.

In above-mentioned, earth potential restraint device 3 (as shown in Figure 4) is by top crown 12, bottom crown 13, medium 5 constitutes capacitor, discharge electrode 6 and top crown 12, bottom crown 13 constitutes the discharge voltage limiter, wherein, one end of earth potential restraint device 3 links to each other with ground connection web plate 4, the other end links to each other with the far-end zero potential utmost point 9 through connector 11 by ground connection pole plate 2, when continuous ripple of thunder and lightning and coda wave impulse current, SPD 15 surge currents are released the ground connection web plate 4 that causes and the potential difference between the ground connection pole plate 2 when reaching certain value, promptly trigger 3 discharges of earth potential restraint device, the absorption of realization surge current is released, and earth potential is suppressed at than on the low amplitude value.

In above-mentioned, form power frequency grounded circuit and electrostatic grounding loop by earth potential restraint device 3, zero potential earth electrode 9, far-end earthing device 10, as the overvoltage surge current that is short-circuited electric current in the electric power system and causes because of " mistake ", can absorb, release by earth potential restraint device 3, the earth potential benchmark is kept relative stability.

Followingly absorb grounding system approximate simulation circuit diagram according to surging shown in Figure 3 and carry out the principle explanation:

The key problem in technology that surging absorbs grounding system is: adopt earlier the technical scheme that absorbs, releases to realize two kinds of functions of surge impact ground connection and electrical grounding in a cover ground connection is united, its division is as follows:

1, ground connection is impacted in surge

The earth as conductor is almost held infinitely-great electric capacity, and when thundercloud during near the earth, it is the capacitor C1 of medium that thundercloud and the earth form with the air, and its electric field strength satisfies following equation:

${\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="Y20062009648300111.png"\; state="\{\{state\}\}">E</figure-callout>}}_1=\frac{Q}{\mathrm{\&epsiv;}-{\mathrm{\&epsiv;}}_1}\&CenterDot;\frac{1}{A}---1.1$

The quantity of electric charge of Q----ground connection web plate

ε ₁---dielectric constant of air

A---ground connection web plate equivalence contact area

It is the capacitor C2 of medium that ground connection web plate and ground connection pole plate form with the artificiality, and its electric field strength satisfies following equation:

${\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="Y20062009648300111.png"\; state="\{\{state\}\}">E</figure-callout>}}_2=\frac{Q}{{\mathrm{\&epsiv;}}_0{\mathrm{\&epsiv;}}_2}\&CenterDot;\frac{1}{A}---1.2$

The quantity of electric charge of Q----ground connection web plate

ε ₂---artificiality dielectric constant

A---ground connection web plate equivalence contact area

The work that surging absorbs grounding system divides absorption, two processes of releasing to carry out:

The first, when the electric field strength between cloud ground greatly to a certain degree the time, cloud ground capacitor C1 punctures, suitable K switch closure, C1 institute oppositely charged is that the passage of R1 closes in sharply through resistance, realizes the absorption of lightning current wave head,, and satisfy following equation:

Ii _o?R ₁+V _C1＝0

Solve an equation:

${\mathrm{<figure-callout\; id="1"\; label="V"\; filenames="Y20062009648300111.png"\; state="\{\{state\}\}">V</figure-callout>}}_1={\mathrm{<figure-callout\; id="1"\; label="V"\; filenames="Y20062009648300111.png"\; state="\{\{state\}\}">V</figure-callout>}}_{1_0}{e}^{-\frac{t}{R_1{C}_1}}---1.3$

In the loop that the unlimited distal end zero-potential point of this process ground connection web plate and the earth constitutes certain leakage current is only arranged, its earth potential is: E ₂d

D-----ground connection web plate is to ground distance

When thunder and lightning further develops, its main component is the continuous induction point surge current that involves:

Ii＝I ₁+I ₂

Ground connection web plate voltage is: Vi=IiRi

Earth resistance formula by the netted earth electrode of half space gets:

$\mathrm{Ri}=\frac{\mathrm{\&rho;}}{4}\sqrt{\mathrm{\&pi;}/A}$

ρ---soil earth resistance rate

Earth potential is:

$\mathrm{Vi}=\frac{\mathrm{\&rho;}}{4}\sqrt{\mathrm{\&pi;}/A}(\&Integral;\frac{\mathrm{<figure-callout\; id="1"\; label="d\; q"\; filenames="Y20062009648300111.png"\; state="\{\{state\}\}">d</figure-callout>}{q}_{}{}_1}{\mathrm{dt}}+\&Integral;\frac{\mathrm{<figure-callout\; id="2"\; label="d\; q"\; filenames="Y20062009648300111.png"\; state="\{\{state\}\}">d</figure-callout>}{q}_{}{}_2}{\mathrm{dt}})t---1.4$

According to 1.4 formulas, release the ground connection web plate that causes and the potential difference between the ground connection pole plate when reaching certain value by the continuous ripple electric current of thunder and lightning, SPD surge current, promptly trigger ground voltage restraint device (P) discharge, the absorption of continuous ripple of realization thunder and lightning and coda wave electric current, SPD surge current is released, and earth potential is suppressed at than on the low amplitude value, and satisfy following equation:

${\mathrm{<figure-callout\; id="2"\; label="V"\; filenames="Y20062009648300111.png"\; state="\{\{state\}\}">V</figure-callout>}}_2={\mathrm{<figure-callout\; id="2"\; label="V"\; filenames="Y20062009648300111.png"\; state="\{\{state\}\}">V</figure-callout>}}_{2_0}{e}^{-\frac{t}{\mathrm{Ri}{C}_2}}---1.5$

2, electrical grounding

The earth has the stability of conductivity and current potential, because the electric current of static ground connection mainly conducts in the mode of power current, if adopt metallic conductor as the zero potential earth electrode, be not subjected to the restriction of the technical conditions of effective length in theory, can cause far-end zero potential earth point, to realize the stable of loop conduction and current potential, as being arranged in the electric power system, short circuit current, misoperation surge current take place, and can absorb, release by C2.

3, above-mentioned surging absorbs grounding system and may be defined as in theory: the equivalent area of ground connection web plate 4 and electric current steepness, buried layer depth, reach the surge current duration and be directly proportional, be inversely proportional to conducting voltage, the soil dielectric constant of earth potential restraint device 3, and satisfy following equation:

$A=\frac{1}{\mathrm{\&epsiv;}}\frac{\mathrm{dq}}{\mathrm{dt}}\frac{d}{V_2}t---3.1$

-lightning current steepness

D-----ground connection web plate is to ground distance

The t------surge current duration

ε-soil dielectric constant (parameter relevant) with soil resistivity

According to the authentication of analog circuit, the utlity model has stronger practical value.

Claims (4)

1. a surging absorbs grounding system, it is characterized in that: downlead (1) dodges by connecing in described system, loop downlead (7), surge downlead (8), ground connection web plate (4), ground connection pole plate (2), earth potential restraint device (3) and zero potential earth electrode (9), far-end earthing device (10) is formed, ground connection web plate (4) and earth potential restraint device (3) are set in the earth, ground connection web plate (4) and earth potential restraint device (3) constitute with air with thundercloud, soil is the cloud ground capacitor of medium, thundercloud charge connects sudden strain of a muscle by lightning rod (14), links to each other with ground connection web plate (4) through connecing sudden strain of a muscle downlead (1).

2. surging according to claim 1 absorbs grounding system, and it is characterized in that: described earth potential restraint device (3) is made up of top crown (12), bottom crown (13), medium (5), discharge electrode (6); Wherein top crown (12), bottom crown (13), medium (5) constitute capacitor, and discharge electrode (6) constitutes the discharge voltage limiter with top crown (12), bottom crown (13); One end of earth potential restraint device (3) links to each other with ground connection web plate (4), and the other end links to each other with the far-end zero potential utmost point (9) through connector (11) by ground connection pole plate (2).

3. surging according to claim 2 absorbs grounding system, it is characterized in that: releasing in order to absorption is arranged between ground connection web plate (4) and the ground connection pole plate (2) by the release surge impulse current that causes and earth potential is suppressed at than the earth potential restraint device (3) on the low amplitude value of the continuous ripple of thunder and lightning and coda wave impulse current, SPD surge current, and its discharge electrode (6) is arranged in the medium (5) of earth potential restraint device.

4. surging according to claim 1 and 2 absorbs grounding system, it is characterized in that: form power frequency grounded circuit and electrostatic grounding loop by earth potential restraint device (3) and zero potential earth electrode (9), far-end earthing device (10), in order to be short-circuited in absorption, the electric power system of releasing electric current and overvoltage surge current, the earth potential benchmark is kept relative stability.

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