CN103296661B - A kind of lightning protection circuit of direct current system - Google Patents
A kind of lightning protection circuit of direct current system Download PDFInfo
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- CN103296661B CN103296661B CN201310211277.4A CN201310211277A CN103296661B CN 103296661 B CN103296661 B CN 103296661B CN 201310211277 A CN201310211277 A CN 201310211277A CN 103296661 B CN103296661 B CN 103296661B
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Abstract
The invention belongs to lightning protection circuit design field, provide a kind of lightning protection circuit of direct current system.This circuit comprises the one-level lightning protection circuit in parallel with DC equipment protected in direct current system, and between one-level lightning protection circuit and protected DC equipment, be in series with lightning current suppress circuit, when lightning current is introduced by power line, part lightning current is released into ground by one-level lightning protection, afterwards, lightning current suppresses circuit to form transient state high impedance for residue lightning current waveform, one-level lightning protection circuit conducting and more lightning current energy of releasing as early as possible can be made on the one hand, lightning current can be stoped on the other hand to continue to propagate along power line, optimize lightning protection effect; Simultaneously; releasing of lightning current will no longer only rely on the resistance of ground network and the characteristic impedance of protected DC equipment and distribute; the resistance requirement to earth resistance can be relaxed, thus significantly reduce construction and the maintenance cost of ground network, shorten the construction period of ground network.
Description
Technical field
The invention belongs to lightning protection circuit design field, particularly relate to a kind of lightning protection circuit be applied in direct current system.
Background technology
In prior art, the Lightning Protection of direct current system is, provides the ground network that one has a very small connect ground resistance value.If the DC equipment of direct current system is together with alternating current equipment, only the earth point of DC equipment and ground network need be linked together; If the DC equipment of direct current system and alternating current equipment are not together; such as direct current zooms out station; the base station a good distance off of DC equipment and AC power; long overhead wire is probably subject to the intrusion of direct lightning strike or induced lightening again, so also will build a ground network specially to coordinate with Surge Protector lightning current of releasing.
In the Lightning Protection of above-mentioned direct current system, ground network resistance value is the smaller the better, and theoretic optimum value is 0 ohm.But actual ground network resistance is subject to the impact of the factors such as ground mat construction environment and construction cost and can not accomplishes 0 ohm.Such as, in construction cost, need to build very large very dark earth electrode, expend very many steel and copper material, use have pollution and corrosive resistance reducing agent etc. in a large number; In built environment, the geological environment such as high mountain, rock, gravel, salt-soda soil, Gobi desert governs the construction of earth work.
Meanwhile, the major loop of Surge Protector and DC equipment is connected in parallel, and only has first wave surge protector, is equivalent in parallel with earth resistance for protected DC equipment.Because ground network resistance cannot realize 0 ohm; then Surge Protector cannot make the DC equipment in direct current system be shorted completely; then some thunder-strike current inevitable can flow through DC equipment, and whether damaged DC equipment is, the tolerance of the DC equipment that places one's entire reliance upon self.
Therefore, the Lightning Protection of the above-mentioned direct current system that prior art provides, its lightning protection effect is uncontrollable, causes using the DC equipment of this kind of Lightning Protection still to have higher broken by lightning rate.
Summary of the invention
The object of the embodiment of the present invention is the lightning protection circuit providing a kind of direct current system; be intended to solve in the Lightning Protection of existing direct current system; owing to only having first wave surge protector; and DC equipment cannot be shorted by Surge Protector completely; a part for thunder-strike current is made to flow through protected load equipment; lightning protection effect is uncontrollable, simultaneously due to the restriction of grounded screen electric resistance value, makes the problem that ground mat construction cost is high.
The embodiment of the present invention realizes like this, a kind of lightning protection circuit of direct current system, the lightning protection circuit of described direct current system comprises the one-level lightning protection circuit be connected in parallel between two outputs of DC power supply and lightning protection PE line, and to be arranged between described one-level lightning protection circuit and protected DC equipment and to be connected on described DC power supply and suppress circuit to the lightning current on described protected DC equipment supply access, described lightning current suppresses circuit to comprise: core inductance L1, core inductance L2, electric capacity C1, electric capacity C2, electric capacity C3;
Described core inductance L1 is connected between the positive pole of described DC power supply and the electrode input end of described protected DC equipment, described core inductance L2 is connected between the negative pole of described DC power supply and the negative input of described protected DC equipment, the first end of described electric capacity C1 connects described electrode input end, second end of described electric capacity C1 connects described negative input, the first end of described electric capacity C2 is connected with the first end of described electric capacity C1 and described electrode input end, second end of described electric capacity C2 connects described lightning protection PE line, and connect second end of described electric capacity C1 and described negative input by described electric capacity C3.
The lightning protection circuit of the direct current system that the embodiment of the present invention proposes comprises the one-level lightning protection circuit in parallel with DC equipment protected in direct current system, and between one-level lightning protection circuit and protected DC equipment, be in series with lightning current suppress circuit, when lightning current is introduced by power line, part lightning current is released into ground by one-level lightning protection, another part lightning current continues transmission, now, lightning current suppresses circuit to form transient state high impedance for lightning current waveform, one-level lightning protection circuit conducting and more lightning current energy of releasing as early as possible can be made on the one hand, lightning current can be stoped on the other hand to continue to propagate along power line.After one-level lightning protection circuit and lightning current suppress circuit, lightning current energy obtains the reduction of more than 95%, optimizes lightning protection effect; Simultaneously; releasing of lightning current will no longer only rely on the resistance of ground network and the characteristic impedance of protected DC equipment and distribute; the resistance requirement to earth resistance can be relaxed, thus significantly reduce construction and the maintenance cost of ground network, shorten the construction period of ground network.
Accompanying drawing explanation
Fig. 1 is the circuit diagram of the lightning protection circuit of the direct current system that the embodiment of the present invention one provides;
Fig. 2 is a kind of circuit diagram of the one-level lightning protection circuit of the embodiment of the present invention one;
Fig. 3 is the another kind of circuit diagram of the one-level lightning protection circuit of the embodiment of the present invention one;
Fig. 4 is another circuit diagram of the one-level lightning protection circuit of the embodiment of the present invention one;
Fig. 5 is the circuit diagram of the lightning protection circuit of the direct current system that the embodiment of the present invention two provides;
Fig. 6 is the circuit of the secondary lightning protection circuit of the embodiment of the present invention two.
Embodiment
In order to make object of the present invention, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, be not intended to limit the present invention.
For prior art Problems existing; the lightning protection circuit of direct current system that the present invention proposes comprises the one-level lightning protection circuit in parallel with DC equipment protected in direct current system, and between one-level lightning protection circuit and protected DC equipment, is in series with lightning current suppresses circuit.Implementation of the present invention is described in detail below in conjunction with embodiment:
embodiment one
The embodiment of the present invention one proposes a kind of lightning protection circuit of direct current system, as shown in Figure 1, for convenience of explanation, illustrate only the part relevant to the embodiment of the present invention one.
Specifically, the lightning protection circuit of the direct current system that the embodiment of the present invention provides comprises: be connected in parallel on the one-level lightning protection circuit 11 between two outputs of DC power supply and lightning protection PE line, for providing the path of releasing of lightning current; To be arranged between one-level lightning protection circuit 11 and protected DC equipment and to be connected on DC power supply and suppress circuit 12 to the lightning current on protected DC equipment supply access.
Further, lightning current suppresses circuit 12 to comprise: core inductance L1, core inductance L2, electric capacity C1, electric capacity C2, electric capacity C3.Wherein, core inductance L1 is connected between the positive pole of DC power supply and the electrode input end of protected DC equipment, and core inductance L2 is connected between the negative pole of DC power supply and the negative input of protected DC equipment; The first end of electric capacity C1 connects the electrode input end of protected DC equipment, and second end of electric capacity C1 connects the negative input of protected DC equipment; The first end of electric capacity C2 is connected with the electrode input end of the first end of electric capacity C1 and protected DC equipment, and second end of electric capacity C2 connects lightning protection PE line and connects second end of electric capacity C1 and the negative input of protected DC equipment by electric capacity C3.Wherein, electric capacity C1, electric capacity C2 and electric capacity C3 are the individual devices of withstand high pressures, the inductance that core inductance L1 and core inductance L2 is high magnetic permeability, sensibility reciprocal value is large.
In one case, as shown in Figure 2, one-level lightning protection circuit 11 can comprise: piezo-resistance RV1, piezo-resistance RV2, discharge tube G1, discharge tube G2.The first end of piezo-resistance RV1 connects the positive pole of DC power supply, and second end of piezo-resistance RV1 connects lightning protection PE line by discharge tube G1; The first end of piezo-resistance RV2 connects the negative pole of DC power supply, and second end of piezo-resistance RV2 connects lightning protection PE line by discharge tube G2.Use with connecting of piezo-resistance owing to have employed discharge tube, thus automatically can cut off afterflow, prevent earth potential from strikeing back.
In another case, as shown in Figure 3, one-level lightning protection circuit 11 can comprise a 2P air switch in the previous case further.Now, the positive pole of DC power supply is the first end being connected piezo-resistance RV1 by a K switch 1 of 2P air switch, and the negative pole of DC power supply is the first end being connected piezo-resistance RV2 by another K switch 2 of 2P air switch.When have lightning current by time, 2P air switch due to its reaction speed slow and can not trip, lightning current is by releasing into ground by piezo-resistance and discharge tube after 2P air switch; When there is aging or damage in the circuit that piezo-resistance and discharge tube are formed; leakage current then increases or shorted to earth; now by the afterflow of 2P air switch; electric current can cause 2P air switch to trip; disconnect from circuit with the circuit that piezo-resistance and discharge tube are formed, avoid the circuit formed because of piezo-resistance and discharge tube go wrong and cause the protectiveness power-off of whole system.
In another situation, as shown in Figure 4, one-level lightning protection circuit 11 can further comprise alloy-type temperature fuse F1 and alloy-type temperature fuse F2 in the previous case.Now, a K switch 1 of 2P air switch is the first end being connected piezo-resistance RV1 by alloy-type temperature fuse F1, and a K switch 2 of 2P air switch is the first end being connected piezo-resistance RV2 by alloy-type temperature fuse F2.Relative to the previous case, the disaster hidden-trouble that alloy-type temperature fuse F1 and alloy-type temperature fuse F2 effectively can avoid the deterioration/inefficacy of the circuit formed because of piezo-resistance and discharge tube or temporary overvoltage and produce, ensure that the safe and reliable work of system.
According to research, the energy of lightning current mainly concentrates on 100Hz ~ 100KHz, lightning current energy in this frequency band accounts for more than 95% of gross energy, wherein 90% peak current accumulation of 8/20 μ s, 1.5/40 μ s, 10/700 μ s waveform appears near 24kHz, 87kHz, 11kHz respectively, and the low-frequency range energy of 0 ~ 100Hz only accounts for about 2.3%.Therefore, as long as prevent the lightning current of 100HZ to 100KHZ from invading, just the energy ezpenditure of lightning current can be fallen more than 95%.
Based on this, the lightning protection circuit of the direct current system that the embodiment of the present invention one proposes comprises the one-level lightning protection circuit 11 in parallel with DC equipment protected in direct current system, and between one-level lightning protection circuit 11 and protected DC equipment, be in series with lightning current suppress circuit 12, when lightning current is introduced by power line, part lightning current is released into ground by one-level lightning protection, another part lightning current continues transmission, now, lightning current suppresses circuit 12 to play a role, transient state high impedance is formed for lightning current waveform, one-level lightning protection circuit 11 conducting and more lightning current energy of releasing as early as possible can be made on the one hand, lightning current can be stoped on the other hand to continue to propagate along power line.After one-level lightning protection circuit 11 and lightning current suppress circuit 12, lightning current energy obtains the reduction of more than 95%, optimizes lightning protection effect; Simultaneously; releasing of lightning current will no longer only rely on the resistance of ground network and the characteristic impedance of protected DC equipment and distribute; the resistance requirement to earth resistance can be relaxed, thus significantly reduce construction and the maintenance cost of ground network, shorten the construction period of ground network.
embodiment two
The embodiment of the present invention two proposes a kind of lightning protection circuit of direct current system, as shown in Figure 5, for convenience of explanation, illustrate only the part relevant to the embodiment of the present invention two.
Due to after one-level lightning protection circuit 11 and lightning current suppress circuit 12; part energy close to direct current in lightning current frequency spectrum still has residue; in order to this some residual lightning current energy of further filtering; different from embodiment one; in embodiment two; the lightning protection circuit of direct current system also comprises: be connected in parallel on the secondary lightning protection circuit 12 between the electrode input end of protected DC equipment and negative input and protection conductor lightning protection PE line, for providing the path of releasing flowing through lightning current and suppress the residue lightning current of circuit 12.
Further, as shown in Figure 6, secondary lightning protection circuit 12 can comprise: piezo-resistance RV3, piezo-resistance RV4, discharge tube G3, discharge tube G4, alloy-type temperature fuse F3 and alloy-type temperature fuse F4.The first end of piezo-resistance RV3 connects the negative input of protected DC equipment by alloy-type temperature fuse F3, second end of piezo-resistance RV3 connects lightning protection PE line by discharge tube G3; The first end of piezo-resistance RV4 connects the electrode input end of protected DC equipment by alloy-type temperature fuse F4, second end of piezo-resistance RV4 connects lightning protection PE line by discharge tube G4.Similarly, use with connecting of piezo-resistance owing to have employed discharge tube, thus automatically afterflow can be cut off, prevent earth potential from strikeing back, and the disaster hidden-trouble that alloy-type temperature fuse F3 and alloy-type temperature fuse F4 effectively can avoid the deterioration/inefficacy of the circuit formed because of piezo-resistance and discharge tube or temporary overvoltage and produce, ensure that the safe and reliable work of system.
Relative to embodiment one, the lightning protection circuit of the direct current system that embodiment two provides can be released to the residue lightning current after one-level lightning protection circuit 11 and lightning current suppress circuit 12 further, optimizes lightning protection effect.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any amendments done within the spirit and principles in the present invention, equivalent replacement and improvement etc., all should be included within protection scope of the present invention.
Claims (5)
1. the lightning protection circuit of a direct current system, it is characterized in that, the lightning protection circuit of described direct current system comprises the one-level lightning protection circuit be connected in parallel between two outputs of DC power supply and lightning protection PE line, and to be arranged between described one-level lightning protection circuit and protected DC equipment and to be connected on described DC power supply and suppress circuit to the lightning current on described protected DC equipment supply access, described lightning current suppresses circuit to comprise: core inductance L1, core inductance L2, electric capacity C1, electric capacity C2 and electric capacity C3;
Described core inductance L1 is connected between the positive pole of described DC power supply and the electrode input end of described protected DC equipment, described core inductance L2 is connected between the negative pole of described DC power supply and the negative input of described protected DC equipment, the first end of described electric capacity C1 connects described electrode input end, second end of described electric capacity C1 connects described negative input, the first end of described electric capacity C2 is connected with the first end of described electric capacity C1 and described electrode input end, second end of described electric capacity C2 connects described lightning protection PE line, and connect second end of described electric capacity C1 and described negative input by described electric capacity C3,
Described one-level lightning protection circuit comprises: piezo-resistance RV1, piezo-resistance RV2, discharge tube G1 and discharge tube G2; The first end of described piezo-resistance RV1 connects the positive pole of described DC power supply, second end of described piezo-resistance RV1 connects described lightning protection PE line by described discharge tube G1, the first end of described piezo-resistance RV2 connects the negative pole of described DC power supply, and second end of described piezo-resistance RV2 connects described lightning protection PE line by described discharge tube G2;
Described one-level lightning protection circuit also comprises a 2P air switch, and described 2P air switch comprises K switch 1 and K switch 2; The positive pole of described DC power supply is the first end being connected described piezo-resistance RV1 by described K switch 1, and the negative pole of described DC power supply is the first end being connected described piezo-resistance RV2 by described K switch 2.
2. the lightning protection circuit of direct current system as claimed in claim 1, it is characterized in that, the lightning protection circuit of described direct current system also comprises:
Be connected in parallel on described electrode input end and the secondary lightning protection circuit between described negative input and described protection conductor lightning protection PE line, for providing the path of releasing flowing through described lightning current and suppress the residue lightning current of circuit.
3. the lightning protection circuit of direct current system as claimed in claim 2, it is characterized in that, described secondary lightning protection circuit comprises: piezo-resistance RV3, piezo-resistance RV4, discharge tube G3 and discharge tube G4;
The first end of described piezo-resistance RV3 connects described negative input, second end of described piezo-resistance RV3 connects described lightning protection PE line by described discharge tube G3, the first end of described piezo-resistance RV4 connects described electrode input end, and second end of described piezo-resistance RV4 connects described lightning protection PE line by described discharge tube G4.
4. the lightning protection circuit of direct current system as claimed in claim 3, it is characterized in that, described secondary lightning protection circuit also comprises: alloy-type temperature fuse F3 and alloy-type temperature fuse F4;
The first end of described piezo-resistance RV3 connects described negative input by described alloy-type temperature fuse F3, and the first end of described piezo-resistance RV4 connects described electrode input end by described alloy-type temperature fuse F4.
5. the lightning protection circuit of direct current system as claimed in claim 1, it is characterized in that, described one-level lightning protection circuit also comprises: alloy-type temperature fuse F1 and alloy-type temperature fuse F2;
Described K switch 1 is the first end being connected described piezo-resistance RV1 by described alloy-type temperature fuse F1, and described K switch 2 is the first ends being connected described piezo-resistance RV2 by described alloy-type temperature fuse F2.
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| CN201310211277.4A CN103296661B (en) | 2013-05-30 | 2013-05-30 | A kind of lightning protection circuit of direct current system |
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| CN201310211277.4A CN103296661B (en) | 2013-05-30 | 2013-05-30 | A kind of lightning protection circuit of direct current system |
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| CN103296661B true CN103296661B (en) | 2016-02-03 |
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104022497A (en) * | 2014-05-27 | 2014-09-03 | 华为技术有限公司 | Protective circuit and electronic equipment |
| CN104319753A (en) * | 2014-09-19 | 2015-01-28 | 中山市鸿程科研技术服务有限公司 | Lightning protection circuit of low-voltage power supply |
| CN105610143A (en) * | 2016-03-22 | 2016-05-25 | 广州市金宏骏科技工程有限公司 | Lightning protection circuit for high-voltage direct current power supply system |
| CN106936123B (en) * | 2017-03-24 | 2020-12-01 | 华为技术有限公司 | A protection device for power supply equipment and an uninterruptible power supply |
| CN107069687B (en) * | 2017-04-07 | 2020-06-09 | 广州市晶卓照明科技有限公司 | Lightning protection device |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2003116267A (en) * | 2001-10-05 | 2003-04-18 | Canon Inc | Power source |
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|---|---|---|---|---|
| CN2316756Y (en) * | 1997-12-08 | 1999-04-28 | 栖霞市供电公司 | Lighting protector for AC power |
| CN2681423Y (en) * | 2003-12-17 | 2005-02-23 | 华为技术有限公司 | Lightning protection device |
| CN201438681U (en) * | 2009-07-08 | 2010-04-14 | 广州珠江电信设备制造有限公司 | Intelligent controller for solar power supplies |
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