CN103296661A - Lightning protection circuit of direct-current system - Google Patents
Lightning protection circuit of direct-current system Download PDFInfo
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- CN103296661A CN103296661A CN2013102112774A CN201310211277A CN103296661A CN 103296661 A CN103296661 A CN 103296661A CN 2013102112774 A CN2013102112774 A CN 2013102112774A CN 201310211277 A CN201310211277 A CN 201310211277A CN 103296661 A CN103296661 A CN 103296661A
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Abstract
The invention belongs to the design field of lightning protection circuits, and provides a lightning protection circuit of a direct-current system. The circuit comprises a primary lightning protection circuit which is in parallel connection with to-be-protected direct-current equipment in the direct-current system. A lightning current suppression circuit is in parallel connection between the primary lightning protection circuit and the to-be-protected direct-current equipment. When lightning currents are introduced through a power wire, and a part of lightning currents pass a primary lightning protection discharging place. Then, transient high impedance is formed as for remained lightning current waveforms by the lightning current suppression circuit, so that the primary lightning protection circuit can be connected quickly to discharge more lightning current energy, the lightning currents are prevented from spreading along the power wire and lightning protection effect is optimized. Meanwhile, discharging distribution of the lightning currents no longer only depends on resistance of a grounding grid and characteristic impedance of the to-be-protected equipment, so that resistance requirements on the grounding grid can be relaxed, construction and maintenance costs of the grounding grid are remarkably reduced and construction period of the grounding grid is shortened.
Description
Technical field
The invention belongs to the lightning protection circuit design field, relate in particular to a kind of lightning protection circuit that is applied in the direct current system.
Background technology
In the prior art, the Lightning Protection of direct current system is to provide one to have the very ground network of small connect ground resistance value.If the DC equipment of direct current system and alternating current equipment are together, only needing the earth point of DC equipment and ground network linked together gets final product; If the DC equipment of direct current system and alternating current equipment are not together; zoom out the station such as direct current; the base station a good distance off of DC equipment and AC power; long overhead wire probably is subjected to the intrusion of direct lightning strike or induction thunder again, so also will build a ground network specially and cooperate the lightning current of releasing with Surge Protector.
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.Yet actual ground network resistance is subjected to all multifactor influences such as ground network built environment and construction cost and can not accomplishes 0 ohm.For example, aspect construction cost, need to build very big very dark earth electrode, expend very many steel and copper material, use and have in a large number and pollute and corrosive resistance reducing agent etc.; Aspect built environment, geological environments such as high mountain, rock, gravel, salt-soda soil, Gobi desert are restricting the construction of earth work.
Simultaneously, the major loop of Surge Protector and DC equipment is connected in parallel, and has only the first wave surge protector, is equivalent to protected DC equipment in parallel with earth resistance.Because the ground network resistance can't realize 0 ohm; then Surge Protector can't make DC equipment in the direct current system fully by short circuit; then inevitable some thunder-strike current can flow through DC equipment, and whether DC equipment is damaged, 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 Lightning Protection that higher thunderbolt spoilage is still arranged.
Summary of the invention
The purpose of the embodiment of the invention is to provide a kind of lightning protection circuit of direct current system; be intended to solve in the Lightning Protection of existing direct current system; owing to have only the first wave surge protector; and Surge Protector can't be with DC equipment fully by short circuit; make the part of thunder-strike current flow through protected load equipment; lightning protection effect is uncontrollable, simultaneously because the restriction of grounded screen electric resistance value, makes the problem that the ground network construction cost is high.
The embodiment of the invention is to realize like this, a kind of lightning protection circuit of direct current system, the lightning protection circuit of described direct current system comprises two outputs being connected in parallel on DC power supply and the one-level lightning protection circuit between the lightning protection PE line, and be arranged between described one-level lightning protection circuit and the protected DC equipment and be connected on the lightning current of described DC power supply on the described protected DC equipment supply access and suppress circuit, described lightning current suppresses circuit and comprises: magnetic core inductance L 1, magnetic core inductance L 2, capacitor C 1, capacitor C 2, capacitor C 3;
Described magnetic core inductance L 1 is connected between the electrode input end of the positive pole of described DC power supply and described protected DC equipment; described magnetic core inductance L 2 is connected between the negative input of the negative pole of described DC power supply and described protected DC equipment; first end of described capacitor C 1 connects described electrode input end; second end of described capacitor C 1 connects described negative input; first end of described capacitor C 2 is connected with described electrode input end with first end of described capacitor C 1, and second end of described capacitor C 2 connects described lightning protection PE line; and connect second end and the described negative input of described capacitor C 1 by described capacitor C 3.
The lightning protection circuit of the direct current system that the embodiment of the invention proposes comprises the one-level lightning protection circuit in parallel with protected DC equipment in the direct current system; and between one-level lightning protection circuit and protected DC equipment, be in series with lightning current and suppress circuit; when lightning current is introduced by power line; part lightning current is released into ground by the one-level lightning protection; another part lightning current continues transmission; at this moment; lightning current suppresses circuit and forms the transient state high impedance at the lightning current waveform; can make on the one hand the conducting and the more lightning current energy of releasing can stop lightning current to continue to propagate along power line on the other hand as early as possible of one-level lightning protection circuit.After one-level lightning protection circuit and lightning current inhibition circuit, the lightning current energy has obtained the reduction more than 95%, has optimized lightning protection effect; Simultaneously; the resistance that the releasing of lightning current will be no longer only rely on ground network and the characteristic impedance of protected DC equipment and distribute; can relax the resistance requirement to earth resistance, thereby significantly reduce Construction of earth electrode network and maintenance cost, shorten the Construction of earth electrode network cycle.
Description of drawings
Fig. 1 is the circuit diagram of the lightning protection circuit of the direct current system that provides of the embodiment of the invention one;
Fig. 2 is a kind of circuit diagram of the one-level lightning protection circuit of the embodiment of the invention one;
Fig. 3 is the another kind of circuit diagram of the one-level lightning protection circuit of the embodiment of the invention one;
Fig. 4 is another circuit diagram of the one-level lightning protection circuit of the embodiment of the invention one;
Fig. 5 is the circuit diagram of the lightning protection circuit of the direct current system that provides of the embodiment of the invention two;
Fig. 6 is the circuit of the secondary lightning protection circuit of the embodiment of the invention two.
Embodiment
In order to make purpose of the present invention, technical scheme and advantage clearer, 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 explaining the present invention, and be not used in restriction the present invention.
Problem at the prior art existence; the lightning protection circuit of the direct current system that the present invention proposes comprises the one-level lightning protection circuit in parallel with protected DC equipment in the direct current system, and is in series with lightning current inhibition circuit between one-level lightning protection circuit and protected DC equipment.Describe implementation of the present invention in detail below in conjunction with embodiment:
Embodiment one
The embodiment of the invention one has proposed a kind of lightning protection circuit of direct current system, as shown in Figure 1, for convenience of explanation, only shows the part relevant with the embodiment of the invention one.
Specifically, the lightning protection circuit of the direct current system that the embodiment of the invention provides comprises: be connected in parallel on two outputs of DC power supply and the one-level lightning protection circuit 11 between the lightning protection PE line, be used for providing the path of releasing of lightning current; Be arranged between one-level lightning protection circuit 11 and the protected DC equipment and be connected on DC power supply and suppress circuit 12 to the lightning current on the protected DC equipment supply access.
Further, lightning current inhibition circuit 12 comprises: magnetic core inductance L 1, magnetic core inductance L 2, capacitor C 1, capacitor C 2, capacitor C 3.Wherein, magnetic core inductance L 1 is connected between the electrode input end of the positive pole of DC power supply and protected DC equipment, and magnetic core inductance L 2 is connected between the negative input of the negative pole of DC power supply and protected DC equipment; First end of capacitor C 1 connects the electrode input end of protected DC equipment, and second end of capacitor C 1 connects the negative input of protected DC equipment; First end of capacitor C 2 is connected with the electrode input end of first end of capacitor C 1 and protected DC equipment, and second end of capacitor C 2 connects lightning protection PE line, also connects second end of capacitor C 1 and the negative input of protected DC equipment by capacitor C 3.Wherein, capacitor C 1, capacitor C 2 and capacitor C 3 are individual devices, magnetic core inductance L 1 and the inductance that magnetic core inductance L 2 is high magnetic permeability, the sensibility reciprocal value is big of tolerance high pressure.
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.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; 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.Owing to adopted the connect use of discharge tube with piezo-resistance, thereby can cut off afterflow automatically, prevented the earth potential counterattack.
In another case, as shown in Figure 3, one-level lightning protection circuit 11 can further comprise a 2P air switch in the previous case.At this moment, the positive pole of DC power supply is first end that connects piezo-resistance RV1 by a K switch 1 of 2P air switch, and the negative pole of DC power supply is first end that connects piezo-resistance RV2 by another K switch 2 of 2P air switch.As lightning current by the time, the 2P air switch is because its reaction speed can trip slowly and not, lightning current is released into ground by piezo-resistance and discharge tube after by the 2P air switch; When the circuit appearance of piezo-resistance and discharge tube formation is worn out or is damaged; leakage current then increases or shorted to earth; this moment is by the afterflow of 2P air switch; electric current can cause the tripping operation of 2P air switch; disconnect from circuit with the circuit that piezo-resistance and discharge tube are constituted, avoid the protectiveness outage that goes wrong and cause whole system because of circuit that piezo-resistance and discharge tube constitute.
Under 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.At this moment, a K switch 1 of 2P air switch is first end that connects piezo-resistance RV1 by alloy-type temperature fuse F1, and a K switch 2 of 2P air switch is first end that connects piezo-resistance RV2 by alloy-type temperature fuse F2.With respect to the previous case, alloy-type temperature fuse F1 and alloy-type temperature fuse F2 can avoid having guaranteed the safe and reliable work of system because of the deterioration/inefficacy of the circuit of piezo-resistance and discharge tube formation or the disaster hidden-trouble that temporary overvoltage produces effectively.
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 the accumulation of 90% peak current of 8/20 μ s, 1.5/40 μ s, 10/700 μ s waveform appears at respectively near 24kHz, 87kHz, the 11kHz, and the low-frequency range energy of 0～100Hz only accounts for about 2.3%.Therefore, invade to the lightning current of 100KHZ as long as prevent 100HZ, just can consume the energy of lightning current more than 95%.
Based on this; the lightning protection circuit of the direct current system that the embodiment of the invention one proposes comprises the one-level lightning protection circuit 11 in parallel with protected DC equipment in the direct current system; and between one-level lightning protection circuit 11 and protected DC equipment, be in series with lightning current and suppress circuit 12; when lightning current is introduced by power line; part lightning current is released into ground by the one-level lightning protection; another part lightning current continues transmission; at this moment; lightning current suppresses circuit 12 and plays a role; form the transient state high impedance at the lightning current waveform; can make on the one hand one-level lightning protection circuit 11 conducting and the more lightning current energy of releasing can stop lightning current to continue to propagate along power line on the other hand as early as possible.After one-level lightning protection circuit 11 and lightning current inhibition circuit 12, the lightning current energy has obtained the reduction more than 95%, has optimized lightning protection effect; Simultaneously; the resistance that the releasing of lightning current will be no longer only rely on ground network and the characteristic impedance of protected DC equipment and distribute; can relax the resistance requirement to earth resistance, thereby significantly reduce Construction of earth electrode network and maintenance cost, shorten the Construction of earth electrode network cycle.
Embodiment two
The embodiment of the invention two has proposed a kind of lightning protection circuit of direct current system, as shown in Figure 5, for convenience of explanation, only shows the part relevant with the embodiment of the invention two.
Because behind one-level lightning protection circuit 11 and lightning current inhibition circuit 12; part energy near direct current in the lightning current frequency spectrum still has residue; for this part residue lightning current energy of further filtering; different with embodiment one; in embodiment two; the lightning protection circuit of direct current system also comprises: be connected in parallel on the electrode input end of protected DC equipment and the secondary lightning protection circuit 12 between negative input and the protection conductor lightning protection PE line, for providing the lightning current of flowing through to suppress the path of releasing of 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.First end of piezo-resistance RV3 connects the negative input of protected DC equipment by alloy-type temperature fuse F3, and second end of piezo-resistance RV3 connects lightning protection PE line by discharge tube G3; First end of piezo-resistance RV4 connects the electrode input end of protected DC equipment by alloy-type temperature fuse F4, and second end of piezo-resistance RV4 connects lightning protection PE line by discharge tube G4.Similarly, owing to adopted the connect use of discharge tube with piezo-resistance, thereby can cut off afterflow automatically, prevent the earth potential counterattack, and alloy-type temperature fuse F3 and alloy-type temperature fuse F4 can avoid having guaranteed the safe and reliable work of system because of the deterioration/inefficacy of the circuit of piezo-resistance and discharge tube formation or the disaster hidden-trouble that temporary overvoltage produces effectively.
With respect to embodiment one, the lightning protection circuit of the direct current system that embodiment two provides can have been optimized lightning protection effect further to releasing through the residue lightning current behind one-level lightning protection circuit 11 and the lightning current inhibition circuit 12.
The above only is preferred embodiment of the present invention, not in order to limiting the present invention, all any modifications of doing within the spirit and principles in the present invention, is equal to and replaces and improvement etc., all should be included within protection scope of the present invention.
Claims (7)
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 two outputs being connected in parallel on DC power supply and the one-level lightning protection circuit between the lightning protection PE line, and be arranged between described one-level lightning protection circuit and the protected DC equipment and be connected on the lightning current of described DC power supply on the described protected DC equipment supply access and suppress circuit, described lightning current suppresses circuit and comprises: magnetic core inductance L 1, magnetic core inductance L 2, capacitor C 1, capacitor C 2, capacitor C 3;
Described magnetic core inductance L 1 is connected between the electrode input end of the positive pole of described DC power supply and described protected DC equipment; described magnetic core inductance L 2 is connected between the negative input of the negative pole of described DC power supply and described protected DC equipment; first end of described capacitor C 1 connects described electrode input end; second end of described capacitor C 1 connects described negative input; first end of described capacitor C 2 is connected with described electrode input end with first end of described capacitor C 1, and second end of described capacitor C 2 connects described lightning protection PE line; and connect second end and the described negative input of described capacitor C 1 by described capacitor C 3.
2. the lightning protection circuit of direct current system as claimed in claim 1 is characterized in that, the lightning protection circuit of described direct current system also comprises:
Be connected in parallel on the secondary lightning protection circuit between described electrode input end and described negative input and the described protection conductor lightning protection PE line, for providing the described lightning current of flowing through to suppress the path of releasing of the residue lightning current of circuit.
3. the lightning protection circuit of direct current system as claimed in claim 2 is characterized in that, described secondary lightning protection circuit comprises: piezo-resistance RV3, piezo-resistance RV4, discharge tube G3, discharge tube G4;
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, 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 is characterized in that, described secondary lightning protection circuit also comprises: alloy-type temperature fuse F3 and alloy-type temperature fuse F4;
First end of described piezo-resistance RV3 is to connect described negative input by described alloy-type temperature fuse F3, and first end of described piezo-resistance RV4 is to connect described electrode input end by described alloy-type temperature fuse F4.
5. as the lightning protection circuit of each described direct current system of claim 1 to 4, it is characterized in that described one-level lightning protection circuit comprises: piezo-resistance RV1, piezo-resistance RV2, discharge tube G1, discharge tube G2;
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, 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.
6. the lightning protection circuit of direct current system as claimed in claim 5 is characterized in that, 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 first end that connects described piezo-resistance RV1 by described K switch 1, and the negative pole of described DC power supply is first end that connects described piezo-resistance RV2 by described K switch 2.
7. the lightning protection circuit of direct current system as claimed in claim 6 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 first end that connects described piezo-resistance RV1 by described alloy-type temperature fuse F1, and described K switch 2 is first ends that connect 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 CN103296661B (en) | 2016-02-03 |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| 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 |
| CN106936123A (en) * | 2017-03-24 | 2017-07-07 | 华为技术有限公司 | The protection device and uninterrupted power source of a kind of power supply unit |
| CN107069687A (en) * | 2017-04-07 | 2017-08-18 | 广州市晶卓照明科技有限公司 | Lightning proof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| 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 |
| CN106936123A (en) * | 2017-03-24 | 2017-07-07 | 华为技术有限公司 | The protection device and uninterrupted power source of a kind of power supply unit |
| CN107069687A (en) * | 2017-04-07 | 2017-08-18 | 广州市晶卓照明科技有限公司 | Lightning proof |
| 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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