CN203673002U - Direct current system earth fault searching device - Google Patents
Direct current system earth fault searching device Download PDFInfo
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- CN203673002U CN203673002U CN201320751268.XU CN201320751268U CN203673002U CN 203673002 U CN203673002 U CN 203673002U CN 201320751268 U CN201320751268 U CN 201320751268U CN 203673002 U CN203673002 U CN 203673002U
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- 238000012544 monitoring process Methods 0.000 claims abstract description 31
- 238000009413 insulation Methods 0.000 claims description 29
- 238000004891 communication Methods 0.000 claims description 10
- 238000012806 monitoring device Methods 0.000 claims description 4
- 238000000034 method Methods 0.000 description 15
- 238000010586 diagram Methods 0.000 description 5
- 230000005611 electricity Effects 0.000 description 4
- 230000004907 flux Effects 0.000 description 4
- 230000006378 damage Effects 0.000 description 3
- 238000013024 troubleshooting Methods 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
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Abstract
The utility model provides a direct current system earth fault searching device, comprising a DC insulating monitoring relay acquiring positive voltage to earth, negative voltage to earth, positive resistance to earth, negative resistance to earth of a direct current system bus, a hall current sensor acquiring current signals of a DC feeder branch circuit of the direct current system, an operational amplifier connected with the hall current sensor and converting current signals into voltage signals, an A/D converter connected with the operational amplifier and converting voltage signals into digital signals, and a single-chip microcomputer which is connected with the DC insulating monitoring relay and the A/D converter. The single-chip microcomputer calculates a first current value according to a group value of the positive voltage to earth and the positive resistance to earth or a group value of the negative voltage to earth and the negative resistance to earth, calculates a second current value according the digital signals. When the first current value is equal to the second current value, fault information is output to the single-chip microcomputer. Compared with an existing device, the device does not access to AC signals in earth fault searching, so that safety of electrical equipment is ensured.
Description
Technical field
The utility model relates to power system security administrative skill field, and especially a kind of DC system earth fault is searched equipment.
Background technology
The DC power system of transformer station is specially for transformer station's various device uninterruptedly provides electric power.This system is the isolated neutral system of a long-term charging operation, but because dust or insulation fault make described generation systems earth fault, can cause malfunction or the tripping of relay protection.Described DC power system duplexure is many, in the time there is earth fault, need to find exactly faulty line with level work point, and process described earth fault.
Existing troubleshooting equipment is by adding AC signal to investigate faulty line in DC power system, and AC signal can cause certain harm to power equipments such as direct supply accumulator, relay protection devices, also can cause the security incident of electrical network when serious.
Utility model content
In view of this; the utility model provides a kind of DC system earth fault to search equipment; in the time working, the power equipments such as direct supply accumulator, relay protection device are caused to certain harm to solve existing troubleshooting equipment, when serious, can cause the problem of the security incident of electrical network.The technical solution of the utility model is as follows:
A kind of DC system earth fault is searched equipment, comprising:
Gather the DC insulation monitoring relay of the positive voltage-to-ground of straight-flow system bus, negative voltage-to-ground, positive resistance to earth and negative resistance to earth;
Gather the Hall current sensor of the current signal on the DC feeder duplexure of described straight-flow system;
Be connected with described Hall current sensor, described current signal converted to the operational amplifier of voltage signal;
Be connected with described operational amplifier, described voltage signal converted to the A/D converter of digital signal;
Be connected with described direct-current insulation monitoring device, described A/D converter respectively, calculate the first current value according to described positive voltage-to-ground, positive resistance to earth one class value or described negative voltage-to-ground, negative resistance to earth one class value, calculate the second current value according to described digital signal, in the time that described the first current value equates with described the second current value, the single-chip microcomputer of output failure message
Preferably, also comprise: be connected with described single-chip microcomputer, the display that receives described failure message and show.
Preferably, also comprise: be connected with described DC insulation monitoring relay, Hall current sensor, operational amplifier, A/D converter, single-chip microcomputer, display respectively, the power supply of power supply is provided to described DC insulation monitoring relay, Hall current sensor, operational amplifier, A/D converter, single-chip microcomputer, display.
Preferably, described DC insulation monitoring relay is connected by wireless communication module with described single-chip microcomputer, and described wireless communication module comprises:
Be connected with described direct current monitoring relay, the wireless transmit submodule that the described positive voltage-to-ground that described direct current monitoring relay is gathered, negative voltage-to-ground, positive resistance to earth and negative resistance to earth outwards send;
Be connected with described wireless transmit submodule, described single-chip microcomputer respectively, receive described positive voltage-to-ground, negative voltage-to-ground, positive resistance to earth and the negative resistance to earth that described wireless transmit submodule sends the wireless receiving submodule that transfers to described single-chip microcomputer.
Preferably, described DC insulation monitoring relay is connected by wire communication module with described single-chip microcomputer.
Preferably, in the time that described the first current value equates with described the second current value, described single-chip microcomputer output alarm signal, described equipment also comprises:
Be connected with described single-chip microcomputer, receive the alerting signal of described single-chip microcomputer output, the alarm of reporting to the police according to described alerting signal.
From above technical scheme, the utility model provides a kind of DC system earth fault to search equipment, comprising: the DC insulation monitoring relay that gathers the positive voltage-to-ground of straight-flow system bus, negative voltage-to-ground, positive resistance to earth and negative resistance to earth; Gather the Hall current sensor of the current signal on the direct current DC feeder duplexure of described straight-flow system; Be connected with described Hall current sensor, described current signal converted to the operational amplifier of voltage signal; Be connected with described operational amplifier, described voltage signal converted to the A/D converter of digital signal; Be connected with described direct-current insulation monitoring device, described A/D converter respectively, calculate the first current value according to described positive voltage-to-ground, positive resistance to earth one class value or described negative voltage-to-ground, negative resistance to earth one class value, calculate the second current value according to described digital signal, in the time that described the first current value equates with described the second current value, the single-chip microcomputer of output fault-signal.Compared with adding AC signal with existing troubleshooting equipment in the time carrying out grounding fault, the equipment that the utility model provides does not add described AC signal, detect the current signal on straight-flow system feeder assembly by Hall current sensor, the straight-flow system bus that single-chip microcomputer detects described current signal and DC insulation monitoring relay to compared with vagabond current, when representing described feeder assembly, equal Shi Ze there is earth fault, in prior art, add AC signal to bring the problem of infringement to the power equipment in described straight-flow system thereby solved, ensure the safety of power equipment in DC system earth fault search procedure.
Brief description of the drawings
In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art, to the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described below, apparently, accompanying drawing in the following describes is only embodiment of the present utility model, for those of ordinary skill in the art, do not paying under the prerequisite of creative work, other accompanying drawing can also be provided according to the accompanying drawing providing.
Fig. 1 searches the structural representation of apparatus embodiments one for a kind of DC system earth fault that the utility model provides;
Fig. 2 searches the structural representation of apparatus embodiments two for a kind of DC system earth fault that the utility model provides;
A kind of DC system earth fault that Fig. 3 provides for the utility model is searched the part-structure schematic diagram of apparatus embodiments three;
Fig. 4 searches the structural representation of apparatus embodiments four for a kind of DC system earth fault that the utility model provides.
Embodiment
Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in the utility model embodiment is clearly and completely described, obviously, described embodiment is only the utility model part embodiment, instead of whole embodiment.Based on the embodiment in the utility model, those of ordinary skill in the art are not making the every other embodiment obtaining under creative work prerequisite, all belong to the scope of the utility model protection.
Refer to Fig. 1, a kind of DC system earth fault that it shows the application provides is searched the structural representation of apparatus embodiments one.The present embodiment can comprise: DC insulation monitoring relay 101, Hall current sensor 102, operational amplifier 103, A/D converter 104, single-chip microcomputer 105.Wherein:
Described DC insulation monitoring relay 101 accesses respectively positive pole and the negative pole of described straight-flow system bus, in described DC insulation monitoring relay 101, be provided with bridge diagram, described bridge diagram can be that positive pole and negative pole are respectively established a preset value as the resistance of 60K to the earth respectively, can calculate anodal voltage-to-ground and negative pole voltage-to-ground from the electric current of described bridge diagram intermediate point output.Utilize described DC insulation monitoring relay 101 to access described straight-flow system bus, can measure anodal resistance to earth and the negative pole resistance to earth of described straight-flow system.Test philosophy is exactly positive resistance to earth and the negative resistance to earth that DC insulation monitoring relay calculates, and has utilized the corresponding computing method of sensor voltage.
Described Hall current sensor 102 calculates strength of current by the magnetic field that gathers electric current generation.Detailed process is based on magnetic balance type hall principle, it is closed loop principle, the magnetic flux producing as primary current IP concentrates in magnetic circuit by high-quality magnetic core, Hall element is fixed on and in air gap, detects magnetic flux, export reverse offset current by the multiturn coil on magnetic core, the magnetic flux producing for offsetting former limit IP, makes magnetic flux in magnetic circuit remain zero.Through the processing of special circuit, the output terminal of sensor can be exported the curent change of accurate reflection primary current.
By the electric current of positive pole and negative pole on the DC feeder duplexure of the described straight-flow system of collection of described Hall current sensor 102.The current value that Hall current sensor senses is the current value of the electric current of leakage current namely.
Described operational amplifier 103 is connected with described Hall current sensor 102, and the current signal that described Hall current sensor 102 is collected converts 0-5V standard voltage signal to.
Described A/D converter 104 is connected with described operational amplifier 103, converts described 0-5V voltage signal to digital signal.
Described single-chip microcomputer 105 is connected with described DC insulation monitoring relay 101, receives described positive voltage-to-ground, negative voltage-to-ground, positive resistance to earth and negative resistance to earth that described D.C. isolation monitoring device 101 gathers.Utilizing Current calculation formula is electric current=voltage ÷ resistance, calculates the anodal current value of described straight-flow system according to the positive positive resistance to earth of voltage-to-ground ÷, or calculates described straight-flow system negative electricity flow valuve according to the negative resistance to earth of negative voltage-to-ground ÷.
Described single-chip microcomputer 105 is connected with described A/D converter 104, receive the digital signal that described A/D converter 104 is changed, described digital signal is that the current signal on the DC feeder duplexure of the described straight-flow system that gathered by Hall current sensor 102 converts, and can calculate according to described digital signal the current value of described current signal.In the time that the current value of described current signal equates with the anodal current value of described straight-flow system or described straight-flow system negative electricity flow valuve, represent that the described DC feeder duplexure that described Hall current sensor 102 detects exists leakage circuit, be described DC feeder duplexure ground connection, trouble spot can be defined as described DC feeder duplexure.Single-chip microcomputer has Numerical Computation Function, and the single-chip microcomputer 105 in the present embodiment has used this function of single-chip microcomputer.
It should be noted that, the anodal current value of described straight-flow system or straight-flow system negative electricity flow valuve that described single-chip microcomputer 105 calculates are the first current value, and the current value of the described current signal of calculating is the second current value.
In the time that described the first current value equates with described the second current value, described single-chip microcomputer 105 is exported failure message.Wherein, described failure message comprises but the anodal voltage-to-ground, negative pole voltage-to-ground, anodal resistance to earth, negative pole resistance to earth, the described current signal that are not limited to described straight-flow system is leakage current.
From above technical scheme, a kind of DC system earth fault that the present embodiment provides is searched equipment utilization single-chip microcomputer and compares the electric current of the straight-flow system feeder branch that described Hall current sensor gathers, the anodal current value of described straight-flow system bus or the size of negative electricity flow valuve with described DC insulation monitoring relay collection, when equal, represent that described DC feeder duplexure exists earth fault.The equipment that the present embodiment provides does not inject AC signal in described straight-flow system, thereby causes damage in Earth Fault Detection process straight-flow system power equipment, and the security of testing process is provided.
In described embodiment mono-, single-chip microcomputer judges the whether ground connection of DC feeder duplexure of the described straight-flow system that described Hall current sensor detects by calculating, and export failure message, described failure message can show in display, is further analyzed earth fault information for the relevant personnel.Refer to Fig. 2, a kind of DC system earth fault that it shows the application provides is searched the structural representation of apparatus embodiments two, and in comprising embodiment mono-, 101 to 105, can also comprise: display 206 and power supply 207.Wherein:
Described display 206 is connected with described single-chip microcomputer 105, receives described failure message and shows, display format does not limit, and can be figure and or numeral.Wherein, the current signal in described failure message is that leakage current can show with the form of oscillogram.The relevant personnel can utilize described waveform to judge the ground connection degree of described detected DC feeder duplexure.
Described power supply 207 can be multi-functional power supply, be connected with described DC insulation monitoring relay 101, Hall current sensor 102, operational amplifier 103, A/D converter 104, single-chip microcomputer 105, display 106 respectively, foundation described 101 to 106 operating voltage separately, provides power supply to described DC insulation monitoring relay 101, Hall current sensor 102, operational amplifier 103, A/D converter 104, single-chip microcomputer 105, display 206.
On the basis of embodiment mono-, described single-chip microcomputer 105 can be wired connection with the connected mode of described DC insulation monitoring relay 101, also can use wireless communication module to carry out wireless connections.In the time that described connected mode is wireless connections, refer to Fig. 3, a kind of described DC system earth fault that it shows the utility model provides is searched the part-structure schematic diagram of apparatus embodiments three, and described wireless communication module comprises wireless transmit submodule 301 and described wireless receiving submodule 302.Wherein:
Described wireless transmit submodule 301 is connected with described DC insulation monitoring relay 101, and the described positive voltage-to-ground that described DC insulation monitoring relay 101 is gathered, negative voltage-to-ground, positive resistance to earth and negative resistance to earth outwards send.
Described wireless receiving submodule 302 is connected with described wireless transmit submodule 301, described single-chip microcomputer 105, receive described positive voltage-to-ground, negative voltage-to-ground, positive resistance to earth and negative resistance to earth that described wireless transmit submodule 301 sends, and by extremely described single-chip microcomputer 105 of the communication receiving.
Described wireless receiving submodule 302 needs to communicate connection before receiving the transmission information of described wireless transmit submodule 301, connection procedure is, described wireless transmit submodule 301 outwards sends handshake, when handshake that the signal receiving when described wireless receiving submodule 302 is 50HZ, receive the information that described wireless transmit submodule 301 sends, comprise described positive voltage-to-ground, negative voltage-to-ground, positive resistance to earth and negative resistance to earth.Wherein, the transmission frequency of described wireless transmit submodule 301 can be 11200HZ.
From above technical scheme, the described DC system earth fault that the present embodiment provides is searched DC insulation monitoring relay described in equipment and is connected by wireless communication module with described single-chip microcomputer, save connecting line, there is the beneficial effect of removable detection.
Refer to Fig. 4, a kind of DC system earth fault that it shows the utility model provides is searched the structural representation of apparatus embodiments four, and the present embodiment, on the basis of embodiment bis-, also comprises: alarm 408.Wherein:
Described alarm 408 is connected with described single-chip microcomputer 405, when described the first current signal calculating when described single-chip microcomputer 405 equates with described the second current signal, and can also output alarm signal.In the time that described alarm 408 receives described alerting signal, report to the police.Described alarm form can be buzzing and/or flash of light.Certainly, described power supply 408 be described 401 to 407 be respectively connected, provide power supply to described 401 to 407.
From above technical scheme, a kind of DC system earth fault that the present embodiment provides is searched equipment can be in the time there is earth fault in straight-flow system DC feeder duplexure, alarm carries out the warning of sound and/or light form, further to remind existing of earth fault information.
It should be noted that, each embodiment in this instructions all adopts the mode of going forward one by one to describe, and what each embodiment stressed is and the difference of other embodiment, between each embodiment identical similar part mutually referring to.For system class embodiment, because it is substantially similar to embodiment of the method, so description is fairly simple, relevant part is referring to the part explanation of embodiment of the method.
Finally, also it should be noted that, in this article, relational terms such as the first and second grades is only used for an entity or operation to separate with another entity or operational zone, and not necessarily requires or imply and between these entities or operation, have the relation of any this reality or sequentially.And, term " comprises ", " comprising " or its any other variant are intended to contain comprising of nonexcludability, thereby the process, method, article or the equipment that make to comprise a series of key elements not only comprise those key elements, but also comprise other key elements of clearly not listing, or be also included as the intrinsic key element of this process, method, article or equipment.The in the situation that of more restrictions not, the key element being limited by statement " comprising ... ", and be not precluded within process, method, article or the equipment that comprises described key element and also have other identical element.
Above a kind of DC system earth fault provided by the utility model being searched to equipment is described in detail, applied principle and the embodiment of specific case to the application herein and set forth, the explanation of above embodiment is just for helping to understand the application's method and core concept thereof; , for one of ordinary skill in the art, according to the application's thought, all will change in specific embodiments and applications, in sum, this description should not be construed as the restriction to the application meanwhile.
Claims (6)
1. DC system earth fault is searched an equipment, it is characterized in that, comprising:
Gather the DC insulation monitoring relay of the positive voltage-to-ground of straight-flow system bus, negative voltage-to-ground, positive resistance to earth and negative resistance to earth;
Gather the Hall current sensor of the current signal on the DC feeder duplexure of described straight-flow system;
Be connected with described Hall current sensor, described current signal converted to the operational amplifier of voltage signal;
Be connected with described operational amplifier, described voltage signal converted to the A/D converter of digital signal;
Be connected with described direct-current insulation monitoring device, described A/D converter respectively, calculate the first current value according to described positive voltage-to-ground, positive resistance to earth one class value or described negative voltage-to-ground, negative resistance to earth one class value, calculate the second current value according to described digital signal, in the time that described the first current value equates with described the second current value, the single-chip microcomputer of output failure message.
2. equipment according to claim 1, is characterized in that, also comprises:
Be connected with described single-chip microcomputer, the display that receives described failure message and show.
3. equipment according to claim 2, is characterized in that, also comprises:
Be connected with described DC insulation monitoring relay, Hall current sensor, operational amplifier, A/D converter, single-chip microcomputer, display respectively, the power supply of power supply is provided to described DC insulation monitoring relay, Hall current sensor, operational amplifier, A/D converter, single-chip microcomputer, display.
4. equipment according to claim 1, is characterized in that, described DC insulation monitoring relay is connected by wireless communication module with described single-chip microcomputer, and described wireless communication module comprises:
Be connected with described direct current monitoring relay, the wireless transmit submodule that the described positive voltage-to-ground that described direct current monitoring relay is gathered, negative voltage-to-ground, positive resistance to earth and negative resistance to earth outwards send;
Be connected with described wireless transmit submodule, described single-chip microcomputer respectively, receive described positive voltage-to-ground, negative voltage-to-ground, positive resistance to earth and the negative resistance to earth that described wireless transmit submodule sends the wireless receiving submodule that transfers to described single-chip microcomputer.
5. equipment according to claim 1, is characterized in that, described DC insulation monitoring relay is connected by wire communication module with described single-chip microcomputer.
6. according to the equipment described in claim 1 to 5 any one, it is characterized in that, in the time that described the first current value equates with described the second current value, described single-chip microcomputer output alarm signal, described equipment also comprises:
Be connected with described single-chip microcomputer, receive the alerting signal of described single-chip microcomputer output, the alarm of reporting to the police according to described alerting signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320751268.XU CN203673002U (en) | 2013-11-25 | 2013-11-25 | Direct current system earth fault searching device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320751268.XU CN203673002U (en) | 2013-11-25 | 2013-11-25 | Direct current system earth fault searching device |
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| CN203673002U true CN203673002U (en) | 2014-06-25 |
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| CN201320751268.XU Expired - Fee Related CN203673002U (en) | 2013-11-25 | 2013-11-25 | Direct current system earth fault searching device |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106680649A (en) * | 2016-12-28 | 2017-05-17 | 岭东核电有限公司 | Nuclear power plant earth fault detecting method and device |
| CN107085160A (en) * | 2017-03-29 | 2017-08-22 | 国家电网公司 | A kind of DC system grounding warning device |
| CN109725229A (en) * | 2019-01-04 | 2019-05-07 | 中国南方电网有限责任公司超高压输电公司梧州局 | A kind of detection device and method for distinguishing capacitive character and resistive transient earthing fault branch |
| CN110672984A (en) * | 2019-11-22 | 2020-01-10 | 国网四川省电力公司检修公司 | Portable direct current system ground fault detection device |
| CN110672985A (en) * | 2019-11-22 | 2020-01-10 | 国网四川省电力公司检修公司 | Non-adjacent feeder line monitoring module of transformer substation and use method |
-
2013
- 2013-11-25 CN CN201320751268.XU patent/CN203673002U/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106680649A (en) * | 2016-12-28 | 2017-05-17 | 岭东核电有限公司 | Nuclear power plant earth fault detecting method and device |
| CN107085160A (en) * | 2017-03-29 | 2017-08-22 | 国家电网公司 | A kind of DC system grounding warning device |
| CN109725229A (en) * | 2019-01-04 | 2019-05-07 | 中国南方电网有限责任公司超高压输电公司梧州局 | A kind of detection device and method for distinguishing capacitive character and resistive transient earthing fault branch |
| CN109725229B (en) * | 2019-01-04 | 2023-09-29 | 中国南方电网有限责任公司超高压输电公司梧州局 | Detection device and method for distinguishing capacitive transient ground fault branch from resistive transient ground fault branch |
| CN110672984A (en) * | 2019-11-22 | 2020-01-10 | 国网四川省电力公司检修公司 | Portable direct current system ground fault detection device |
| CN110672985A (en) * | 2019-11-22 | 2020-01-10 | 国网四川省电力公司检修公司 | Non-adjacent feeder line monitoring module of transformer substation and use method |
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Granted publication date: 20140625 Termination date: 20201125 |