CN204203352U - Transformer iron core grounding current monitoring alarm - Google Patents
Transformer iron core grounding current monitoring alarm Download PDFInfo
- Publication number
- CN204203352U CN204203352U CN201420748803.0U CN201420748803U CN204203352U CN 204203352 U CN204203352 U CN 204203352U CN 201420748803 U CN201420748803 U CN 201420748803U CN 204203352 U CN204203352 U CN 204203352U
- Authority
- CN
- China
- Prior art keywords
- iron core
- current
- transformer
- core grounding
- feedback resistor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 42
- 238000012544 monitoring process Methods 0.000 title claims abstract description 19
- 230000006698 induction Effects 0.000 claims abstract description 29
- 238000001514 detection method Methods 0.000 claims abstract description 14
- 238000004891 communication Methods 0.000 claims abstract description 11
- 238000012360 testing method Methods 0.000 claims abstract description 8
- 239000003990 capacitor Substances 0.000 claims description 18
- 238000001914 filtration Methods 0.000 claims description 8
- 238000002955 isolation Methods 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 230000003750 conditioning effect Effects 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000004973 liquid crystal related substance Substances 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 229920004934 Dacron® Polymers 0.000 description 1
- 229910000976 Electrical steel Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000005674 electromagnetic induction Effects 0.000 description 1
- 125000002534 ethynyl group Chemical group [H]C#C* 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 239000005020 polyethylene terephthalate Substances 0.000 description 1
- 230000003449 preventive effect Effects 0.000 description 1
- 230000011664 signaling Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Landscapes
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
Transformer iron core grounding current real-time monitoring and alarming device, comprises current transformer, and described current transformer has center pit, and described current transformer also comprises through the iron core grounding line of center pit and the second siding ring with the mutual inductance of iron core grounding line; And gather the testing circuit of second siding ring electric current; Described current detection circuit comprises the induction current amplifier be connected with second siding ring, the A/D converter be connected with induction current amplifier out, and the scm managing system be connected with A/D converter; Described scm managing system is connected with communication interface, also comprises the clock oscillator and storage unit that are connected with scm managing system.The utility model earth wire electric current carries out the isolation amplifier of mutual inductance type, significantly improves measuring accuracy and testing reliability, directly provides judged result and be delivered to Surveillance center by communication interface, achieves unmanned and on-line real-time measuremen judgement.
Description
Technical field
The utility model belongs to field of power electronics, relates to the ground wire current detection technology of transformer, particularly a kind of transformer iron core grounding current real-time monitoring and alarming device.
Background technology
In transformer device structure, coil and iron core, between iron core and casing, there is certain stray capacitance, power transformer is when normally running, non-uniform electric field is produced around electrified coil, under electric field action, be coupled by stray capacitance, floating potential over the ground will be produced, cause iron core and coil to reach and puncture insulation, produce shelf depreciation etc.Therefore, need the electromotive force of normal induction to discharge, make them all be in zero potential, therefore need the reliability ground connection of designing and completing a bit.
But because iron core magnetic flux density is uneven, short near iron core inside casing magnetic circuit, magnetic resistance is little, long near iron core housing magnetic circuit, and magnetic resistance is large, so when appearance more than 2 ground connection, just can cause potential difference (PD), 2 and multiple spot potential difference (PD) will form loop, generation circulation each other.Circulation may from milliampere level to tens of ampere, and cause iron core vortex to generate heat, and causes silicon steel sheet insulating layer to damage, even involves coil insulation, make oil temperature increase, occur methane, excessive acetylene etc., cause Accident of Transformer to occur.
By upper conclusion: the necessary one point earth of iron core, but never allow and multipoint earthing at 2.For realizing aforementioned grounding requirement, ground wire connected mode as shown in Figure 1 installed by transformer: can see from a of Fig. 1, and iron core metal wire 3, through conduit 2, is drawn by transformer 1 in transformer body, and access underground, realizes the protective effect of one point earth.But can not automatically inform with or without during more than 2 o'clock earth fault, and majority is as shown in figure b, by artificial hand-held pincerlike meter 4, regular or the irregular measurement carrying out ground current, according to regulation in DL/T 596-199 " power equipment preventive trial directive/guide ": when core insulation is normal, ground current is not more than 0.1A, and this is distinguishing rule.If exceed normal value 0.1A, then illustrate there is problem, exceed data larger simultaneously, show that problem is more, one is have 2 even multipoint earthings, and two is that grounding phenomenon is also got over serious, need carry out necessary maintenance process.
Transformer core grounding, by manual testing, the not only original backwardness of method, the more important thing is can not Timeliness coverage problem, especially, when current unattended substation is extensively universal, patrol and detection chance greatly reduces, more difficult discovery fault promptly and accurately, accident treatment opportunity will be incured loss through delay, even cause the state of affairs to expand.
Utility model content
For overcome existing transformer core grounding line current detection method exist need Attended mode manual testing, be difficult to discovery fault promptly and accurately, the defect on accident treatment opportunity may be incured loss through delay, the utility model discloses a kind of transformer iron core grounding current real-time monitoring and alarming device.
Transformer iron core grounding current real-time monitoring and alarming device described in the utility model, for measuring transformer iron core grounding line current, comprise current transformer, described current transformer has center pit, and described current transformer also comprises through the iron core grounding line of center pit and the second siding ring with the mutual inductance of iron core grounding line;
And gather the testing circuit of second siding ring electric current; Described current detection circuit comprises the induction current amplifier be connected with second siding ring, the A/D converter be connected with induction current amplifier out, and the scm managing system be connected with A/D converter; Described scm managing system is connected with communication interface, also comprises the clock oscillator and storage unit that are connected with scm managing system.
Concrete, described second siding ring terminal ground connection, described induction current amplifier comprises commutation diode, filter capacitor, comparer, reference voltage generator; Described commutation diode positive and negative electrode is connecting secondary lateral coil starting point and comparer in-phase input end respectively, and described filter capacitor is connected between commutation diode negative pole and ground, and described reference voltage generator output terminal connects comparer inverting input;
Also comprise quiescent potential initialization circuit, described quiescent potential initialization circuit is the first divider resistance string be connected between the DC power supply terminal of induction current amplifier and ground; The divider node of described first divider resistance string connects commutation diode negative pole.
Further, described reference voltage generator is the second divider resistance string be connected between the DC power supply terminal of induction current amplifier and ground, the output terminal of divider node reference voltage generator.
Further, positive feedback resistor string is connected with between the output terminal of described comparer and the negative pole of commutation diode, described positive feedback resistor string is composed in series by the first positive feedback resistor and the second positive feedback resistor, wherein the first positive feedback resistor connects comparator output terminal, and the second positive feedback resistor connects commutation diode negative pole;
First positive feedback resistor resistance is greater than the second positive feedback resistor, and the first positive feedback resistor is connected comparer in-phase input end with the intermediate node of the second positive feedback resistor.
Preferably, described induction current amplifier also comprises power circuit, described power circuit comprises supply transformer and three terminal regulator, described supply transformer primary side is connected with utility grid, secondary side starting point and terminal are connected a commutation diode positive pole respectively, two commutation diode negative poles link together and connect three terminal regulator input end, described secondary side are also connected with the centre tap of ground connection; First output terminal of described three terminal regulator as the direct current forward output terminal of power circuit, the second output head grounding of three terminal regulator.
Further, be connected with the first filter capacitor between the input end of described three terminal regulator and ground, be connected with the second filter capacitor between the first output terminal of described three terminal regulator and ground, described first filter capacitor frequency filtering is less than the second filter capacitor.
Further, also comprise instruction branch road, described instruction branch road comprises and is connected on light emitting diode between direct current forward output terminal and ground and current-limiting resistance.
Preferably, described A/D converter is MAX125.
Preferably, the upper PC be connected with scm managing system and key input unit is also comprised.
Concrete, described detection mutual inductor is BH-066 type.
Adopt transformer iron core grounding current real-time monitoring and alarming device described in the utility model, transformer grounding line current is carried out to the isolation amplifier of mutual inductance type, significantly improve measuring accuracy and testing reliability, introduce scm managing system simultaneously and calculation process judgement is carried out to collection signal, directly provide judged result and be delivered to Surveillance center by communication interface, achieving unmanned and on-line real-time measuremen judgement.
Accompanying drawing explanation
Fig. 1 is the detection method schematic diagram of prior art to transformer iron core grounding current;
Fig. 2 is the structural representation of transformer iron core grounding current real-time monitoring and alarming device described in the utility model;
Fig. 3 is a kind of embodiment schematic diagram of induction current amplifier described in the utility model.
Embodiment
Below in conjunction with accompanying drawing, embodiment of the present utility model is described in further detail.
Transformer iron core grounding current real-time monitoring and alarming device described in the utility model, for measuring transformer iron core grounding line current, comprise current transformer, described current transformer has center pit, and described current transformer also comprises through the iron core grounding line of center pit and the second siding ring with the mutual inductance of iron core grounding line;
And gather the testing circuit of second siding ring electric current; Described current detection circuit comprises the induction current amplifier be connected with second siding ring, the A/D converter be connected with induction current amplifier out, and the scm managing system be connected with A/D converter; Described scm managing system is connected with communication interface, also comprises the clock oscillator and storage unit that are connected with scm managing system.
The usual wound core ground wire of second siding ring helically surrounds shape; when ground wire has abnormal current; according to electromagnetic induction principle; the abnormal current of iron core grounding line is produced sensor current signal by second siding ring induction, and sensor current signal is input to the induction current amplifier in current detection circuit
Provide a kind of embodiment structural representation of the present utility model as shown in Figure 2, what send here from the current detection circuit of front end is simulating signal, therefore need first to utilize A/D converter to do analog/digital signal conversion (A/D conversion), the device model of A/D conversion used can be MAX125, scm managing system is sent to by data bus and address bus again, to determine whether to produce multipoint earthing of iron core of transformer after A/D converts.
Device inside is provided with clock oscillator, with produce year, month, day, hour, min, second isochronon signal, its purposes is when both can walk, again can record trouble time of origin, is convenient to crash analysis process.The model of crystal clock oscillator used is specifically as follows DS12887, and storage unit is for storing the record of initial parameter storage and the judged result carrying out judging.
Although the utility model is based on unattended object, but still can the input equipments such as keyboard and mouse being set, conveniently patrolling and examining staff to judging that parameter is arranged and command operating.By arranging keyboard receiving processor, keyboard also can input monitored ground path, sensor number, voltage threshold value, warning initiation value, time adjustment, communication protocol etc.; Can retrieve for examination in conjunction with LCD liquid crystal display screen and inquire about again.The model of receiving processor used can be JCDL8279.
The result that scm managing system is made, through communication interface, different signaling interfaces and communication protocol is selected with baud rate etc. by the on-the-spot communication protocol adapted to, such as RS232, RS485 interface etc. pass the signal along on grid, make centralized control center supervisor and relevant leader also can understand and grasp transformer core grounding situation in the distance, make crash analysis in time to process with investigation, to ensure whole transformer energy safety, stable operation.
Can also arrange local display, the display alarm of the machine LCD liquid crystal display is sent on the road that result is parallel, and can also arrange host computer, another road signal sends host computer to, makes subsequent treatment.
When more than 2 ground connection appear in monitored transformer core, will produce ground current, collected signal sends scm managing system to and compares judgement.
Output alarm signal is stored the time, transformer numbering etc. of the generation of this fault on the one hand by unit records, on the other hand signal is uploaded Surveillance center by communication interface, can also upload local display screen or do display alarm.
Current transformer can select existing ripe model, that ground current may reach tens amperes according to embody rule situation of the present utility model, preferred use Shanghai switchgear plant 0.5 grade of producing, BH-0.66 type the current transformer of 75/5 ampere, this current transformer accuracy of detection is high, and volume size is little, be suitable for being arranged on the position being easy in transformer grounding line approach fix, observe.
The effect of induction current amplifier is the induction current of detection secondary side appearance and output judges signal, provide a kind of embodiment of described induction current amplifier as shown in Figure 3, described second siding ring terminal ground connection, described induction current amplifier comprises commutation diode D3, filter capacitor C3, comparer IC1, reference voltage generator; Described commutation diode positive and negative electrode is connecting secondary lateral coil starting point and comparer in-phase input end respectively, and described filter capacitor is connected between commutation diode negative pole and ground, and described reference voltage generator output terminal connects comparer inverting input; Also comprise quiescent potential initialization circuit, described quiescent potential initialization circuit is the first divider resistance string be connected between the DC power supply terminal of induction current amplifier and ground; The divider node of described first divider resistance string connects commutation diode negative pole.
Visible in Fig. 3, two end points S1, S2 of current transformer core ground wire are through current transformer core and second siding ring, the ground current signal collected is exported at second siding ring end points S3, S4 end, through commutation diode D3 half-wave rectification, filter capacitor C3 filtering, coordinates the work of subsequent conditioning circuit with DC form.
Be current signal due to what collect from second siding ring end, for this reason, be converted to voltage signal over the ground through resistance R3, to meet integrated transporting discharging with the structural principle of voltage for main work.Two divider resistances R2, R3 of first divider resistance string also have and produce DC point by source voltage, to adapt to the object of the input voltage working range of comparer, such as supply voltage 12V, the input voltage working range of comparer IC1 is within the scope of 2-8V, then the ratio that can arrange R2 and R3 makes the DC voltage value of divider node at about 4V.
As shown in Figure 3
,reference voltage generator for being connected on the second divider resistance string between the DC power supply terminal of induction current amplifier and ground, can be composed in series by divider resistance R5 and R6, and the common port of divider node and R5 and R6 is as the output terminal of reference voltage generator.
A kind of preferred implementation is be connected with positive feedback resistor string between the output terminal and the negative pole of commutation diode of comparer, described positive feedback resistor string is composed in series by the first positive feedback resistor R7 and the second positive feedback resistor R4, wherein the first positive feedback resistor connects comparator output terminal, and the second positive feedback resistor connects commutation diode; First positive feedback resistor resistance is greater than the second positive feedback resistor, and the first positive feedback resistor is connected comparer in-phase input end with the intermediate node of the second positive feedback resistor.
The effect of above-mentioned positive feedback resistor string is the enlargement factor increasing voltage signal.Such as arrange:
R4=10k Ω, R7=100k Ω, then gain amplifier:
Comparator voltage enlargement factor A=1+R7/R4=1+100/10=11 doubly.
To adopt BH-0.66 type current transformer, first and second ER effect is 1:15 than pass, for less grounding small current---as 1A, after the 1:15 no-load voltage ratio of current transformer, secondary have electric current:
1÷15＝0.067A
Do in voltage transitions through resistor current again, even if 1:1 carries out, also can only have 0.067V, be difficult to accordingly promote subsequent conditioning circuit.But after adding gain amplifier, then have:
0.067 × 11=0.74V, namely comparator output terminal OUT produces the magnitude of voltage of 0.74V, may produce logic effect completely, promotes subsequent conditioning circuit or make further A/D to sample.
Induction current amplifier can adopt dc-battery to power, but for avoiding frequently changing battery, reduce costs, also the civil power that transformer connects can be converted into direct current to use as induction current amplifier power supply, the utility model provides a kind of power circuit of powering for induction current amplifier, described power circuit comprises supply transformer B and three terminal regulator WY1, described supply transformer primary side is connected with utility grid, secondary side starting point and terminal are connected a commutation diode positive pole respectively, two commutation diode D1 link together with D2 negative pole and are connected three terminal regulator input end, described secondary side is also connected with the centre tap of ground connection, first output terminal of described three terminal regulator as the direct current forward output terminal of power circuit, the second output head grounding of three terminal regulator.
As shown in Figure 3,220v electric main is introduced by exchanging AC terminal, through the primary side of K switch 1, protective tube BX arrival supply transformer B, by tapped setting, equivalent alternating voltage can be exported at secondary side, through commutation diode D1, D2 full-wave rectification, then export direct supply through three terminal regulator WY1, thus, AC and DC conversion is completed.
Three terminal regulator can select W7812, the first filter capacitor C1 can be connected with for low frequency filtering between the input end of three terminal regulator and ground, the second filter capacitor C2 is connected with for medium-high frequency filtering between first output terminal of described three terminal regulator and ground, C1 can select electrochemical capacitor, and C2 selects electric capacity of the dacron to do low, medium-high frequency filtering respectively.Wherein low frequency filtering electric capacity C1 is arranged between three terminal regulator input end and ground, because the voltage of input end is changed by 50 hertz of civil powers, comprise a large amount of low-frequency noise, therefore C1 capacitance is comparatively large, can reach hundred microfarads or thousand microfarad magnitudes, after overcommutation slicing and three terminal regulator, three terminal regulator may produce the high-frequency noises of frequency far above civil power 50 hertz frequency, therefore C2 capacitance is less, in microfarad or nanofarad magnitude, for filtering high-frequency noises.
Can also arrange instruction branch road, comprise light emitting diode Fg1 and current-limiting resistance R1, when feeder ear has DC voltage, lumination of light emitting diode instruction is working properly.
Previously described is each preferred embodiment of the present utility model, preferred implementation in each preferred embodiment is if not obviously contradictory or premised on a certain preferred implementation, each preferred implementation can stack combinations use arbitrarily, design parameter in described embodiment and embodiment is only the utility model proof procedure in order to clear statement utility model people, and be not used to limit scope of patent protection of the present utility model, scope of patent protection of the present utility model is still as the criterion with its claims, the equivalent structure change that every utilization instructions of the present utility model and accompanying drawing content are done, in like manner all should be included in protection domain of the present utility model.
Claims (10)
1. transformer iron core grounding current real-time monitoring and alarming device, for measuring transformer iron core grounding line current, it is characterized in that, comprise current transformer, described current transformer has center pit, and described current transformer also comprises through the iron core grounding line of center pit and the second siding ring with the mutual inductance of iron core grounding line;
And gather the testing circuit of second siding ring electric current; Described current detection circuit comprises the induction current amplifier be connected with second siding ring, the A/D converter be connected with induction current amplifier out, and the scm managing system be connected with A/D converter; Described scm managing system is connected with communication interface, also comprises the clock oscillator and storage unit that are connected with scm managing system.
2. transformer iron core grounding current real-time monitoring and alarming device as claimed in claim 1, it is characterized in that, described second siding ring terminal ground connection, described induction current amplifier comprises commutation diode, filter capacitor, comparer, reference voltage generator; Described commutation diode positive and negative electrode is connecting secondary lateral coil starting point and comparer in-phase input end respectively, and described filter capacitor is connected between commutation diode negative pole and ground, and described reference voltage generator output terminal connects comparer inverting input;
Also comprise quiescent potential initialization circuit, described quiescent potential initialization circuit is the first divider resistance string be connected between the DC power supply terminal of induction current amplifier and ground; The divider node of described first divider resistance string connects commutation diode negative pole.
3. transformer iron core grounding current real-time monitoring and alarming device as claimed in claim 2, it is characterized in that, described reference voltage generator is the second divider resistance string be connected between the DC power supply terminal of induction current amplifier and ground, the output terminal of divider node reference voltage generator.
4. transformer iron core grounding current real-time monitoring and alarming device as claimed in claim 2, it is characterized in that, positive feedback resistor string is connected with between the output terminal of described comparer and the negative pole of commutation diode, described positive feedback resistor string is composed in series by the first positive feedback resistor and the second positive feedback resistor, wherein the first positive feedback resistor connects comparator output terminal, and the second positive feedback resistor connects commutation diode negative pole;
First positive feedback resistor resistance is greater than the second positive feedback resistor, and the first positive feedback resistor is connected comparer in-phase input end with the intermediate node of the second positive feedback resistor.
5. transformer iron core grounding current real-time monitoring and alarming device as claimed in claim 1, it is characterized in that, described induction current amplifier also comprises power circuit, described power circuit comprises supply transformer and three terminal regulator, described supply transformer primary side is connected with utility grid, secondary side starting point and terminal are connected a commutation diode positive pole respectively, two commutation diode negative poles link together and connect three terminal regulator input end, described secondary side are also connected with the centre tap of ground connection; First output terminal of described three terminal regulator as the direct current forward output terminal of power circuit, the second output head grounding of three terminal regulator.
6. transformer iron core grounding current real-time monitoring and alarming device as claimed in claim 5, it is characterized in that, the first filter capacitor is connected with between the input end of described three terminal regulator and ground, be connected with the second filter capacitor between first output terminal of described three terminal regulator and ground, described first filter capacitor frequency filtering is less than the second filter capacitor.
7. transformer iron core grounding current real-time monitoring and alarming device as claimed in claim 5, is characterized in that, also comprise instruction branch road, and described instruction branch road comprises and is connected on light emitting diode between direct current forward output terminal and ground and current-limiting resistance.
8. transformer iron core grounding current real-time monitoring and alarming device as claimed in claim 1, it is characterized in that, described A/D converter is MAX125.
9. transformer iron core grounding current real-time monitoring and alarming device as claimed in claim 1, is characterized in that, also comprise the upper PC and key input unit that are connected with scm managing system.
10. transformer iron core grounding current real-time monitoring and alarming device as claimed in claim 1, it is characterized in that, described detection mutual inductor is BH-066 type.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420748803.0U CN204203352U (en) | 2014-12-04 | 2014-12-04 | Transformer iron core grounding current monitoring alarm |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420748803.0U CN204203352U (en) | 2014-12-04 | 2014-12-04 | Transformer iron core grounding current monitoring alarm |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204203352U true CN204203352U (en) | 2015-03-11 |
Family
ID=52661297
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420748803.0U Active CN204203352U (en) | 2014-12-04 | 2014-12-04 | Transformer iron core grounding current monitoring alarm |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204203352U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104483534A (en) * | 2014-12-04 | 2015-04-01 | 国网四川省电力公司甘孜供电公司 | Intelligent monitoring alarm for grounding current of transformer core |
-
2014
- 2014-12-04 CN CN201420748803.0U patent/CN204203352U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104483534A (en) * | 2014-12-04 | 2015-04-01 | 国网四川省电力公司甘孜供电公司 | Intelligent monitoring alarm for grounding current of transformer core |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105116296A (en) | Special fault indicator for high-voltage power transmission network cable line | |
| CN105676092B (en) | Electric substation's power cable insulation level monitoring method and system | |
| CN106896300B (en) | The monitoring device of power cable connector temperature and PD parameter | |
| CN104483534A (en) | Intelligent monitoring alarm for grounding current of transformer core | |
| CN110082635A (en) | It is a kind of can self study multi-functional fault electric arc detector | |
| CN104483526A (en) | Grounding current induction monitor for power grid transformer | |
| CN103616616A (en) | Fault detection method for large-scale grounding grid | |
| CN107781646A (en) | Natural gas monitoring system | |
| CN110967595A (en) | Portable non-contact distribution network ground fault detection positioning system | |
| CN110221140A (en) | Distribution power automation terminal intelligent detecting instrument | |
| CN204203352U (en) | Transformer iron core grounding current monitoring alarm | |
| CN211121641U (en) | High-voltage passive wireless temperature online monitoring system | |
| CN205027858U (en) | Special fault indicator of high -tension transmission net cable run | |
| CN107546856A (en) | A kind of ring-main unit comprehensive monitoring system | |
| CN105823949A (en) | Lightning arrester online monitor | |
| CN204256025U (en) | Network transformer ground current mutual inductance monitor | |
| CN103116063A (en) | Transformer iron core ground connection electric current monitor | |
| CN207232314U (en) | A kind of Insulation Inspection System of DC trolley locomotive rectifier power source | |
| CN202814597U (en) | High-voltage power transmission line temperature measuring system | |
| CN205157663U (en) | Remote online arrester monitoring device | |
| CN205176158U (en) | Electric capacity type current transformer on -line measuring device | |
| CN210954297U (en) | Online real-time measuring device for grounding condition of electrical equipment | |
| CN207456632U (en) | A kind of transformer temperature monitor based on heat transfer | |
| CN112505430A (en) | Passive high-voltage capacitor capacitance online monitoring system and method | |
| CN111781537A (en) | Transformer substation grounding grid safety state on-line monitoring system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |