CN202749185U - DC (direct current) attenuation frequency conversion demagnetization device - Google Patents
DC (direct current) attenuation frequency conversion demagnetization device Download PDFInfo
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- CN202749185U CN202749185U CN 201220454245 CN201220454245U CN202749185U CN 202749185 U CN202749185 U CN 202749185U CN 201220454245 CN201220454245 CN 201220454245 CN 201220454245 U CN201220454245 U CN 201220454245U CN 202749185 U CN202749185 U CN 202749185U
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Abstract
The utility model discloses a DC (direct current) attenuation frequency conversion demagnetization device which comprises a DC attenuation frequency conversion source (8), a control acquisition unit (7), an attenuation frequency conversion signal current detection unit (9), an attenuation frequency conversion signal voltage detection unit (10) and a demagnetization output unit (11), wherein an output end of the DC attenuation frequency conversion source (8) is connected with an input end of the demagnetization output unit (11); an output end of the demagnetization output unit (11) is connected with a high-voltage end of electric equipment to be demagnetized; the attenuation frequency conversion signal current detection unit (9) and the attenuation frequency conversion signal voltage detection unit (10) are connected with the output end of the DC attenuation frequency conversion source (8) respectively, and the output end is connected with the control acquisition unit (7); and a signal output end of the control acquisition unit (7) is connected with an expert analysis system (13), and a control output end is connected with the DC attenuation frequency conversion source (8). The device disclosed by the utility model demagnetizes the electric equipment by use of the DC attenuation frequency conversion signal, has small size and light weight, and realizes thorough demagnetization, quick demagnetization and simple measurement of residual magnetism.
Description
Technical field
The utility model belongs to electric power system inductive equipment technical field, the remanent magnetism that relates to the large perceptual electric equipment of the large capacity high voltage of a kind of electric power system is eliminated and the measurement of remanent magnetism, and particularly a kind of power transformer, instrument transformer have been measured the elimination of remanent magnetism behind the D.C. resistance and the measurement of remanent magnetism.
Background technology
Since the intrinsic hysteresis of ferromagnetic material, meeting residual remanent magnetism in iron core after the power transformer instrument transformer being carried out the operations such as voltage ratio, direct current resistance m easurem ent.Because the existence of remanent magnetism, remanent magnetism unshakable in one's determination makes the transformer core half cycle saturated when transformer puts into operation, produces a large amount of exciting currents, and can carry a large amount of harmonic waves in the exciting current.This has not only increased the reactive power consumption of transformer, and because affecting the quality of electrical network, more can cause the relay protector misoperation, even can make the superior system tripping operation of electrical network, causes certain economic loss.Remanent magnetism has our harm:
1, causes the protective relaying device malfunction of transformer, make the again and again failure that puts into operation of transformer;
The voltage that produces when 2, transformer outlet short trouble excises is uprushed, and brings out malfunction for tranformer protection, and each side load of transformer is all had a power failure;
3, the no-load transformer in A power station taps into the magnetizing inrush current of power generation, brings out that the transformer that is moving in contiguous other B power stations, C power station etc. produces " and echo surge current " (sympathetic inrush) and mistrip causes large-area power-cuts;
4, the magnetizing inrush current that numerical value is very large can cause transformer and circuit breaker excessive impaired because of electric power;
5, bring out the manipulation overvoltage, damage the electric equipment in the electrical network;
6, the DC component in the magnetizing inrush current causes the current transformer magnetic circuit excessively to be magnetized and significantly reduces the performance factor of certainty of measurement and protective relaying device;
7, a large amount of harmonic waves in the magnetizing inrush current cause serious pollution to the electrical network quality of power supply.
8, cause line voltage to rise sharply or rapid drawdown, affect other electric equipments normal operations.
For example, close a floodgate because of the single-phase 70MVA main transformer of Dunhuang 750kV band remanent magnetism in December, 2011, causes Tibet 800kV direct current trip accident.
In sum, at the residual remanent magnetism that the power transformer instrument transformer is carried out in iron core, produce after the operations such as voltage ratio, direct current resistance m easurem ent, be apparent to our harm.So we are very important in the demagnetization work before the power transformer instrument transformer puts into operation.Just can expect realizing with alternating current method from the erasure effect people, because it also is the most familiar methods only of people, and it can eliminate residual remanent magnetism thoroughly at once.But the equipment of AC erasing is only suitable for the manufacturer of transformer to be used in laboratory, because it is huge heavy again, is not suitable for very much the field, forms complexity, complex operation.
Summary of the invention
The purpose of this utility model mainly is to solve magnetizing inrush current that remanent magnetism produces and harmonic wave to the harm of power transformer instrument transformer and whole electrical network.The remanent magnetism elimination of the large perceptual electric equipment of the large capacity high voltage of a kind of electric power system and the device of measuring are provided.
For reaching above purpose, the utility model takes following technical scheme to be achieved:
A kind of direct current decay frequency conversion degaussing gear comprises direct current decay frequency conversion source, control collecting unit, decay frequency variation signal current detecting unit, decay frequency variation signal voltage detection unit, demagnetization output unit.
The output in described direct current decay frequency conversion source links to each other with the input of demagnetization output unit, and the output of described demagnetization output unit is connected to the high-pressure side of the electric equipment for the treatment of demagnetization.
Described decay frequency variation signal current detecting unit, decay frequency variation signal voltage detection unit are connected to respectively direct current decay frequency conversion source output terminal, and the electric current in the decay frequency variation signal that detects and voltage signal are inputed to described control collecting unit.
The signal output part of described control collecting unit is connected to the analysis expert system, and the control output end of described control collecting unit is connected to direct current decay frequency conversion source.
The utility model preferred embodiment is: described direct current decay frequency conversion source comprises constant-current source, gain control unit and the polarization converting unit that connects in turn; The control output end of collecting unit processed is connected to respectively described constant-current source, gain control unit and polarization converting unit.
In another embodiment, described direct current decay frequency conversion degaussing gear also further comprises AC signal source, alternating current detecting unit, alternating voltage detecting unit, measures output unit.The output control terminal of described control collecting unit is connected to described AC signal source, and the AC measurment signal of described AC signal source output is applied to the low-pressure end of described electric equipment by measuring output unit; Described alternating current detecting unit, alternating voltage detecting unit are connected to respectively the output in described AC signal source, and ac current signal and the ac voltage signal that detects inputed to described control collecting unit; Described control collecting unit inputs to the analysis expert system with measuring-signal.
In further preferred embodiment, direct current decay frequency conversion degaussing gear also comprises the human-computer dialogue unit, and described human-computer dialogue unit links to each other with described control collecting unit.
Described direct current decay frequency conversion degaussing gear also further comprises display unit and test report output unit; Described display unit, test report output unit all are connected to described analysis expert system.
Described direct current decay frequency conversion degaussing gear can further include power conversion unit, and its input is connected to AC220V, and output is connected to the power end of other unit in the degaussing gear.
The utlity model has following technique effect.
The utility model adopts the direct current decay frequency variation method technology of innovation, and the p-wire that its direct current decay frequency conversion source is exported by the demagnetization output unit by automatic gain control unit is connected to power transformer instrument transformer high-pressure side and is used for demagnetization work; The AC signal source is received power transformer instrument transformer low-pressure end through the p-wire of measuring output unit output and is used for measurement of residual magnetism work, each detecting unit sends signal to the control collecting unit by transducer, realize demagnetization and measurement of residual magnetism work by the analysis expert system, has the degaussing gear volume little, lightweight, the advantages such as demagnetization is thorough, and the erasing time is fast.
The utility model has overcome the deficiency of alternating current method, reached the interchange legal effect, and how much having done of remanent magnetism quantized metering, and can guarantee that the safety of the large perceptual electric equipment of the large capacity high voltage of electric power system and electrical network is normally moved, further improve national economic profit.
Description of drawings
Fig. 1 is the circuit structure block diagram of the utility model embodiment 1;
Fig. 2 is direct current decay frequency conversion source generating circuit structured flowchart among Fig. 1;
Fig. 3 is direct current decay frequency conversion source output current wave figure among Fig. 1;
Fig. 4 is the utility model degaussing process B-H figure;
Fig. 5 is the circuit structure block diagram of the utility model embodiment 2;
Fig. 6 is the circuit structure block diagram of the utility model embodiment 3;
Fig. 7 is that the utility model is for three-phase integrated demagnetization electric equipment field connection schematic diagram;
Fig. 8 is that the utility model is for single-phase monomer demagnetization electric equipment field connection schematic diagram.
Embodiment
Below in conjunction with drawings and the specific embodiments the utility model is described in further detail:
Embodiment 1: as shown in Figure 1, a kind of direct current decay frequency conversion degaussing gear comprises direct current decay frequency conversion source 8, control collecting unit 7, decay frequency variation signal current detecting unit 9, decay frequency variation signal voltage detection unit 10, demagnetization output unit 11.The output in described direct current decay frequency conversion source 8 links to each other with the input of demagnetization output unit 11, and the output of described demagnetization output unit 11 is connected to the high-pressure side of the electric equipment for the treatment of demagnetization; Described direct current decay frequency conversion source 8 is used for output direct current decay frequency conversion erase signal, is undertaken being connected to by the test specimen of demagnetization behind the over-current over-voltage protection by 11 pairs of direct current decay of demagnetization output unit frequency variation signal; Described decay frequency variation signal current detecting unit 9, decay frequency variation signal voltage detection unit 10 are respectively applied to detect electric current and the voltage signal in the direct current decay frequency variation signal of exporting in described direct current decay frequency conversion source 8, and the decay frequency variation signal electric current that detects and decay frequency variation signal voltage signal inputed to described control collecting unit 7, be used for providing a feedback signal to direct current decay frequency conversion source 8, guarantee that the direct current decay frequency conversion erase signal of exporting in direct current decay frequency conversion source 8 is normally stable, determine simultaneously the demagnetization progress.
Described control collecting unit 7 exports described decay frequency variation signal electric current and decay frequency variation signal voltage signal to analysis expert system 13, analysis expert system 13 by to the decay frequency variation signal electric current that collects, decay frequency variation signal voltage signal and the corresponding preset data that in device, arranges before treating the demagnetization of demagnetization electric equipment contrast, control and judgement demagnetization progress, if degaussing process finishes, it will automatically discharge and carry out measurement of residual magnetism work.
As shown in Figure 2, direct current decay frequency conversion source produces, and is to be selected the electric current output gear of constant-current source 15 by control collecting unit 7, and makes its periodic damping; The size of simultaneously ride gain control unit 16 gains of control collecting unit 7 is guaranteed the periodic damping of electric current output linearity; Control collecting unit 7 simultaneously also periodically switch polarity converting unit 17 make the erase signal of its output reach direct current decay frequency conversion effect, concrete waveform schematic diagram is as shown in Figure 3.
As shown in Figure 3, the utility model direct current decay frequency conversion source output current wave figure, the current waveform that the polarity that its generation selects the electric current of constant-current source 15 to export the size of gear, 16 gains of ride gain control unit, 17 outputs of switch polarity converting unit by control collecting unit 7 produces.
As shown in Figure 4, the B-H of the utility model degaussing process figure.It is by Fig. 3 erasing current waveform forming process corresponding the generation.Be not difficult to find out that from the B-H figure remanent magnetism is reduced near null value the most at last.This point can prove by measurement of residual magnetism.
Embodiment 2: as shown in Figure 5, direct current decay frequency conversion degaussing gear described in the utility model all elements in comprising embodiment 1, also further comprise AC signal source 2, alternating current detecting unit 3, alternating voltage detecting unit 4, measure output unit 5.
Described AC signal source 2 is by described control collecting unit 7 controls, for generation of the AC measurment signal, for the measurement of residual magnetism for the treatment of the demagnetization electric equipment provides signal source, the AC measurment signal of described AC signal source 2 outputs is applied to the low-pressure end of described electric equipment by measuring output unit 5.
Described alternating current detecting unit 3, alternating voltage detecting unit 4 are respectively applied to detect ac current signal and the ac voltage signal in the described AC measurment signal, and ac current signal and the ac voltage signal that detects inputed to described control collecting unit 7.
Described control collecting unit 7 inputs to analysis expert system 13 with measuring-signal, and the remanent magnetism amount of described electric equipment is calculated by described analysis expert system 13 according to the ac current signal that detects and ac voltage signal.
When the utility model device enters " measurement " state, it is the 400V AC measurment signal of 120 degree that control collecting unit 7 will be controlled AC signal source 2 outputs, three phase angle differences, for measurement of residual magnetism work provides signal source, at this moment alternating current detecting unit 3 and alternating voltage detecting unit 4 will be passed to detected current and voltage signals control collecting unit 7, the data that collect send to analysis expert system 13 after treatment, analysis expert system 13 contains by size and the harmonic wave that analysis draws no-load current, compare with our no-load current of artificial input again, and what of remanent magnetism the size of even-order harmonic component calculate, and the erasing current of pointing out us should select what gear carries out demagnetization work.
The foundation of the calculating of remanent magnetism has dual mode: the one, with the unloaded power supply of described ac voltage signal as simulation, the ratio size of calculating the theoretical value of no-load current of described ac voltage signal and described electric equipment or delivery test value is judged the size of remanent magnetism amount, described ratio is larger, and the remanent magnetism amount is larger.The 2nd, calculate the size that the proportionate relationship of even-order harmonic component and first-harmonic in described ac current signal or the ac voltage signal is judged the remanent magnetism amount, ratio is larger, and the remanent magnetism amount is larger.
Embodiment 3: as shown in Figure 6, direct current decay frequency conversion degaussing gear described in the utility model also further comprises power conversion unit 1, human-computer dialogue unit 6, display unit 12 and test report output unit 14 except comprising embodiment 2 described circuit structures.
Described power conversion unit 1 mainly is to convert AC220V to unit required various power supplys, guarantees other active cell normal operation; As :+5V direct-current power supply control collecting unit 7 and analysis expert system 13; + 12V direct-current power supply display unit 12 and test report output 14; ± 15V direct-current power supply detecting unit 3,4,9,10; ± 96V direct-current power supply direct current decay frequency conversion source 8; The 400V AC power is supplied with AC signal source 2.
Described human-computer dialogue unit 6 mainly is that people are to the operating units such as parameter setting, data input and order affirmation of the utility model device.
Described display unit 12 is mainly used to show that people are by the operated record in human-computer dialogue unit 6 and running and the result of the utility model device.
Described test report output unit 14 is that people can or print test report by the 6 operation outputs of human-computer dialogue unit after off-test.
At first convert AC220V to unit required various power supplys by power conversion unit 1, guarantee other active cell normal operation.(demagnetization work is carried out in demagnetization exactly in order to choose required operating state " demagnetization " state or " measurement " state as the people; Measurement is exactly that what of remanent magnetism measuring transformer exist).Processing is connected to measured test specimen (such as the low-pressure end of power transformer) through overcurrent-overvoltage with the AC measurment signal to measure output unit 5; Purpose is in order to detect no-load current and harmonic content, calculates what of its remanent magnetism by it; Demagnetization output unit 11 is decayed direct current and is connected to by the test specimen of demagnetization (such as the high-pressure side of power transformer) after frequency variation signal passes through the protections such as overcurrent relay and transient suppressor; Purpose is for giving by the erase signal of the best of test specimen of demagnetization.At first we select " measurement " state, at this moment control collecting unit 7 will be required by analysis expert system 13 no-load current of our input electric power transformer by display unit 12 prompting theoretical value or delivery test value, analysis expert system 13 will record and point out the measurement of residual magnetism work that enters like this.When device enters surveying work, it is the 400V AC measurment signal of 120 degree that control collecting unit 7 will be controlled AC signal source 2 outputs, three phase angle differences, for measurement of residual magnetism work provides signal source, at this moment alternating current detecting unit 3 and alternating voltage detecting unit 4 will be passed to detected current and voltage signals control collecting unit 7, the data that collect send to analysis expert system 13 after treatment, analysis expert system 13 contains by size and the harmonic wave that analysis draws no-load current, compare with our no-load current of artificial input again, and what of remanent magnetism the size of even-order harmonic component calculate, and the erasing current of pointing out us should select what gear carries out demagnetization work.Also can export Unit 14 output measurement report by test report.Control collecting unit 7 will be controlled direct current decay frequency conversion source 8 output direct current decay frequency conversion erase signals after device entered demagnetization work, and the erase signal waveform as shown in Figure 3.Decay frequency variation signal current detecting unit 9 and decay frequency variation signal voltage detection unit 10 will be passed to detected current and voltage signals control collecting unit 7 in degaussing process, the data that collect send to analysis expert system 13 after treatment, analysis expert system 13 is by the data analysis to collecting, and compare with the data that arrange that human-computer dialogue unit 6 is inputted, control and judgement demagnetization progress, if degaussing process finishes, it will automatically discharge and carry out measurement of residual magnetism work.It will we should select the erasing current of what gear to carry out next step demagnetization work by display unit 12 promptings analysis result behind the measurement of residual magnetism end-of-job, perhaps whether prompting exports test report, if need and to select Report Type by human-computer dialogue unit 6, export Unit 14 output measurement report by test report.
As shown in Figure 7, demagnetization electric equipment 19(is take three-phase transformer as example in three-phase integrated treating for the shown direct current of each embodiment of the utility model decay frequency conversion degaussing gear 18) in use field connection schematic diagram, for the high-tension demagnetization electric equipment 19 for the treatment of of three-phase integrated large capacity, be connected to low-pressure end a, b, the c that treats demagnetization electric equipment 19 with special connecting line with measuring output wiring terminal; The B phase that demagnetization electric equipment 19 high-pressure sides are received respectively at the two ends of demagnetization output and O be (high pressure tail) mutually.Can reach erasure effect fully like this, realize the demagnetization of three-phase with the time of the phase that disappears, thereby accomplish the effect of getting twice the result with half the effort.Further improved electrical production efficient.All wiring are disposable to be connected, and does not need thread-changing in demagnetization, measuring process.
As shown in Figure 8, the shown direct current of each embodiment of the utility model decay frequency conversion degaussing gear 18 treats that at single-phase monomer demagnetization electric equipment 20(is take single-phase transformer as example) use field connection schematic diagram, for the high-tension demagnetization electric equipment 20 for the treatment of of the large capacity of single-phase monomer, be connected to low-pressure end a, the x that treats demagnetization electric equipment 20 with special connecting line with measuring output wiring terminal a, b; The A phase X phase (high pressure tail) of demagnetization electric equipment 20 high-pressure sides is received respectively at the two ends of demagnetization output.All wiring are disposable to be connected, and does not need thread-changing in demagnetization, measuring process.
The validation verification of this device can be by a specific process AC signal to be made to be added to low-pressure side and to see that what of further affirmation remanent magnetism the size of no-load current of equipment under test and theoretical value or delivery test value compare.Also can compare with the AC erasing method maximum further checking to the dc erasing method.
Claims (6)
1. a direct current decay frequency conversion degaussing gear comprises direct current decay frequency conversion source (8), control collecting unit (7), decay frequency variation signal current detecting unit (9), decay frequency variation signal voltage detection unit (10), demagnetization output unit (11); It is characterized in that:
The output in described direct current decay frequency conversion source (8) links to each other with the input of demagnetization output unit (11), and the output of described demagnetization output unit (11) is connected to the high-pressure side of the electric equipment for the treatment of demagnetization;
Described decay frequency variation signal current detecting unit (9), decay frequency variation signal voltage detection unit (10) are connected to respectively direct current decay frequency conversion source (8) output, and decay frequency variation signal electric current and the decay frequency variation signal voltage signal that detects inputed to described control collecting unit (7);
The signal output part of described control collecting unit (7) is connected to analysis expert system (13), and the control output end of described control collecting unit (7) is connected to direct current decay frequency conversion source (8).
2. direct current according to claim 1 decay frequency conversion degaussing gear is characterized in that:
Described direct current decay frequency conversion source (8) comprises constant-current source (15), gain control unit (16) and the polarization converting unit (17) that connects in turn; The control output end of control collecting unit (7) is connected to respectively described constant-current source (15), gain control unit (16) and polarization converting unit (17).
3. direct current according to claim 1 and 2 decay frequency conversion degaussing gear is characterized in that:
Described direct current decay frequency conversion degaussing gear also further comprises AC signal source (2), alternating current detecting unit (3), alternating voltage detecting unit (4), measures output unit (5);
The output control terminal of described control collecting unit (7) is connected to described AC signal source (2), and the AC measurment signal of described AC signal source (2) output is applied to the low-pressure end of described electric equipment by measuring output unit (5);
Described alternating current detecting unit (3), alternating voltage detecting unit (4) are connected to respectively the output in described AC signal source, and ac current signal and the ac voltage signal that detects inputed to described control collecting unit (7);
Described control collecting unit (7) inputs to analysis expert system (13) with measuring-signal.
4. direct current according to claim 3 decay frequency conversion degaussing gear is characterized in that:
Described direct current decay frequency conversion degaussing gear also further comprises human-computer dialogue unit (6), and described human-computer dialogue unit (6) links to each other with described control collecting unit (7).
5. direct current according to claim 3 decay frequency conversion degaussing gear is characterized in that:
Described direct current decay frequency conversion degaussing gear also further comprises display unit (12) and test report output unit (14);
Described display unit (12), test report output unit (14) all are connected to described analysis expert system (13).
6. direct current according to claim 5 decay frequency conversion degaussing gear is characterized in that:
Described direct current decay frequency conversion degaussing gear also further comprises power conversion unit (1), and its input is connected to AC220V, and output is connected to the power end of other unit in the degaussing gear.
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201220454245 CN202749185U (en) | 2012-09-07 | 2012-09-07 | DC (direct current) attenuation frequency conversion demagnetization device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201220454245 CN202749185U (en) | 2012-09-07 | 2012-09-07 | DC (direct current) attenuation frequency conversion demagnetization device |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102800458A (en) * | 2012-09-07 | 2012-11-28 | 重庆旭辉电气有限公司 | Direct-current attenuation variable-frequency demagnetizing device |
| CN104833929A (en) * | 2015-04-30 | 2015-08-12 | 国网四川省电力公司电力科学研究院 | Transformer demagnetization analyzer |
| CN106019186A (en) * | 2016-06-03 | 2016-10-12 | 国网河北省电力公司电力科学研究院 | Transformer core residual magnetism detection method based on no-load current method |
-
2012
- 2012-09-07 CN CN 201220454245 patent/CN202749185U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102800458A (en) * | 2012-09-07 | 2012-11-28 | 重庆旭辉电气有限公司 | Direct-current attenuation variable-frequency demagnetizing device |
| CN104833929A (en) * | 2015-04-30 | 2015-08-12 | 国网四川省电力公司电力科学研究院 | Transformer demagnetization analyzer |
| CN106019186A (en) * | 2016-06-03 | 2016-10-12 | 国网河北省电力公司电力科学研究院 | Transformer core residual magnetism detection method based on no-load current method |
| CN106019186B (en) * | 2016-06-03 | 2019-11-05 | 国网河北省电力公司电力科学研究院 | A kind of transformer core remanent magnetism detection method based on no-load current method |
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Effective date of registration: 20151028 Address after: 710043 Shaanxi province Xi'an new City Town Industrial Park of Dongxing science and Technology Building 7 room 4 Patentee after: XI'AN XU&HUI ELECTROMECHANICAL TECHNOLOGY CO., LTD. Address before: 401120, Chongqing new North Zone and 48 Lok Lok Avenue, building 1, 22-9 Patentee before: Chongqing Xu Hui Electric Co., Ltd. |
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