CN204188674U - A kind of local discharge superhigh frequency signal imitation source - Google Patents
A kind of local discharge superhigh frequency signal imitation source Download PDFInfo
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- CN204188674U CN204188674U CN201420613831.1U CN201420613831U CN204188674U CN 204188674 U CN204188674 U CN 204188674U CN 201420613831 U CN201420613831 U CN 201420613831U CN 204188674 U CN204188674 U CN 204188674U
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 12
- 230000003321 amplification Effects 0.000 claims abstract description 11
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 11
- 229910052742 iron Inorganic materials 0.000 claims abstract description 6
- 230000007547 defect Effects 0.000 description 28
- 238000000034 method Methods 0.000 description 15
- 238000009413 insulation Methods 0.000 description 11
- 238000010586 diagram Methods 0.000 description 9
- 238000002474 experimental method Methods 0.000 description 8
- 239000012212 insulator Substances 0.000 description 8
- 239000002923 metal particle Substances 0.000 description 7
- 238000001514 detection method Methods 0.000 description 6
- 239000004020 conductor Substances 0.000 description 5
- 230000001105 regulatory effect Effects 0.000 description 5
- 238000004088 simulation Methods 0.000 description 5
- 239000011800 void material Substances 0.000 description 5
- 239000000356 contaminant Substances 0.000 description 4
- 238000012544 monitoring process Methods 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 230000032683 aging Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000003491 array Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 230000005670 electromagnetic radiation Effects 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N ferric oxide Chemical compound O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000009533 lab test Methods 0.000 description 1
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 1
- 238000004020 luminiscence type Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000033772 system development Effects 0.000 description 1
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Abstract
A kind of local discharge superhigh frequency signal imitation source, comprise and be installed in shielding iron case, the USB module (1) connected successively, the high frequency sinusoidal signal generator (2) that Frequency Adjustable is selected, signal madulation module (3), signal amplification module (4) and emitting antenna (5), described USB module also directly exports envelope signal to signal madulation module (3), zero-crossing comparator (6) is separately had to input the signal of the first mutual inductor (8) or the second mutual inductor (9) through single-pole double-throw switch (SPDT) (7), first mutual inductor (8) or the second mutual inductor (9) external 60V and 220V civil power respectively, also have the power supply (10) of external 220V civil power to each module for power supply, emitting antenna (5) exports various shelf depreciation UHF signal.The utility model is with a wide range of applications and be combined closely with engineering, can Simulated GlS, shelf depreciation dissimilar in transformer UHF signal, the signal accuracy of generation is high, and apparatus structure is simple, convenient operation.
Description
Technical field
The utility model relates to a kind of local discharge superhigh frequency (UHF) signal imitation source.
Background technology
At present, China's power system development speed is constantly accelerated, also more and more higher to the requirement of the safety and reliability of system cloud gray model.Because the harmfulness of large scale electrical power unit accident is huge, sudden power outage can cause huge economic loss and bad social influence.A large amount of fault statistics analysis shows, insulation fault is the main cause that large scale electrical power unit produces fault, and shelf depreciation (PD) causes one of insulation fault and aging most important reason.
Shelf depreciation is under high electric field intensity, the electric discharge phenomena that electrical strength lower position occurs in insulator.Various electrical phenomena can be produced in shelf depreciation process, as electric pulse, electromagnetic radiation, and be attended by the transfer of electric charge and the loss of electric energy, also can produce the information of various non-electrical simultaneously, as produced sound wave, luminescence, heating and producing some new products.The power equipment such as GIS, transformer Partial Discharge Detection is divided into electrical measuring method and non-electrical measuring method by the physical quantity character detected, comprise the detection methods such as pulse current method, ultrasonic Detection Method, light detection method, chemical measure, very high frequency(VHF) method, ultrahigh frequency method, these detection methods all respectively have its relative merits, also obtain application in various degree at the scene.Wherein ultrahigh frequency method (UHF method) is as a kind of new method of Partial Discharge Detection, because it has traditional electrical measuring method and other non-electrical measuring methods not to have series of advantages, is a kind of very promising method of monitoring shelf depreciation of current on-line monitoring.
Different power equipment causes the reason of PD to be not quite similar, and its PD defect produced is also different, and the physical model of same device interior PD defect is also different.Such as just can be divided into the large class of high-pressure conductor metallic projections defect, free metal particle defects, insulating surface fixing metal particle defects, void defects four for GIS PD; Transformer PD has oil clearance electric discharge in oil-barrier insulation in the middle part of winding; Winding overhang oil clearance discharges; The oil clearance electric discharge of contact insulated conductor and insulating paper (lead wire insulation, overlap joint insulation); Shelf depreciation in the paper oil insulations such as lead-in wire, overlap joint line; Between coil, the oil clearance of (minor insulation) discharges; Turn-to-turn insulation partial breakdown; Insulating paper is along seven classes such as face gliding spark discharges.
When studying all kinds of PD defect by UHF method, outside the experiment of removing device context, a large amount of simulated experiment must be carried out, different its Partial discharge signals of PD defect is not quite similar, rise time of the pulse current produced when their offices put, duration of pulse different, the UHF signal excited by pulse current also has larger difference in waveform, time domain distribution etc., needs to set up different physical models to different PD defects.Although the UHF signal type that different insulation defects excites when there is PD is different, for same defect, its UHF signal has statistical law, and especially in power frequency period, it can present specific time domain, frequency domain distribution characteristic.And UHF method is before practice to on-line monitoring system, a series of simulated experiment must be carried out in laboratory or scene, the various performances of test type UHF sensor.Therefore can the real various PD UHF signal of approximate simulation by research UHF signal imitation source.
Because local discharge superhigh frequency signal frequency is at 0.3-3GHz, its simulation signal generator must be impulse source, according to consulted document, at present not for the UHF signal source of certain single shelf depreciation, the signal source of current existence is the impulse source for simple ultra-high frequency signal, can only simulate the signal of the steepness (rising, negative edge) with UHF signal, single UHF signal pulsewidth.But the frequency of its simulating signal produced, amplitude all can not regulate, and also do not possess the power frequency characteristic of PD.And general shelf depreciation all occurs under electric system power-frequency voltage, the UHF signal that therefore dissimilar PD excites has specific operating frequency phase characteristic, these power frequencies for analyze PD type, quantitatively, the research such as developing stage is all very important.
Therefore, study a kind of shelf depreciation UHF signal imitation source, can the UHF signal of the different shelf depreciation pattern such as Simulated GlS, transformer, so will the carrying out smoothly of very convenient all kinds of UHF simulated experiment, but the not special simulation signal generator for all kinds of shelf depreciation pattern at present.
Utility model content
Technical problem to be solved in the utility model, just be to provide a kind of local discharge superhigh frequency signal imitation source, this dummy source can be simulated and be produced GIS, the different shelf depreciation pattern of the power equipments such as transformer: metallic projections defect, free metal particle defects, insulator surface metallic contaminant and the UHF signal ejected during void defects generation shelf depreciation between insulator and high-pressure conductor, and the frequency analog signal produced is adjustable, power adjustable, umber of pulse is adjustable, not only comprise the uhf electromagnetic wave signal of 0.3-1.5GHz, and signal has the distribution character of shelf depreciation at a power frequency period.
Solve the problems of the technologies described above, the technical solution adopted in the utility model is:
A kind of local discharge superhigh frequency signal imitation source, it is characterized in that: comprise and be installed in shielding iron case, the USB module 1 connected successively, the high frequency sinusoidal signal generator 2 that Frequency Adjustable is selected, signal madulation module 3, signal amplification module 4 and emitting antenna 5, described USB module also directly exports envelope signal to signal madulation module 3, zero-crossing comparator 6 is separately had to input the signal of the first mutual inductor 8 or the second mutual inductor 9 through single-pole double-throw switch (SPDT) 7, first mutual inductor 8 or the second mutual inductor 9 external 60V and 220V civil power respectively, also have the power supply 10 of external 220V civil power to each module for power supply, emitting antenna 5 exports various shelf depreciation UHF signal.
Described signal madulation module is multiplier module, and the high frequency sinusoidal signal generator mode of frequency regulation that described Frequency Adjustable is selected is that knob controls or voltage-controlled mode, and described antenna is broadband omnidirectional antenna.
The high frequency sinusoidal signal generator 2 that described Frequency Adjustable is selected is by tuning frequency button 11 frequency modulation, signal amplification module 4 by power regulating knob 12 regulating power.
The principle of work process of this signal source:
1) sampled data of the power frequency envelope needed for different shelf depreciation type is obtained, and be stored in USB with the form of array, here power frequency envelope is by carrying out a large amount of field experiment and laboratory experiment obtains real shelf depreciation UHF signal, then by software process, the array of txt form is become by the UHF signal-data processing obtained to deposit in the hard disk of computer, these arrays are named successively according to PD type, can be transferred easily by Labview software;
2) to the power frequency envelope that USB module produces, what this signal source adopted is the mode that software and hardware combines, the generation of power frequency envelope is also software and hardware combining composition virtual instrument, wherein software adopts Labview2012, hardware is then USB module, and what send is the envelope of txt form stored; The high frequency sinusoidal signal input signal multiplier module that the envelope of local discharge signal and high frequency sinusoidal generator produce, is multiplied two paths of signals;
3) digital signal after being multiplied inputs to signal amplification module, enters amplification, filtering;
4) signal after amplifying exports emitting antenna to through cable, thus exports the ultrahigh frequency simulating signal under shelf depreciation different mode.
Described USB module is except producing power frequency envelope, it also has the function controlling the high frequency sinusoidal signal frequency that high frequency sinusoidal generator produces concurrently, knob is adopted to control or voltage-controlled mode, this makes easy and simple to handle, accurately, and the frequency range of UHF signal is 300MHz-3GMz, and this signal comprises power frequency reference information, and its amplitude, frequency, pulse number are adjustable.
Because simulated local discharge signal pattern is various, the frequency range of signal is 300MHz-3GHz, and amplitude, the power of signal also change to some extent, and this just requires that emitting antenna has good bandwidth, gain and radiation efficiency etc., therefore select the broadband omnidirectional antenna that can meet the demands as emitting antenna.
Signal source is controlled by computer (USB module), and all hardware equipment is all contained in iron case, and manual operation computer just can produce required shelf depreciation and excite UHF simulating signal, tests.
Beneficial effect: the utility model is controlled by USB module, the envelope of various Partial Discharge UHF signal is multiplied in signal madulation module with high frequency sinusoidal signal, the waveform obtained exports through antenna after amplification, filtering, can simulate the shelf depreciation UHF signal of various different mode more really; The utility model is with a wide range of applications and be combined closely with engineering, can Simulated GlS, shelf depreciation dissimilar in transformer UHF signal, the signal accuracy of generation is high, and apparatus structure is simple, convenient operation.
Accompanying drawing explanation
Below in conjunction with accompanying drawing, the utility model is described in further detail.
Fig. 1 is shelf depreciation UHF signal imitation source of the present utility model composition and annexation schematic diagram;
Fig. 2 a is the UHF signal schematic representation of the metallic projections defect PD waveform 0-2000ns that the utility model exports;
Fig. 2 b is the UHF signal schematic representation of the metallic projections defect PD waveform 0-900ns that the utility model exports;
Fig. 3 a is the UHF signal schematic representation of the free metal particle defects PD waveform 0-500ns that the utility model exports;
Fig. 3 b is the UHF signal schematic representation of the free metal particle defects PD waveform 0-200ns that the utility model exports;
Fig. 4 is the insulator surface metallic contaminant PD waveform schematic diagram that the utility model exports;
Fig. 5 is void defects PD waveform schematic diagram between the insulator of the utility model output and high-pressure conductor;
The theoretical fitting waveform schematic diagram of Fig. 6 a corresponding to metallic projections defect;
The theoretical fitting waveform schematic diagram of Fig. 6 b corresponding to free metal particle defects;
The theoretical fitting waveform schematic diagram of Fig. 6 c corresponding to insulator surface metallic contaminant;
Fig. 6 d is the theoretical fitting waveform schematic diagram between insulator and high-pressure conductor corresponding to void defects.
In figure: 1-USB module, the high frequency sinusoidal signal generator that 2-Frequency Adjustable is selected, 3-signal madulation module, 4-signal amplification module, 5-emitting antenna, 6-zero-crossing comparator, 7-single-pole double-throw switch (SPDT), 8--first mutual inductor, 9-second mutual inductor, 10-power supply, 11-tunes button frequently, 12-power regulating knob.
What the difference of Fig. 2 a and Fig. 2 b was that Fig. 2 a records is the UHF signal of 0-2000ns, what Fig. 2 b recorded is the UHF signal of 0-900ns, and the length of the signal recorded is different, and 2b is equivalent to launch 2a, more can see its details, if do not need one of them can be deleted.The situation of Fig. 3 a and Fig. 3 b is similar.
Embodiment
See Fig. 1, the local discharge superhigh frequency signal imitation source of shelf depreciation UHF signal imitation source of the present utility model embodiment, comprise and be installed in shielding iron case, the USB module 1 connected successively, the high frequency sinusoidal signal generator 2 that Frequency Adjustable is selected, signal madulation module 3, signal amplification module 4 and wideband omni-directional emitting antenna 5, USB module 1 also directly exports envelope signal to signal madulation module 3, zero-crossing comparator 6 is separately had to input the signal of the first mutual inductor 8 or the second mutual inductor 9 through single-pole double-throw switch (SPDT) 7, first mutual inductor 8 and the second mutual inductor 9 external 60V and 220V civil power respectively, also have the power supply 10 of external 220V civil power to each module for power supply, wideband omni-directional emitting antenna 5 exports various shelf depreciation UHF signal, signal madulation module is multiplier module, and the high frequency sinusoidal signal generator 2 that Frequency Adjustable is selected is by tuning frequency button 11 frequency modulation, signal amplification module 4 by power regulating knob 12 regulating power.
The high frequency sinusoidal signal generator mode of frequency regulation that Frequency Adjustable is selected also can select voltage-controlled mode.
Wherein USB module adopts the NI USB-6211 module of NI company, and mutual inductor is voltage transformer (VT), by the power frequency ac voltage signal of 60V/220V by the AC signal for 5V, has matured product.
High frequency sinusoidal signal generator, signal madulation module, signal amplification module, emitting antenna are all prior aries.Antenna is mainly launched in order to transmitting situation simulation being produced the closely possible Reality simulation PD of wide band UHF signal, needs broadband omni-directional antenna.
The envelope that USB module produces exports modulation module to by cable, and the high frequency sinusoidal signal of high frequency signal generator also reaches modulation module by cable, and this two paths of signals is transferred to antenna transmission through the multiplier signal obtained that is multiplied through multiplying arrangement.In addition, there is error in discharge waveform envelope cycle and the power frequency period of actual output, if export discharge waveform envelope continuously, error will add up, arrange so devise to trigger, be exactly the zero-crossing comparator in Fig. 1, reset during to realize power frequency reference voltage zero passage.
Application example
Four kinds of typical shelf depreciation UHF signal imitation source experiments in GIS:
Fig. 2 to Fig. 5 is the signal measured waveform launched with this shelf depreciation UHF signal imitation source.
In experiment, this dummy source is contained in have carried out, in the iron case of shielding processing, so can reducing the error of experiment.The physical model of the insulation defect of current GIS device there is no unified standard, and the model selected by this dummy source is domestic scholars research GIS partial discharge four kinds of models at most used, and they can reflect various insulation defects existing in GIS device substantially.
The source signal waveform table of four kinds of typical defects reveals very different characteristics, analyze from Fig. 2 to Fig. 5, the rise time (or fall time of negative pulse) of the source signal waveform of metallic projections defect, all signals were individual pulse signal usually between 1 ~ 2ns; The source signal rise time of free metal particle defects is many at below 1ns, and the signal of more generally 2 ~ 3 superimposed pulses; The source signal rise time of insulator surface metallic contaminant and fall time all greatly extend, and the rise time reaches more than 8ns usually, then reach tens even tens ns fall time; Void defects institute active signal is the signal that dipulse is formed by stacking, and the rise time is longer equally, usually between 5 ~ 10ns.In the GIS that this and current Chinese scholars expert obtain, the UHF signal of shelf depreciation has good similarity.
The theoretical fitting waveform schematic diagram of Fig. 6 a to Fig. 6 c corresponding to four kinds of typical PD waveforms of actual measurement, comparison diagram 2 to Fig. 5, the waveform that the utility model obtains and theoretical fitting waveform comparison coincide.
Claims (2)
1. a local discharge superhigh frequency signal imitation source, it is characterized in that: comprise and be installed in shielding iron case, the USB module (1) connected successively, the high frequency sinusoidal signal generator (2) that Frequency Adjustable is selected, signal madulation module (3), signal amplification module (4) and emitting antenna (5), described USB module also directly exports envelope signal to signal madulation module (3), zero-crossing comparator (6) is separately had to input the signal of the first mutual inductor (8) or the second mutual inductor (9) through single-pole double-throw switch (SPDT) (7), first mutual inductor (8) or the second mutual inductor (9) external 60V and 220V civil power respectively, also have the power supply (10) of external 220V civil power to each module for power supply, emitting antenna (5) exports various shelf depreciation UHF signal.
2. local discharge superhigh frequency signal imitation source according to claim 1, it is characterized in that: described signal madulation module is multiplier module, the high frequency sinusoidal signal generator mode of frequency regulation that described Frequency Adjustable is selected is that knob controls or voltage-controlled mode, and described antenna is broadband omnidirectional antenna.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104330599A (en) * | 2014-10-22 | 2015-02-04 | 广东电网有限责任公司电力科学研究院 | Partial-discharge ultrahigh-frequency signal simulation source |
| CN105372568A (en) * | 2015-12-04 | 2016-03-02 | 国网浙江省电力公司电力科学研究院 | Ultrasonic wave generation system and ultrasonic excitation signal generation method |
| CN106556784A (en) * | 2017-01-23 | 2017-04-05 | 贵州电网有限责任公司电力科学研究院 | A kind of method and device for simulating different degrees of GIS Partial discharge signals |
| CN106771932A (en) * | 2017-01-23 | 2017-05-31 | 贵州电网有限责任公司电力科学研究院 | A kind of method of GIS partial discharge signal source and simulation shelf depreciation |
| CN107067859A (en) * | 2017-02-14 | 2017-08-18 | 吴笃贵 | Partial Discharge Detection stimulating and training system |
-
2014
- 2014-10-22 CN CN201420613831.1U patent/CN204188674U/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104330599A (en) * | 2014-10-22 | 2015-02-04 | 广东电网有限责任公司电力科学研究院 | Partial-discharge ultrahigh-frequency signal simulation source |
| CN104330599B (en) * | 2014-10-22 | 2017-05-03 | 广东电网有限责任公司电力科学研究院 | Partial-discharge ultrahigh-frequency signal simulation source |
| CN105372568A (en) * | 2015-12-04 | 2016-03-02 | 国网浙江省电力公司电力科学研究院 | Ultrasonic wave generation system and ultrasonic excitation signal generation method |
| CN106556784A (en) * | 2017-01-23 | 2017-04-05 | 贵州电网有限责任公司电力科学研究院 | A kind of method and device for simulating different degrees of GIS Partial discharge signals |
| CN106771932A (en) * | 2017-01-23 | 2017-05-31 | 贵州电网有限责任公司电力科学研究院 | A kind of method of GIS partial discharge signal source and simulation shelf depreciation |
| CN107067859A (en) * | 2017-02-14 | 2017-08-18 | 吴笃贵 | Partial Discharge Detection stimulating and training system |
| CN107067859B (en) * | 2017-02-14 | 2019-03-22 | 吴笃贵 | Partial Discharge Detection stimulating and training system |
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