CN106610464A - System and method for judging frequency selection filtering performance of transformer winding deformation tester - Google Patents
System and method for judging frequency selection filtering performance of transformer winding deformation tester Download PDFInfo
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- CN106610464A CN106610464A CN201611040220.2A CN201611040220A CN106610464A CN 106610464 A CN106610464 A CN 106610464A CN 201611040220 A CN201611040220 A CN 201611040220A CN 106610464 A CN106610464 A CN 106610464A
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- frequency
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- transformer winding
- deformation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/72—Testing of electric windings
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/16—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring the deformation in a solid, e.g. by resistance strain gauge
Abstract
The invention discloses a system and method for judging the frequency selection filtering performance of a transformer winding deformation tester, and the system comprises a signal generator which outputs a sine interference signal with the known frequency and amplitude value; an adder which carries out the adding of an output signal of a tester which is in a single-frequency-point detection mode and is used for a sine signal with the known frequency, and an output signal of the signal generator; an attenuator which carries out the attenuation of the output signal of the adder, and transmits the attenuation signal to a response signal detection port of the tester. The system enables the frequency selection filtering band attenuation requirements to be changed into gain requirements, carries out the comprehensive determination of the frequency selection filtering characteristics through a detection result of the tester, and indirectly represents the quality of the frequency selection filtering characteristics of the filter through an error value of gain detection, so as to solve a problem that a conventional system needs to disassemble or damage a tester during the detection of the frequency selection filtering performances.
Description
Technical field
The present invention relates to transformer fault detection field, and in particular to a kind of to judge deformation of transformer winding tester frequency-selecting
The method of filtering performance.
Background technology
Transformator is the nucleus equipment of electrical network, and winding deformation is one of modal internal fault of power transformer, in electricity
In the presence of power and mechanical force, there is irreversible change in the size of winding or shape, after winding is locally deformed with, even if
Do not damage immediately, it is also possible to leave serious potential faults.《Prevent 25 emphasis of power generation major accident from wanting
Ask》With《The great anti-accident measures of 18 electrical networks of State Grid Corporation of China》Deformation test of transformer winding is placed on highly important
Position, it is stipulated that method of frequency response method test winding deformation is the pilot project that 110 (66) kV and above transformator must be carried out.Actively develop
Deformation of transformer winding diagnostic work, finds the transformator for having winding deformation potential faults in time, and in a planned way carries out hanging cover
Check and overhaul, can not only save substantial amounts of human and material resources, the generation to preventing Accident of Transformer also has and its important work
With.
It is that deformation of transformer winding is tested, each power generation unit is generally using based on frequency response analysis
The deformation of transformer winding tester (hereinafter referred to as tester) of (Frequency Response Analysis, FRI).Frequency
Response analyses method is the method for test winding deformation conventional both at home and abroad, and equivalent circuit of transformator is considered as the two of common ground for which
Port network, after winding deformation, inner parameter change will cause transmission function to change, by analyzing and comparing transformator
Frequency response characteristic, it can be found that whether Transformer Winding deforms [9-10].
As shown in figure 1, wherein, it is sound for pumping signal detection port, V2 that Vs is sinusoidal signal output port, V to tester
Induction signal detects port；Possesses the independent signal detection interface of a sine wave exciting signal output interface and two, as one
Test instrunment is planted, its current techique part should meet《GB/T 6587-2012 electronic measuring instrument general specifications》Requirement.For
Meet on-the-spot test, reduce impact of other frequency signals to test result, its capacity of resisting disturbance, i.e. frequency-selective filtering performance, i.e.,
The ability of the interference signal in addition to swept-frequency signal is filtered, is required as the basic function of tester, in power industry standard
《The frequency response analysis method of DL/T911-2004 winding deformation of power transformer》Although in it has been already mentioned that but lack it is corresponding
Calibration steps carries out the assessment and judgement of science to the performance indications.
For discriminating test instrument frequency-selective filtering performance, typically tested using spectrum analyzer, however, tester frequency sweep letter
Number output and response signal detection are integrated in instrument internal, the performance of filter test needs of response signal test side disassemble or
Destruction tester.Therefore a kind of more effective, direct decision method of research is needed, to frequency-selective filtering when being easy to tester to calibrate
Characteristic is judged.
The content of the invention
The present invention provides a kind of judgement deformation of transformer winding tester frequency-selective filtering to solve above-mentioned technical problem
The system and method for energy.
The present invention is achieved through the following technical solutions：
A kind of system for judging deformation of transformer winding tester frequency-selective filtering performance, including：
Signal generator, exports the sinusoidal interference signal of given frequency and amplitude；
Adder, output signal to the tester in single-frequency point detection pattern and Gaster Sus domestica fixed frequency sinusoidal signal and
The output signal of signal generator is added；
Attenuator, decays to the output signal of adder, and deamplification is sent to the response signal of tester
Detection port.
Impact of the interference signal of this programme to tester is mainly interfered to the amplitude of pumping signal output, makes sound
The sinusoidal signal virtual value of induction signal detection port changes, and affects the accuracy of gain detection.Its basic ideas is to mark
The accurate band attenuation for proposing requires to be converted into gain requirement, carries out synthesis to frequency-selective filtering characteristic using the testing result of tester
Judge, the error amount secondary indication tester frequency-selective filtering characteristic quality degree detected using gain.Can be avoided using this device
Disassembling or destroying to tester, meets on-the-spot test and calibration, meets the operation principle of instrument.
Preferably, also including for showing for being detected to the signal amplitude and frequency of two inputs of signal generator
Ripple device.Oscillograph can show the amplitude and frequency size of tester output drive signal, and be based on this amplitude and frequency regulation
The signal amplitude and frequency of function signal generator output, it is ensured that the signal during frequency-selective filtering performance judgment will not occur
Change.
Preferably, the amplitude operational linearity of the adder is less than 1%.Adder is used for function signal generator
The pumping signal linear, additive of output signal and tester, is the accuracy for ensureing this test system, and the amplitude of adder is linear
Degree must be higher, theoretical maximum deviation of the operational linearity less than 1%, i.e. measurement pointExample
Such as, when maximum output voltage is 20V, measurement point maximum deviation<0.2V, it is ensured that the accuracy of test system result of determination.
A kind of method for judging deformation of transformer winding tester frequency-selective filtering performance, it is characterised in that including following step
Suddenly：
A, deformation of transformer winding tester output sinusoidal signal V1T (), its rate of scanning are f0, amplitude is A, and phase place isSignal source exports sinusoidal signal V2T (), its frequency are kf0, amplitude is α A, and phase place is
B, to V1(t) and V2T () carries out in-phase proportion addition and obtains V (t)；
C, attenuation operations are carried out to V (t) and the signal V after being decayedδ(t) send the signal to Transformer Winding
The response signal detection port of deformation tester；
D, deformation of transformer winding tester output signal are Vout(t), and calculate frequency sweep gain；
E, frequency sweep gain and standard setting △ δ are compared to judge deformation of transformer winding tester frequency-selective filtering
Performance.
The result of frequency-selective filtering performance judgment represented using detection gain error absolute value, detection error absolute value and letter
Number source output signal amplitude is relevant with the attenuation quotient that deformation of transformer winding tester is required, when function signal generator is exported
When signal amplitude is α times of deformation of transformer winding tester excitation signal amplitude, and require deformation of transformer winding tester
Frequency-selective filtering coefficient be β when, detection gain error expression formula be
When signal source output signal amplitude is identical with deformation of transformer winding tester excitation signal amplitude, and require to become
When the frequency-selective filtering coefficient of deformation of transformer winding tester is 0.5, deformation of transformer winding tester frequency-selective filtering Judging index
For △ δ≤0.9691.
Preferably, in step E, the deformation of transformer winding test when frequency sweep gain is less than or equal to standard setting △ δ
Instrument frequency-selective filtering performance meets the requirements.
Preferably, the V1T the rate of scanning of () is f0Less than or equal to 600kHz.
The present invention compared with prior art, at least has the following advantages and advantages：
Band attenuation is required to be converted into gain requirement by this method, is tested come indirect judgement using the absolute error value of gain
The frequency-selective filtering performance of instrument, carries out synthetic determination to frequency-selective filtering characteristic using the testing result of tester, without the need for dismounting test
Frequency-selecting filter inside instrument, meets on-the-spot test and calibration, meets the operation principle of instrument.
Description of the drawings
Accompanying drawing described herein is used for providing further understanding the embodiment of the present invention, constitutes of the application
Point, do not constitute the restriction to the embodiment of the present invention.In the accompanying drawings：
Fig. 1 is the schematic diagram of the system of the present invention.
Fig. 2 is that this test data draws broken line graph.
Specific embodiment
To make the object, technical solutions and advantages of the present invention become more apparent, with reference to embodiment and accompanying drawing, to this
Invention is described in further detail, and the exemplary embodiment of the present invention and its explanation are only used for explaining the present invention, do not make
For limitation of the invention.
This patent is carried out the frequency-selective filtering performance test to deformation of transformer winding tester and is studied, Main Basiss《DL/
The frequency response analysis method of T911-2004 winding deformation of power transformer》And its 2016 requirement of the revised edition to performance indications,
The decision method for frequency-selective filtering experimental performance index is proposed, and the deformation of transformer winding tester to main flow producer is selected
Frequency filtering performance is tested.Test is judged by carrying out Sichuan Electric Power production unit deformation of transformer winding test instrunment scene
Work with performance evaluation, it was confirmed that the method for proposition is reliable, meet the working condition of tester reality.Finally to improving tester
Frequency-selective filtering performance propose suggestion.
Embodiment
A kind of system for judging deformation of transformer winding tester frequency-selective filtering performance, including signal as shown in Figure 1 occurs
The attenuator of device, adder and standard；Signal generator exports the sinusoidal interference signal of given frequency and amplitude；Adder is to place
In single-frequency point detection pattern and the output signal and signal generator of the tester of Gaster Sus domestica fixed frequency sinusoidal signal output letter
Number it is added；Attenuator is decayed to the output signal of adder, and deamplification is sent to the response letter of tester
Number detection port.
Also include the oscillograph for being detected to the signal amplitude and frequency of two inputs of signal generator.
The amplitude operational linearity of the adder is less than 1%.
For said apparatus, its judge the method for frequency-selective filtering performance as：It is a kind of to judge deformation of transformer winding tester
The method of frequency-selective filtering performance, it is characterised in that comprise the following steps：
A, deformation of transformer winding tester output sinusoidal signal V1T (), its rate of scanning are f0, amplitude is A, and phase place isSignal source exports sinusoidal signal V2T (), its frequency are kf0, amplitude is α A, and phase place is
B, to V1(t) and V2T () carries out in-phase proportion addition and obtains V (t)；
C, attenuation operations are carried out to V (t) and the signal V after being decayedδ(t) send the signal to Transformer Winding
The response signal detection port of deformation tester；
D, deformation of transformer winding tester output signal are Vout(t), and calculate frequency sweep gain；
E, frequency sweep gain and standard setting △ δ are compared to judge deformation of transformer winding tester frequency-selective filtering
Performance.
By taking a specific embodiment as an example：
If deformation of transformer winding tester exports sinusoidal signal V1T the frequency of () is f0, amplitude is A, and phase place isLetter
Number source output sinusoidal signal V2T (), used as interference signal, frequency is k times of signal V1The frequency of (t), i.e. k f0, amplitude believed for α times
Number V1T the amplitude of (), i.e. α A, phase place are set toThen there is formula (1)：
Adder is to V1(t) and V2T () carries out in-phase proportion addition and obtains V (t), if proportionality coefficient is 1, through adder
Signal V (t) afterwards is：
V (t)=V1(t)+V2(t)；
Attenuation operations are carried out to V (t) and the signal V after being decayedδ(t) send the signal to Transformer Winding change
Shape tester response signal detection port, if the attenuation of attenuator be δ dB, i.e., signal amplitude decay input signal 10δ/20Times, then the signal V after standard attenuatorδT () is：
To input signal in frequency f inside deformation of transformer winding tester0Place, can be to except f with frequency-selective filtering function0
Signal amplitude decay in addition.The input signal of deformation of transformer winding tester response signal detection port is Vδ(t), if transformation
Device winding deformation tester frequency-selecting filter is k times of f to frequency0The interference signal amplitude attenuation of input is β times, then through transformation
Signal V after device winding deformation tester frequency-selective filteringoutT () is：
Wherein, φ2For phase shifting angle of the wave filter to interference signal, tester calculating frequency sweep gain A m
Wherein VoutAnd VinFor the root-mean-square value of sinusoidal signal：
Frequency sweep gain A m is compared to judge deformation of transformer winding tester frequency-selective filtering with standard setting △ δ
Performance.
Using detection gain absolute error value judge, therefore, Judging index with test when standard attenuator occurrence without
Close, specific attenuator need not be selected at the trial, but its attenuation should be known.
According to requirement of the standard to frequency-selective filtering performance, its -6dB bandwidth should be less than the 2% of rate of scanning, i.e. transformator around
The frequency-selective filtering function of group deformation tester at least should decay to the signal at output sinusoidal frequency value ± 2% for detecting
For 1/2nd of the signal open width value.So standard setting theory is：
I.e.
When frequency-selective filtering performance is represented with absolute error, due to external standard attenuator attenuation δ, it is known that so：
Knowable to above formula, the factor for affecting frequency-selective filtering performance indications is amplitude times of the external interference signals to pumping signal
The number attenuation multiple β of α and wave filter itself to interference signal.As requested, deformation of transformer winding tester is to detecting
The signal exported at sinusoidal frequency value positioned at (1 ± 2%) times should at least decay to 1/2nd of the signal open width value, i.e. and β≤
0.5, the amplitude that input nonlinearities signal is set during verification is identical with test signal, i.e. α=1, it can be deduced that the index for judging as：
Therefore, the index of frequency-selective filtering calibration is in this case：
|△δ|≤0.9691dB。
Following table is given under the conditions of α=1, the calibration theory calls under different frequency-selective filtering decay indices.
In order to verify to the correctness of above-mentioned decision method, two be generally equipped with from current domestic each electric power enterprise
Plant deformation of transformer winding tester to be verified, tested according to the following steps：
1) deformation of transformer winding tester is set to single-frequency point Scanning Detction pattern, and rate of scanning Fo is respectively set to
1kHz、10kHz、100kHz、500kHz、1000kHz；
2) digital oscilloscope measures the signal amplitude and frequency of two inputs of adder calculator simultaneously；
3) signal generator output sinusoidal signal, frequency are respectively set to 0.98Fo and 1.02Fo, arrange output amplitude with
Deformation of transformer winding tester sine wave output signal amplitude is identical；
4) adder is built by broadband operational amplifier, and amplitude operational linearity is preferably better than 1%, for transformator
Winding deformation tester carries out in-phase proportion with the sine wave signal that signal generator is exported and is added, and proportionality coefficient is taken as 1；
5) attenuation of selection standard attenuator is -20dB；
6) during deformation of transformer winding tester carries out single-frequency point Scanning Detction with frequency Fo, record applies respectively
Frequency sweep gain detection data when frequency is 0.98Fo and 1.02Fo sine wave signals.
As shown in table 2, it is as shown in Figure 2 that test data draws broken line graph to logging.
Fig. 2 indicates the detection yield value of additional interference signal at different center frequency.As can be seen that in low-frequency range being
Preferably, gain detection of the interference signal on deformation of transformer winding tester affects most 1kHz～100kHz frequency-selective filterings performance
It is little；It is 100kHz～600kHz in Mid Frequency, impact of the interference signal to deformation of transformer winding tester gain accuracy of detection
Start to highlight, testing result fluctuates in a smaller range；In high band it is>600kHz, interference signal is to gain detection essence
The impact of degree is maximum, the detection error for maximum 0.6dB occur, but still meets<The frequency-selective filtering index of 0.9691dB.Cause
This, can be determined that out from table 2 and Fig. 2, tests the two deformation of transformer winding tester frequency-selective filtering performances for adopting and meets
《DL/T911-2004》Requirement.
According to the frequency-selecting scope of mid frequency ± 2%, as frequency increases, the mid frequency frequency band increase of frequency-selective filtering：
When frequency sweep is 1kHz, a width of 0.98kHz～1.02kHz of frequency-selecting band, test result receive 0.4kHz, the interference signal shadow of narrower bandwidth
Ring；When swept-frequency signal is 1000kHz, frequency-selecting band a width of 980kHz～1020kHz, test result is by 40kHz, large bandwidth
Interference signal affects.Therefore, it is to improve deformation of transformer winding tester frequency-selective filtering performance, should be in high band during analog filtering
Wave filter of the design with preferable filtering performance, should improve high band sampling precision and increase sampling number during digital filtering.
Above-described specific embodiment, has been carried out further to the purpose of the present invention, technical scheme and beneficial effect
Describe in detail, the be should be understood that specific embodiment that the foregoing is only the present invention is not intended to limit the present invention
Protection domain, all any modification, equivalent substitution and improvements within the spirit and principles in the present invention, done etc. all should include
Within protection scope of the present invention.
Claims (7)
1. it is a kind of judge deformation of transformer winding tester frequency-selective filtering performance system, it is characterised in that include：
Signal generator, exports the sinusoidal interference signal of given frequency and amplitude；
Adder, the output signal and signal to the tester in single-frequency point detection pattern and Gaster Sus domestica fixed frequency sinusoidal signal
The output signal of generator is added；
Attenuator, decays to the output signal of adder, and deamplification is sent to the response signal detection of tester
Port.
2. a kind of system for judging deformation of transformer winding tester frequency-selective filtering performance according to claim 1, which is special
Levy and be：Also include the oscillograph for being detected to the signal amplitude and frequency of two inputs of signal generator.
3. a kind of system for judging deformation of transformer winding tester frequency-selective filtering performance according to claim 1, which is special
Levy and be：The amplitude operational linearity of the adder is less than 1%.
4. it is a kind of judge deformation of transformer winding tester frequency-selective filtering performance method, it is characterised in that comprise the following steps：
A, deformation of transformer winding tester output sinusoidal signal V1T (), its rate of scanning are f0, amplitude is A, and phase place is j0；Letter
Number source output sinusoidal signal V2T (), its frequency are kf0, amplitude is α A, and phase place is j1；
B, to V1(t) and V2T () carries out in-phase proportion addition and obtains V (t)；
C, attenuation operations are carried out to V (t) and the signal after being decayedV δ(t) and send the signal to deformation of transformer winding
The response signal detection port of tester；
D, deformation of transformer winding tester output signal are Vout(t), and calculate frequency sweep gain；
E, by frequency sweep gain and standard settingIt is compared to judge deformation of transformer winding tester frequency-selective filtering
Energy.
5. a kind of method for judging deformation of transformer winding tester frequency-selective filtering performance according to claim 4, which is special
Levy and be：It is described。
6. a kind of method for judging deformation of transformer winding tester frequency-selective filtering performance according to claim 5, which is special
Levy and be：It is described。
7. a kind of method for judging deformation of transformer winding tester frequency-selective filtering performance according to claim 4, which is special
Levy and be：In step E, when frequency sweep gain is less than or equal to standard settingWhen deformation of transformer winding tester frequency-selecting filter
Ripple performance meets the requirements.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109525212A (en) * | 2018-12-29 | 2019-03-26 | 西安交通大学 | A kind of intelligent scanning signal processing unit and working method |
| CN110021303A (en) * | 2019-03-27 | 2019-07-16 | 广州飞达音响股份有限公司 | A kind of Dante digital audio frequency processing method and system for rewriting noise and frequency sweep processing |
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| CN101545962A (en) * | 2009-04-21 | 2009-09-30 | 江苏省电力试验研究院有限公司 | Integral check system of FRA-type winding deformation tester |
| CN103712551A (en) * | 2013-12-04 | 2014-04-09 | 国家电网公司 | Power distribution network transformer low-voltage winding deformation on-line monitoring device and method |
| CN104535955A (en) * | 2015-01-15 | 2015-04-22 | 国网四川省电力公司电力科学研究院 | Calibration device and method of transformer frequency response method winding deformation tester |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2001084169A1 (en) * | 2000-05-04 | 2001-11-08 | Georgia Tech Research Corporation | System and method for on-line impulse frequency response analysis |
| CN101545962A (en) * | 2009-04-21 | 2009-09-30 | 江苏省电力试验研究院有限公司 | Integral check system of FRA-type winding deformation tester |
| CN103712551A (en) * | 2013-12-04 | 2014-04-09 | 国家电网公司 | Power distribution network transformer low-voltage winding deformation on-line monitoring device and method |
| CN104535955A (en) * | 2015-01-15 | 2015-04-22 | 国网四川省电力公司电力科学研究院 | Calibration device and method of transformer frequency response method winding deformation tester |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109525212A (en) * | 2018-12-29 | 2019-03-26 | 西安交通大学 | A kind of intelligent scanning signal processing unit and working method |
| CN110021303A (en) * | 2019-03-27 | 2019-07-16 | 广州飞达音响股份有限公司 | A kind of Dante digital audio frequency processing method and system for rewriting noise and frequency sweep processing |
| CN110021303B (en) * | 2019-03-27 | 2021-06-15 | 广州飞达音响股份有限公司 | Dante digital audio processing method and system for rewriting noise and frequency sweep processing |
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| CN106610464B (en) | 2019-06-18 |
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