CN106610464B - Determine the system and method for deformation of transformer winding tester frequency-selective filtering performance - Google Patents
Determine the system and method for deformation of transformer winding tester frequency-selective filtering performance Download PDFInfo
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- CN106610464B CN106610464B CN201611040220.2A CN201611040220A CN106610464B CN 106610464 B CN106610464 B CN 106610464B CN 201611040220 A CN201611040220 A CN 201611040220A CN 106610464 B CN106610464 B CN 106610464B
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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
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Abstract
The invention discloses a kind of system and methods for determining deformation of transformer winding tester frequency-selective filtering performance, comprising: signal generator exports the sinusoidal interference signal of given frequency and amplitude；Adder is added the output signal of tester in single-frequency point detection pattern and known fixed frequency sine signal with the output signal of signal generator；Attenuator decays to the output signal of adder, and the response signal that deamplification is sent to tester is detected port；Frequency-selective filtering band attenuation is required to be converted into gain requirement, comprehensive judgement is carried out to frequency-selective filtering characteristic using the testing result of tester, solves the problems, such as that tester is disassembled or destroyed to existing needs when to tester frequency-selective filtering performance detection using the error amount secondary indication tester frequency-selective filtering characteristic superiority and inferiority degree of gain detection.
Description
Technical field
The present invention relates to transformer fault detection fields, and in particular to a kind of judgement deformation of transformer winding tester frequency-selecting
The method of filtering performance.
Background technique
Transformer is the core equipment of power grid, and winding deformation is one of most common internal fault of power transformer, in electricity
Under the action of power and mechanical force, irreversible variation occurs for the size or shape of winding, after winding is locally deformed with, even if
It does not damage immediately, it is also possible to leave serious potential faults." prevent 25 emphasis of power generation major accident from wanting
Ask " and " 18 great anti-accident measures of power grid of State Grid Corporation of China " deformation test of transformer winding is placed on it is highly important
Position is, it is specified that method of frequency response method test winding deformation is the pilot project that 110 (66) kV and the above transformer must carry out.It actively develops
Deformation of transformer winding diagnostic work, discovery in time has the transformer of winding deformation potential faults, and in a planned way carries out hanging cover
It checks and maintenance, a large amount of human and material resources can be not only saved, to preventing the generation of Accident of Transformer from also having and its important work
With.
To test deformation of transformer winding, each power generation unit is generallyd use based on frequency response analysis
The deformation of transformer winding tester (hereinafter referred to as tester) of (Frequency Response Analysis, FRI).Frequency
Response analysis method is the method for common test winding deformation both at home and abroad, and the equivalent circuit of transformer is considered as the two of total ground
Port network, after winding deformation, inner parameter variation will lead to transmission function and change, by analyzing and comparing transformer
Frequency response characteristic, it can be found that whether transformer winding deforms [9-10].
Tester is as shown in Figure 1, wherein Vs is sinusoidal signal output port, V is pumping signal detection port, V2 is loud
Induction signal detects port；Have a sine wave exciting signal output interface and two independent signal detection interfaces, as one
Kind test equipment, general technology part should meet the requirement of " GB/T 6587-2012 electronic measuring instrument general specification ".For
Meet on-the-spot test, reduces influence of other frequency signals to test result, anti-interference ability, i.e. frequency-selective filtering performance, i.e.,
The ability for filtering the interference signal in addition to swept-frequency signal, as the basic function requirement 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 method carries out the assessment and judgement of science to the performance indicator.
It for discriminating test instrument frequency-selective filtering performance, is generally tested using spectrum analyzer, however, tester frequency sweep is believed
Number output and response signal detection are integrated in instrument internal, the performance of filter test of response signal test side need to disassemble or
Destroy tester.Therefore it needs to study a kind of more effective, direct determination method, to frequency-selective filtering when calibrating convenient for tester
Characteristic is determined.
Summary of the invention
In order to solve the above-mentioned technical problem the present invention provides a kind of judgement deformation of transformer winding tester frequency-selective filtering
The system and method for energy.
The present invention is achieved through the following technical solutions:
A method of determining deformation of transformer winding tester frequency-selective filtering performance, comprising:
Signal generator exports the sinusoidal interference signal of given frequency and amplitude；
Adder, in single-frequency point detection pattern and the output signal of the tester of pork tripe 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
Detect port；
The following steps are included:
A, deformation of transformer winding tester exports sinusoidal signal V1(t), scan frequency f0, amplitude A, phase isSignal source exports sinusoidal signal V2(t), frequency kf0, amplitude is α A, and phase is
B, to V1(t) and V2(t) in-phase proportion is carried out to be added to obtain V (t)；
C, the signal V after V (t) being carried out attenuation operations and decayedδ(t) and transformer winding is sent the signal to
The response signal of deformation tester detects port；
D, deformation of transformer winding tester output signal is Vout(t), and frequency sweep gain is calculated；
E, frequency sweep gain is compared with standard specified value Δ δ to judge deformation of transformer winding tester frequency-selective filtering
Performance.
The amplitude that influence of the interference signal of this programme to tester mainly exports pumping signal interferes, and makes to ring
The sinusoidal signal virtual value of induction signal detection port changes, and influences the accuracy of gain detection.Its basic ideas is that will mark
The band attenuation that standard proposes requires to be converted into gain requirement, is integrated using the testing result of tester to frequency-selective filtering characteristic
Determine, the error amount secondary indication tester frequency-selective filtering characteristic superiority and inferiority degree detected using gain.It can avoid using the present apparatus
Dismantling or destruction to tester, meet on-the-spot test and calibration, meet the working principle of instrument.
Preferably, further include for two input terminals of signal generator signal amplitude and showing of being detected of frequency
Wave device.Oscillograph can show the amplitude and frequency size of tester output drive signal, and be adjusted based on this amplitude and frequency
The signal amplitude and frequency of function signal generator output, guarantee that signal during frequency-selective filtering performance judgment will not occur
Variation.
Preferably, the amplitude operational linearity of the adder is less than 1%.Adder is used to function signal generator
The pumping signal linear, additive of output signal and tester, the amplitude for the accuracy for guaranteeing this test macro, adder are linear
Degree must be higher, and operational linearity is less than 1%, i.e. theoretical maximum deviation delta max < Voutmax*1/100 of measurement point, for example,
When maximum output voltage is 20V, measurement point maximum deviation < 0.2V guarantees that test macro determines the accuracy of result.
The result of frequency-selective filtering performance judgment indicated using detection gain error absolute value, detection error absolute value and letter
The attenuation coefficient that number source output signal amplitude and deformation of transformer winding tester require is related, when function signal generator exports
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 as 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 δ≤0.9691.
Preferably, in step E, when frequency sweep gain is less than or equal to standard specified value Δ δ, deformation of transformer winding is tested
Instrument frequency-selective filtering performance meets the requirements.
Preferably, the V1(t) scan frequency is f0Less than or equal to 600kHz.
Compared with prior art, the present invention at least having the following advantages and benefits:
This method requires band attenuation to be converted into gain requirement, using the absolute error value of gain come indirect judgement test
The frequency-selective filtering performance of instrument carries out comprehensive judgement to frequency-selective filtering characteristic using the testing result of tester, without dismantling test
Frequency-selecting filter inside instrument, meets on-the-spot test and calibration, meets the working principle of instrument.
Detailed description of the invention
Attached drawing described herein is used to provide to further understand the embodiment of the present invention, constitutes one 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 system of the invention.
Fig. 2 is that this test data draws line chart.
Specific embodiment
To make the objectives, technical solutions, and advantages of the present invention clearer, below with reference to embodiment and attached drawing, to this
Invention is described in further detail, and exemplary embodiment of the invention and its explanation for explaining only the invention, are not made
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 according to " DL/
The frequency response analysis method of T911-2004 winding deformation of power transformer " and its requirement of 2016 revised editions to performance indicator,
The determination method for frequency-selective filtering experimental performance index is proposed, and the deformation of transformer winding tester of mainstream producer is selected
Frequency filtering performance is tested.Test is determined by carrying out Sichuan Electric Power production unit deformation of transformer winding test equipment scene
It works with performance evaluation, it was confirmed that the method for proposition is reliable, meets the actual working condition of tester.Finally to raising tester
Frequency-selective filtering performance propose suggestion.
Embodiment
A kind of system determining deformation of transformer winding tester frequency-selective filtering performance as shown in Figure 1, including signal occur
The attenuator of device, adder and standard；The sinusoidal interference signal of signal generator output given frequency and amplitude；Adder is to place
In the output signal of the tester of single-frequency point detection pattern and pork tripe fixed frequency sinusoidal signal and the output letter of signal generator
It number is added；Attenuator decays to the output signal of adder, and the response that deamplification is sent to tester is believed
Number detection port.
It further include for the signal amplitude and the oscillograph that is detected of frequency to two input terminals of signal generator.
The amplitude operational linearity of the adder is less than 1%.
For above-mentioned apparatus, the method for frequency-selective filtering performance is determined are as follows: a kind of judgement deformation of transformer winding tester
The method of frequency-selective filtering performance, which comprises the following steps:
A, deformation of transformer winding tester exports sinusoidal signal V1(t), scan frequency f0, amplitude A, phase isSignal source exports sinusoidal signal V2(t), frequency kf0, amplitude is α A, and phase is
B, to V1(t) and V2(t) in-phase proportion is carried out to be added to obtain V (t)；
C, the signal V after V (t) being carried out attenuation operations and decayedδ(t) and transformer winding is sent the signal to
The response signal of deformation tester detects port；
D, deformation of transformer winding tester output signal is Vout(t), and frequency sweep gain is calculated；
E, frequency sweep gain is compared with standard specified value Δ δ 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 V1(t) frequency is f0, amplitude A, phase isLetter
Number source exports sinusoidal signal V2(t) it is used as interference signal, frequency is k times of signal V1(t) frequency, i.e. kf0, amplitude is α times of signal
V1(t) amplitude, i.e. α A, phase are set asThen there is formula (1):
Adder is to V1(t) and V2(t) it carries out in-phase proportion to be added to obtain V (t), if proportionality coefficient is 1, by adder
Signal V (t) afterwards are as follows:
V (t)=V1(t)+V2(t)；
Signal V after V (t) is carried out attenuation operations and decayedδ(t) and transformer winding change is sent the signal to
The response signal of shape tester detects port, if the attenuation of attenuator is δ dB, i.e. the 10 of signal amplitude decaying input signalδ/20Times, then pass through the signal V after standard attenuatorδ(t) are as follows:
To input signal in frequency f inside deformation of transformer winding tester0Place has the function of frequency-selective filtering, can be to except f0
Signal amplitude is decayed in addition.The input signal that deformation of transformer winding tester response signal detects 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 passes through transformation
Signal V after device winding deformation tester frequency-selective filteringout(t) are as follows:
Wherein,It is filter to the phase shifting angle of interference signal, tester calculates frequency sweep gain A m:
Wherein VoutAnd VinFor the root-mean-square value of sinusoidal signal:
Frequency sweep gain A m is compared with standard specified value Δ δ to judge deformation of transformer winding tester frequency-selective filtering
Performance.
Using detection gain absolute error value determine, therefore, Judging index and test when standard attenuator occurrence without
It closes, in test without selecting specific attenuator, but Ying Zhiqi attenuation.
Requirement according to standard to frequency-selective filtering performance, -6dB bandwidth should be less than the 2% of scan frequency, i.e., transformer around
The frequency-selective filtering function of group deformation tester should at least decay to the signal being located at output sinusoidal frequency value ± 2% detected
For the half of the signal open width value.So standard specified value is theoretical are as follows:
I.e.
When indicating frequency-selective filtering performance with absolute error, due to external standard attenuator attenuation δ it is known that so:
From above formula it is found that the factor for influencing frequency-selective filtering performance indicator is amplitude times of the external interference signals to pumping signal
α and filter itself are counted to the attenuation multiple β of interference signal.According to requiring, deformation of transformer winding tester is to detecting
The half of the signal open width value should at least be decayed to by exporting the signal at sinusoidal frequency value positioned at (1 ± 2%) times, i.e. and β≤
0.5, the amplitude that when verification sets input nonlinearities signal is identical as test signal, i.e. α=1, it can be deduced that the index of judgement are as follows:
Therefore, the index that frequency-selective filtering is calibrated in this case are as follows:
|Δδ|≤0.9691dB。
Following table gives under the conditions of α=1, the calibration theory calls under different frequency-selective filtering decay indices.
In order to which the correctness to above-mentioned determination method is verified, two that current domestic each electric power enterprise is generally equipped with are selected
Kind deformation of transformer winding tester is verified, and is tested according to the following steps:
1) deformation of transformer winding tester is set as single-frequency point Scanning Detction mode, and scan frequency Fo is respectively set to
1kHz,10kHz,100kHz,500kHz,1000kHz；
2) digital oscilloscope measures the signal amplitude and frequency of two input terminals of adder calculator simultaneously；
3) signal generator exports sinusoidal signal, and frequency is respectively set to 0.98Fo and 1.02Fo, setting output amplitude with
It is identical that deformation of transformer winding tester exports sine wave signal amplitude；
4) adder is built by broadband operational amplifier, and amplitude operational linearity is preferably better than 1%, for transformer
Winding deformation tester carries out in-phase proportion with the sine wave signal that signal generator exports and is added, and proportionality coefficient is taken as 1；
5) attenuation of selection criteria 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 signal.
Logging is as shown in table 2, and it is as shown in Figure 2 that test data draws line chart.
Fig. 2 shows the detection yield value of additional interference signal at different center frequency.As can be seen that being in low-frequency range
1kHz~100kHz frequency-selective filtering performance is best, and interference signal influences most the gain of deformation of transformer winding tester detection
It is small；In Mid Frequency, that is, 100kHz~600kHz, influence of the interference signal to deformation of transformer winding tester gain detection accuracy
Start to highlight, testing result fluctuates in a smaller range；It is > 600kHz in high band, interference signal detects essence to gain
The influence of degree is maximum, the detection error of maximum 0.6dB occurs, but still meets the < frequency-selective filtering index of 0.9691dB.Cause
This, can be determined that out from table 2 and Fig. 2, and two deformation of transformer winding tester frequency-selective filtering performances for testing use meet
The requirement of " DL/T 911-2004 ".
According to the frequency-selecting range of centre frequency ± 2%, as frequency increases, the centre frequency frequency band of frequency-selective filtering increases:
When frequency sweep is 1kHz, frequency-selecting bandwidth is 0.98kHz~1.02kHz, and test result is by 0.4kHz, the interference signal shadow of narrower bandwidth
It rings；When swept-frequency signal is 1000kHz, frequency-selecting bandwidth is 980kHz~1020kHz, and test result is by 40kHz, large bandwidth
Interference signal influences.It therefore, is to improve deformation of transformer winding tester frequency-selective filtering performance, when analog filtering should be in high band
The filter with preferable filtering performance is designed, when digital filtering should improve high band sampling precision and increase sampling number.
Above-described specific embodiment has carried out further the purpose of the present invention, technical scheme and beneficial effects
It is described in detail, it should be understood that being not intended to limit the present invention the foregoing is merely a specific embodiment of the invention
Protection scope, all within the spirits and principles of the present invention, any modification, equivalent substitution, improvement and etc. done should all include
Within protection scope of the present invention.
Claims (6)
1. a kind of method for determining deformation of transformer winding tester frequency-selective filtering performance, which is characterized in that this method used
System includes:
Signal generator exports the sinusoidal interference signal of given frequency and amplitude；
Adder, to the output signal and signal of the tester in single-frequency point detection pattern and output fixed frequency sinusoidal signal
The output signal of generator is added；
Attenuator decays to the output signal of adder, and the response signal that deamplification is sent to tester is detected
Port；
Method includes the following steps:
A, deformation of transformer winding tester exports sinusoidal signal V1(t), scan frequency f0, amplitude A, phase isLetter
Number source exports sinusoidal signal V2(t), frequency kf0, amplitude is α A, and phase is
B, to V1(t) and V2(t) in-phase proportion is carried out to be added to obtain V (t)；
C, the signal V after V (t) being carried out attenuation operations and decayedδ(t) and deformation of transformer winding is sent the signal to
The response signal of tester detects port；
D, output signal is V after deformation of transformer winding tester frequency-selective filteringout(t), and frequency sweep gain is calculated；
E, frequency sweep gain is compared with standard specified value Δ δ to judge deformation of transformer winding tester frequency-selective filtering
Energy.
2. a kind of system for determining deformation of transformer winding tester frequency-selective filtering performance according to claim 1, special
Sign is: the system further include for two input terminals of signal generator signal amplitude and the oscillography that is detected of frequency
Device.
3. a kind of system for determining deformation of transformer winding tester frequency-selective filtering performance according to claim 1, special
Sign is: the amplitude operational linearity of the adder is less than 1%.
4. a kind of method for determining deformation of transformer winding tester frequency-selective filtering performance according to claim 1, special
Sign is: described
5. a kind of method for determining deformation of transformer winding tester frequency-selective filtering performance according to claim 4, special
Sign is: Δ δ≤0.9691.
6. a kind of method for determining deformation of transformer winding tester frequency-selective filtering performance according to claim 1, special
Sign is: in step E, when frequency sweep gain is less than or equal to standard specified value Δ δ, deformation of transformer winding tester frequency-selecting is filtered
Wave performance meets the requirements.
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| 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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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
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2016
- 2016-11-11 CN CN201611040220.2A patent/CN106610464B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
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