CN105301460A - Test method for research of transmission characteristics of ultrahigh frequency signals by partial discharge of transformer - Google Patents

Test method for research of transmission characteristics of ultrahigh frequency signals by partial discharge of transformer Download PDF

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CN105301460A
CN105301460A CN201510840143.8A CN201510840143A CN105301460A CN 105301460 A CN105301460 A CN 105301460A CN 201510840143 A CN201510840143 A CN 201510840143A CN 105301460 A CN105301460 A CN 105301460A
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signal
transformer
frequency signal
discharge
sensor
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CN105301460B (en
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柯春俊
杜劲超
杨贤
陈冰心
马志钦
林春耀
周丹
谢波
崔鲁
李永森
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Chongqing University
Electric Power Research Institute of Guangdong Power Grid Co Ltd
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Chongqing University
Electric Power Research Institute of Guangdong Power Grid Co Ltd
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Abstract

Provided is a test method for the research of transmission characteristics of ultrahigh frequency signals by partial discharge of a transformer. The test method includes following steps: determining sensors and a discharge source according to the internal structure of a real-model transformer; high voltage is added between electrodes of the discharge source, and enabling the internal part of the transformer to generate partial discharge; installing the sensors at positions with different distances from the discharge source, and analyzing attenuation change conditions of frequency spectrum, phase, and time delay of the ultrahigh frequency signals by partial discharge; comparing the condition of the ultrahigh frequency signals by partial discharge through winding attenuation and the condition of direct reception of the signals by the sensors without passing through the winding, and analyzing changes of the signal spectrum, the phase, and the time delay; and comparing original signals and the ultrahigh frequency signals by partial discharge after the transmission of different paths in terms of frequency spectrum, phase, and time delay, and researching on the influences of different transmission paths on the transmission of the ultrahigh frequency signals. According to the method, the transmission rule and influence factors of the ultrahigh frequency signals in the transformer can be more truly researched, and important guidance significance is attached to on-line monitoring of the ultrahigh frequency signals by partial discharge of the transformer in practical operation.

Description

A kind of test method studying transformer partial discharge super high frequency signal propagation characteristics
Technical field
The invention belongs to electric equipment test technical field, relate to a kind of test method studying transformer partial discharge super high frequency signal, be particularly useful for the propagation characteristic research experiment to ultra-high frequency signal.
Technical background
Under the effect of electric field, the electrical discharge phenomenon that between conductor, SI semi-insulation region is breakdown is called shelf depreciation.Shelf depreciation is the principal element causing transformer insulated premature failure, is also the mark of Transformer Insulation Aging and deterioration, therefore has important academic significance and using value to the experimental study of partial discharge of transformer on-line monitoring.
Some electrical phenomenas and non-electrical phenomena can be produced in shelf depreciation process, as electromagnetic radiation, electric pulse, sound wave, heating, generation gas etc., the monitoring method of its correspondence has ultrahigh frequency monitoring method, pulse current method, monitoring ultrasonic method, temperature monitoring method, vapor-phase chromatography etc. respectively.The plurality of advantages such as wherein ultrahigh frequency monitoring method is highly sensitive because having, abundant information, and antijamming capability is strong, and location is convenient, are applied in Partial Discharge Online Monitoring of Transformers more and more widely.
But due to inside transformer complex structure, when the ultra-high frequency signal that shelf depreciation produces is propagated, be subject to the impact of iron core, insulating board, wire, transformation wall etc. wherein, occur repeatedly to roll over, reflect.In transformer partial discharge super high frequency detects, ultra-high frequency antenna receives the hyper band spatial electromagnetic ripple from point of discharge, the various factor affecting local discharge superhigh frequency signal folding, reflection and decay, add the complicacy of inside transformer local discharge superhigh frequency signal propagation path, not only may affect amplitude and the waveform of ultra-high frequency antenna measuring-signal, also make the location adopting local discharge superhigh frequency signal that error occurs, be unfavorable for extracting useful information from the testing result of ultra-high frequency signal, add the difficulty that local discharge superhigh frequency detects.Therefore be necessary to carry out the test of local discharge superhigh frequency signal propagation characteristics, further investigation ultra-high frequency signal, in the propagation law of inside transformer and influence factor, further develops ultra high frequency detection technology.
At present, the test method of research local discharge superhigh frequency signal propagation characteristics is the transformer model for simplifying mostly, such as, by oil-filled in metal cabinet and add cardboard or Transformer Winding, the impact that Research on Oil middle distance, cardboard or winding are propagated ultra-high frequency signal.Although the propagation characteristic of ultra-high frequency signal in inside transformer can be reflected to a certain extent by these tests, because experimental enviroment to differ comparatively large with true discharge environment, be difficult to the propagation characteristic of ultra-high frequency signal in transformer under reflection truth.Therefore, being necessary to build true type transformer test platform, by placing Partial Discharge Sources in inside transformer, uhf sensor being installed by casing, study the propagation characteristic of ultra-high frequency signal, can the propagation law of reflection ultra-high frequency signal in transformer of objective more.
Given this, the invention provides a kind of test method studying transformer partial discharge super high frequency signal propagation characteristics, based on true type transformer test platform, the propagation law of ultra-high frequency signal in transformer and influence factor can be studied more realistically, to the on-line monitoring of transformer partial discharge super high frequency signal in actual motion, there is great importance.
Summary of the invention
Technical matters to be solved by this invention is the deficiency existed for existing test method, a kind of test method of research transformer partial discharge super high frequency signal is newly proposed, this test method studies the propagation characteristic of ultra-high frequency signal based on true type transformer test platform, can the objective ground propagation law of reflection ultra-high frequency signal in transformer and influence factor more.
For achieving the above object, the technical solution used in the present invention is:
Study a test method for transformer partial discharge super high frequency signal propagation characteristics, it is characterized in that, described test method comprises the following steps:
Step one: according to true type inside transformer structure, determine the installation site of sensor and discharge source;
Step 2: discharge source is arranged on transformer-cabinet, high voltage between discharge source electrode, makes inside transformer produce shelf depreciation;
Step 3: at the position sensor installation that distance discharge source is different, local discharge superhigh frequency signal is gathered with oscillograph, analyze the attenuation change situation of the frequency spectrum of local discharge superhigh frequency signal, phase place, time delay, carry out the impact that Research on Oil middle distance is propagated shelf depreciation ultra-high frequency signal;
Step 4: situation about decaying through winding to shelf depreciation ultra-high frequency signal and signal are directly contrasted by the situation that sensor receives without winding, use oscillograph collection signal, analytic signal frequency spectrum, phase place, Delay Variation, the impact that research Transformer Winding is propagated ultra-high frequency signal;
Step 5: sensor is placed near discharge source, the local discharge superhigh frequency signal that this sensor is received is as original signal, and carry out the contrast of frequency spectrum, phase place, time delay from the local discharge superhigh frequency signal after different propagated, study the impact that different travel path is propagated ultra-high frequency signal.
The test method of research transformer partial discharge super high frequency signal propagation characteristics as above, also comprises following preferred version further:
In step one: according to inner structure and the external dimensions of transformer, with signal propagation path as much as possible for principle, determine the installation site of discharge source and sensor on transformer-cabinet.
In step 3: the local discharge superhigh frequency signal received with the sensor that oscillographic four road signal ports gather distance discharge source different distance simultaneously, signal data is imported in computer, observe local discharge superhigh frequency signal time delay situation of change and carry out FFT conversion, analytic signal frequency spectrum, phase place are with the Changing Pattern of distance.
In step 4: gather with oscillograph the local discharge superhigh frequency signal that two-way sensor uploads simultaneously, wherein a road is through the signal of winding decay, an other road is directly by signal that sensor receives without winding, guarantee two sensors to discharge source apart from identical simultaneously as far as possible, analyze the Changing Pattern of local discharge superhigh frequency signal.
In step 5: the multiple positions successively discharge source being placed on inside transformer, in the place sensors nearest apart from it, and the local discharge superhigh frequency signal that this sensor is received is as original signal, with the local discharge superhigh frequency signal of other three paths collections after different travel path in oscillograph four paths, the propagation law of analytic signal from the travel path of signal.
The invention has the advantages that: the invention provides a kind of test method studying transformer partial discharge super high frequency signal propagation characteristics.The method is compared with the test method of traditional simplified style transformer model test platform research ultra-high frequency signal propagation characteristic, and test findings more can reflect the propagation law of ultra-high frequency signal in transformer in objective ground, and the advantage of the method is specific as follows:
1. based on true type transformer test platform, more close with true discharge environment, more truly reflect the propagation characteristic of local discharge superhigh frequency signal.
2. due to the diversity of test method, the influence factor propagate multiple ultra-high frequency signal and various different travel path are studied, and reflect the propagation law of ultra-high frequency signal more comprehensively.
Accompanying drawing explanation
Fig. 1 is the test method process flow diagram that the present invention studies transformer partial discharge super high frequency signal propagation characteristics;
Fig. 2 is the schematic diagram implementing test method of the present invention at 110kV power transformer test platform.
Embodiment
In order to understand the present invention better, illustrate content of the present invention further below in conjunction with embodiment.
As shown in Figure 1, the invention provides a kind of test method studying transformer partial discharge super high frequency signal propagation characteristics, comprise following steps:
Step one: according to true type inside transformer structure, determine the installation site of sensor and discharge source;
According to inner structure and the external dimensions of transformer, with signal propagation path as much as possible for principle, determine the installation site of discharge source and sensor on transformer-cabinet.
Step 2: discharge source is arranged on transformer-cabinet, high voltage between discharge source electrode, makes inside transformer produce shelf depreciation;
Step 3: at the different position sensor installation of distance discharge source, use oscillograph collection signal, the attenuation change situation of the frequency spectrum of analytic signal, phase place, time delay, carrys out the impact that Research on Oil middle distance is propagated ultra-high frequency signal;
With the local discharge superhigh frequency signal that the sensor that oscillographic four road signal ports gather distance discharge source different distance receives simultaneously, by in data importing computer, observation signal Delay Variation situation also carries out FFT conversion, and analytic signal frequency spectrum, phase place are with the Changing Pattern of distance.
Step 4: situation about decaying through winding to signal and signal are directly contrasted by the situation that sensor receives without winding, use oscillograph collection signal, analytic signal frequency spectrum, phase place, Delay Variation, the impact that research Transformer Winding is propagated ultra-high frequency signal;
Gather two-way sensor signal with oscillograph simultaneously, wherein a road is through the signal of winding decay, an other road is without winding directly by the signal that sensor receives, and guarantees two sensors to discharge source apart from identical, the Changing Pattern of analytic signal simultaneously as far as possible.
Step 5: sensor is placed near power supply placement, the signal that this sensor is received is as original signal, and carry out the contrast of frequency spectrum, phase place, time delay from the signal after different propagated, study the impact that different travel path is propagated ultra-high frequency signal;
Successively discharge source is placed on multiple positions of inside transformer, in the place sensors nearest apart from it, and the signal that this sensor is received is as original signal, with the local discharge superhigh frequency signal of other three paths collections after different travel path in oscillograph four paths, the propagation law of analytic signal from the travel path of signal.
As shown in Figure 2, the present embodiment is for 110kV power transformer test platform.
Embodiment is as follows:
1. according to inner structure and the external dimensions of transformer, with signal propagation path as much as possible for principle is at the 1-8 place perforate of transformer tank body position, mounting flange, discharge source model and sensor are installed Unified Model design, thus discharge source not only can be placed but also can place sensor by 1-8 place, position.
2. place discharge source at position 2 place, when producing shelf depreciation, with the signal that collection position 3,4 place's sensor while of oscillograph receives, then discharge source is placed on position 8 place, with the signal that collection position 6,7 place's sensor while of oscillograph receives, by in data importing computer, observation signal Delay Variation situation also carries out FFT conversion, and analytic signal frequency spectrum, phase place are with the Changing Pattern of distance.
3. place discharge source at position 2 place, when producing shelf depreciation, with the signal that collection position 4,8 place's sensor while of oscillograph receives, position 2 is substantially identical with the distance of position 8 to position 4, can be used for analyzing winding to the impact of ultra-high frequency signal propagation characteristic.
4. place discharge source at position 2 place, because position 3 distance and position 2 is nearer, the signal that therefore sensor at position 3 place can be received is as original signal, then be captured in oscillograph the signal that position 1,5,6,7,8 place's sensor receives respectively, study the impact that other multiple travel paths are propagated ultra-high frequency signal.
5. in like manner, sensor can be placed on respectively 3-8 place, position, the signal that sensor apart from its proximal most position is received is as original signal, the signal that other position sensors receive is gathered respectively with oscillograph, and data are processed, analyze the impact of different travel path on ultra-high frequency signal, therefrom find out rule and influence factor that ultra-high frequency signal propagates in transformer.
These are only embodiments of the invention, be not limited to the present invention, therefore, within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within right of the present invention.

Claims (5)

1. study a test method for transformer partial discharge super high frequency signal propagation characteristics, it is characterized in that, described test method comprises the following steps:
Step one: according to true type inside transformer structure, determine the installation site of sensor and discharge source;
Step 2: discharge source is arranged on transformer-cabinet, high voltage between discharge source electrode, makes inside transformer produce shelf depreciation;
Step 3: at the position sensor installation that distance discharge source is different, local discharge superhigh frequency signal is gathered with oscillograph, analyze the attenuation change situation of the frequency spectrum of local discharge superhigh frequency signal, phase place, time delay, carry out the impact that Research on Oil middle distance is propagated shelf depreciation ultra-high frequency signal;
Step 4: situation about decaying through winding to shelf depreciation ultra-high frequency signal and signal are directly contrasted by the situation that sensor receives without winding, use oscillograph collection signal, analytic signal frequency spectrum, phase place, Delay Variation, the impact that research Transformer Winding is propagated ultra-high frequency signal;
Step 5: sensor is placed near discharge source, the local discharge superhigh frequency signal that this sensor is received is as original signal, and carry out the contrast of frequency spectrum, phase place, time delay from the local discharge superhigh frequency signal after different propagated, study the impact that different travel path is propagated ultra-high frequency signal.
2. test method according to claim 1, is characterized in that:
In step one: according to inner structure and the external dimensions of transformer, with signal propagation path as much as possible for principle, determine the installation site of discharge source and sensor on transformer-cabinet.
3. test method according to claim 1 and 2, is characterized in that:
In step 3: the local discharge superhigh frequency signal received with the sensor that oscillographic four road signal ports gather distance discharge source different distance simultaneously, signal data is imported in computer, observe local discharge superhigh frequency signal time delay situation of change and carry out FFT conversion, analytic signal frequency spectrum, phase place are with the Changing Pattern of distance.
4. test method according to claim 1 and 2, is characterized in that:
In step 4: gather with oscillograph the local discharge superhigh frequency signal that two-way sensor uploads simultaneously, wherein a road is through the signal of winding decay, an other road is directly by signal that sensor receives without winding, guarantee two sensors to discharge source apart from identical simultaneously as far as possible, analyze the Changing Pattern of local discharge superhigh frequency signal.
5. test method according to claim 1 and 2, is characterized in that:
In step 5: the multiple positions successively discharge source being placed on inside transformer, in the place sensors nearest apart from it, and the local discharge superhigh frequency signal that this sensor is received is as original signal, with the local discharge superhigh frequency signal of other three paths collections after different travel path in oscillograph four paths, the propagation law of analytic signal from the travel path of signal.
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CN106093737A (en) * 2016-08-18 2016-11-09 广东电网有限责任公司电力科学研究院 A kind of transformer partial discharge signal propagation characteristics test method and method for diagnosing faults
CN106405341A (en) * 2016-07-15 2017-02-15 国网甘肃省电力公司电力科学研究院 Method used for reducing partial discharge ultrahigh frequency signal
CN110082658A (en) * 2019-05-30 2019-08-02 国网上海市电力公司 Superfrequency-optical signal uniformity test unit and method in GIS
CN113702779A (en) * 2021-08-23 2021-11-26 国网山东省电力公司电力科学研究院 Local discharge ultrahigh frequency sensor field calibration method for transformer
CN114563663A (en) * 2022-01-18 2022-05-31 山东大学 Experimental device and method for discharging in transformer oil under alternating voltage
CN114839495A (en) * 2022-06-30 2022-08-02 江苏苏能森源电气有限公司 Transformer partial discharge abnormity detection method based on artificial intelligence
CN114966382A (en) * 2022-04-25 2022-08-30 国网山西省电力公司电力科学研究院 Mechanical and electrical combined test system for gas insulated combined electrical apparatus
CN117310247A (en) * 2023-11-30 2023-12-29 深圳市鼎阳科技股份有限公司 Oscilloscope and power supply probe frequency response compensation method thereof

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106405341A (en) * 2016-07-15 2017-02-15 国网甘肃省电力公司电力科学研究院 Method used for reducing partial discharge ultrahigh frequency signal
CN106093737A (en) * 2016-08-18 2016-11-09 广东电网有限责任公司电力科学研究院 A kind of transformer partial discharge signal propagation characteristics test method and method for diagnosing faults
CN106093737B (en) * 2016-08-18 2019-02-12 广东电网有限责任公司电力科学研究院 A kind of transformer partial discharge signal propagation characteristics test method and method for diagnosing faults
CN110082658A (en) * 2019-05-30 2019-08-02 国网上海市电力公司 Superfrequency-optical signal uniformity test unit and method in GIS
CN113702779A (en) * 2021-08-23 2021-11-26 国网山东省电力公司电力科学研究院 Local discharge ultrahigh frequency sensor field calibration method for transformer
CN114563663A (en) * 2022-01-18 2022-05-31 山东大学 Experimental device and method for discharging in transformer oil under alternating voltage
CN114966382A (en) * 2022-04-25 2022-08-30 国网山西省电力公司电力科学研究院 Mechanical and electrical combined test system for gas insulated combined electrical apparatus
CN114839495A (en) * 2022-06-30 2022-08-02 江苏苏能森源电气有限公司 Transformer partial discharge abnormity detection method based on artificial intelligence
CN114839495B (en) * 2022-06-30 2022-09-20 江苏苏能森源电气有限公司 Transformer partial discharge abnormity detection method based on artificial intelligence
CN117310247A (en) * 2023-11-30 2023-12-29 深圳市鼎阳科技股份有限公司 Oscilloscope and power supply probe frequency response compensation method thereof
CN117310247B (en) * 2023-11-30 2024-03-01 深圳市鼎阳科技股份有限公司 Oscilloscope and power supply probe frequency response compensation method thereof

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