CN103901282A - Method for testing high-voltage transmission line television interferences - Google Patents
Method for testing high-voltage transmission line television interferences Download PDFInfo
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- CN103901282A CN103901282A CN201410112817.8A CN201410112817A CN103901282A CN 103901282 A CN103901282 A CN 103901282A CN 201410112817 A CN201410112817 A CN 201410112817A CN 103901282 A CN103901282 A CN 103901282A
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Abstract
The invention provides a method for testing high-voltage transmission line television interferences. The method comprises the following steps of analyzing television signal frequency bands of a tested area and recording television images before television interferences, selecting a measuring position, selecting antennas according to the frequency range of television interferences, and selecting television interference field intensity frequencies and measuring television interference field intensity. According to the method for testing high-voltage transmission line television interferences, the television interference field intensity generated by corona of a high-voltage transmission line is measured, interfered television images are obtained at the same time, the interference degree of television signals and images is evaluated, and the blank of the current high-voltage transmission line television interference testing method is filled.
Description
Technical field
The present invention relates to a kind of method of testing, specifically relate to a kind of method of testing of ultra-high-tension power transmission line television interference (TVI).
Background technology
The current still method of ununified test project of transmitting and converting electricity television interference (TVI) in the world, different research organizations has designed different testing schemes.The method of testing that exemplifies two quasi-representatives is as follows.One class is the TVI test that the high frequency interference while discharging for laboratory inner insulator test product is carried out.The people such as Yoshitsugu SAWADA utilize laboratory, with seven wooden television antennas (Yagi type antenna) to quasi-insulator test product, measure the TVI of 90-222MHz, mainly at 94MHz frequency, use coaxial cable for high frequency (75 Europe), TVI meter, the situation that observation actual TV signal is disturbed.Another kind of method is to utilize spontaneous TV signal to test.Juette.G.W. utilize small-sized corona cage to carry out television interference (TVI) phenomenal research, adopting TV generator to produce standard television image signal mixes with the TVI signal that corona cage inner high voltage transmission line of electricity produces, at televisor observation picture effect, on TVI meter, record interference voltage.
Along with the develop rapidly of China's power grid construction, resident's living standard improves has higher requirement to cultural life, the TVI producing for high-tension line, when environmental impact investigation along the line, there is reflection, in view of recent domestic is to TVI research stagnation, the development of China's broadcast television technique, is necessary to propose a set of for the radio interference field intensity measuring method in ultra-high-tension power transmission line corona generation TV band.
Because electric pressure is high, UHV (ultra-high voltage) and UHV transmission line unavoidably produce corona phenomenon, thereby cause the electromagnetic environment problem of ultra-high-tension power transmission line.And show that for the measured result of current UHV (ultra-high voltage) and ultrahigh voltage alternating current transmission lines its main electromagnetic environment index all meets environmental requirement, but the resident of contiguous transmission line of electricity (or shaft tower) also responds, television image has been subject to interference, and has occurred a small amount of complaint.
The active interference of high frequency producing from ultra-high-tension power transmission line corona, at fine weather, electromagnetic interference (EMI) more than 30MHz, mainly from gap discharge, in the time that interference field strength is superimposed upon in vision carrier frequency, may exert an influence to the picture quality in TV band; Passive interference mainly from high-voltage alternating overhead transmission line and steel tower as metal parasitic element, or radio incoming wave signal is carried out shielding or blocked, radio incoming wave is produced to secondary radiation signal or shielded signal, the main electromagnetic field one of it and the radio incoming wave former TV signal that works, mass formation impact to received signal.The television interference (TVI) (TVI) that transmission line of electricity produces is referred to as in active interference and passive interference.
The at present method of testing high voltage transmission line of electricity TVI about how, the method of research institution of various countries is limited to self-condition, different method of testings has been proposed, frequency, test that wherein test is investigated do not propose unified standard with the key parameter such as antenna system, test position, thereby the measurement result constraint condition obtaining is many, is difficult to unify comparative analysis.Domestic correlative study does not almost have.
Summary of the invention
In order to overcome above-mentioned the deficiencies in the prior art, the invention provides a kind of method of testing of ultra-high-tension power transmission line television interference (TVI), the television interference (TVI) field intensity that ultra-high-tension power transmission line corona is produced is measured, and obtain the method for disturbed television image image simultaneously, the degree that TV signal and image are disturbed is assessed, and has filled up the blank of the television interference (TVI) method of testing of current testing high voltage transmission line of electricity.
In order to realize foregoing invention object, the present invention takes following technical scheme:
The method of testing that the invention provides a kind of ultra-high-tension power transmission line television interference (TVI), said method comprising the steps of:
Step 1: analyze the TV signal frequency range in tested area, and record the television image not being subject to before television interference (TVI);
Step 2: State selective measurements position;
Step 3: select antenna according to the frequency range of television interference (TVI);
Step 4: select television interference (TVI) field intensity frequency, and measure the field intensity of television interference (TVI).
In described step 1, analyze the TV signal frequency range in tested area by TV field strength meter, and record the television image not being subject to before television interference (TVI).
Be not subject to the television image method for recording before television interference (TVI) as follows:
In the time that ultra-high-tension power transmission line is out of service or away from least distance of 500m of tested ultra-high-tension power transmission line, by antenna collection signal, signal is averagely allocated to TV field strength meter and televisor through divider, described TV field strength meter one road signal connects computer hard disc and records image, another road signal input televisor, produce television image with recording image quality with video camera, and record television vision carrier frequency frequency a0.
In described step 2, select to be positioned near the straight line shelves sag minimum point that ultra-high-tension power transmission line is lower and near strained angled tower as measuring position.
To ultra-high-tension power transmission line produce television interference (TVI) carry out distributed measurement, at least measure to limit mutually outside 100m, if there is resident in 100m, should near resident's television receiving antenna position, carry out distributed measurement.
Distributed measurement method is: antenna is placed in to straight line shelves sag minimum point that ultra-high-tension power transmission line is lower over the ground on the vertical line of projection place and ultra-high-tension power transmission line, starts to measure the field intensity of television interference (TVI) for starting point in projection 20m place over the ground apart from limit ultra-high-tension power transmission line;
For strained angled tower, taking strained angled tower wire jumper over the ground subpoint as starting point, start to measure the field intensity of television interference (TVI).
In described step 3, according to the television image carrier frequency frequency a0 of record, estimate the frequency range of television interference (TVI), if television interference (TVI) frequency, within the scope of 20～200MHz, adopts biconical antenna, if within the scope of 200MHz～2GHz, adopt log-periodic antenna.
Described step 4 comprises the following steps:
Step 4-1: select television interference (TVI) field intensity frequency and carry out interference field strength test;
By the television image of recording, read the television carrier frequency being disturbed in conjunction with TV field strength meter, choose 75MHz as one of television interference (TVI) field intensity frequency, and using this frequency as carrying out field strength measurement with reference to evaluating frequency;
Step 4-2: the field intensity of measuring television interference (TVI);
A0 is television image carrier frequency frequency, selects frequency a1=a0-1, the frequency of a2=a0+1, carry out the measurement of television interference (TVI) field intensity, the field intensity that frequency a1 and a2 are corresponding is respectively N1 and N2, and because undesired signal frequency spectrum is continuous, the interference field strength N that obtains the generation of vision carrier frequency frequency a0 place is (N1+N2)/2.
Compared with prior art, beneficial effect of the present invention is:
1. solved the measurement problem that produces undesired signal when overlapping in television carrier frequency place's undesired signal and TV signal itself;
2. proposed in the simultaneously method of record tv picture of measurements interference signal strength, be conducive to undesired signal and picture and be disturbed situation and synchronize and contrast;
3. for ultra-high-tension power transmission line feature, principle and method that point position selection, frequency are selected have been proposed, significant to the assessment of disturbing.
4. the present invention proposes and a set ofly produce the radio interference field intensity measuring method in TV band for ultra-high-tension power transmission line corona, filled up the blank of the television interference (TVI) method of testing of current testing high voltage transmission line of electricity.
Brief description of the drawings
Fig. 1 is that undisturbed front television image is recorded schematic diagram;
Fig. 2 is standard television carrier frequency spectrogram;
Fig. 3 is the instrumentation plan of frequency a1 and a2 place television interference (TVI) field intensity;
Fig. 4 is the method for testing process flow diagram of ultra-high-tension power transmission line television interference (TVI).
Embodiment
Below in conjunction with accompanying drawing, the present invention is described in further detail.
The method of testing that the invention provides a kind of ultra-high-tension power transmission line television interference (TVI), said method comprising the steps of:
Step 1: analyze the TV signal frequency range in tested area, and record the television image not being subject to before television interference (TVI);
Step 2: State selective measurements position;
Step 3: select antenna according to the frequency range of television interference (TVI);
Step 4: select television interference (TVI) field intensity frequency, and measure the field intensity of television interference (TVI).
In described step 1, as Fig. 1, analyze the TV signal frequency range in tested area by TV field strength meter, and record the television image not being subject to before television interference (TVI).
Be not subject to the television image method for recording before television interference (TVI) as follows:
In the time that ultra-high-tension power transmission line is out of service or away from least distance of 500m of tested ultra-high-tension power transmission line, by antenna collection signal, signal is averagely allocated to TV field strength meter (band frequency spectrum function) and televisor (TV) through divider, described TV field strength meter one road signal connects computer hard disc and records image, another road signal input televisor, produce television image with recording image quality with video camera, and record television vision carrier frequency frequency a0(MHz).
In described step 2, select to be positioned near the straight line shelves sag minimum point that ultra-high-tension power transmission line is lower and near strained angled tower as measuring position.
To ultra-high-tension power transmission line produce television interference (TVI) carry out distributed measurement, at least measure to limit mutually outside 100m, if there is resident in 100m, should near resident's television receiving antenna position, carry out distributed measurement.
Distributed measurement method is: antenna is placed in to straight line shelves sag minimum point that ultra-high-tension power transmission line is lower over the ground on the vertical line of projection place and ultra-high-tension power transmission line, starts to measure the field intensity of television interference (TVI) for starting point in projection 20m place over the ground apart from limit ultra-high-tension power transmission line;
For strained angled tower, taking strained angled tower wire jumper over the ground subpoint as starting point, start to measure the field intensity of television interference (TVI).Around radius 400m is interior smooth to require test point, without the barrier such as high-lager building, large quantities of woods, far away apart from highway, factory etc.If anchor support has resident to reflect that television image is disturbed around, need test at resident's house owed by a citizen roof.
In described step 3, according to the television image carrier frequency frequency a0 of record, estimate the frequency range of television interference (TVI), if television interference (TVI) frequency, within the scope of 20～200MHz, adopts biconical antenna, if within the scope of 200MHz～2GHz, adopt log-periodic antenna.
Described step 4 comprises the following steps:
Step 4-1: select television interference (TVI) field intensity frequency and carry out interference field strength test;
China's standard television carrier spectrum is as accompanying drawing 2, TV signal is launching by radio broadcasting or when wire transmission, picture signal is adopted to vestigial sideband amplitudemodulation, residual fraction is 0.75MHz, transitional zone is 0.75MHz～1.25MHz, TV carrier signal frequency a0 is positioned at residual fraction, and the shared frequency band of each road TV programme is 8MHz.For China's TV signal, on 75MHz frequency, there is no TV signal carrier wave, therefore recommend 75MHz as test frequency, to assess the disturbed condition of the same frequency in different regions.If consider frequency decay, can increase voluntarily suitable frequency, be advisable to avoid TV signal frequency.
By the television image of recording, read the television carrier frequency being disturbed in conjunction with TV field strength meter, choose 75MHz as one of television interference (TVI) field intensity frequency, and using this frequency as carrying out field strength measurement with reference to evaluating frequency;
Step 4-2: the field intensity of measuring television interference (TVI);
Because the interference field strength that corona produces is very wide in scope, from the supreme G hertz of several megahertzes at zero point, and frequency spectrum is continuous spectrum, therefore produce overlapping in television carrier frequency place's undesired signal and TV signal itself, for this reason, need to adopt the undesired signal field intensity that acquisition is produced by line corona separately as Fig. 3.Concrete operation method is: a0(MHz) be television image carrier frequency frequency, select frequency a1=a0-1(MHz), a2=a0+1(MHz) frequency, carry out the measurement of television interference (TVI) field intensity, frequency a1(MHz) and a2(MHz) corresponding field intensity be respectively N1 and N2, because undesired signal frequency spectrum is continuous, the interference field strength N that obtains the generation of vision carrier frequency frequency a0 place is (N1+N2)/2.Utilize electromagnetic method to cut interference field strength N by the total intensity (S) of actual measurement and can obtain actual TV signal strength.
Finally should be noted that: above embodiment is only in order to illustrate that technical scheme of the present invention is not intended to limit, although the present invention is had been described in detail with reference to above-described embodiment, those of ordinary skill in the field are to be understood that: still can modify or be equal to replacement the specific embodiment of the present invention, and do not depart from any amendment of spirit and scope of the invention or be equal to replacement, it all should be encompassed in the middle of claim scope of the present invention.
Claims (8)
1. a method of testing for ultra-high-tension power transmission line television interference (TVI), is characterized in that: said method comprising the steps of:
Step 1: analyze the TV signal frequency range in tested area, and record the television image not being subject to before television interference (TVI);
Step 2: State selective measurements position;
Step 3: select antenna according to the frequency range of television interference (TVI);
Step 4: select television interference (TVI) field intensity frequency, and measure the field intensity of television interference (TVI).
2. the method for testing of ultra-high-tension power transmission line television interference (TVI) according to claim 1, is characterized in that: in described step 1, analyze the TV signal frequency range in tested area by TV field strength meter, and record the television image not being subject to before television interference (TVI).
3. the method for testing of ultra-high-tension power transmission line television interference (TVI) according to claim 2, is characterized in that: be not subject to the television image method for recording before television interference (TVI) as follows:
In the time that ultra-high-tension power transmission line is out of service or away from least distance of 500m of tested ultra-high-tension power transmission line, by antenna collection signal, signal is averagely allocated to TV field strength meter and televisor through divider, described TV field strength meter one road signal connects computer hard disc and records image, another road signal input televisor, produce television image with recording image quality with video camera, and record television vision carrier frequency frequency a0.
4. the method for testing of ultra-high-tension power transmission line television interference (TVI) according to claim 1, is characterized in that: in described step 2, select to be positioned near the straight line shelves sag minimum point that ultra-high-tension power transmission line is lower and near strained angled tower as measuring position.
5. the method for testing of ultra-high-tension power transmission line television interference (TVI) according to claim 4, it is characterized in that: the television interference (TVI) that ultra-high-tension power transmission line is produced is carried out distributed measurement, at least measure to limit mutually outside 100m, if there is resident in 100m, should near resident's television receiving antenna position, carry out distributed measurement.
6. the method for testing of ultra-high-tension power transmission line television interference (TVI) according to claim 5, it is characterized in that: distributed measurement method is: antenna is placed in to straight line shelves sag minimum point that ultra-high-tension power transmission line is lower over the ground on the vertical line of projection place and ultra-high-tension power transmission line, starts to measure the field intensity of television interference (TVI) for starting point in projection 20m place over the ground apart from limit ultra-high-tension power transmission line;
For strained angled tower, taking strained angled tower wire jumper over the ground subpoint as starting point, start to measure the field intensity of television interference (TVI).
7. the method for testing of ultra-high-tension power transmission line television interference (TVI) according to claim 3, it is characterized in that: in described step 3, according to the television image carrier frequency frequency a0 of record, estimate the frequency range of television interference (TVI), if television interference (TVI) frequency is within the scope of 20～200MHz, adopt biconical antenna, if within the scope of 200MHz～2GHz, adopt log-periodic antenna.
8. the method for testing of ultra-high-tension power transmission line television interference (TVI) according to claim 1, is characterized in that: described step 4 comprises the following steps:
Step 4-1: select television interference (TVI) field intensity frequency and carry out interference field strength test;
By the television image of recording, read the television carrier frequency being disturbed in conjunction with TV field strength meter, choose 75MHz as one of television interference (TVI) field intensity frequency, and using this frequency as carrying out field strength measurement with reference to evaluating frequency;
Step 4-2: the field intensity of measuring television interference (TVI);
A0 is television image carrier frequency frequency, selects frequency a1=a0-1, the frequency of a2=a0+1, carry out the measurement of television interference (TVI) field intensity, the field intensity that frequency a1 and a2 are corresponding is respectively N1 and N2, and because undesired signal frequency spectrum is continuous, the interference field strength N that obtains the generation of vision carrier frequency frequency a0 place is (N1+N2)/2.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104793065A (en) * | 2014-01-17 | 2015-07-22 | 国家电网公司 | Method of determining radio interference in AC transmission line crossed erection region |
| CN107861105A (en) * | 2017-10-24 | 2018-03-30 | 中国电力科学研究院有限公司 | A kind of test system and method for detecting transmission line of electricity and being influenceed on radar passive jamming |
| CN112114201A (en) * | 2020-09-20 | 2020-12-22 | 中国科学院武汉岩土力学研究所 | Method and system for improving settlement monitoring precision of transformer substation in strong electromagnetic field environment |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4888596A (en) * | 1988-04-19 | 1989-12-19 | Home Box Office, Inc. | Method and apparatus for determining earth station parameters such as rain margin, with attenuation pads |
| EP0798923A2 (en) * | 1989-07-14 | 1997-10-01 | Inline Connection Corporation | Video transmission and control system utilizing internal telephone lines |
| CN1551514A (en) * | 2003-05-09 | 2004-12-01 | 三星电子株式会社 | Device for removing interference signal with different characteristic and method for removing thereof |
| CN101287079A (en) * | 2008-05-21 | 2008-10-15 | 周颖平 | Transmission method, system and device for broadcast television signal |
| CN101335904A (en) * | 2007-06-29 | 2008-12-31 | Oss宽网股份有限公司 | Device, method and program for monitoring wired TV transmission path |
| CN101651485A (en) * | 2008-08-15 | 2010-02-17 | 百一电子股份有限公司 | Method for reducing intermodulation interference and signal receiver used by same |
| CN201945687U (en) * | 2010-12-27 | 2011-08-24 | 江西洪都航空工业集团有限责任公司 | Testing device for indoor anti-interference satellite navigation system |
| CN102435873A (en) * | 2011-09-09 | 2012-05-02 | 国网电力科学研究院 | Method for determining protection space between ultra-high-voltage DC (direct current) transmission line and wireless station |
| EP1618408B1 (en) * | 2003-04-25 | 2012-07-04 | Saab AB | Rfi suppression in sar |
-
2014
- 2014-03-25 CN CN201410112817.8A patent/CN103901282A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4888596A (en) * | 1988-04-19 | 1989-12-19 | Home Box Office, Inc. | Method and apparatus for determining earth station parameters such as rain margin, with attenuation pads |
| EP0798923A2 (en) * | 1989-07-14 | 1997-10-01 | Inline Connection Corporation | Video transmission and control system utilizing internal telephone lines |
| EP1618408B1 (en) * | 2003-04-25 | 2012-07-04 | Saab AB | Rfi suppression in sar |
| CN1551514A (en) * | 2003-05-09 | 2004-12-01 | 三星电子株式会社 | Device for removing interference signal with different characteristic and method for removing thereof |
| CN101335904A (en) * | 2007-06-29 | 2008-12-31 | Oss宽网股份有限公司 | Device, method and program for monitoring wired TV transmission path |
| CN101287079A (en) * | 2008-05-21 | 2008-10-15 | 周颖平 | Transmission method, system and device for broadcast television signal |
| CN101651485A (en) * | 2008-08-15 | 2010-02-17 | 百一电子股份有限公司 | Method for reducing intermodulation interference and signal receiver used by same |
| CN201945687U (en) * | 2010-12-27 | 2011-08-24 | 江西洪都航空工业集团有限责任公司 | Testing device for indoor anti-interference satellite navigation system |
| CN102435873A (en) * | 2011-09-09 | 2012-05-02 | 国网电力科学研究院 | Method for determining protection space between ultra-high-voltage DC (direct current) transmission line and wireless station |
Non-Patent Citations (1)
| Title |
|---|
| 谢辉春等: "特高压交流输电线有源电视干扰特性", 《高电压技术》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104793065A (en) * | 2014-01-17 | 2015-07-22 | 国家电网公司 | Method of determining radio interference in AC transmission line crossed erection region |
| CN107861105A (en) * | 2017-10-24 | 2018-03-30 | 中国电力科学研究院有限公司 | A kind of test system and method for detecting transmission line of electricity and being influenceed on radar passive jamming |
| CN112114201A (en) * | 2020-09-20 | 2020-12-22 | 中国科学院武汉岩土力学研究所 | Method and system for improving settlement monitoring precision of transformer substation in strong electromagnetic field environment |
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