CN202916049U - Diffusion-type SF6 gas leakage monitoring device - Google Patents
Diffusion-type SF6 gas leakage monitoring device Download PDFInfo
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- CN202916049U CN202916049U CN 201220631363 CN201220631363U CN202916049U CN 202916049 U CN202916049 U CN 202916049U CN 201220631363 CN201220631363 CN 201220631363 CN 201220631363 U CN201220631363 U CN 201220631363U CN 202916049 U CN202916049 U CN 202916049U
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Abstract
The utility model provides a diffusion-type SF6 gas leakage monitoring device. The device comprises an infrared light source (1), a condenser (2), a temperature detector (3), a tapered optical collector (4), a measurement light filter (5), a reference light filter (6), a dual-channel infrared detector (7), a reflector (8), a reflector seat (9), a support (10), a filtering protection cover (11), a waterproof dustproof breathable film (12), a signal conditioning module (13), an A/D conversion module (14), a data processing module (15) and a light source driving module (16). The diffusion-type SF6 gas leakage monitoring device of the utility model is advantageous in continuous on-line monitoring of leaked SF6 gas, fast response, high precision, high reliability, waterproof and dustproof performance and no need of an air pump, and can be widely used in SF6 gas leakage monitoring systems.
Description
Technical field
The utility model belongs to SF
6Leakage Gas monitoring field is specifically related to adopt dual wavelength infrared monitoring principle and diffusion type structure, carries temperature compensation, has high precision SF6 Leakage Gas monitoring method and device that digital signal is exported.
Background technology
SF
6Gas obtains to use widely in electric system owing to have fabulous insulating property and arc extinction performance.But, SF
6The leakage of gas then can be polluted indoor environment, makes the operating personnel that enter the room, health even the life of making an inspection tour the maintainer be subject to serious threat.Therefore, good SF
6The gas leakage monitoring technology is subject to power industry practitioner's attention and pursuit.
At SF
6In the Leakage Gas monitoring field, the advantage of infrared monitoring technology just progressively gains public acceptance and payes attention to.Infrared-gas leakage monitoring technology is one of focus of at present research, possess highly sensitive, precision is high, good stability, have the advantages such as good selectivity, reliability is high, the life-span is long.
SF in electric system
6In the Leakage Gas monitoring, the normal method that adopts is suction-type SF
6Leakage monitoring technology, suction-type monitoring technology adopt aspiration pump that the gas to be measured of monitored area is sucked detector inside, and recycling measurement of correlation principle is to SF
6Concentration measure.Owing to need to adopt aspiration pump to bleed, gas needs to filter before entering air chamber, drying, so that apparatus structure is complicated, power consumption is larger, is unfavorable for carrying out continuous on-line monitoring, thereby has limited the application of this technology but in actual applications.
Summary of the invention
The purpose of this utility model be to provide a kind of can be to leaking SF
6Gas carries out that continuous on-line monitoring, response are fast, precision and the high diffusion type SF of reliability
6Leakage Gas monitoring method and device.This device has excellent water proof and dust proof performance, need not to use aspiration pump, can be widely used in SF
6In the Leakage Gas monitoring system.
The technical solution adopted in the utility model is: a kind of diffusion type SF
6The Leakage Gas monitoring device; this device comprises infrared light supply; condenser; hygrosensor; the taper optical collector; measure optical filter; the reference optical filter; the binary channels infrared eye; catoptron; mirror unit; support; filter protective cover; the water proof and dust proof ventilated membrane; the signal condition module; the A/D modular converter; data processing module; light source driver module; support with perforate forms the air chamber of a hollow; be close to one deck water proof and dust proof ventilated membrane on the support; the outside puts the filtration protective cover again; place the catoptron of gold-plated reflectance coating at an end of support; fix and link to each other with support by mirror unit; the other end arranges infrared light supply and binary channels infrared eye; the infrared light supply front end is provided with condenser; binary channels infrared eye front is provided with measures optical filter and reference optical filter; the front end of measuring optical filter and reference optical filter is provided with the taper optical collector, and is described for SF
6Measurement optical filter and the reference optical filter of Leakage Gas monitoring are super spike interference filter; hygrosensor places the position, space between air chamber condenser and the taper optical collector; circuit board is fixed on the support, and circuit board has shell protection and fixing, and and support between seal.
Wherein, circuit board comprises signal condition module, A/D modular converter, data processing module and light source driver module, the signal condition module is to reference signal and measuring-signal amplifies and filtering, the A/D modular converter converts analog electrical signal to digital signal that data processing module can receive, data processing module calculates gas concentration and externally output according to received digital signal, and light source driver module drives infrared light supply and sends stable infrared light.
Wherein, the centre wavelength of measuring optical filter is 10.55 μ m ± 80nm, and half-band width is 90nm ± 20nm, and the centre wavelength of reference optical filter is 3.95 μ m ± 40nm, and half-band width is 90 ± 20nm.
Theoretical according to infrared spectrum, asymmetric polarity molecule produces absorption owing to the rotation of internal dipole square, vibration etc. to the infrared light that passes gas molecule.Dissimilar gas molecule dipole moment is different, so that a kind of gas molecule has obvious absorption to the infrared light of specific wavelength.According to Lambert-Beer's law: I=I
0Exp (μ CL); Wherein I is output intensity, I
0Be incident intensity, C is gas concentration, and L is absorption length, and μ is the absorption coefficient of gas, can be rewritten as:
From above formula as can be known, when the absorption coefficient μ of absorption length L and gas is known, can be by measuring I and I
0Radiometer calculate the concentration of tested gas, I and I
0Ratio be called transmittance
In the practical application, because infrared light is easy to be subjected to many factors (such as temperature, mains fluctuations, light source ages etc.) impact, only can not be enough to the leakage of monitor gas by the decay of single light beam transmitted light intensity.Dual wavelength infrared monitoring principle increases a reference wavelength on the basis of single wavelength infrared monitoring, namely select tested gas that the wavelength at the strongest absorption peak place of infrared Absorption is the measurement wavelength, be reference wavelength and select another all gas to its wavelength that does not have receptivity, use electronic circuit corresponding to binary channels infrared eye, two optical filter and processing dual wavelength signal and algorithm to realize monitoring to Leakage Gas.Measure optical filter and the wavelength that the selection of reference optical filter sees through by one, after seeing through two optical filters, the variation of the infrared absorption energy of respective wavelength is reflected on the binary channels infrared eye, after processing and calculate by corresponding signal, determines existence and the concentration information of tested gas.When not having tested gas composition in the air chamber, what the binary channels infrared eye received is unabsorbed infrared light, and measuring-signal and reference signal equate; When having tested gas composition in the air chamber, the energy of measuring beam is absorbed, and the measuring-signal that detects is less than the signal of reference beam.If do not pass into SF
6Seeing through the light intensity of measuring passage during gas is I
0, the light intensity of reference channel is I '
0Pass into finite concentration SF
6The light intensity of measuring passage behind the gas is I, and the reference channel light intensity is I '; Transmittance T=I ' then
0I/I
0I '.Gas controlling device to determining has definite I
0And I '
0Value, as long as record I and I ' during monitoring, after processing by the signal of Circuits System, just can obtain tested SF
6The concentration information of gas.This reference is processed can eliminate effectively that flashing is fixed, the zero point drift of photoelectric device etc. is on the impact of measuring accuracy, so that the dual wavelength infrared monitoring has higher measuring accuracy.
According to above analysis, the utility model provides a kind of diffusion type SF
6The Leakage Gas the method for monitoring, the SF of leakage
6Gas is with after air mixes, through naturally diffusing into above-mentioned suction-type SF
6The Leakage Gas monitoring device; at first through filtering the large dust impurity of the preliminary filtering of ground floor filtration of protective cover; pass through again the thorough filtering moisture of water proof and dust proof ventilated membrane and dust; enter air chamber by the perforate on the support; in air chamber; drive infrared light supply by light source driver module and send infrared light; focusing through condenser; behind the collimating effect; gas in the directive air chamber; through after the tested gas absorption; be reflected after arriving on the catoptron; infrared light is again by air chamber and be absorbed; the infrared light that the taper optical collector comes mirror reflects converges; arrive the binary channels infrared eye through measuring optical filter and reference optical filter; two passages of binary channels infrared eye produce respectively the reference signal and the signal that comprises tested gas concentration information that comprise light source and environmental information; these two signals are by the amplification of signal condition module; filtering and A/D modular converter convert to after the digital signal; be input to data processing module; data processing module is removed the impact of light source and environment by Data Processing Platoon, according to the leakage SF that writes in advance
6The gas concentration computation model obtains tested SF
6The concentration of gas, meanwhile, the leakage SF that hygrosensor also will detect
6The temperature of gas is input to data processing module, and data processing module is again to leaking SF
6Gas concentration is carried out the temperature correction, thereby is leaked really SF
6The concentration of gas is with this SF
6Concentration is externally exported.
When wherein, data are processed in the described data processing module for leaking SF
6The characteristic of gas adopts the multi-point calibration method, sets up to leak SF
6The gas concentration computation model, timing signal is leaking SF
6Select a plurality of concentration point in the monitoring range ability, the preparation normal mixture obtains the variables D of an air inclusion concentration information to eliminate the impact of light source, according to D value and normal concentration X according to measuring voltage and reference voltage
0Corresponding relation between the value is set up and is leaked SF
6The gas concentration computation model writes the temperature information of this model and timing signal in the single-chip microcomputer storer in the lump, and during actual measurement, data processing module receives measuring voltage, reference voltage and three numerical value of temperature, calculates first and leaks SF
6Gas concentration information variable D is to get rid of light source fluctuation and the environmental impact that may exist, again according to the leakage SF that writes in advance
6The gas concentration computation model calculates corresponding concentration value, then carries out temperature compensation according to temperature, the leakage SF after being compensated
6Gas concentration, this concentration are tested leakage SF
6The actual concentration value of gas.
The utility model advantage compared with prior art is:
The utility model adopts dual wavelength infrared monitoring principle and diffusion type structure to carry out SF
6The concentration monitor of gas leakage, have be easy to realize that continuous on-line monitoring, response are fast, water proof and dust proof performance that precision and reliability are high, excellent and need not to use the advantage such as aspiration pump.The employing adopting dual wavelength infrared monitoring principle, select super spike interference filter to increase absorption length, taper optical collector as the employing of measurement optical filter, catoptron has strengthened the employing of receiving light power, water proof and dust proof ventilated membrane effectively have been avoided the interference of moisture dust and has carried out temperature compensation, correction, has effectively improved leakage SF
6The precision of gas-monitoring.According to leaking SF
6Computation model, demarcation and algorithm that gas characteristic is set up have guaranteed leakage SF
6The accuracy of gas-monitoring.The output of test result numeral carries temperature compensation etc., so that Output rusults is more accurate, convenient.
Diffusion type SF of the present utility model
6Leakage Gas monitoring method and device are electrical network SF
6Leakage Gas monitoring and the requisite gordian technique of reporting to the police, it applies the safety that improves the safe operation of electrical network and ensure the electric power practitioner being conducive to.
Description of drawings
Fig. 1 is the structural representation of device of the present utility model;
Among the figure: 1. infrared light supply, 2. condenser, 3. hygrosensor, 4. the taper optical collector, 5. measure optical filter, 6. the reference optical filter, 7. the binary channels infrared eye, 8. catoptron, 9. mirror unit, 10. support, 11. filters protective covers, 12. water proof and dust proof ventilated membranes, 13. signal condition modules, 14.A/D modular converter, 15. data processing modules, 16. light source driver modules;
Fig. 2 is 7 scaling method process flow diagrams;
Fig. 3 is flow chart of data processing figure of the present utility model.
Embodiment
Preferred embodiment of the utility model is that the infrared light that adopts parabolic concentrator that infrared light supply is sent focuses on and collimates, adopt spherical reflector and taper optical collector to realize infrared reflection of light and converge, the spherical reflector surface gold-plating receives enough light intensity to guarantee infrared eye.Adopt the water proof and dust proof ventilated membrane, can effectively avoid the impurity such as dust, moisture on the impact of optical element, can guarantee that again gas enters air chamber smoothly, to obtain faster response speed.
The structure of present embodiment as shown in Figure 1; support 10 with perforate forms the air chamber of a hollow; be close to one deck water proof and dust proof ventilated membrane 12 on the support 10; the outside puts again filters protective cover 11; place the catoptron 8 of gold-plated reflectance coating at an end of support 10, fixing and link to each other with support by mirror unit 9.The other end arranges infrared light supply 1 and binary channels infrared eye 7, infrared light supply 1 front end is provided with condenser 2, binary channels infrared eye 7 fronts are provided with measures optical filter 5 and reference optical filter 6, and the front end of measuring optical filter 5 and reference optical filter 6 is provided with taper optical collector 4.Described for SF
6Measurement optical filter 5 and the reference optical filter 6 of Leakage Gas monitoring are super spike interference filter, the centre wavelength of measuring optical filter 5 is 10.55 μ m ± 80nm, half-band width is 90nm ± 20nm, and the centre wavelength of reference optical filter 6 is 3.95 μ m ± 40nm, and half-band width is 90 ± 20nm.Hygrosensor 3 places the position, space between air chamber condenser 2 and the taper optical collector 4.Circuit board is fixed on the support 10; comprise signal condition module 13; A/D modular converter 14; data processing module 15 and light source driver module 16; 13 pairs of reference signals of signal condition module and measuring-signal amplifies and filtering; A/D modular converter 14 converts analog electrical signal to digital signal that data processing module 15 can receive; data processing module 15 follows the digital signal of accepting to calculate gas concentration and externally output; light source driver module 16 drives infrared light supply 1 and sends stable infrared light; circuit board has shell protection and fixing, and and support between seal.
During device work, the SF of leakage
6Gas is with after air mixes; through naturally diffusing into this device; at first through filtering the large dust impurity of the preliminary filtering of ground floor filtration of protective cover 11, pass through again water proof and dust proof ventilated membrane 12 thorough filtering moisture and dusts, enter air chamber by the perforate on the support 10.In air chamber, drive infrared light supply 1 by light source driver module 16 and send infrared light, focusing through condenser 2, behind the collimating effect, gas in the directive air chamber, through after the absorption of tested gas, arrive on the catoptron 8 and be reflected, infrared light is again by air chamber and be absorbed, taper optical collector 4 converges the infrared light that catoptron 8 reflections come, through measuring optical filter 5 and reference optical filter 6 arrival binary channels infrared eyes 7,7 two passages of binary channels infrared eye produce respectively the reference signal and the signal that comprises tested gas concentration information that comprise light source and environmental information, these two signals are by the amplification of signal condition module 13, filtering and A/D modular converter 14 convert to after the digital signal, be input to data processing module 15, data processing module 15 is removed the impact of light source and environment by Data Processing Platoon, according to the leakage SF that writes in advance
6The gas concentration computation model obtains tested SF
6The concentration of gas.Meanwhile, the hygrosensor 3 leakage SF that also will detect
6The temperature of gas is input to data processing module 15, and data processing module 15 is again to leaking SF
6Gas concentration is carried out the temperature correction, thereby is leaked really SF
6The concentration of gas is with this SF
6Concentration is externally exported.
Data processor is for SF
6The characteristic of gas, the method for employing multi-point calibration, present embodiment is selected seven calibration points, sets up to leak SF
6The gas concentration computation model, the flow process of 7 scaling methods is seen accompanying drawing 2.Timing signal is leaking SF
6Select 7 concentration point in the monitoring range ability, the preparation normal mixture, send into normal mixture after, according to measuring voltage V
mWith reference voltage V
RefObtain the variables D of an air inclusion concentration information, according to D value and normal concentration X
0Corresponding relation between the value is set up SF
6The gas concentration computation model writes this model in the single-chip microcomputer storer.During actual monitoring, data processing module 15 receives measuring voltage V
m, reference voltage V
RefAnd temperature T
mThree numerical value calculate first gas concentration information variable D, to get rid of light source fluctuation and the environmental impact that may exist, adopt look-up table to calculate corresponding concentration value X according to the concentration computation model that writes in advance again
mThen according to temperature T
mCalculate temperature compensation coefficient K and carry out temperature compensation, the gas concentration X after being compensated
T, this concentration is tested SF
6The actual concentration value of gas is externally exported this numerical value, and its flow process is seen accompanying drawing 3.
Claims (3)
1. diffusion type SF
6The Leakage Gas monitoring device; it is characterized in that: this device comprises infrared light supply (1); condenser (2); hygrosensor (3); taper optical collector (4); measure optical filter (5); reference optical filter (6); binary channels infrared eye (7); catoptron (8); mirror unit (9); support (10); filter protective cover (11); water proof and dust proof ventilated membrane (12); signal condition module (13); A/D modular converter (14); data processing module (15); light source driver module (16); support (10) with perforate forms the air chamber of a hollow; be close to one deck water proof and dust proof ventilated membrane (12) on the support (10); the outside puts again filters protective cover (11); place the catoptron (8) of gold-plated reflectance coating at an end of support (10); fixing and link to each other with support (10) by mirror unit (9); the other end arranges infrared light supply (1) and binary channels infrared eye (7); infrared light supply (1) front end is provided with condenser (2); binary channels infrared eye (7) front is provided with measures optical filter (5) and reference optical filter (6); the front end of measuring optical filter (5) and reference optical filter (6) is provided with taper optical collector (4), and is described for SF
6Measurement optical filter (5) and the reference optical filter (6) of Leakage Gas monitoring are super spike interference filter; hygrosensor (3) places the position, space between air chamber condenser (2) and the taper optical collector (4); circuit board is fixed on the support (10); circuit board has shell protection and fixing, and and support between seal.
2. a kind of diffusion type SF according to claim 1
6The Leakage Gas monitoring device, it is characterized in that: circuit board comprises signal condition module (13), A/D modular converter (14), data processing module (15) and light source driver module (16), signal condition module (13) is to reference signal and measuring-signal amplifies and filtering, A/D modular converter (14) converts analog electrical signal to digital signal that data processing module (15) can receive, data processing module (15) calculates gas concentration and externally output according to received digital signal, and light source driver module (16) drives infrared light supply (1) and sends stable infrared light.
3. a kind of diffusion type SF according to claim 1
6The Leakage Gas monitoring device is characterized in that: the centre wavelength of measuring optical filter (5) is 10.55 μ m ± 80nm, and half-band width is 90nm ± 20nm, and the centre wavelength of reference optical filter (6) is 3.95 μ m ± 40nm, and half-band width is 90 ± 20nm.
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|---|---|---|---|
| CN 201220631363 CN202916049U (en) | 2012-11-26 | 2012-11-26 | Diffusion-type SF6 gas leakage monitoring device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220631363 CN202916049U (en) | 2012-11-26 | 2012-11-26 | Diffusion-type SF6 gas leakage monitoring device |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102998061A (en) * | 2012-11-26 | 2013-03-27 | 中国科学技术大学 | Spreading type device and method for monitoring SF6 gas leakage |
| CN105334178A (en) * | 2015-11-26 | 2016-02-17 | 无锡拓能自动化科技有限公司 | Harmful gas monitoring system based on detection rectifying circuit |
| CN105510267A (en) * | 2015-11-26 | 2016-04-20 | 无锡拓能自动化科技有限公司 | Harmful gas monitoring system based on amplifying and filtering circuit |
| CN105510266A (en) * | 2015-11-26 | 2016-04-20 | 无锡拓能自动化科技有限公司 | Harmful gas monitoring system based on infrared absorption spectrum |
| CN107367478A (en) * | 2017-07-19 | 2017-11-21 | 常州合众电气有限公司 | Non-dispersive infrared optical sulfur hexafluoride gas concentration sensor |
| CN109444068A (en) * | 2018-12-29 | 2019-03-08 | 郎溪杰博电器科技有限公司 | A kind of Fuzzy Predictive Control analysis system of infrared carbon sulfur analyzer |
| CN109580432A (en) * | 2019-01-28 | 2019-04-05 | 贵州电网有限责任公司 | A kind of SF6/N2Mix electrical equipment leakage characteristics test method |
-
2012
- 2012-11-26 CN CN 201220631363 patent/CN202916049U/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102998061A (en) * | 2012-11-26 | 2013-03-27 | 中国科学技术大学 | Spreading type device and method for monitoring SF6 gas leakage |
| CN102998061B (en) * | 2012-11-26 | 2015-10-21 | 中国科学技术大学 | A kind of diffusion type SF6 Leakage Gas monitoring device and method |
| CN105334178A (en) * | 2015-11-26 | 2016-02-17 | 无锡拓能自动化科技有限公司 | Harmful gas monitoring system based on detection rectifying circuit |
| CN105510267A (en) * | 2015-11-26 | 2016-04-20 | 无锡拓能自动化科技有限公司 | Harmful gas monitoring system based on amplifying and filtering circuit |
| CN105510266A (en) * | 2015-11-26 | 2016-04-20 | 无锡拓能自动化科技有限公司 | Harmful gas monitoring system based on infrared absorption spectrum |
| CN107367478A (en) * | 2017-07-19 | 2017-11-21 | 常州合众电气有限公司 | Non-dispersive infrared optical sulfur hexafluoride gas concentration sensor |
| CN109444068A (en) * | 2018-12-29 | 2019-03-08 | 郎溪杰博电器科技有限公司 | A kind of Fuzzy Predictive Control analysis system of infrared carbon sulfur analyzer |
| CN109580432A (en) * | 2019-01-28 | 2019-04-05 | 贵州电网有限责任公司 | A kind of SF6/N2Mix electrical equipment leakage characteristics test method |
| CN109580432B (en) * | 2019-01-28 | 2020-06-02 | 贵州电网有限责任公司 | SF (sulfur hexafluoride)6/N2Method for testing leakage characteristics of hybrid electrical equipment |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130501 Termination date: 20151126 |