CN104535456A - Novel sulfur hexafluoride gas density micro-water transmitter - Google Patents
Novel sulfur hexafluoride gas density micro-water transmitter Download PDFInfo
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- CN104535456A CN104535456A CN201410523107.4A CN201410523107A CN104535456A CN 104535456 A CN104535456 A CN 104535456A CN 201410523107 A CN201410523107 A CN 201410523107A CN 104535456 A CN104535456 A CN 104535456A
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- China
- Prior art keywords
- micro
- sulfur hexafluoride
- water
- gas density
- hexafluoride gas
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Abstract
The invention relates to a novel sulfur hexafluoride gas density micro-water transmitter used in sulfur hexafluoride electrical equipment. The transmitter is characterized by comprising a housing (1); a connecting joint (11) is mounted on the housing (1); the back end of the connecting joint (11) extends into the housing (1); a pressure sensor (2), a temperature sensor (3), and a micro-water sensor (4) are respectively mounted at the back end of the connecting joint (11) in the housing (1); the pressure sensor (2), the temperature sensor (3), and the micro-water sensor (4) are connected with a signal processing circuit, so as to output a current signal corresponding to a detected sulfur hexafluoride gas density value and a micro-water content. The density micro-water transmitter of the invention can effectively measure the sulfur hexafluoride gas density value and the micro-water value of the inside of sulfur hexafluoride electrical equipment when ambient temperature changes suddenly, and has higher monitoring precision.
Description
Technical field
The present invention relates to the micro-water transmitter of a kind of novel sulfur hexafluoride gas density that can be applied on sulfur hexafluoride electrical equipment.
Background technology
Sulfur hexafluoride electric product is widely used in power department, industrial and mining enterprises, facilitates the fast development of power industry.Ensure reliable and secure operation one of vital task becoming power department of sulfur hexafluoride electric product.As everyone knows, SF
6the effect of gas in high voltage electric equipment is arc extinguishing and insulation, SF in high voltage electric equipment
6if the micro-water content of gas exceeds standard and density reduces and will have a strong impact on SF
6the safe operation of high voltage electric equipment: 1) in the presence of some metal objects, SF
6gas high temperature more than 200 DEG C temperature can with water generation hydrolysis reaction, generate active HF and SOF2, etching insulative part and metalwork, and produce amount of heat, air chamber pressure is raised.2) when temperature reduces, too much moisture content may form condensation water, and insulating part surface insulation intensity is significantly reduced, and even flashover, causes serious harm.3) SF
6gas density is reduced to and to a certain degree will causes the forfeiture of insulation and arc extinction performance.Therefore grid operation codes mandatory provision, before putting equipment in service and run in all must to SF
6the bulk density and water content of gas carries out periodic detection.
For micro-water monitoring, off-line method is generally adopted to measure micro-water content at present: the portable dew point hygrometer of main employing carries out Site Detection, and it exists following defect: (1) is non real-time.Current power department adopts for general one year 2 times dew point hygrometer to detect SF
6the SF of electrical equipment
6gas micro water content, this is a kind of non real-time detection method, and it can not reflect the variation tendency that equipment runs, also cannot to SF
6the variation tendency of gas micro water content is predicted, the operation conditions of electrical equipment cannot be grasped, can not prevent in time and get rid of potential safety hazard, cannot by intelligent equipment repair based on condition of component standard, accurate evaluation, judgment device situation, be difficult to the repair based on condition of component realizing electrical equipment.(2) measurement limits by environment temperature.The operating ambient temperature of dew point hygrometer is-10 DEG C ~+50 DEG C.Meanwhile, different environment temperatures, its measurement range is different, the winter in the north and southern summer discomfort be fit to do on-the-spot SF
6gas micro water content is tested.Owing to being subject to the impact of weather and environment temperature, the data of detection only can reference.(3) time-consuming, bothersome, take gas.Adopt during dew point hygrometer test and need discharge SF for a long time
6gas, this is that before during measurement, 3-5 minute needs dry up sampling line because sampling line is containing wetly; In order to can SF be tested
6the SF of inside electric appliance
6gas micro water content, just needs a certain amount of SF
6out, the test of a usual complete and accurate about needs about 10 ~ 15 minutes to gas discharging.By standard sample gas flow, namely 30 ~ 40L/h calculates, and once test needs to discharge SF
6gas about 8 liters.So, after completing test several times, supplementary SF is just needed
6gas.In addition, also there is potential safety hazard in testing staff's operation lack of standardization.(4) high testing cost.Electric company has been the SF that testing need be equipped with reviewer, equipment, vehicle and high value
6gas.Rough calculation, the testing cost of sharing every year of each transformer station about tens thousand of to about tens0000 yuan.(5) field personnel is endangered healthy, atmosphere pollution.SF
6gas certainly as nontoxic gas, but can generate some toxic and harmfuls after pyroreaction, has great harm to the person.And SF
6gas is a kind of greenhouse gases, and international regulations directly can not enter air.
In order to ensure SF
6the reliability service of electrical equipment, improves the continuous reliability service ability of electric system, realizes presence and detects, monitors and failure prediction, become SF to its performance
6important research direction in electrical equipment application.Along with unattended operation transformer station is to the requirement of remote control, remote measurement, on-line monitoring SF
6the SF of electrical equipment
6gas density value and micro-water content have very important practical significance.Along with unattended operation transformer station is constantly strengthened, so to SF to networking, digitizing future development and the requirement to remote control, remote measurement
6the SF of electrical equipment
6the on-line monitoring of gas density and micro-water content state has important practical significance.Because the measurement of density and micro-water to external world temperature variation is also comparatively responsive.In the course of the work, the shell of existing micro-water-mass density transmitter is generally metal shell, and its heat conductivility is higher.Be installed in the process of outdoor use by micro-water-mass density transmitter, the change of ambient temperature can be transmitted to micro-water-mass density transmitter inside, by inaccurate for the measurement causing transmitter to micro-water, density by metal shell rapidly.
Summary of the invention
The object of this invention is to provide the micro-water transmitter of novel sulfur hexafluoride gas density that a kind of Acclimation temperature ability is strong, precision is high,
The micro-water transmitter of a kind of novel sulfur hexafluoride gas density, its special feature is: comprise housing, on the housing jointing is installed and the rear end of this jointing stretches in housing, the rear end of the jointing in this housing is separately installed with pressure transducer, temperature sensor and micro-water sensor, this pressure transducer, temperature sensor are connected with signal processing circuit with micro-water sensor, thus can export the current signal corresponding with micro-water content to the sulfur hexafluoride gas density value detected.
Wherein current signal is 4-20mA.
Its middle shell forms by three layers, and wherein internal layer adopts stainless steel material, and middle layer adopts thermal insulation material, outer employing stainless steel material.
Wherein thermal insulation material is pottery, plastics or sponge.
Wherein signal processing circuit comprises the amplifying circuit, single-chip microcomputer, digital analog converter, voltage current adapter and the electric current galvanostat that connect successively.
The rear end of the jointing wherein in housing is provided with printed circuit board (PCB), and described signal processing circuit is located on this printed circuit board (PCB).
Sulfur hexafluoride gas density of the present invention micro-water transmitter is owing to have employed above technical scheme, make it compared with prior art, there is following obvious advantage and disadvantage: because the housing of the micro-water transmitter of density forms by three layers, wherein internal layer is that stainless steel material is made, middle layer is that thermal insulation material is made, and outer is made for stainless steel material.So, density of the present invention micro-water transmitter can effectively measure the sulfur hexafluoride gas density of sulfur hexafluoride electrical equipment inside and micro-water number when environment temperature is suddenlyd change, make its monitoring accuracy higher.
Accompanying drawing explanation
Accompanying drawing 1 is structural representation of the present invention;
Accompanying drawing 2 is the schematic diagram of signal processing circuit in the present invention.
Embodiment
As shown in Figure 1, 2, the present invention is the micro-water transmitter of a kind of novel sulfur hexafluoride gas density, comprise housing 1, this housing 1 is provided with jointing 11 and the rear end of this jointing 11 stretches in housing 1, the rear end of the jointing 11 in this housing 1 is separately installed with pressure transducer 2, temperature sensor 3 and micro-water sensor 4, this pressure transducer 2, temperature sensor 3 are connected with signal processing circuit with micro-water sensor 4, thus can export the 4-20mA standard current signal corresponding with micro-water content to the sulfur hexafluoride gas density value detected.
Its middle shell 1 forms by three layers, and wherein internal layer 31 adopts stainless steel material, and middle layer 32 adopts thermal insulation material, and outer 33 adopt stainless steel material, and this thermal insulation material is pottery, plastics or sponge.Signal processing circuit comprises the amplifying circuit 5, single-chip microcomputer 6, digital analog converter 8, voltage current adapter 9 and the electric current galvanostat 10 that connect successively in addition, the rear end of the jointing 11 specifically in housing 1 is provided with printed circuit board (PCB) 12, and described signal processing circuit is located on this printed circuit board (PCB) 12.
In order to solve the problems referred to above that prior art exists, the invention provides the micro-water transmitter of strong, that precision the is high sulfur hexafluoride gas density of a kind of Acclimation temperature ability, for density and the micro-water content of sulfur hexafluoride gas in control & monitor airtight container, and for the Leakage Gas situation occurred in sulfur hexafluoride electrical equipment and micro-water content, send alerting signal and block signal in time, contribute to realizing SF simultaneously
6the SF of electrical equipment
6the on-line monitoring of gas density and micro-water, for ensureing that electric power safety plays a role.The present invention includes housing 1 and be arranged at pressure transducer 2, temperature sensor 3, micro-water sensor 4, amplifying circuit 5, single-chip microcomputer 6, power module 7, digital analog converter 8, voltage current adapter 9, the electric current galvanostat 10 in housing 1.Density of the present invention micro-water transmitter gathers pressure, temperature and micro-water signal by pressure transducer 2, temperature sensor 3, micro-water sensor 4, (this process adopts existing routine techniques means, such as, by the SF under formulae discovery or inquiry relevant temperature pressure condition to convert density value and micro-water content to through single-chip microcomputer 6 process
6density data can obtain), after the process of digital analog converter 8, voltage current adapter 9 and electric current galvanostat 10, can sulfur hexafluoride gas density value and micro-water content be converted to current signal, realize long-distance transmissions, and then contribute to the density and the micro-water content that realize on-line monitoring sulfur hexafluoride gas electrical equipment.
Embodiment 1:
In order to understand technical scheme of the present invention better, also by reference to the accompanying drawings the present invention is described in detail below by specific embodiment:
As Fig. 1 and Fig. 2, the present invention includes housing 1 and be arranged at pressure transducer 2, temperature sensor 3, micro-water sensor 4, amplifying circuit 5, single-chip microcomputer 6, power module 7, digital analog converter 8, voltage current adapter 9, electric current galvanostat 10, the jointing 11 in housing 1.Described housing 1 forms by three layers, and wherein internal layer 31 is made for stainless steel material, and middle layer 32 is made for thermal insulation material, and outer 33 are made for stainless steel material.
Micro-water sensor 4 and pressure transducer 2 sealing are fixed on after jointing 11, and are placed in inside internal layer 31.And amplifying circuit 5, single-chip microcomputer 6, power module 7, digital analog converter 8, voltage current adapter 9, electric current galvanostat 10 are fixed on printed circuit board (PCB) 12, and printed circuit board (PCB) 12 is positioned on the rear end of jointing 11, and is placed in inside internal layer 31.
The principle of work of sulfur hexafluoride gas density of the present invention micro-water transmitter is as follows:
By the measurement of pressure transducer 2, temperature sensor 3, micro-water sensor 4 pairs of pressure, temperature and micro-water contents, through amplifying circuit 5, the signal of the pressure measured, temperature and micro-water content is amplified, the signal of the pressure of this amplification, temperature and micro-water content, through the collection of single-chip microcomputer 6, obtains sulfur hexafluoride gas density P through single-chip microcomputer 6 internal calculation
20and micro-water content PPM, this sulfur hexafluoride gas density P20 and micro-water content PPM make it through the conversion of digital analog converter 8 P converting voltage signal form to
20Umicro-water content PPM
u, then again through the conversion of voltage current adapter 9, make the P of voltage signal form
20Uand PPM
uconvert the P of current signal form to
20Iand PPM
i, then through the effect of excess current galvanostat 10, make the sulfur hexafluoride gas density P of current signal
20Iwith micro-water content PPM
ican long-distance transmissions, and then realize density and the micro-water content of on-line monitoring sulfur hexafluoride gas electrical equipment.
In sum, sulfur hexafluoride gas density of the present invention micro-water transmitter forms by three layers due to the housing 1 of the micro-water transmitter of density, wherein internal layer 31 is made for stainless steel material, and middle layer 32 is made for thermal insulation material, and outer 33 are made for stainless steel material.So, density of the present invention micro-water transmitter can effectively measure the sulfur hexafluoride gas density of sulfur hexafluoride electrical equipment inside and micro-water number when environment temperature is suddenlyd change, make its monitoring accuracy higher, sulfur hexafluoride gas density value and micro-water content can be converted to corresponding current signal (4 ~ 20mA) accurately, realize long-distance transmissions, and then realize density and the micro-water content of on-line monitoring sulfur hexafluoride gas electrical equipment.
Those of ordinary skill in the art will be appreciated that, it is of the present invention that above embodiment is only used to explanation, and be not used as limitation of the invention, as long as in spirit of the present invention, all will drop in Claims scope of the present invention the change of the above embodiment, modification.
Claims (6)
1. the micro-water transmitter of novel sulfur hexafluoride gas density, it is characterized in that: comprise housing (1), this housing (1) is provided with jointing (11) and the rear end of this jointing (11) stretches in housing (1), the rear end of the jointing (11) in this housing (1) is separately installed with pressure transducer (2), temperature sensor (3) and micro-water sensor (4), this pressure transducer (2), temperature sensor (3) is connected with signal processing circuit with micro-water sensor (4), thus the current signal corresponding with micro-water content to the sulfur hexafluoride gas density value detected can be exported.
2. the micro-water transmitter of a kind of novel sulfur hexafluoride gas density as claimed in claim 1, is characterized in that: wherein current signal is 4-20mA.
3. the micro-water transmitter of a kind of novel sulfur hexafluoride gas density as claimed in claim 1, it is characterized in that: its middle shell (1) forms by three layers, wherein internal layer (31) adopts stainless steel material, middle layer (32) adopts thermal insulation material, and outer (33) adopt stainless steel material.
4. the micro-water transmitter of a kind of novel sulfur hexafluoride gas density as claimed in claim 3, is characterized in that: wherein thermal insulation material is pottery, plastics or sponge.
5. the micro-water transmitter of sulfur hexafluoride gas density as novel in the one in Claims 1-4 as described in any one, is characterized in that: wherein signal processing circuit comprises the amplifying circuit (5), single-chip microcomputer (6), digital analog converter (8), voltage current adapter (9) and the electric current galvanostat (10) that connect successively.
6. the micro-water transmitter of sulfur hexafluoride gas density as novel in the one in Claims 1-4 as described in any one, it is characterized in that: the rear end of the jointing (11) wherein in housing (1) is provided with printed circuit board (PCB) (12), and described signal processing circuit is located on this printed circuit board (PCB) (12).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410523107.4A CN104535456A (en) | 2014-09-30 | 2014-09-30 | Novel sulfur hexafluoride gas density micro-water transmitter |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410523107.4A CN104535456A (en) | 2014-09-30 | 2014-09-30 | Novel sulfur hexafluoride gas density micro-water transmitter |
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| CN104535456A true CN104535456A (en) | 2015-04-22 |
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|---|---|---|---|
| CN201410523107.4A Pending CN104535456A (en) | 2014-09-30 | 2014-09-30 | Novel sulfur hexafluoride gas density micro-water transmitter |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106644826A (en) * | 2016-12-13 | 2017-05-10 | 国网电力科学研究院武汉南瑞有限责任公司 | Device for monitoring micro-water density of SF6 on line |
| CN106706163A (en) * | 2016-12-15 | 2017-05-24 | 深圳供电局有限公司 | Temperature measuring device for measuring temperature of insulating gas in sulfur hexafluoride electrical equipment |
| CN109142139A (en) * | 2018-08-09 | 2019-01-04 | 江苏志能新能源科技有限公司 | One kind being used for the micro- water density on-Line Monitor Device of GIS sulfur hexafluoride gas |
| CN110567841A (en) * | 2019-09-04 | 2019-12-13 | 上海乐研电气有限公司 | Multifunctional gas density monitor and monitoring system |
| CN110567840A (en) * | 2019-09-04 | 2019-12-13 | 上海乐研电气有限公司 | Overvoltage-resistant gas density transmitter and monitoring system |
| CN110595941A (en) * | 2019-09-04 | 2019-12-20 | 上海乐研电气有限公司 | Medium-high voltage electrical equipment gas leakage monitor and monitoring system |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110567841A (en) * | 2019-09-04 | 2019-12-13 | 上海乐研电气有限公司 | Multifunctional gas density monitor and monitoring system |
| CN110567840A (en) * | 2019-09-04 | 2019-12-13 | 上海乐研电气有限公司 | Overvoltage-resistant gas density transmitter and monitoring system |
| CN110595941A (en) * | 2019-09-04 | 2019-12-20 | 上海乐研电气有限公司 | Medium-high voltage electrical equipment gas leakage monitor and monitoring system |
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Application publication date: 20150422 |