CN102997056B - Method for measuring distance between natural gas pipe leakage detecting sensors - Google Patents
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title claims abstract description 26
- 238000000034 method Methods 0.000 title claims abstract description 19
- 239000003345 natural gas Substances 0.000 title claims abstract description 13
- 239000013307 optical fiber Substances 0.000 claims abstract description 43
- 239000007789 gas Substances 0.000 claims description 12
- 230000003287 optical effect Effects 0.000 claims description 12
- 239000000835 fiber Substances 0.000 claims description 9
- 238000012545 processing Methods 0.000 claims description 9
- 238000012544 monitoring process Methods 0.000 abstract description 15
- 238000005259 measurement Methods 0.000 abstract description 10
- 238000005516 engineering process Methods 0.000 description 9
- 238000012360 testing method Methods 0.000 description 9
- 239000000523 sample Substances 0.000 description 7
- 238000009434 installation Methods 0.000 description 5
- 230000007613 environmental effect Effects 0.000 description 4
- 230000035945 sensitivity Effects 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
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- 230000000694 effects Effects 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 230000032258 transport Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000012806 monitoring device Methods 0.000 description 1
- 230000000644 propagated effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000001953 sensory effect Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
Abstract
The invention discloses a method for measuring distance between natural gas pipe leakage detecting sensors and relates to the technical field of mechanical vibration measurement, impact measurement and a pipe system. The method is used for measurement on the basis of an optical fiber sensed natural gas pipe leakage monitoring system; and a leakage signal is simulated at the position where the sensors are arranged, the signal transmitting time is estimated, and the distance between two sensors, i.e. the length of a pipe between the two sensors, is measured by combining the propagation speed of a leakage vibrating wave signal. The measurement on the pipe leakage detecting sensor distance is high in accuracy.
Description
Technical field
The present invention is a kind of gas pipeline leakage detecting sensor measuring space method.Relate to the measurement of mechanical vibration, the measurement of impact and pipe-line system technical field.
Background technique
At present, the pipeline overall length of building up in the world reaches 2,500,000 kilometers, and having surpassed railway total kilometrage becomes the main means of transportation of world energy sources, and the oil product of developed country and oil-producing area, the Middle East transports all realizes channelization.China's pipeline has also obtained very fast development in recent years, overall length is also over 70,000 kilometers, begun to take shape across thing, stretch from the north to the south, cover the whole nation, be communicated with the overseas large general layout of energy pipe network, pipeline transport becomes the major way of the allotment conveying of the strategic energy such as oil gas.
Pipeline, due to cross-regional wide, is subject to the reasons such as natural disaster, third party's breakage in installation, has caused more pipe leakage accident to occur.External pipe safety situation also allows of no optimist very much, and natural gas line big bang occurs in U.S. San Bruno city on September 9th, 2010, and blast causes long 51 meters a, hollow place of wide 9 meters on road surface.The pipeline of approximately 8 meters of one segment lengths, 76 centimetres of diameters is exploded heaven, flies out about 30 meters far away, and causes large-range fire disaster, causes 4 people dead, and 3 people are missing, and at least 52 people are injured, 4 hectares of burnt areas, and tens of houses are burnt.People's safety, environmental consciousness significantly promote in recent years, as the pipeline transportation safety problem of high risk industries, are also more and more paid attention to.
In ripe technology, for natural gas line leakage, only have sound wave monitoring method comparatively effective at present, but in order to improve the accuracy to the real-time of leakage monitoring and leak source location, the layout density that must add large sensor on pipeline, increase corresponding power supply, communications equipment simultaneously, cause system cost and installation and maintenance costly.
Along with the development of sensory technique is external as U.S. CSI, ATMOSI, European TERDeng company have carried out the research of SCADA leakage monitoring system, Sensornet company has also developed the leakage monitoring system based on distributed optical fiber temperature sensor, and portioned product has also been applied for patent protection at home; The units such as domestic University Of Tianjin, Tsing-Hua University, China Renmin People's Liberation Army Office Support Engineering Academy also further investigate the leakage monitoring method of pipeline.
Patent CN200410020046.6 discloses a kind of distribution type fiber-optic method for monitoring leak from oil gas pipe and monitoring device based on principle of interference.This monitoring system requires along pipeline, to lay side by side an optical cable at Near Pipelines, utilizes the optical fiber in optical cable to form a Fiber optic micro-vibration sensor.Patent CN200620119429, CN200610113044.0 are the pipeline leakage monitor based on Sagnac fibre optic interferometer, and patent CN200610072879.6 is a kind of pipeline leakage monitor and method based on distributed optical fiber acoustic sensing technology.
< < sensor and the 26th the 7th phase of volume of micro-system > > " the gas pipeline leakage detection method based on distributed fiberoptic sensor " discloses a kind of gas pipeline leak detecting device and method based on distributed fiberoptic sensor, it is to have installing optical fibres sensor on the pipeline body of certain intervals, the vibration wave signal that continuous real-time monitoring is propagated along pipeline body, the vibration wave signal gathering is carried out to analysing and processing, comprise type identification and vibration source location, wherein whether type identification is for to belong to leak type by the extraction and analysis of vibration wave feature being differentiated to it, according to vibration wave, propagate into the position at the time lag definite vibration of the velocity of propagation on pipeline body wave source place in conjunction with vibration wave of adjacent several optical fiber transducers simultaneously, the light intensity signal of sensor output is realized the determining of position of leakage point after photoelectric conversion.
CN1837674A discloses a kind of pipeline leakage testing device and method based on distributed optical fiber acoustic sensing technology.
US2006/0225507A1 discloses a kind of pipeline leakage testing device and method based on distributed fiberoptic sensor.
Above-mentioned technology all belongs to distributed optical fiber sensing monitoring method.But such technical monitoring is subject to the impact of the interference incident that pipeline occurs while leaking, have very high system false alarm rate, and antijamming capability is poor.
Summary of the invention
The object of the invention is to invent a kind of sensitivity and degree of accuracy is high, false alarm rate is low, be not subject to a kind of gas pipeline leakage detecting sensor measuring space method of such environmental effects.
In view of the sensitivity that above-mentioned a few class Leak testtion, monitoring technology exist is low, false alarm rate is high, be subject to the problems such as such environmental effects, the natural gas line leakage system based on quasi-distributed optical fiber interference sensing technology adopts high sensor and overcomes targetedly in conjunction with time domain, the frequency domain character of incident of leakage.
Thereby the natural gas line leakage system with the sensitivity of high leakage vibrating sensing is to have realized the raising of interferometer to the induction sensitivity of oscillating signal by increasing length and the space length of interferometer two pickup arms, aspect the inhibition that Environmental Random Vibration is disturbed, adopting the intelligent identification technology of leakage signal, random accidental vibration and sudden, persistency leakage signal have effectively been distinguished, and the leakage signal time delay of simultaneously obtaining in conjunction with adjacent a plurality of sensors, the location of having realized more accurately leakage point.
The present invention is that the natural gas line leakage system (seeing Fig. 1) based on Fibre Optical Sensor is measured.An optical fiber transducer is installed at a certain distance on pipeline body, a plurality of optical fiber transducers form an optical fiber transducer group, each optical fiber transducer group is received light source and the photodetector of receiving terminal with an optical fiber, photodetector output connects signals collecting and the puocessing module that comprises leakage signal identification and state event location function, and described signals collecting and puocessing module comprise that signal condition, signals collecting, processing unit, terminal show and external interface; The signal condition that connects photodetector output is exported serial connection, signals collecting and processing unit successively, and processing unit output has terminal to show and external interface.Signals collecting and puocessing module output connect microcomputer.Through the processing of signals collecting and puocessing module, the sensor group signal mixing based on frequency division multiplexing mode has been realized the demultiplexing of each sensor in sensor group, obtains original leakage vibration wave signal.
Pipe leakage sensor measuring space method is: in the buried pipeline with under on-the-spot equivalent environment, adopt identical simulated leakage signal generating mode to measure, at the position of sensor installation simulated leakage signal, carrying out time delay estimation, is that between two sensors, duct length is measured in conjunction with leaking the realization of vibration wave signal velocity to sensor interval.
When leak occurring, leak and excite pipeline to produce vibration wave, vibration wave is with speed V along pipe transmmision, and wherein two adjacent sensors are spaced apart setting value L, and establishing the time that signal is transmitted to sensor n is t
n, the time that is transmitted to sensor n+1 is t
n+1, the time that signal is transmitted to sensor n-1 is t
n-1, the time that is transmitted to sensor n+2 is t
n+2, have following formula to set up:
Unknown parameter (t wherein
n+1-t
n), (t
n-1-t
n+1), (t
n+2-t
n) and (t
n+2-t
n-1) signal that can receive by the several sensors of correspondence carries out relevant treatment and obtain, so just formed the repeatedly observation to the same unknown quantity of event occurrence positions X, it is poor that a plurality of sensors of combined continuous receive signal time, draw gas pipeline leakage sensor span, compare and only adopt the time difference measurements mode of two sensors to there is locating effect more accurately.When simulated leakage test point is chosen in to some sensing stations, by test simulation leakage signal, propagate into the required time of proximity sense, according to vibration wave, along the speed of pipe transmmision, can test out one by one the span of each sensor laying, after repeatedly measuring, carry out statistical average and eliminate measurement random error, can further improve the precision of sensor interval test.
Utilize with the common communications optical fibre in optical cable of oil and gas pipes laying in one ditch respectively as sending and receiving transmission fiber, pipe leakage optical fiber sensing probe is connected between transmitting-receiving transmission fiber by Optical multiplexing technology is parallel with one another, form light circuit, it is along the line that pipe leakage optical fiber sensing probe is evenly laid in pipeline, the optical fiber sensing system that formation can monitoring pipe road acoustic vibration.Utilize light source to each pipe leakage optical fiber sensing probe scanning, photoelectric conversion signal demodulation, extraction according to the distribution situation of pipe leakage optical fiber sensing probe to collection, the vibration information of realizing each pipe leakage optical fiber sensing probe obtains, detect analysis conduit leakage optical fiber sensing probe signal and judged whether that pipe leakage event occurs, the time delay of arrival that signal detected according to adjacent pipe leakage optical fiber sensing probe is realized the location to leakage point.
The be as the criterion pipeline leakage monitor of distributing optical fiber sensing of the present invention provides a system installation parameter accurately, the optical fiber transducer of usining without power supply is as the pick device of simulated leakage signal, utilize the signal remote transmission that realizes optical fibre vibration sensor with optical fiber and the Optical multiplexing technology of ditch laying with pipeline, and can multisensor combine and carry out propagation time test, make the accuracy of measurement at pipe leakage sensor interval higher.
Accompanying drawing explanation
Fig. 1 monitoring system of fiber optical sensing natural gas pipeline schematic diagram of device
Fig. 2 Fibre Optical Sensor natural gas line simulated leakage signal measuring sensor interval schematic diagram
Embodiment
In conjunction with the accompanying drawings and embodiments the present invention is further described, but should limit the scope of the invention with this.
Embodiment. this example is that the natural gas line leakage system (seeing Fig. 1) based on Fibre Optical Sensor is measured.Pipe leakage sensor measuring space method is: in the buried pipeline with under on-the-spot equivalent environment, adopt identical simulated leakage signal generating mode to measure, at the position of sensor installation simulated leakage signal, carrying out time delay estimation, is that between two sensors, duct length is measured in conjunction with leaking the realization of vibration wave signal velocity to sensor interval.
When measuring natural gas line leakage system sensor interval, after artificial generation simulated leakage signal (seeing Fig. 2), simulated leakage signal excitation pipeline produces vibration wave, vibration wave with speed V along pipe transmmision, wherein two adjacent sensors are spaced apart setting value L, and establishing the time that signal is transmitted to sensor n is t
n, the time that is transmitted to sensor n+1 is t
n+1, the time that signal is transmitted to sensor n-1 is t
n-1, the time that is transmitted to sensor n+2 is t
n+2, have following formula to set up:
Unknown parameter (t wherein
n+1-t
n), (t
n-1-t
n+1), (t
n+2-t
n) and (t
n+2-t
n-1) signal that can receive by the several sensors of correspondence carries out relevant treatment and obtain, so just formed the repeatedly observation to the same unknown quantity of event occurrence positions X, it is poor that a plurality of sensors of combined continuous receive signal time, draw gas pipeline leakage sensor span, compare and only adopt the time difference measurements mode of two sensors to there is locating effect more accurately.
This routine light source adopts the narrow cable and wide optical fiber laser of 100kHZ live width.
This example is through test of many times, by being installed on tube wall, leakage vibration sensing interferometric sensor can realize the monitoring to any disturbance behavior along pipe transmmision, velocity of propagation through to leakage signal in the test of simulated leakage signal propagation time and pipeline, can realize determining of sensor interval.
Claims (1)
1. a gas pipeline leakage detecting sensor measuring space method, is characterized in that it is that natural gas line leakage system based on Fibre Optical Sensor is measured; An optical fiber transducer is installed at a certain distance on pipeline body, a plurality of optical fiber transducers form an optical fiber transducer group, each optical fiber transducer group is received light source and the photodetector of receiving terminal with an optical fiber, photodetector output connects signals collecting and the puocessing module that comprises leakage signal identification and state event location function, and described signals collecting and puocessing module comprise that signal condition, signals collecting, processing unit, terminal show and external interface; The signal condition unit output that connects photodetector output is connected in series signals collecting and processing unit successively, and processing unit output has terminal to show and external interface; Signals collecting and puocessing module output connect microcomputer; Through the processing of signals collecting and puocessing module, the optical fiber transducer group signal mixing based on frequency division multiplexing mode has been realized the demultiplexing of each optical fiber transducer in optical fiber transducer group, obtains original leakage vibration wave signal; At the position of installing optical fibres sensor simulated leakage signal, carrying out time delay estimation, is that between two optical fiber transducers, duct length is measured in conjunction with leaking the realization of vibration wave signal velocity to optical fiber transducer interval;
When leak occurring, leak and excite pipeline to produce vibration wave, vibration wave is with speed v along pipe transmmision, and wherein two adjacent optical fiber transducers are spaced apart setting value L, and establishing the time that signal is transmitted to optical fiber transducer n is t
n, the time that is transmitted to optical fiber transducer n+1 is t
n+1, the time that signal is transmitted to optical fiber transducer n-1 is t
n-1, the time that is transmitted to optical fiber transducer n+2 is t
n+2, have following formula to set up:
Unknown parameter (t wherein
n+1-t
n), (t
n-1-t
n+1), (t
n+2-t
n) and (t
n+2-t
n-1) signal that can receive by the several sensors of correspondence carries out relevant treatment and obtain, so just formed the repeatedly observation to the same unknown quantity of event occurrence positions X, it is poor that a plurality of optical fiber transducers of combined continuous receive signal time, draws gas pipeline leakage sensor span.
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Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105509979B (en) * | 2016-01-11 | 2019-01-04 | 山东省科学院激光研究所 | Monitoring leak from oil gas pipe positioning system and method based on optical fiber suction wave |
| CA3047747A1 (en) * | 2016-12-19 | 2018-06-28 | Vionx Energy Corporation | Systems and methods for electrolyte storage and detecting faults in flow batteries |
| CN108398211B (en) * | 2018-01-15 | 2020-01-10 | 中北大学 | Distributed optical fiber water leakage sensor based on external source positioning and water leakage detection method |
| CN108387889B (en) * | 2018-04-04 | 2024-01-16 | 广东电网有限责任公司 | Device for determining longitudinal distance of power cable on ground |
| CN112856250A (en) * | 2021-02-01 | 2021-05-28 | 苏州思萃融合基建技术研究所有限公司 | Water supply pipeline leakage positioning method |
| CN112856249A (en) * | 2021-02-01 | 2021-05-28 | 苏州思萃融合基建技术研究所有限公司 | Urban water supply pipe network leakage monitoring method |
| CN113790401B (en) * | 2021-08-30 | 2023-08-29 | 长江勘测规划设计研究有限责任公司 | Intelligent detection positioning method for leakage of ultra-long deep-buried water-conveying tunnel |
| CN115855070B (en) * | 2023-03-01 | 2023-04-28 | 东莞先知大数据有限公司 | Water pipe water leakage detection method and device, electronic equipment and storage medium |
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| CN1837674A (en) * | 2006-04-14 | 2006-09-27 | 北京工业大学 | Apparatus and method for monitoring pipeline leakage based on distributed optical fiber acoustic sensing technology |
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| WO2004063623A1 (en) * | 2003-01-13 | 2004-07-29 | Pure Technologies Ltd. | Pipeline monitoring system |
| CN1837674A (en) * | 2006-04-14 | 2006-09-27 | 北京工业大学 | Apparatus and method for monitoring pipeline leakage based on distributed optical fiber acoustic sensing technology |
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Effective date of registration: 20170320 Address after: 100007 Beijing, Dongzhimen, North Street, No. 9, No. Patentee after: China National Petroleum Corporation Patentee after: China Petroleum Pipeline Bureau Engineering Co., Ltd. Address before: 100007 Dongcheng District, Dongzhimen, China, North Street, No. 9 Oil Mansion, No. Patentee before: China National Petroleum Corporation Patentee before: China Petroleum and Natural Gas Pipeline Bureau |