CN106652365A - Method for acquiring leak state and concentration of natural gas by setting dead zone and biasing - Google Patents
Method for acquiring leak state and concentration of natural gas by setting dead zone and biasing Download PDFInfo
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- CN106652365A CN106652365A CN201710043344.4A CN201710043344A CN106652365A CN 106652365 A CN106652365 A CN 106652365A CN 201710043344 A CN201710043344 A CN 201710043344A CN 106652365 A CN106652365 A CN 106652365A
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- leak sensor
- natural gas
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- control mcu
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title claims abstract description 96
- 239000003345 natural gas Substances 0.000 title claims abstract description 48
- 238000000034 method Methods 0.000 title claims abstract description 27
- 239000007789 gas Substances 0.000 claims abstract description 36
- 238000012545 processing Methods 0.000 claims abstract description 18
- 230000005540 biological transmission Effects 0.000 claims description 15
- 238000004891 communication Methods 0.000 claims description 10
- 238000007689 inspection Methods 0.000 claims description 9
- 230000008569 process Effects 0.000 claims description 8
- 230000002159 abnormal effect Effects 0.000 claims description 7
- 230000008859 change Effects 0.000 claims description 4
- 230000007704 transition Effects 0.000 claims description 3
- 230000005611 electricity Effects 0.000 claims description 2
- 238000012360 testing method Methods 0.000 claims description 2
- 238000001514 detection method Methods 0.000 abstract description 12
- 238000013461 design Methods 0.000 abstract description 2
- 238000012544 monitoring process Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical group [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 239000000567 combustion gas Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B21/00—Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
- G08B21/02—Alarms for ensuring the safety of persons
- G08B21/12—Alarms for ensuring the safety of persons responsive to undesired emission of substances, e.g. pollution alarms
- G08B21/16—Combustible gas alarms
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
- G08B29/02—Monitoring continuously signalling or alarm systems
- G08B29/04—Monitoring of the detection circuits
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- Environmental & Geological Engineering (AREA)
- General Health & Medical Sciences (AREA)
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- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Emergency Alarm Devices (AREA)
- Alarm Systems (AREA)
Abstract
The invention discloses a method for acquiring the leak state and concentration of natural gas by setting a dead zone and biasing. A host and a leak sensor are adopted; and mainly adopted are a gas-sensitive element on the leak sensor, the host, a power system, an ADC processing module, a main control unit (MCU), a numerical display, a sound-light alarm, an external communicator and a key. The method for acquiring the leak state and concentration of natural gas by setting a dead zone and biasing is reasonable in design, high in detection accuracy and high in detection efficiency, and has a self-checking function and a multi-directional detection function.
Description
Technical field
It is especially a kind of with arranging dead band and biasing collection natural gas leaking state and dense the present invention relates to natural gas field
The method of degree.
Background technology
Natural gas is one of safer combustion gas, and it does not contain carbon monoxide, lta yet, once leakage, immediately can
Diffuse up, be difficult accumulation and form explosive gas, security is of a relatively high compared with for other combustion bodies.Natural gas fires as automobile
Material, with unit calorific value it is high, exhaust pollution is little, supply is reliable, the low advantage of price, it has also become world's clean fuel for vehicle
Exhibition direction, and gas-fueled vehicles have then become new-energy automobiles with fastest developing speed, that usage amount is most.Environmental protection natural gas is one
Environmental clean high-grade energy, hardly sulfur-bearing, dust and other harmful substances are planted, generation carbon dioxide is less than other during burning
Fossil fuel, causes greenhouse effects relatively low, thus can fundamentally improve environmental quality, using the vehicle of gas fuel, by
In the severe use environment of vehicle, it is possible to that the situation of natural gas leaking, GB 7258-2012 occurs in use
《Automobile safety running technology condition》In require that gas-fueled vehicles have to install additional vehicle-mounted natural gas leaking warning system, this is specially
Being used in natural gas leaking warning system state that leak sensor is carried out between leak sensor and main frame and information is carried out
Use during interaction, it is in-car in the vehicle using gas fuel, natural gas leaking warning system is typically all installed, system typically by
Main frame, cable, multiple leak sensors composition, adopt cable connection between main frame and leak sensor.Leak sensor is being adopted
Collect natural gas leaking, and more than alarm limits after, say that alarm signal passes to main frame by cable, by main frame carry out showing with
Report to the police etc., the signal of leak sensor output is regular tap amount signal, only leakage alarm, two states of not reporting to the police, main frame
The whether damage of leak sensor cannot be detected, if there is exception, cannot also collect leak sensor sensing point natural
Gas concentration, and then natural gas leaking concentration and subsequent treatment are shown in real time, because leak sensor damages the state that cannot be reported to the police
It is identical with the state that leak sensor is not reported to the police, in the case where leak sensor is damaged, if occurred at the place of being detected
Natural gas leaking state, main frame cannot detect leakage, cannot also carry out sound and light alarm, there is huge potential safety hazard.
The content of the invention
For solve the above problems it is an object of the invention to provide detection efficiency it is high, can be with comprehensive detection, with self-inspection work(
The high method for gathering natural gas leaking state and concentration with setting dead band and biasing of energy and accuracy rate.
For the technical scheme that solves the above problems：One kind setting dead band and biasing collection natural gas leaking state
And the method for concentration, including main frame and leak sensor, it is described including：
Leak sensor, leak sensor is provided with several, and leak sensor is mainly used in gathering natural gas gas sensitive signal, and will
Gas sensitive signal is transformed into discernible signal, is broadly divided into；
Gas sensor, for receiving the natural gas of leakage, and is transferred to processor of single chip computer by gas sensitive signal,
Processor of single chip computer, is connected with the gas sensor by gas sensitive signal, and processor of single chip computer is received after gas sensitive signal,
By ADC process gas sensitive signal is transformed into data signal, by DAC process by digital signal transition into voltage signal, and
Voltage signal is transferred on main frame, the power supply on processor of single chip computer is connected with the power-supply system on main frame,
Main frame is processing system, is broadly divided into：Power-supply system, ADC processing modules, main control MCU, numerical value show, sound and light alarm, right
Outer communication and button：
Power-supply system, is that the power supply in main control MCU and leak sensor is powered；
ADC processing modules, are connected with main control MCU, are to receive the voltage signal sent from leak sensor, are transformed into numeral
Signal；
Main control MCU, the data signal that will be transmitted in ADC processing modules, is identified, to make instruction；
Numerical value shows, is connected with main control MCU, is the data signal that will change in ADC processing modules, is shown, can be intuitively
See whether natural gas leaking situation and leak sensor work are abnormal；
Sound and light alarm, is connected with main control MCU, is whether the natural gas made to main control MCU leaks and respond, if natural gas
Leakage can then send sound and light alarm；
Externally communication, be connected with main control MCU, externally communication can with external bluetooth, wirelessly；
Button, for arranging natural gas leaking limit value, main control MCU can send instruction after limit value is reached.
Preferably, the leak sensor transmission signal is divided into：
Leak sensor,（By taking the conventional 5V power supply signals of tradition as an example）Leak sensor 1.5V is set used as reference offset electricity
Pressure, is also 0%LEL voltages, and 4.0V is used as 100%LEL output voltages；
When leak sensor exports V<VL(0.7V) or leak sensor V>VH(4.3V) when, it is believed that leak sensor self-inspection is different
Often；（VL For output voltage minimum of a value, VHFor output voltage maximum）
When leak sensor is exported in concentration of natural gas limit value<V<During 4.0V, main frame thinks the test point superleak, sends acousto-optic
Alarm signal.
Preferably, the main frame connects several leak sensors by transmission circuit.
Preferably, the detecting step is：
Gas sensor detects gas sensitive signal, and gas sensitive signal is transferred into processor of single chip computer；
ADC on processor of single chip computer is processed and for gas sensitive signal to be transformed into data signal, and data signal is transformed into through DAC process
Voltage signal, and be transported on main frame by transmission circuit；
Voltage signal is transformed into data signal by the ADC processing modules of main frame, is processed in digital data transmission to main control MCU and is divided
Analysis, when data signal exceed limit value when, sound and light alarm can be responded, when data signal is too low or or it is too high when, main control MCU meeting
Judge, assert leak sensor self-inspection exception, remind driver to be detected.
Beneficial conditions：
The invention provides a kind of method with dead band and biasing collection natural gas leaking state and concentration is arranged, reasonable in design,
Detection accuracy is high, detection efficiency is high and with self-checking function and can be in the method for multi-faceted detection.
Description of the drawings
Fig. 1 is the circuit structure diagram of the present invention.
Fig. 2 is that the output voltage of the present invention and concentration relationship change represent intention.
Specific embodiment
A kind of method with dead band and biasing collection natural gas leaking state and concentration is arranged, including master as shown in Figure 1, 2
Machine and leak sensor, it is described including：
Leak sensor, leak sensor is provided with several, and leak sensor is mainly used in gathering natural gas gas sensitive signal, and will
Gas sensitive signal is transformed into discernible signal, is broadly divided into；
Gas sensor, for receiving the natural gas of leakage, and is transferred to processor of single chip computer by gas sensitive signal,
Processor of single chip computer, is connected with the gas sensor by gas sensitive signal, and processor of single chip computer is received after gas sensitive signal,
By ADC process gas sensitive signal is transformed into data signal, by DAC process by digital signal transition into voltage signal, and
Voltage signal is transferred on main frame, the power supply on processor of single chip computer is connected with the power-supply system on main frame,
Main frame is processing system, is broadly divided into：Power-supply system, ADC processing modules, main control MCU, numerical value show, sound and light alarm, right
Outer communication and button：
Power-supply system, is that the power supply in main control MCU and leak sensor is powered；
ADC processing modules, are connected with main control MCU, are to receive the voltage signal sent from leak sensor, are transformed into numeral
Signal；
Main control MCU, the data signal that will be transmitted in ADC processing modules, is identified, to make instruction；
Numerical value shows, is connected with main control MCU, is the data signal that will change in ADC processing modules, is shown, can be intuitively
See whether natural gas leaking situation and leak sensor work are abnormal；
Sound and light alarm, is connected with main control MCU, is whether the natural gas made to main control MCU leaks and respond, if natural gas
Leakage can then send sound and light alarm；
Externally communication, be connected with main control MCU, externally communication can with external bluetooth, wirelessly；
Button, for arranging natural gas leaking limit value, main control MCU can send instruction after limit value is reached.
The content of this patent will leak out the regular tap amount signal of transmission in transmission circuit between sensor and main frame, be changed to
Transmission analog signal, for transmitting more information, the analog voltage signal that main frame can send out according to leak sensor,
The state of leak sensor is determined, it is also possible to collect the natural gas leaking concentration of leak sensor output, for solving above
The security hidden trouble mentioned, including：
Leak sensor abnormal signal is transmitted；
Leak sensor normal signal is transmitted；
Leak sensor concentration value is transmitted；
Leak sensor leakage alarm state is transmitted.
Implementation method：
As a example by transmit conventional 5V power supply signals, leak sensor output voltage is V：
a）The transmission of leak sensor abnormal signal and monitoring：
Realize the transmission of leak sensor abnormal signal and monitor using upper and lower dead band method is arranged：
Work as V<VL(can set, such as 0.7V) or V>VHWhen (can set, such as 4.3V), it is believed that leak sensor self-inspection exception.
As V=0V, it is believed that leak sensor is connectionless or damages, and is also a kind of leak sensor abnormal conditions.
b）Leak sensor normal signal is transmitted and monitoring；
The transmission and monitoring of leak sensor normal signal are realized using the method for arranging fixed bias value：
Leak sensor only has under normal conditions, stable initial voltage value Vo could be exported, so when V=Vo (can
Setting, such as 1.5V), it is believed that leak sensor self-inspection is normal, and can consider that leakage point concentration is 0%LEL.
c）Leak sensor concentration value is transmitted；
Leak sensor leakage concentration value transmission is realized using superposed simulation signal method in fixed bias value is arranged：
When V=Vo (can set, such as 1.5V), it is believed that leak sensor self-inspection is normal, and leakage point concentration is 0%LEL；Work as V=
4.0V（Can set）When, it is believed that leak sensor exports 100%LEL, linear scale output, and follows concentration value and magnitude of voltage
Equation rule：Concentration value deducts 0.6 equal to 0.4 magnitude of voltage.
It is different according to the warning concentration of setting, alarm condition can be determined according to leak sensor output voltage, such as with 20%
LEL（Can be required according to user, set variable concentrations value）Report to the police and adjust：
When leak sensor output voltage is 2.0V, correspondence 20%LEL, when leak sensor output voltage>During 2.0V, leakage is passed
Sensor is in alarm condition, and main frame can carry out sound and light alarm.
As leak sensor output voltage 2.0V< V<During 4.0V, main frame thinks leakage point superleak, sends sound and light alarm letter
Number;Main frame prompting can carry out sound and light alarm, and for reminding effect, leak sensor is natural gas leaking warning leakage sensing
Device, main frame can gather the signal of several leak sensors, so can be with comprehensive detection, the external communication on main frame, can
To support the equipment such as wireless, bluetooth, can be very high with remote monitoring, detection efficiency, button is used for the concentration setting that setting is reported to the police
With other operations, when leak sensor output voltage is transmitted as 0V, leak sensor self-inspection exception, main frame shows leakage sensing
Device breaks down, and carries out sound and light alarm prompting, it is an object of the invention to provide detection efficiency it is high, can with comprehensive detection, have
The method of the high usage frequency voltage transformation collection natural gas leaking state of self-checking function and accuracy rate and concentration.
Specific embodiment described herein is only to explanation for example of the invention.The technology of the technical field of the invention
Personnel can be made various modifications to described specific embodiment or supplement or substituted using similar mode, but not
The spirit of the present invention can be deviateed or surmount scope defined in appended claims.
Claims (4)
1. a kind of method with dead band and biasing collection natural gas leaking state and concentration is arranged, including main frame and leakage sensing
Device, it is characterised in that it is described including：
Leak sensor, leak sensor is provided with several, and leak sensor is mainly used in gathering natural gas gas sensitive signal, and will
Gas sensitive signal is transformed into discernible signal, is broadly divided into；
Gas sensor, for receiving the natural gas of leakage, and is transferred to processor of single chip computer by gas sensitive signal,
Processor of single chip computer, is connected with the gas sensor by gas sensitive signal, and processor of single chip computer is received after gas sensitive signal,
By ADC process gas sensitive signal is transformed into data signal, by DAC process by digital signal transition into voltage signal, and
Voltage signal is transferred on main frame, the power supply on processor of single chip computer is connected with the power-supply system on main frame,
Main frame is processing system, is broadly divided into：Power-supply system, ADC processing modules, main control MCU, numerical value show, sound and light alarm, right
Outer communication and button：
Power-supply system, is that the power supply in main control MCU and leak sensor is powered；
ADC processing modules, are connected with main control MCU, are to receive the voltage signal sent from leak sensor, are transformed into numeral
Signal；
Main control MCU, the data signal that will be transmitted in ADC processing modules, is identified, to make instruction；
Numerical value shows, is connected with main control MCU, is the data signal that will change in ADC processing modules, is shown, can be intuitively
See whether natural gas leaking situation and leak sensor work are abnormal；
Sound and light alarm, is connected with main control MCU, is whether the natural gas made to main control MCU leaks and respond, if natural gas
Leakage can then send sound and light alarm；
Externally communication, be connected with main control MCU, externally communication can with external bluetooth, wirelessly；
Button, for arranging natural gas leaking limit value, main control MCU can send instruction after limit value is reached.
2. it is a kind of according to claim 1 to use the method that dead band and biasing collection natural gas leaking state and concentration are set, its
It is characterised by, the leak sensor transmission signal is divided into：
Leak sensor,（By taking the conventional 5V power supply signals of tradition as an example）Leak sensor 1.5V is set used as reference offset electricity
Pressure, is also 0%LEL voltages, and 4.0V is used as 100%LEL output voltages；
When leak sensor exports V<VL(0.7V) or leak sensor V>VH(4.3V) when, it is believed that leak sensor self-inspection exception；
（VL For output voltage minimum of a value, VHFor output voltage maximum）
When leak sensor is exported in concentration of natural gas limit value<V<During 4.0V, main frame thinks the test point superleak, sends acousto-optic
Alarm signal.
3. it is a kind of according to claim 1 to use the method that dead band and biasing collection natural gas leaking state and concentration are set, its
It is characterised by, the main frame connects several leak sensors by transmission circuit.
4. it is a kind of according to claim 1 to use the method that dead band and biasing collection natural gas leaking state and concentration are set, its
It is characterised by, the detecting step is：
Gas sensor detects gas sensitive signal, and gas sensitive signal is transferred into processor of single chip computer；
ADC on processor of single chip computer is processed and for gas sensitive signal to be transformed into data signal, and data signal is transformed into through DAC process
Voltage signal, and be transported on main frame by transmission circuit；
Voltage signal is transformed into data signal by the ADC processing modules of main frame, is processed in digital data transmission to main control MCU and is divided
Analysis, when data signal exceed limit value when, sound and light alarm can be responded, when data signal is too low or or it is too high when, main control MCU meeting
Judge, assert leak sensor self-inspection exception, remind driver to be detected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710043344.4A CN106652365A (en) | 2017-01-21 | 2017-01-21 | Method for acquiring leak state and concentration of natural gas by setting dead zone and biasing |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201710043344.4A CN106652365A (en) | 2017-01-21 | 2017-01-21 | Method for acquiring leak state and concentration of natural gas by setting dead zone and biasing |
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| CN201710043344.4A Pending CN106652365A (en) | 2017-01-21 | 2017-01-21 | Method for acquiring leak state and concentration of natural gas by setting dead zone and biasing |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108227617A (en) * | 2018-02-13 | 2018-06-29 | 上海振华重工(集团)股份有限公司 | A kind of tyre crane remote detection and assessment system |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204641546U (en) * | 2015-06-03 | 2015-09-16 | 浙江万里学院 | Natural gas vehicle gas leakage monitoring system |
| CN105181752A (en) * | 2015-09-30 | 2015-12-23 | 浙江大学 | Multi-layer electrochemical gas sensing monitoring device |
| CN106128043A (en) * | 2016-08-10 | 2016-11-16 | 北京迪利科技有限公司 | Natural gas automobile fuel gas leakage compound sensor |
-
2017
- 2017-01-21 CN CN201710043344.4A patent/CN106652365A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204641546U (en) * | 2015-06-03 | 2015-09-16 | 浙江万里学院 | Natural gas vehicle gas leakage monitoring system |
| CN105181752A (en) * | 2015-09-30 | 2015-12-23 | 浙江大学 | Multi-layer electrochemical gas sensing monitoring device |
| CN106128043A (en) * | 2016-08-10 | 2016-11-16 | 北京迪利科技有限公司 | Natural gas automobile fuel gas leakage compound sensor |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108227617A (en) * | 2018-02-13 | 2018-06-29 | 上海振华重工(集团)股份有限公司 | A kind of tyre crane remote detection and assessment system |
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