CN205229027U - Infra -red transmitter's temperature compensating device and infrared detection device for two -phase flow detects - Google Patents
Infra -red transmitter's temperature compensating device and infrared detection device for two -phase flow detects Download PDFInfo
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- CN205229027U CN205229027U CN201520857239.0U CN201520857239U CN205229027U CN 205229027 U CN205229027 U CN 205229027U CN 201520857239 U CN201520857239 U CN 201520857239U CN 205229027 U CN205229027 U CN 205229027U
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Abstract
The utility model discloses an infra -red transmitter's that two -phase flow detected temperature compensated equipment, including temperature measuring unit and temperature compensating unit, the input of temperature compensating unit links to each other with temperature measuring unit and is used for generating the voltage signal who changes along with temperature measuring unit's temperature signal, and the output of temperature compensating unit links to each other with infra -red transmitter's drive circuit's input, is used for to remain unchanged with the output luminous power of maintaining infra -red transmitter according to voltage signal adjustment drive circuit's temperature compensating 2. The utility model also discloses an infrared detection device, including infra -red transmitter, infrared receiver, drive circuit and temperature compensated equipment, temperature compensated equipment link to each other with drive circuit the drive current that is used for adjusting drive circuit so that infra -red transmitter's output luminous power remain unchanged. The utility model discloses a temperature compensated equipment and infrared detection device all have simple structure, can compensate ambient temperature to advantages such as infra -red transmitter output luminous power influence and measuring precision height.
Description
Technical field
The utility model relates generally to technical field of optical detection, refers in particular to a kind of temperature compensation means and infrared detecting device of the infrared transmitter for biphase gas and liquid flow detection.
Background technology
At present, for the equipment such as manned space station, submarine, it is all generally the oxygen supply demand that employing brine electrolysis method for producing oxygen through realizes to occupant.SPE (solidpilymerelectrode) electrolysis oxygenerating technology is electrolytical brine electrolysis oxygenerating technology with solid polymer.Electrolysis oxygenerating technology is widely used on the equipment such as spacecraft, nuclear submarine at present, replaces traditional alkaline electrolysis oxygenerator.In SPE electrolysis oxygenerator, the water as reactant passes through purification, circulates between electrolytic tank, heat interchanger, water tank.Gas/water mixture that reaction produces is separated by moisture separator, and isolated water will drop into circulation again.In the process, the water of non-electrolysis needs to recycle, and the water returned is usually with a certain amount of hydrogen and oxygen, for gas-liquid two-phase fluid-mixing, if the Air Bubble Size in biphase gas and liquid flow and volume content exceed certain proportion, easily cause " cavitation erosion " phenomenon, cause the damage of electrolysis oxygenerator ebullator, this all will cause great potential safety hazard to electrolysis oxygenerator and even whole equipment, therefore need to detect the Air Bubble Size in water and volume content in real time, judge whether electrolysis oxygenerator normally works, and prevents the generation of security incident.
The method of domestic and international biphase gas and liquid flow Measurement and analysis mainly contains ultrasonic Method for Measuring, electromagnetic method, capacitance measurement and optical detection, and what wherein optical detection utilized is that the infrared light of water to specific band has absorption, and gas is without the principle of absorption.Its theoretical foundation is Beer-Lambert (Beer-Lambert) law, and at a particular wavelength, on the energy of infrared transmission and optical path, the molecular amounts of absorption near infrared ray is inversely proportional to.Infrared radiation is shown in formula (1) by relation between the concentration C of the light intensity I after test pipeline and the ratio of incident intensity I0 and absorbing material water, optical path length d and extinction coefficient K:
I/I0=exp(-Kcd)(1)
In formula (1): I-is by the infrared light intensity after pipeline; The infrared incident intensity of I0-; K-extinction coefficient; C-aqueous water concentration; D-measuring channel length.
The hardware adopted in optical detection generally comprises an infra-red laser diode and driving circuit, infrared receiving tube and testing circuit thereof, temperature-adjusting circuit three parts.Driving circuit drives infra-red laser diode to produce infrared light, after biphase gas and liquid flow absorbs, is received and produces photocurrent, realize detecting by infrared receiving tube; When the liquid water content in biphase gas and liquid flow changes, the absorbed situation of infrared light also changes, thus the photocurrent that receiving tube is exported also changes, and after testing after processing of circuit, shows as output voltage change, represents different gas-liquid two-phase content.Because infra-red laser diode device is extremely responsive to environment temperature, when environment temperature raises, under identical drive current, its output intensity diminishes, and affects accuracy of detection greatly; Therefore usually toward contact, complicated temperature-adjusting circuit and structure to be set, under ensureing that infra-red laser diode works in stationary temperature, to ensure accuracy of detection.But adopt the integrated infra-red laser diode of mode infrared emission core body of TEC (semiconductor cooler) temperature control, semiconductor chilling plate and temperature detecting resistance, complex structure, require high to core body integrated technique; And TEC temperature control must arrange complicated temperature-adjusting circuit, and power consumption is large, TEC and temperature-adjusting circuit poor reliability.
Utility model content
The technical problems to be solved in the utility model is just: the technical matters existed for prior art, the utility model provide a kind of structure simple, the change that Yin Wendu affects the infrared transmitter Output optical power caused can be compensated, thus the temperature compensation means of the infrared transmitter for biphase gas and liquid flow detection keeping infrared transmitter Output optical power constant, and the corresponding infrared detecting device detected for biphase gas and liquid flow providing a kind of accuracy of detection not affect by variation of ambient temperature.
For solving the problems of the technologies described above, the technical scheme that the utility model proposes is:
A kind of temperature compensation means of the infrared transmitter for biphase gas and liquid flow detection, comprise temperature compensation unit and the temperature measuring unit for measuring infrared transmitter internal temperature, the input end of described temperature compensation unit is connected with described temperature measuring unit and changes and the voltage signal changed for the temperature signal generated with described temperature measuring unit, and the output terminal of described temperature compensation unit is connected with the input end of the driving circuit of described infrared transmitter, remain unchanged with the Output optical power maintaining infrared transmitter for the drive current adjusting driving circuit according to voltage signal.
Further improvement as technique scheme:
Described temperature measuring unit is the temperature detecting resistance being installed on described infrared transmitter inside.
Described temperature compensation unit comprises the first resistance unit, the second resistance unit and the 3rd resistance unit of connecting successively, one end of described first resistance unit is connected with power supply+5V, the other end is connected with one end of described second resistance unit, one end of described 3rd resistance unit is connected with earth terminal, the other end is connected with the other end of described second resistance unit, and described 3rd resistance unit is in parallel with described temperature detecting resistance; One end that described first resistance unit connects the second resistance unit is connected with the input end of described driving circuit.
Also comprise operational amplifier U1A, the other end of described first resistance unit is connected with the inverting input of described operational amplifier UA1 by resistance R3, the inverting input of described operational amplifier U1A is connected with output terminal by a resistance R1, and the in-phase input end of described operational amplifier U1A is connected with power supply+2.5V; The output terminal of described operational amplifier UA1 is connected with the input end of described driving circuit.
Described temperature detecting resistance is thermistor.
Described first resistance unit, the second resistance unit and the 3rd resistance unit form by multiple resistant series.
The invention also discloses a kind of infrared detecting device detected for biphase gas and liquid flow, comprise infrared transmitter, infrared remote receiver, for driving the driving circuit of infrared transmitter, also comprise temperature compensation means as above, described temperature compensation means is connected with described driving circuit and remains unchanged with the Output optical power maintaining infrared transmitter for the drive current adjusting driving circuit.
Further improvement as technique scheme:
Described driving circuit comprises operational amplifier U1B and transistor Q1, the in-phase input end of described operational amplifier U1B is connected with the output terminal of described temperature compensation means, inverting input is connected with the negative pole of infrared transmitter and passes through resistance R1 and is connected with earth terminal, the output terminal of described operational amplifier U1B is connected with the base stage of transistor Q1, the collector of described transistor Q1 is connected with power supply VCC by resistance R2, and the described emitter of transistor Q1 is connected with the positive pole of infrared transmitter.
Described infrared transmitter is infra-red laser diode.
Compared with prior art, the utility model has the advantage of:
The temperature compensation means of the infrared transmitter for biphase gas and liquid flow detection of the present utility model, temperature compensation unit adjusts the input voltage of infrared transmitter driving circuit in real time according to the temperature signal of temperature measuring unit, thus the output current of adjustment driving circuit remains unchanged with the luminous power making infrared transmitter export, thus make biphase gas and liquid flow accuracy of detection not by the impact of variation of ambient temperature; And temperature compensation means structure of the present utility model simple, be easy to realize.Infrared detecting device for biphase gas and liquid flow detection of the present utility model is provided with temperature compensation means, can increase according to current environmental temperature or reduce the drive current of infra-red laser diode, compensate and raise or decline the Output optical power decline or rising that cause because of environment temperature, thus keep the Output optical power of infra-red laser diode constant, make biphase gas and liquid flow accuracy of detection not by the impact of variation of ambient temperature.
Accompanying drawing explanation
Fig. 1 is temperature compensation means frame assumption diagram in a particular embodiment in the utility model.
Fig. 2 is the circuit theory diagrams of temperature compensation means and driving circuit in the utility model.
Number in the figure illustrates: 1, temperature measuring unit; 2, temperature compensation unit; 3, driving circuit; 4, infrared transmitter.
Embodiment
Below in conjunction with Figure of description and specific embodiment, the utility model is further described.
As depicted in figs. 1 and 2, the temperature compensation means of the infrared transmitter for biphase gas and liquid flow detection of the present embodiment, comprise the temperature measuring unit 1 for measuring infrared transmitter 4 internal temperature and temperature compensation unit 2, temperature measuring unit 1 in the present embodiment, for being installed on the temperature detecting resistance of infrared transmitter 4 inside, is specially thermistor; The input end of temperature compensation unit 2 is connected with temperature measuring unit 1 and changes and the voltage signal changed for the temperature signal generated with temperature measuring unit 1, and the output terminal of temperature compensation unit 2 is connected with the input end of the driving circuit 3 of infrared transmitter 4, remain unchanged with the Output optical power maintaining infrared transmitter 4 for the drive current adjusting driving circuit 3 according to voltage signal.The temperature compensation means of the infrared transmitter for biphase gas and liquid flow detection of the present embodiment, be connected with temperature measuring unit 1 by temperature compensation unit 2, export temperature variant magnitude of voltage, as the output current setting value of driving circuit 3, its Changing Pattern is as follows: 1, when environment temperature raises, the resistance that thermistor in infrared transmitter 4 records reduces, after temperature compensated unit 2, output voltage rising and current setting value increase, driving circuit 3 drives the drive current of infrared transmitter 4 to increase, Output optical power is increased, compensate the Output optical power caused because environment temperature raises to decline, 2, when environment temperature reduces, thermistor resistance in infrared transmitter 4 increases, after temperature compensated unit 2, output voltage reduction and current setting value reduce, driving circuit 3 drives the drive current of infrared transmitter 4 to reduce, Output optical power is reduced, compensates the Output optical power caused because environment temperature reduces and increase.Therefore, temperature compensation means of the present utility model can increase according to current environmental temperature or reduce the drive current of infrared transmitter 4, compensate and raise or decline the Output optical power decline or rising that cause because of environment temperature, thus keep the Output optical power of infrared transmitter 4 constant, make biphase gas and liquid flow accuracy of detection not by the impact of variation of ambient temperature.In addition in the present embodiment, infrared transmitter 4 is infra-red laser diode.
As shown in Figure 2, in the present embodiment, temperature compensation unit 2 comprises the first resistance unit, the second resistance unit and the 3rd resistance unit of connecting successively, one end of first resistance unit is connected with power supply+5V, the other end is connected with one end of the second resistance unit, one end of 3rd resistance unit is connected with earth terminal, and the other end is connected with the other end of the second resistance unit, and the 3rd resistance unit is in parallel with temperature detecting resistance; One end that first resistance unit connects the second resistance unit is connected with the input end of driving circuit 3.
As shown in Figure 2, in the present embodiment, the other end of the first resistance unit is connected with the input end of driving circuit 3 by operational amplifier U1A, the other end of the first resistance unit is connected with the inverting input of operational amplifier UA1 by resistance R3, the inverting input of operational amplifier U1A is connected with output terminal by a resistance R1, and the in-phase input end of operational amplifier U1A is connected with power supply+2.5V; The output terminal of operational amplifier UA1 is connected with the input end of driving circuit 3.
In the present embodiment, first resistance unit, the second resistance unit and the 3rd resistance unit form by multiple resistant series, be specially the first resistance unit to be in series by resistance R11 ~ R13, the second resistance unit is in series by R14 ~ R16, and the 3rd resistance unit is in series by R17 ~ R19.Wherein resistance can adopt the resistor of plain metal film resistor, thermistor or other type.
Be described below the course of work of temperature compensation means of the present utility model by reference to the accompanying drawings: be 50 Ω with drive current 50mA, R1 under normal working temperature, operating temperature range 0 ~ 40 DEG C is example.
As normal working temperature be 20 DEG C time, infra-red laser diode drive current is 50mA; During low temperature 0 DEG C, infra-red laser diode luminescence efficiency promotes, and according to the output characteristic curve of infra-red laser diode, the drive current needed for light intensity when reaching working temperature 20 DEG C of drive current 50mA exports is reduced to 46.64mA; During high temperature 40 DEG C, infra-red laser diode luminescence efficiency reduces, and according to the output characteristic curve of infra-red laser diode, the drive current needed for light intensity when reaching working temperature 20 DEG C of drive current 50mA exports need be increased to 54.14mA.
Namely when normal working temperature is 20 DEG C, thermosensitive resistance RT
20=10k Ω, the drive current of infra-red laser diode is 50mA, then the in-phase input end of operational amplifier U1B should be made to be 2.5V, and the output voltage of temperature compensation unit 2 should be 2.5V;
During low temperature 0 DEG C, thermosensitive resistance is RT
0=25.16k Ω, the drive current of infra-red laser diode is 46.64mA, then the in-phase input end of operational amplifier U1B should be made to be 46.64mAx50 Ω=2.332V, and temperature compensation unit 2 voltage exports and should be 2.668V;
During high temperature 40 DEG C, thermosensitive resistance is RT
40=4.47k Ω, the drive current of infra-red laser diode is 54.14mA, then the in-phase input end of operational amplifier U1B should be made to be 54.14mAx50 Ω=2.707V, and the voltage of temperature compensation unit 2 exports and should be 2.293V.
Can list 20 DEG C according to resistance connection in series-parallel and dividing potential drop computing formula, the output formula under 0 DEG C and 40 DEG C of working conditions is
Solve that to obtain approximate solution as follows:
(R
11+R
12+R
13)=8.363kΩ(5)
(R
14+R
15+R
16)=4.450kΩ(6)
(R
17+R
18+R
19)=6.430kΩ(7)
In the present embodiment, R11, R12, R13 adopt 8.2k Ω, 160 Ω and 3 Ω, tri-plain metal film resistors to realize this resistance respectively; R14, R15, R16 adopt 4.3k Ω, 130 Ω and 20 Ω, tri-plain metal film resistors to realize this resistance respectively; R17, R18, R19 adopt 5.6k Ω, 820 Ω and 10 Ω, tri-plain metal film resistors to realize this resistance respectively.
The invention also discloses a kind of infrared detecting device detected for biphase gas and liquid flow, comprise infrared transmitter 4, infrared remote receiver, for driving the driving circuit 3 of infrared transmitter 4, also comprise temperature compensation means as above, temperature compensation means is connected with driving circuit 3 and remains unchanged with the Output optical power maintaining infrared transmitter 4 for the drive current adjusting driving circuit 3.Infrared detecting device for biphase gas and liquid flow detection of the present utility model is provided with temperature compensation means, can increase according to current environmental temperature or reduce the drive current of infra-red laser diode, compensate and raise or decline the Output optical power decline or rising that cause because of environment temperature, thus keep the Output optical power of infra-red laser diode constant, make biphase gas and liquid flow accuracy of detection not by the impact of variation of ambient temperature.
In the present embodiment, driving circuit 3 comprises operational amplifier U1B and transistor Q1, the in-phase input end of operational amplifier U1B is connected with the output terminal of temperature compensation means, inverting input is connected with the negative pole of infrared transmitter 4 and passes through resistance R1 and is connected with earth terminal, the output terminal of operational amplifier U1B is connected with the base stage of transistor Q1, the collector of transistor Q1 is connected with power supply VCC by resistance R2, and the emitter of transistor Q1 is connected with the positive pole of infrared transmitter 4.
Below be only preferred implementation of the present utility model, protection domain of the present utility model be not only confined to above-described embodiment, all technical schemes belonged under the utility model thinking all belong to protection domain of the present utility model.It should be pointed out that for those skilled in the art, not departing from the some improvements and modifications under the utility model principle prerequisite, protection domain of the present utility model should be considered as.
Claims (9)
1. the temperature compensation means of the infrared transmitter detected for biphase gas and liquid flow, it is characterized in that, comprise temperature compensation unit (2) and the temperature measuring unit (1) for measuring infrared transmitter (4) internal temperature, the input end of described temperature compensation unit (2) is connected with described temperature measuring unit (1) and changes and the voltage signal changed for the temperature signal generated with described temperature measuring unit (1), the output terminal of described temperature compensation unit (2) is connected with the input end of the driving circuit (3) of described infrared transmitter (4), for remaining unchanged with the Output optical power maintaining infrared transmitter (4) according to the drive current of voltage signal adjustment driving circuit (3).
2. the temperature compensation means of the infrared transmitter for biphase gas and liquid flow detection according to claim 1, is characterized in that, described temperature measuring unit (1) is for being installed on the inner temperature detecting resistance of described infrared transmitter (4).
3. the temperature compensation means of the infrared transmitter for biphase gas and liquid flow detection according to claim 2, it is characterized in that, described temperature compensation unit (2) comprises the first resistance unit, the second resistance unit and the 3rd resistance unit of connecting successively, one end of described first resistance unit is connected with power supply+5V, the other end is connected with one end of described second resistance unit, one end of described 3rd resistance unit is connected with earth terminal, the other end is connected with the other end of described second resistance unit, and described 3rd resistance unit is in parallel with described temperature detecting resistance; One end that described first resistance unit connects the second resistance unit is connected with the input end of described driving circuit (3).
4. the temperature compensation means of the infrared transmitter for biphase gas and liquid flow detection according to claim 3, it is characterized in that, also comprise operational amplifier U1A, the other end of described first resistance unit is connected with the inverting input of described operational amplifier UA1 by resistance R3, the inverting input of described operational amplifier U1A is connected with output terminal by a resistance R1, and the in-phase input end of described operational amplifier U1A is connected with power supply+2.5V; The output terminal of described operational amplifier UA1 is connected with the input end of described driving circuit (3).
5. the temperature compensation means of the infrared transmitter for biphase gas and liquid flow detection according to Claims 2 or 3 or 4, it is characterized in that, described temperature detecting resistance is thermistor.
6. the temperature compensation means of the infrared transmitter for biphase gas and liquid flow detection according to claim 3 or 4, it is characterized in that, described first resistance unit, the second resistance unit and the 3rd resistance unit form by multiple resistant series.
7. the infrared detecting device detected for biphase gas and liquid flow, comprise infrared transmitter (4), infrared remote receiver, for driving the driving circuit (3) of infrared transmitter (4), it is characterized in that, also comprise as the temperature compensation means in claim 1 to 6 as described in any one, described temperature compensation means is connected with described driving circuit (3) and remains unchanged with the Output optical power maintaining infrared transmitter (4) for the drive current adjusting driving circuit (3).
8. the infrared detecting device for air-flow two-phase flow according to claim 7, it is characterized in that, described driving circuit (3) comprises operational amplifier U1B and transistor Q1, the in-phase input end of described operational amplifier U1B is connected with the output terminal of described temperature compensation means, inverting input is connected with the negative pole of infrared transmitter (4) and passes through resistance R1 and is connected with earth terminal, the output terminal of described operational amplifier U1B is connected with the base stage of transistor Q1, the collector of described transistor Q1 is connected with power supply VCC by resistance R2, the emitter of described transistor Q1 is connected with the positive pole of infrared transmitter (4).
9. the infrared detecting device for air-flow two-phase flow according to claim 7 or 8, is characterized in that, described infrared transmitter (4) is infra-red laser diode.
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN105319160A (en) * | 2015-10-30 | 2016-02-10 | 中国电子科技集团公司第四十八研究所 | Temperature compensation device for infrared transmitter for gas-liquid two-phase flow detection and infrared detection device |
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2015
- 2015-10-30 CN CN201520857239.0U patent/CN205229027U/en not_active Withdrawn - After Issue
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
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CN105319160A (en) * | 2015-10-30 | 2016-02-10 | 中国电子科技集团公司第四十八研究所 | Temperature compensation device for infrared transmitter for gas-liquid two-phase flow detection and infrared detection device |
CN105319160B (en) * | 2015-10-30 | 2020-06-26 | 中国电子科技集团公司第四十八研究所 | Temperature compensation device of infrared emitter for gas-liquid two-phase flow detection and infrared detection device |
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