CN220419227U - Gas concentration detecting system - Google Patents
Gas concentration detecting system Download PDFInfo
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- CN220419227U CN220419227U CN202320769407.5U CN202320769407U CN220419227U CN 220419227 U CN220419227 U CN 220419227U CN 202320769407 U CN202320769407 U CN 202320769407U CN 220419227 U CN220419227 U CN 220419227U
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- 238000005070 sampling Methods 0.000 claims abstract description 107
- 238000001514 detection method Methods 0.000 claims abstract description 104
- 238000007405 data analysis Methods 0.000 claims abstract description 9
- 239000004065 semiconductor Substances 0.000 claims description 18
- 230000005669 field effect Effects 0.000 claims description 4
- 229910044991 metal oxide Inorganic materials 0.000 claims description 4
- 150000004706 metal oxides Chemical class 0.000 claims description 4
- 238000005259 measurement Methods 0.000 description 9
- 230000007423 decrease Effects 0.000 description 6
- 238000004458 analytical method Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000004146 energy storage Methods 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 238000007084 catalytic combustion reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
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Abstract
The utility model provides a gas concentration detection system, comprising: the input end of the first sampling circuit is connected with the quantitative detection sensor and the temperature sensitive element, the output end of the first sampling circuit is grounded, and the first sampling circuit outputs a first sampling voltage; the input end of the second sampling circuit is electrically connected with the input ends of the quantitative detection sensor and the first sampling circuit, the output end of the second sampling circuit is grounded, and the second sampling circuit outputs a second sampling voltage; and the data analysis module is electrically connected with the first sampling circuit and the second sampling circuit and receives the first sampling voltage and the second sampling voltage. The utility model provides a gas detection circuit capable of maintaining high-precision detection of gas concentration when the environment changes drastically.
Description
Technical Field
The utility model relates to the technical field of image sensing, in particular to a gas concentration detection system.
Background
In places such as chemical plants, mines, laboratories and the like, target gas detection is a necessary safety protection and early warning measure. Particularly in the energy storage power station in the new energy field, timely and high-precision detection of gas production when the energy storage device fails is a key for safe operation of the energy storage power station.
In semiconductor gas sensors, variations in gas concentration and temperature can affect the resistive characteristics of the sensor. Semiconductor gas sensors have difficulty in achieving high-precision detection when temperature, gas concentration, and other factors cause dramatic changes in resistance. In addition, in order to realize high-precision detection of the gas concentration, a control system of the semiconductor gas sensor is too complex and the control cost is too high.
Disclosure of Invention
The utility model aims to provide a gas detection circuit which can maintain high-precision detection of gas concentration when the environment changes drastically.
In order to solve the technical problems, the utility model is realized by the following technical scheme:
as described above, the present utility model provides a gas concentration detection system including:
the input end of the first sampling circuit is connected with the quantitative detection sensor and the temperature sensitive element, the output end of the first sampling circuit is grounded, and the first sampling circuit outputs a first sampling voltage;
the input end of the second sampling circuit is electrically connected with the quantitative detection sensor and the input end of the first sampling circuit, the output end of the second sampling circuit is grounded, and the second sampling circuit outputs a second sampling voltage; and
the data analysis module is electrically connected to the first sampling circuit and the second sampling circuit, and receives the first sampling voltage and the second sampling voltage.
In an embodiment of the utility model, the second sampling circuit includes a switching element, and the switching element is an N-type metal oxide semiconductor field effect transistor or an N-type insulated gate bipolar transistor.
In an embodiment of the utility model, a gate of the switching element is electrically connected to the input end of the first sampling circuit and a drain or a collector of the switching element.
In an embodiment of the utility model, the first sampling circuit includes a first voltage dividing resistor, one end of the first voltage dividing resistor is electrically connected to the gate, and the other end of the first voltage dividing resistor is grounded.
In an embodiment of the utility model, the drain is electrically connected to an output end of the quantitative detection sensor, and a source of the switch element is grounded.
In an embodiment of the present utility model, when the quantitative detection sensor is in operation, the driving voltage of the gate is greater than the threshold voltage of the gate.
In an embodiment of the present utility model, when the quantitative detection sensor works, a conduction voltage drop of the switch element is greater than or equal to a difference value between the driving voltage and the threshold voltage.
In an embodiment of the utility model, the gas concentration detection system includes a second voltage divider, one end of the second voltage divider is electrically connected to the temperature sensitive element, and the other end of the second voltage divider is electrically connected to the input end of the first sampling circuit.
In an embodiment of the utility model, the gas concentration detection system includes a third voltage dividing resistor, one end of the third voltage dividing resistor is electrically connected to the quantitative detection sensor, and the other end of the third voltage dividing resistor is connected to the input end of the first sampling circuit.
In an embodiment of the utility model, the quantitative detection sensor is a semiconductor type gas sensor.
As described above, the present utility model provides a gas concentration detection system that samples a plurality of voltage data, is capable of sampling an ambient temperature, and is capable of concentration determination of a target gas concentration. In addition, according to the gas concentration detection system provided by the utility model, when the ambient temperature and the target gas concentration change to a large extent, for example, the gas concentration detection system provided by the utility model is used for measuring the sampling voltage of the ambient temperature and the gas concentration, the sampling voltage still can be stabilized in the rated range, and thus, the high-precision detection of the target gas concentration under any ambient condition is realized.
Of course, it is not necessary for any one product to practice the utility model to achieve all of the advantages set forth above at the same time.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are needed for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a gas concentration detection system according to an embodiment of the utility model.
Fig. 2 is a schematic circuit diagram of a data sampling module according to an embodiment of the utility model.
FIG. 3 is a graph showing the relationship between the concentration of a semiconductor resistor and the temperature of a gas in accordance with one embodiment of the present utility model.
Fig. 4 is a graph showing an output characteristic of the switching element Q1 according to an embodiment of the present utility model.
Fig. 5 is a graph showing an output characteristic of the switching element Q1 according to another embodiment of the present utility model.
Fig. 6 is a schematic structural diagram of a data analysis module according to an embodiment of the utility model.
In the figure: 10. a gas concentration detection system; 11. a data sampling module; 111. a first sampling circuit; 112. a second sampling circuit; 113. a quantitative detection sensor; 114. a temperature sensitive element; 12. a data analysis module; vcc, power supply end; GND, the ground terminal; r1, a first voltage dividing resistor; r2, a second voltage dividing resistor; r3, a third voltage dividing resistor; v1, a first sampling voltage; v2, second sampling voltage.
Detailed Description
The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.
In gas concentration detection, a gas sensor includes a sensing element, and a measurement circuit. The gas sensor converts the perceived gas to be measured into a measurable signal through the sensitive element and the sensing element, and quantitatively measures the gas to be measured through the measuring circuit. Gas sensors can be classified into catalytic combustion type, optical type, thermal conductivity change type, electrochemical type, and semiconductor resistance type. The semiconductor resistance type gas sensor uses a semiconductor material as a gas sensitive material, and can be adsorbed with gas to be detected in a preset temperature range, so that the conductivity of the gas sensitive material is changed, and further quantitative detection of the gas concentration is realized. The utility model provides a gas detection system, which is based on a semiconductor gas sensor and can realize high-precision detection of gas.
Referring to fig. 1 and 2, the gas concentration detection system provided by the present utility model includes a data sampling module 11 and a data analysis module 12. The data acquisition module 11 includes a first sampling circuit 111 and a second sampling circuit 112, and obtains first sampled data through the first sampling circuit 111 and second sampled data through the second sampling circuit 112. In the present embodiment, the first sampling data and the second sampling data are voltage data and temperature data. The data analysis module 12 obtains a target gas concentration from the first sample data and the second sample data. In this embodiment, the data acquisition module 11 further includes a quantitative detection sensor 113 and a temperature sensitive element 114. The input end of the first sampling circuit is connected to the quantitative detection sensor 113 and the temperature sensitive element 114, respectively, and the output end of the first sampling circuit 111 is grounded. The input end and the driving end of the second sampling circuit 112 are electrically connected to the input ends of the quantitative detection sensor 113 and the first sampling circuit 111, and the output end of the second sampling circuit 112 is grounded. In the present embodiment, the first sampling circuit outputs a first sampling voltage V1, and the second sampling circuit outputs a second sampling voltage V2. Wherein the quantitative detection sensor 113 and the temperature sensitive element 114 are connected in parallel between the power supply terminal Vcc and the ground terminal GND. In the present embodiment, the quantitative detection sensor 113 is a semiconductor type gas sensor, and the quantitative detection sensor 113 is a resistance type sensor. When the target gas concentration changes, the conductivity of the semiconductor gas sensitive material of the quantitative detection sensor 113 changes, thereby changing the first sampling voltage V1 and the second sampling voltage V2. When the temperature changes and the gas concentration suddenly changes, the resistance of the quantitative detection sensor 113 changes exponentially, and the detection system according to the utility model can avoid the sudden changes of V1 and V2, thereby improving the detection precision of the gas concentration.
Referring to fig. 1 to 3, in an embodiment of the present utility model, when the concentration of the gas to be measured in the detection environment changes, the conductivity of the semiconductor gas sensor element in the quantitative detection sensor 113 changes due to the adsorption of the gas to be measured. Therefore, the quantitative detection of the concentration of the gas to be detected in the air can be realized according to the change of the conductivity of the semiconductor gas sensor. Wherein the quantitative detection sensor 113 has a measurement range, for example, tests a carbon monoxide gas concentration of 50ppm to 500 ppm. The range of voltages that the quantitative detection sensor 113 can affect is limited corresponding to the gas concentration range. The first sampling circuit 111 and the second sampling circuit, the quantitative detection sensor 113 and the temperature sensitive element 114 provided by the utility model can stabilize the voltage of the gas detection system 10 in a high-precision test range and reduce temperature interference.
Referring to fig. 1 and 2, in an embodiment of the utility model, the first sampling circuit 111 includes a first voltage dividing element. In this embodiment, the first voltage dividing element may be a constant resistor, such as the first voltage dividing resistor R1 shown in fig. 2. As shown in fig. 2, the input end of the first voltage dividing resistor R1 is electrically connected to the quantitative detection sensor 113 and the temperature sensitive element 114. The output end of the first voltage dividing resistor R1 is grounded, and specifically, the output end of the first voltage dividing resistor R1 is connected to the ground end GND. In the present embodiment, the first voltage dividing resistor R1 is connected in series with the temperature sensitive element 114 and the quantitative detection sensor 113, respectively. When the resistance of the quantitative detection sensor 113 changes, the partial pressure of the quantitative detection sensor 113 changes, and thus the partial pressure of the first partial pressure resistor R1 in the first sampling circuit 111 also changes. The determination of the resistance change of the quantitative determination sensor 113 can be assisted by the voltage division of the first voltage dividing resistor R1, that is, the first sampling voltage V1, and the determination of the target gas concentration can be correspondingly performed by the resistance change of the quantitative determination sensor 113.
Referring to fig. 1 and 2, in an embodiment of the utility model, a second voltage dividing element is connected between the temperature sensing element 114 and the first voltage dividing resistor R1. In this embodiment, the second voltage dividing element may be a constant value resistor, such as the second voltage dividing resistor R2 shown in fig. 2. A third voltage dividing element is connected between the quantitative detection sensor 113 and the first voltage dividing resistor R1. In this embodiment, the third voltage dividing element may be a constant value resistor, such as the third voltage dividing resistor R3 shown in fig. 2. The second voltage dividing resistor R2 is connected in series with the temperature sensitive element 114, the quantitative detection sensor 113 is connected in series with the third voltage dividing resistor R3, and the second voltage dividing resistor R2 is connected in parallel with the third voltage dividing resistor R3. Specifically, the input ends of the second voltage dividing resistor R2 and the third voltage dividing resistor R3 are respectively connected to the temperature sensitive element 114 and the quantitative detection sensor 113, and the output ends of the second voltage dividing resistor R2 and the third voltage dividing resistor R3 are electrically connected to the first voltage dividing resistor R1. In the present embodiment, the resistance values of the temperature sensitive element 114 and the quantitative detection sensor 113 change synchronously with temperature. Also, the temperature sensitive element 114 is a negative temperature coefficient resistor insensitive to humidity. When the ambient temperature increases, the resistance of the temperature sensitive element 114 decreases, and the second voltage dividing element can prevent the quantitative detection sensor 113 from being shorted. Similarly, when the resistance of the quantitative detection sensor 113 is reduced, the third voltage dividing element can also help to adjust the current in the circuit, so as to avoid the line from being burnt by high current. In the present embodiment, as shown in fig. 2, the current passing through the temperature sensitive element 114 and the second voltage dividing element is I NTC The current through the first voltage dividing element is I1. The current through the quantitative detection sensor 113 is I SENSOR The current through the third voltage dividing resistor R3 is I2. Wherein I1 is I SENSOR And I2.
Referring to fig. 1 and 2, in an embodiment of the utility model, the second sampling circuit 112 includes a switching element Q1. The switching element Q1 and the quantitative detection sensor 113 are connected in series between the power supply terminal Vcc and the ground terminal GND. In this embodiment, the switching element Q1 may be an N-type metal oxide semiconductor field effect transistor (Metal Oxide Semiconductor Field Effect Transistor, MOSFET) or an N-type insulated gate bipolar transistor (Insulated Gate Bipolar Transistor, IGBT). Taking MOSFET as an example, the switching element Q1 includes a gate G, a source S, and a drain D. The source S is electrically connected to the ground GND, the drain D is electrically connected to the quantitative detection sensor 113, and the gate G is electrically connected to the first sampling circuit 111. Specifically, the gate G is electrically connected to the input end of the first voltage dividing element, the output end of the second voltage dividing element, and the output end of the third voltage dividing element. The drain D is electrically connected to the output end of the quantitative detection sensor 113 and the input end of the third voltage dividing element. The source S is grounded. In the present embodiment, the voltage division of the switching element Q1 is the second sampling voltage V2. The current through the switching element Q1 is I Q . Wherein the divided voltage of the second sampling voltage V2 and the quantitative detection sensor 113 is the power supply voltage Vcc. Therefore, the target gas concentration can be determined by directly determining the partial pressure of the quantitative detection sensor 113 by acquiring V2. Wherein the total voltage after the first voltage dividing element and the third voltage dividing element are connected in series is also V2. When V2 changes, the currents I1 and I2 through the first and third voltage dividing elements also change.
Referring to fig. 1 to 3, in an embodiment of the utility model, when the ambient temperature or the target gas concentration is changed drastically, and other environmental parameters are unchanged, for example, the ambient temperature or the target gas concentration is increased drastically, the resistance of the quantitative detection sensor 113 is decreased rapidly. For example, Q1 is in the off state regardless of the switching element Q1. Since V2 increases, and the resistances of the first voltage dividing element R1 and the third voltage dividing resistor R3 are unchanged, I2 rises. The surge current in the detection circuit causes the first sampled voltage to rapidly approach the voltage Vcc of the power supply terminal Vcc. As shown in fig. 3, in the case where an exponential data change occurs, the test accuracy of the gas concentration detection system is difficult to ensure. The gas concentration detection system 10 provided according to the present utility model is capable of effectively changing such an exponential variation trend.
Referring to fig. 1, 4 and 5, in an embodiment of the utility model, the switching element Q1 may be an N-type MOSFET or an N-type IGBT. Fig. 4 is an output characteristic curve of an N-type MOSFET, and fig. 5 is an output characteristic curve of an N-type IGBT. As shown in fig. 4 and 5, a region a is a forward blocking region, a region b is a constant current region, and a region c is a switching region of the switching element Q1. In fig. 4 and 5, ic and Id are on-currents of the switching element Q1, vgs and Vge are driving voltages of the gate G, and Vds and Vce are on-voltage drops of the switching element Q1. With respect to the switching element Q1, the threshold voltages of the gate G represent Vgs (th) and Vge (th). In the region a, the threshold voltage of the gate G is greater than the driving voltage of the gate G, that is, vgs (th) > Vgs, vge (th) > Vge, the switching element Q1 is not turned on. In the region b, the driving voltage of the gate G is greater than the threshold voltage of the gate G, that is, vgs > Vgs (th), vge > Vge (th). And the conduction voltage drop of the switch piece Q1 is larger than or equal to the difference value between the gate driving voltage and the gate threshold voltage, namely Vds is larger than or equal to Vgs-Vgs (th), and Vce is larger than or equal to Vge-Vge (th). When the voltage of the gate G is constant, the on-current of the switch Q1 is independent of the on-voltage drop. Therefore, when the temperature and the gate voltage are constant, the on current of the switching element Q1 is only related to the gate voltage. And the larger the gate voltage of the switching element Q1, the larger the on-current. In the region c, the driving voltage of the gate G is greater than the threshold voltage of the gate G, that is, vgs > Vgs (th), vge > Vge (th). And, the on-voltage drop of the switching element Q1 is smaller than the difference between the gate driving voltage and the gate threshold voltage, i.e., vds < Vgs-Vgs (th), vce < Vge-Vge (th). In region c, the on-currents (Ids and Ice) are linear with the on-voltage drops (Vds, vde), and the loss of the switching element Q1 is low. In this embodiment, when the gas concentration detection system 10 is operated, specifically, the operating area of the switching element Q1 is a constant current area corresponding to the area b. Therefore, according to the gas concentration detection system 10 provided by the utility model, the on-current of the device can be deduced according to the characteristic curve of the device body under the conditions that the ambient temperature can be known and the gate driving voltage can be accurately sampled. And, by controlling the magnitude of the gate driving voltage, the amplitude adjustment of the constant current can be realized.
Referring to fig. 1 to 3, and fig. 6, in an embodiment of the utility model, the data analysis module 12 includes a measurement unit 121 and an analysis unit 122. The measurement unit 121 is electrically connected to the first sampling circuit 111 and the second sampling circuit 112. In the present embodiment, the measurement unit 121 is a voltage measurement device, such as a voltmeter. The measurement unit 121 may measure and output a first sampling voltage V1 and a second sampling voltage V2. Specifically, the measurement ends of the measurement unit 121 are connected to two ends of the first voltage dividing element, so as to measure the voltage division V1 of the first voltage dividing element R1. And, the measuring terminal of the other measuring unit 121 is connected to the drain D and the source S of the switching element Q1, so as to measure the second sampling voltage V2. In the present embodiment, the analysis unit 122 may receive the first sampling voltage V1 and the second sampling voltage V2, and calculate the resistance R of the quantitative detection sensor 113 according to V1 and V2 SENSOR And ambient temperature T a . In the present embodiment, the analysis unit 122 may be a computer, or may be an arithmetic unit in a computer.
Referring to fig. 1 to 3, and fig. 6, in an embodiment of the present utility model, the analysis principle related to the present utility model is described below. When the driving voltage of the gate G is greater than the threshold voltage of the gate G, and the on-voltage drop of the switch Q1 is greater than or equal to the difference between the gate driving voltage and the gate threshold voltage, the resistance of the temperature sensing element 114 is related to the first sampling voltage V1, the second sampling voltage V2, the first voltage dividing element R1, the second voltage dividing resistor R2, the third voltage dividing resistor R3 and the voltage Vcc of the power supply terminal. And specifically, the resistance R of the temperature sensitive element 114 NTC Can be represented by formula (1).
Referring to fig. 1 to 3, 6 and (1), in one embodiment of the present utility model, the ambient temperature T can be obtained according to the resistance of the temperature sensitive element 114 a . Wherein the ambient temperature T a Equation (2) can be expressed.
Referring to fig. 1 to 3 and 6, and formulae (1) and (2), in one embodiment of the present utility model, the temperature T is set according to the rated temperature N Resistance R of temperature sensitive element 114 NTC The temperature coefficient B of the temperature sensitive element 114 and the temperature is the rated temperature T N The resistance RN of the thermistor NTC can acquire the value of the ambient temperature. Wherein T is N 、R N And B is a determinable parameter. Therefore, according to the gas concentration detection system provided by the utility model, the value of the ambient temperature can be obtained, and the temperature sampling is realized. In the present embodiment, the data analysis module 12 obtains the first sampling voltage V1 and the second sampling voltage V2, and according to the formula (1) and the formula (2), data sampling of the ambient temperature can be achieved.
Referring to fig. 1 to 3, 6, and formulas (1) and (2), in an embodiment of the utility model, the quantitative detection sensor 113 is a resistive sensor, and different resistance values of the quantitative detection sensor 113 correspond to different target gas concentrations. Specifically, the target gas concentration and the resistance value of the quantitative detection sensor 113 and the ambient temperature T a And (5) correlation. In the present embodiment, the ambient temperature T is obtained according to the formula (1) and the formula (2) a Then, the first sampling voltage V1 and the ambient temperature T are combined a The on-current of the switching element Q1 can be calculated. The current I of the quantitative detection sensor 113 can be obtained by combining the equivalent on-resistance of the switching element Q1 SENSOR . At the known switching element Q1, the voltage division is performed, i.e., the second sampling voltage V2, the voltage division of the quantitative detection sensor 113 is thus the difference between the power supply voltage Vcc and the second sampling voltage V2. While at current I SENSOR Based on the known value and the known partial pressure, the resistance R of the quantitative detection sensor 113 is determined SENSOR Is also available. According to the resistance R of the quantitative detection sensor 113 SENSOR The concentration of the target gas can be confirmed. In the present embodiment, the resistance value R of the quantitative determination sensor 113 SENSOR Can be represented by formula (3).
Referring to fig. 1 to 3, 6, and equations (1), (2) and (3), in an embodiment of the utility model, when the ambient temperature or the target gas concentration changes drastically, for example, the resistance of the quantitative detection sensor 113 suddenly drops, the partial pressure V2 of the switch Q1 tends to increase. While V2 increases, the voltage division of the third voltage dividing resistor R3 increases, and thus I2 increases. As I2 increases, the first sampling voltage V1 tends to increase. Therefore, the switching element Q1 is in the constant current region, and the driving voltage of the gate G increases, so that the on current I of the switching element Q1 Q Will also surge, and I Q Is much higher than I2. Current I through quantitative detection sensor 113 SENSOR Is divided into I2 and I Q . And I Q Is much higher than I2, and therefore the equivalent on-resistance of the switching element Q1 decreases. Wherein the equivalent on-resistance of the switching element Q1 can be V2 and I of the on-current of the switching element Q1 Q Is a ratio of (2). The increasing trend of V2 is thus suppressed. According to the gas concentration detection system 10 provided by the present utility model, the second sampling voltage V2 can be maintained within a suitable interval. Wherein, the suitable interval of V2 may be the data interval verified in the device test phase. Therefore, the first sampling voltage V1 can be maintained in a proper interval under the condition that the power supply voltage Vcc is unchanged, so as to stabilize the gate voltage of the switch Q1 and the I Q . When the environmental factor causes a sudden increase in the resistance value of the quantitative determination sensor 113, V2 tends to decrease, so I2 decreases, I1 decreases, and V1 tends to decrease. The driving voltage of the gate G is reduced when the switching element Q1 is in the constant current region, and the on current I of the switching element Q1 is reduced Q The equivalent on-resistance of the switch Q1 rapidly rises, so that the falling trend of the V2 tube is restrained, and the first sampling voltage V1 and the second sampling voltage V2 are in a proper sampling interval.
The embodiments of the utility model disclosed above are intended only to help illustrate the utility model. The examples are not intended to be exhaustive or to limit the utility model to the precise forms disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the utility model and the practical application, to thereby enable others skilled in the art to best understand and utilize the utility model. The utility model is limited only by the claims and the full scope and equivalents thereof.
Claims (10)
1. A gas concentration detection system, comprising:
the input end of the first sampling circuit is connected with the quantitative detection sensor and the temperature sensitive element, the output end of the first sampling circuit is grounded, and the first sampling circuit outputs a first sampling voltage;
the input end of the second sampling circuit is electrically connected with the quantitative detection sensor and the input end of the first sampling circuit, the output end of the second sampling circuit is grounded, and the second sampling circuit outputs a second sampling voltage; and
the data analysis module is electrically connected to the first sampling circuit and the second sampling circuit, and receives the first sampling voltage and the second sampling voltage.
2. The gas concentration detection system of claim 1, wherein the second sampling circuit comprises a switching element, and the switching element is an N-type metal oxide semiconductor field effect transistor or an N-type insulated gate bipolar transistor.
3. The gas concentration detection system of claim 2, wherein the gate of the switching element is electrically connected to the input of the first sampling circuit and the drain or collector of the switching element.
4. A gas concentration detection system according to claim 3, wherein the first sampling circuit comprises a first voltage dividing resistor, one end of the first voltage dividing resistor is electrically connected to the gate, and the other end of the first voltage dividing resistor is grounded.
5. A gas concentration detection system according to claim 3, wherein the drain is electrically connected to the output of the quantitative detection sensor, and the source of the switch is grounded.
6. A gas concentration detection system according to claim 3, wherein the drive voltage of said gate electrode is greater than the threshold voltage of said gate electrode when said quantitative detection sensor is in operation.
7. The gas concentration detection system according to claim 6, wherein a conduction voltage drop of the switching element is equal to or larger than a difference between the driving voltage and the threshold voltage when the quantitative detection sensor is operated.
8. The gas concentration detection system of claim 1, wherein the gas concentration detection system comprises a second voltage divider, one end of the second voltage divider is electrically connected to the temperature sensitive element, and the other end of the second voltage divider is electrically connected to the input end of the first sampling circuit.
9. The gas concentration detection system according to claim 1, wherein the gas concentration detection system comprises a third voltage dividing resistor, one end of the third voltage dividing resistor is electrically connected to the quantitative detection sensor, and the other end of the third voltage dividing resistor is connected to the input end of the first sampling circuit.
10. The gas concentration detection system according to claim 1, wherein the quantitative detection sensor is a semiconductor type gas sensor.
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| CN202320769407.5U CN220419227U (en) | 2023-04-04 | 2023-04-04 | Gas concentration detecting system |
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| CN202320769407.5U CN220419227U (en) | 2023-04-04 | 2023-04-04 | Gas concentration detecting system |
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