CN-121994666-A - Particulate matter concentration detection device and method for double-angle sensor

CN121994666ACN 121994666 ACN121994666 ACN 121994666ACN-121994666-A

Abstract

The invention relates to the technical field of concentration detection and discloses a particulate matter concentration detection device and method of a dual-angle sensor, wherein the device comprises a light beam output module, a detection shell, a first optical sensor, a second optical sensor, a first amplification sampling circuit, a second amplification sampling circuit and a control module, wherein an included angle between a connecting line of a midpoint of the first optical sensor and a detecting light beam and the detecting light beam is equal to a first preset angle, an included angle between a connecting line of the midpoint of the second optical sensor and the detecting light beam is equal to a second preset angle, the control module obtains a sampling value of a first scattered light energy signal and a sampling value of a second scattered light energy signal, the first particulate matter concentration and the second particulate matter concentration are respectively calculated according to the sampling values, the first particulate matter concentration and a preset threshold value are compared, if the first particulate matter concentration is larger than the preset threshold value, the first particulate matter concentration is output, and otherwise, the second particulate matter concentration is output. The invention realizes the accurate detection of the full concentration range.

Inventors

LI DAN
LIU LIXUN
ZHANG ZHENGWEI
Zhao Luoqi
Qiu xing
WANG JIANPING

Assignees

中电科东方通信集团有限公司

Dates

Publication Date: 20260508
Application Date: 20260303

Claims (10)

1. A particulate matter concentration detection apparatus of a dual angle sensor, comprising: the light beam output module is used for outputting detection light beams; The detection shell is hollow to form a detection cavity, a detection inlet is formed in the detection shell, and the detection light beam enters the detection cavity through the detection inlet; the first optical sensor is arranged on the detection shell, and an included angle between a connecting line of the first optical sensor and the midpoint of the detection light beam and the incidence direction of the detection light beam is equal to a first preset angle and is used for collecting a first scattered light energy signal at the first preset angle position; the second optical sensor is arranged on the detection shell, an included angle between a connecting line of the second optical sensor and the midpoint of the detection light beam and the incidence direction of the detection light beam is equal to a second preset angle, and the second optical sensor is used for collecting a second scattered light energy signal at the position of the second preset angle, and the second preset angle is larger than the first preset angle; The first amplifying and sampling circuit is connected with the first optical sensor and is used for amplifying and sampling the first scattered light energy signal in an analog-to-digital conversion manner; The second amplification sampling circuit is connected with the second optical sensor and is used for amplifying and sampling the second scattered light energy signal in an analog-to-digital conversion manner; The control module is respectively connected with the light beam output module, the first amplifying and sampling circuit and the second amplifying and sampling circuit and is used for controlling the light beam output module to generate stable and adjustable detection light beams, obtaining a sampling value of the first scattered light energy signal and a sampling value of the second scattered light energy signal, calculating according to the sampling value of the first scattered light energy signal to obtain a first particle concentration, calculating according to the sampling value of the second scattered light energy signal to obtain a second particle concentration, comparing the first particle concentration with a preset threshold, outputting the first particle concentration if the first particle concentration is larger than the preset threshold, and outputting the second particle concentration if the first particle concentration is smaller than or equal to the preset threshold.
2. The particulate matter concentration detection apparatus of a dual angle sensor according to claim 1, wherein the first amplification sampling circuit includes a transimpedance amplification circuit, a first post-stage amplification circuit, and a first analog-to-digital converter, an input end of the transimpedance amplification circuit is connected to the first optical sensor, an output end is connected to an input end of the first post-stage amplification circuit, an output end of the first post-stage amplification circuit is connected to an input end of the first analog-to-digital converter, and an output end of the first analog-to-digital converter is connected to the control module.
3. The particulate matter concentration detection apparatus of a dual angle sensor according to claim 2, wherein the transimpedance amplification circuit includes a first resistor and a first operational amplifier having an input impedance higher than a first preset impedance, a bandwidth higher than a first preset bandwidth, and a voltage noise lower than a first preset voltage noise, the positive input terminal and the negative input terminal of the first operational amplifier are respectively connected to the first optical sensor, and the positive input terminal of the first operational amplifier is connected to the output terminal of the first operational amplifier through the first resistor.
4. The particulate matter concentration detection apparatus of a dual angle sensor according to claim 3, wherein the second amplification sampling circuit includes an integration amplification circuit, a second post-stage amplification circuit, and a second analog-to-digital converter, an input end of the integration amplification circuit is connected to the second optical sensor, an output end of the integration amplification circuit is connected to an input end of the second post-stage amplification circuit, an output end of the second post-stage amplification circuit is connected to an input end of the second analog-to-digital converter, an output end of the second analog-to-digital converter is connected to the control module, and a sampling frequency of the second analog-to-digital converter is smaller than a sampling frequency of the first analog-to-digital converter.
5. The particulate matter concentration detection apparatus of a dual angle sensor according to claim 4, wherein the integrating amplification circuit includes an integrating capacitor and a second operational amplifier having an input impedance higher than a second preset impedance and a current noise lower than a first preset current noise, the second preset impedance is larger than the first preset impedance, a positive input terminal and a negative input terminal of the second operational amplifier are respectively connected with the second optical sensor, and a positive input terminal of the second operational amplifier is connected with an output terminal of the second operational amplifier through the integrating capacitor.
6. The particulate matter concentration detection apparatus of the dual angle sensor of claim 5, wherein the integrating amplifying circuit further comprises an analog switch, the analog switch and the integrating capacitor are connected in parallel, and a controlled end of the analog switch is connected with the control module.
7. The particulate matter concentration detection apparatus of the dual angle sensor of claim 1, wherein the light beam output module includes: a laser for generating an initial laser beam; The light path collimation module is used for collimating the initial laser beam, obtaining the detection light beam and outputting the detection light beam; And/or the particulate matter concentration detection device of the dual-angle sensor further comprises a black body, wherein the black body is arranged on the detection shell and is opposite to the detection inlet.
8. A particulate matter concentration detection method, characterized by being applied to the particulate matter concentration detection apparatus of the dual angle sensor according to any one of claims 1 to 7, comprising: acquiring a sampling value of a first scattered light energy signal and a sampling value of a second scattered light energy signal; Calculating to obtain a first particle concentration according to the sampling value of the first scattered light energy signal, and calculating to obtain a second particle concentration according to the sampling value of the second scattered light energy signal; Comparing the first particulate matter concentration with a preset threshold, outputting the first particulate matter concentration if the first particulate matter concentration is greater than the preset threshold, and outputting the second particulate matter concentration if the first particulate matter concentration is less than or equal to the preset threshold.
9. The method of claim 8, wherein the acquiring the sampled value of the first scattered light energy signal and the sampled value of the second scattered light energy signal comprises: And acquiring a sampling value of the first scattered light energy signal at a first sampling frequency, and periodically controlling an analog switch to reset an integration amplifying circuit at a second sampling frequency and acquiring the sampling value of the second scattered light energy signal, wherein the first sampling frequency is larger than the second sampling frequency.
10. The method of claim 8, wherein the first particulate concentration is calculated by: Dividing a target range to be detected of the concentration of the particulate matters into a plurality of sub-ranges, calibrating by using standard samples with the concentration being the endpoints of each sub-range, taking a sampling value of a first scattered light energy signal obtained during calibration as a calibration sampling value, taking the concentration as an abscissa and taking the sampling value as an ordinate, determining the coordinates of the endpoints of each sub-range and calculating to obtain the slope of each sub-range; Acquiring a real-time sampling value of a first scattered light energy signal, comparing the real-time sampling value with a calibration sampling value corresponding to the end point of each sub-range, and if S i ≤S≤S i+1 , obtaining a result of V=K n (S-S i )+B i , wherein V is the calculated concentration of the particulate matters, K n is the slope of the nth sub-range obtained by calibration, S is the real-time sampling value, S i is the calibration sampling value of the ith end point, and B i is the concentration of a standard sample of the ith end point; the second particulate matter concentration is calculated in the same manner as the first particulate matter concentration.

Description

Particulate matter concentration detection device and method for double-angle sensor Technical Field The invention relates to the technical field of concentration detection, in particular to a particulate matter concentration detection device and method of a double-angle sensor. Background The particle concentration detection technology based on the laser scattering method has been widely applied to the fields of environmental monitoring, industrial production, air quality evaluation and the like due to the advantages of high detection speed, convenient operation, wide applicability and the like. At present, a signal amplifying circuit of a particle concentration detection device based on a laser scattering method basically adopts a trans-impedance amplifier, when a small-angle sensor is adopted, the sensor is difficult to capture weak light signals and data fluctuation is large and difficult to count when the small-angle sensor is adopted and the sensor is low in concentration, or the detection sensitivity to weak light is insufficient or the signal to noise ratio is low due to overlarge amplification factor of a circuit and cannot meet the requirement of high-precision detection, so that the prior art cannot simultaneously realize high-precision detection of scenes with high and low particle concentrations. Disclosure of Invention The invention provides a particulate matter concentration detection device and method of a double-angle sensor, which are used for solving the technical problem that the energy ratio of a ring core cannot be flexibly adjusted. In a first aspect, the invention provides a particulate matter concentration detection device of a dual-angle sensor, comprising a light beam output module, a detection light beam detection module and a detection light beam detection module, wherein the light beam output module is used for outputting detection light beams; the particle concentration measuring device comprises a detection shell, a first optical sensor, a second optical sensor, a first amplifying sampling circuit, a control module, a first amplifying sampling circuit and a second amplifying sampling circuit, wherein the detection shell is internally hollow to form a detection cavity, the detection cavity is provided with a detection inlet, a detection light beam enters the detection cavity through the detection inlet, the first optical sensor is arranged on the detection shell, an included angle between a connecting line of the first optical sensor and a midpoint of the detection light beam and an incidence direction of the detection light beam is equal to a first preset angle, the first optical sensor is used for collecting a second scattered light energy signal at a second preset angle, the second preset angle is larger than the first preset angle, the first amplifying sampling circuit is connected with the first optical sensor and used for amplifying and analog-digital converting and sampling the first scattered light energy signal, the second amplifying sampling circuit is connected with the second optical sensor and used for amplifying and analog-digital converting and sampling the second scattered light energy signal, the control module is respectively connected with the first amplifying sampling circuit and the second amplifying sampling circuit and used for obtaining a first scattered light energy signal and a second scattered light energy signal, and calculating the concentration of particles of the first scattered light energy signal and a first scattering particle concentration value and a first particle concentration value and a second particle concentration value, and a first particle concentration value is calculated according to the first particle concentration, and outputting the second particulate matter concentration if the first particulate matter concentration is less than or equal to a preset threshold value. In an alternative embodiment, the first amplifying and sampling circuit includes a transimpedance amplifying circuit, a first post-stage amplifying circuit and a first analog-to-digital converter, the input end of the transimpedance amplifying circuit is connected with the first optical sensor, the output end of the transimpedance amplifying circuit is connected with the input end of the first post-stage amplifying circuit, the output end of the first post-stage amplifying circuit is connected with the input end of the first analog-to-digital converter, and the output end of the first analog-to-digital converter is connected with the control module. In an alternative embodiment, the transimpedance amplifier circuit comprises a first resistor and a first operational amplifier with an input impedance higher than or lower than a first preset impedance, a bandwidth higher than a first preset bandwidth and a voltage noise lower than a first preset voltage noise, wherein a positive input end and a negative input end of the first operational amplifier are respectively conn