Smoke detection device

Abstract

The present invention provides a smoke detection device comprising: a first light source, a second light source, a first receiver, a second receiver, and a control module. The transmitting end of the first light source and the receiving end of the first receiver are arranged opposite each other along a first direction with a first spacing therebetween; the transmitting end of the second light source and the receiving end of the second receiver are arranged opposite each other along a second direction with a second spacing therebetween, the first direction and the second direction being 90 degrees apart, and the first spacing and the second spacing being equal. The control module is connected to the first light source, the second light source, the first receiver, and the second receiver, respectively, and is configured to drive the first and second light sources to emit light, and to obtain a first transmitted light intensity of the first light source and a first scattered light intensity of the second light source received by the first receiver, and a second transmitted light intensity of the second light source and a second scattered light intensity of the first light source received by the second receiver, and to determine a smoke concentration value based on the two transmitted light intensities and the two scattered light intensities. The device provides sensitive and accurate measurement.

Description

Technical Field

[0001] The present invention relates to the technical field of smoke detection, and in particular to a smoke detection device. Background Art

[0002] Lithium batteries are electrochemical energy storage devices with advantages such as high energy density, long battery life, long cycle life, and good rate performance. Furthermore, the use of lithium iron phosphate in the positive electrode of lithium batteries has significantly improved the lifespan and safety of lithium batteries, reducing the cost of battery replacement. However, lithium batteries are flammable and explosive hazardous materials. If the raw materials used in the lithium battery cells are unqualified, the material manufacturing process is not rigorous, the internal resistance is too high, or there is an internal short circuit during the manufacturing process, the lithium battery temperature will rise, causing the battery to produce smoke and even posing a risk of explosion.

[0003] In related technologies, smoke sensors are mostly ion-type smoke detectors. When a fire occurs, aerosol submicron particles and visible smoke released at the beginning enter the detection ionization chamber in large quantities, adsorbing and neutralizing positive and negative ions, causing the ion current to decrease sharply, changing the ion balance state and outputting a detection electrical signal. However, this type of smoke sensor has poor sensitivity and measurement accuracy. Summary of the Invention

[0004] The present invention aims to solve the technical problems in the related art to a certain extent.

[0005] To this end, the purpose of the present invention is to provide a smoke detection device that is sensitive and accurate in measurement, thereby improving the safety and reliability of energy storage power stations and ensuring the smooth operation of energy storage power stations and the stability of the power market.

[0006] To achieve the above objectives, a first embodiment of the present invention provides a smoke concentration detection device, comprising: a first light source, a second light source, a first receiver, a second receiver, and a control module; wherein the transmitting end of the first light source and the receiving end of the first receiver are arranged opposite to each other along a first direction and have a first spacing therebetween; the transmitting end of the second light source and the receiving end of the second receiver are arranged opposite to each other along a second direction and have a second spacing therebetween, the first direction and the second direction are 90 degrees apart, and the first spacing and the second spacing are equal; a first output end of the control module is connected to an input end of the first light source, a second output end of the control module is connected to an input end of the second light source, a first input end of the control module is connected to an output end of the first receiver, and a second input end of the control module is connected to an output end of the second receiver; the control module is configured to drive the first light source and the second light source to emit light, obtain a first transmitted light intensity of the first light source and a first scattered light intensity of the second light source received by the first receiver, and obtain a second transmitted light intensity of the second light source and a second scattered light intensity of the first light source received by the second receiver, and determine a smoke concentration value based on the first transmitted light intensity, the first scattered light intensity, the second transmitted light intensity, and the second scattered light intensity.

[0007] According to an embodiment of the present invention, a smoke concentration detection device comprises a first light source, a second light source, a first receiver, a second receiver, and a control module. The transmitting end of the first light source and the receiving end of the first receiver are arranged opposite each other along a first direction with a first spacing therebetween. The transmitting end of the second light source and the receiving end of the second receiver are arranged opposite each other along a second direction with a second spacing therebetween. The first and second directions are 90 degrees apart, and the first and second spacings are equal. A first output end of the control module is connected to an input end of the first light source, a second output end of the control module is connected to an input end of the second light source, a first input end of the control module is connected to an output end of the first receiver, and a second input end of the control module is connected to an output end of the second receiver. The control module is configured to drive the first and second light sources to emit light, obtain a first transmitted light intensity of the first light source and a first scattered light intensity of the second light source as received by the first receiver, and obtain a second transmitted light intensity of the second light source and a second scattered light intensity as received by the second receiver, and determine a smoke concentration value based on the first transmitted light intensity, the first scattered light intensity, the second transmitted light intensity, and the second scattered light intensity. As a result, the device provides sensitive and accurate measurement, thereby improving the safety and reliability of energy storage power stations, ensuring the smooth operation of energy storage power stations and the stability of the power market.

[0008] In addition, the smoke detection device provided in the embodiment of the present invention may also have the following additional technical features:

[0009] According to one embodiment of the present invention, the control module includes: a first driving unit, a second driving unit, a first collecting unit and a second collecting unit, and a control unit; wherein,

[0010] The control unit is connected to the input end of the first driving unit, the input end of the second driving unit, the output end of the first collecting unit, and the output end of the second collecting unit respectively;

[0011] The output end of the first driving unit is connected to the input end of the first light source, and the first driving unit is used to drive the first light source to emit light;

[0012] The output end of the second driving unit is connected to the input end of the second light source, and the second driving unit is used to drive the second light source to emit light;

[0013] The input end of the first collecting unit is connected to the output end of the first receiver, and the first collecting unit is used to collect the transmitted light of the first light source and the scattered light of the second light source received by the first receiver;

[0014] An input end of the second collecting unit is connected to an output end of the second receiver, and the second collecting unit is used to collect the transmitted light of the second light source and the scattered light of the first light source received by the second receiver.

[0015] According to an embodiment of the present invention, the first driving unit and the second driving unit each include: a first amplifying circuit and a second amplifying circuit; wherein,

[0016] The first end of the first amplifier circuit serves as the input end of the corresponding driving unit, the second end of the first amplifier circuit is connected to the first end of the second amplifier circuit, the second end of the second amplifier circuit is connected to the input end of the corresponding light source, and the third end of the second amplifier circuit is connected to the ground end of the corresponding light source.

[0017] According to one embodiment of the present invention, the first amplifying circuit includes: a first amplifier, a first resistor and a second resistor; wherein,

[0018] The non-inverting input terminal of the first amplifier is respectively connected to the first end of the first resistor and the second end of the second resistor, the second end of the first resistor is grounded, and the second end of the second resistor is connected to the control unit. The inverting input terminal of the first amplifier is connected to the output terminal of the first amplifier and then to the ground, and the output terminal of the first amplifier is connected to the first end of the second amplifying circuit.

[0019] According to one embodiment of the present invention, the second amplifying circuit includes: a second amplifier, a third resistor and a first capacitor; wherein,

[0020] The non-inverting input terminal of the second amplifier is connected to the second terminal of the first amplifier circuit, the inverting input terminal of the second amplifier is respectively connected to the first terminal of the third resistor and the ground terminal of the corresponding light source, the output terminal of the second amplifier is connected to the input terminal of the corresponding light source, the positive power supply terminal of the second amplifier is respectively connected to the voltage source and the first terminal of the first capacitor, the second terminal of the first capacitor is grounded, and the negative power supply terminal of the second amplifier is grounded.

[0021] According to one embodiment of the present invention, the first acquisition unit and the second acquisition unit both include: a third amplifying circuit and a fourth amplifying circuit; wherein,

[0022] The first end of the third amplifier circuit serves as the input end of the corresponding acquisition unit, the second end of the third amplifier circuit is connected to the first end of the fourth amplifier circuit, and the second end of the fourth amplifier circuit is connected to the control unit.

[0023] According to one embodiment of the present invention, the third amplifying circuit includes: a third amplifier, a fourth resistor, a fifth resistor, a sixth resistor, a second capacitor and a third capacitor; wherein,

[0024] The non-inverting input terminal of the third amplifier is connected to the first end of the second capacitor and serves as the first end of the third amplifier circuit. The second end of the second capacitor is grounded. The inverting input terminal of the third amplifier is grounded through the fourth resistor. The inverting input terminal of the third amplifier is connected to the output terminal of the third amplifier through the fifth resistor. The positive power supply terminal of the third amplifier is respectively connected to the first end of the sixth resistor and the first end of the third capacitor. The second end of the sixth resistor is connected to a voltage source. The second end of the third capacitor is grounded. The output terminal of the third amplifier is connected to the first end of the fourth amplifier circuit.

[0025] According to one embodiment of the present invention, the fourth amplifying circuit includes: a fourth amplifier, a seventh resistor and an eighth resistor; wherein,

[0026] The non-inverting input terminal of the fourth amplifier is connected to the second end of the third amplifier circuit, the inverting input terminal of the fourth amplifier is connected to the first end of the seventh resistor and the first end of the eighth resistor respectively, the second end of the seventh resistor is grounded, and the second end of the eighth resistor is connected to the output terminal of the fourth amplifier and then to the control unit.

[0027] According to one embodiment of the present invention, when the control module is used to determine the smoke concentration value according to the first transmitted light intensity, the first scattered light intensity, the second transmitted light intensity, and the second scattered light intensity, the control module includes:

[0028] Obtaining a first product of the first transmitted light intensity and the second transmitted light intensity;

[0029] Obtaining a second product of the first scattered light intensity and the second scattered light intensity;

[0030] obtaining a first difference between the first product and the second product;

[0031] obtaining a ratio between the second product and the first difference;

[0032] Obtaining a value of the square root of the ratio;

[0033] Obtaining a third product of a value of the square root of the ratio and a proportional coefficient;

[0034] The sum of the third product and a set constant is obtained as the smoke concentration value.

[0035] According to one embodiment of the present invention, the device further comprises: an alarm module, the alarm module being connected to the control module;

[0036] The control module is further configured to control the alarm module to send out an alarm signal when the smoke concentration value is greater than a set smoke concentration value.

[0037] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0039] Figure 1 is a schematic diagram of a smoke detection device according to an embodiment of the present invention;

[0040] Figure 2 is a schematic diagram of a smoke detection device according to an embodiment of the present invention;

[0041] Figure 3 is a circuit diagram of a driving unit in a smoke detection device according to an embodiment of the present invention;

[0042] Figure 4 4 is a circuit diagram of a collection unit in a smoke detection device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0043] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0044] The smoke detection device according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0045] Figure 1 is a schematic diagram of a smoke detection device according to an embodiment of the present invention.

[0046] like Figure 1 As shown, the smoke detection device according to the embodiment of the present invention includes: a first light source 10 , a second light source 20 , a first receiver 30 , a second receiver 40 and a control module 50 .

[0047] The transmitting end of the first light source 10 and the receiving end of the first receiver 30 are arranged relative to each other along a first direction, and have a first spacing L1 (i.e., the optical path between the transmitting end of the first light source 10 and the receiving end of the first receiver 30); the transmitting end of the second light source 20 and the receiving end of the second receiver 40 are arranged relative to each other along a second direction, and have a second spacing L2 (i.e., the optical path between the transmitting end of the second light source 20 and the receiving end of the second receiver 40), the first direction and the second direction are 90 degrees, and the first spacing L1 and the second spacing L2 are equal; the first output end of the control module 50 is connected to the input end of the first light source 10, and the second output end of the control module 50 is connected to the input end of the second light source 10. The input end of the source 20 is connected, the first input end of the control module 50 is connected to the output end of the first receiver 30, and the second input end of the control module 50 is connected to the output end of the second receiver 40. The control module 50 is used to drive the first light source 10 and the second light source 20 to emit light, and obtain the first transmitted light intensity of the first light source 10 and the first scattered light intensity of the second light source 20 received by the first receiver 30, the second transmitted light intensity of the second light source 20 and the second scattered light intensity of the first light source 10 received by the second receiver 40, and determine the smoke concentration value according to the first transmitted light intensity, the first scattered light intensity, the second transmitted light intensity and the second scattered light intensity.

[0048] In this embodiment, the first light source 10 and the second light source 20 may both be 650 nm infrared laser sources such as 650 nm infrared laser diodes, and the first receiver 30 and the second receiver 40 may both be photodiodes. The following description uses the example of the first and second light sources 10 and 20 being 650 nm infrared laser sources. The control module 50 drives the first and second light sources 10 and 20 to emit infrared laser light having a wavelength of 650 nm, and collects and converts the transmitted light and scattered light emitted by the first and second light sources 10 and 20, thereby obtaining two signals related to the transmitted light and scattered light. Based on the sine wave, convolution, and correlation characteristics, the control module 50 calculates the transmitted light intensity and scattered light intensity of the smoke gas particles in response to the 650 nm infrared laser light. Thus, a first transmitted light intensity, a first scattered light intensity, a second transmitted light intensity, and a second scattered light intensity are obtained. A first product of the first and second transmitted light intensities and a second product of the first and second scattered light intensities are then obtained. A first difference between the first and second products is calculated, a ratio between the second product and the first difference is obtained, the square root of the ratio is obtained, the third product of the square root of the ratio and the proportionality coefficient is obtained, and the sum of the third product and a set constant is obtained as the smoke concentration value, thereby obtaining the smoke concentration value.

[0049] Furthermore, if Figure 2 As shown, the device further includes an alarm module 60 connected to the control module 50. The control module 50 is further configured to control the alarm module 60 to emit an alarm signal when the smoke concentration exceeds a set smoke concentration value (the set smoke concentration value can be set according to actual needs and is not limited here). The alarm module 60 is an audible and / or visual alarm.

[0050] Therefore, the smoke detection device of the embodiment of the present invention can make a judgment as soon as a problem occurs in the lithium battery and smoke is generated, that is, it is sensitive and accurate in measurement, thereby improving the safety and reliability of the energy storage power station and ensuring the smooth operation of the energy storage power station and the stability of the power market.

[0051] The following combination Figures 2 to 4 The smoke detection device according to the embodiment of the present invention is introduced in detail.

[0052] like Figure 2As shown, the control module 50 includes: a first driving unit 51, a second driving unit 52, a first collecting unit 53, a second collecting unit 54 and a control unit 55; wherein the control unit 55 is respectively connected to the input end of the first driving unit 51, the input end of the second driving unit 52, the output end of the first collecting unit 53 and the output end of the second collecting unit 54; the output end of the first driving unit 51 is connected to the input end of the first light source 10, and the first driving unit 51 is used to drive the first light source 10 to emit light; the output end of the second driving unit 52 is connected to the input end of the second light source 20, and the second driving unit 52 is used to drive the second light source 20 to emit light; the input end of the first collecting unit 53 is connected to the output end of the first receiver 30, and the first collecting unit 53 is used to collect the intensity of the transmitted light of the first light source 10 and the scattered light of the second light source 20 received by the first receiver 30; the input end of the second collecting unit 54 is connected to the output end of the second receiver 40, and the second collecting unit 54 is used to collect the transmitted light of the second light source 20 and the scattered light of the first light source 10 received by the second receiver 40.

[0053] In the embodiment of the present invention, the control unit 55 outputs two sinusoidal wave signals to the first drive unit 51 and the second drive unit 52 respectively. The corresponding drive units convert the sinusoidal wave voltage signals into sinusoidal current signals and drive the corresponding light sources to emit light. The circuit diagram of the first drive unit 51 and the second drive unit 52 is shown in FIG. Figure 3 shown.

[0054] like Figure 3 As shown, the first driving unit 51 and the second driving unit 52 both include: a first amplifier circuit 511 and a second amplifier circuit 512; wherein, the first end of the first amplifier circuit 511 serves as the input end of the corresponding driving unit, the second end of the first amplifier circuit 511 is connected to the first end of the second amplifier circuit 512, the second end of the second amplifier circuit 512 is connected to the input end of the corresponding light source, and the third end of the second amplifier circuit 512 is connected to the ground end of the corresponding light source.

[0055] Continue to refer Figure 3 The first amplifier circuit 511 includes: a first amplifier U1, a first resistor R1 and a second resistor R2; wherein, the non-inverting input terminal of the first amplifier U1 is respectively connected to the first end of the first resistor R1 and the second end of the second resistor R2, the second end of the first resistor R1 is grounded GND, and the second end of the second resistor R2 is connected to the control unit 55, the inverting input terminal of the first amplifier U1 is connected to the output terminal of the first amplifier U1 and then to the ground GND, and the output terminal of the first amplifier U1 is connected to the first end of the second amplifier circuit 512.

[0056] Continue to refer Figure 3The second amplifier circuit 512 includes: a second amplifier U2, a third resistor R3 and a first capacitor C1; wherein, the non-inverting input terminal of the second amplifier U2 is connected to the second terminal of the first amplifier circuit 511, the inverting input terminal of the second amplifier U2 is respectively connected to the first terminal of the third resistor R3 and the ground terminal of the corresponding light source, the output terminal of the second amplifier U2 is connected to the input terminal of the corresponding light source, the positive power supply terminal of the second amplifier U2 is respectively connected to the voltage source and the first terminal of the first capacitor C1, the second terminal of the first capacitor C1 is grounded GND, and the negative power supply terminal of the second amplifier U2 is grounded GND.

[0057] In an embodiment of the present invention, two acquisition units are designed to respectively acquire the transmitted light and scattered light emitted by the corresponding light source. For example, an operational amplifier can be used to amplify and acquire the transmitted light and scattered light emitted by the corresponding light source, and the amplified transmitted light and scattered light are converted into corresponding digital signals, namely, the transmitted light intensity and the scattered light intensity, through the control unit 55. Specifically, the signals include the first transmitted light intensity, the first scattered light intensity, the second transmitted light intensity, and the second scattered light intensity. The circuit diagrams of the first acquisition unit 53 and the second acquisition unit 54 are shown in FIG. Figure 4 shown.

[0058] like Figure 4 As shown, the first acquisition unit 53 and the second acquisition unit 54 both include: a third amplifying circuit 531 and a fourth amplifying circuit 532; wherein, the first end of the third amplifying circuit 531 serves as the input end of the corresponding acquisition unit, the second end of the third amplifying circuit 531 is connected to the first end of the fourth amplifying circuit 532, and the second end of the fourth amplifying circuit 532 is connected to the control unit 55.

[0059] Continue to refer Figure 4 The third amplifier circuit 531 includes: a third amplifier U3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a second capacitor C2 and a third capacitor C3; wherein, the non-inverting input terminal of the third amplifier U3 is connected to the first end of the second capacitor C2 and serves as the first end of the third amplifier circuit 531, the second end of the second capacitor C2 is grounded GND, the inverting input terminal of the third amplifier U3 is grounded GND through the fourth resistor R4, the inverting input terminal of the third amplifier U3 is connected to the output terminal of the third amplifier U3 through the fifth resistor R5, the positive power supply terminal of the third amplifier U3 is respectively connected to the first end of the sixth resistor R6 and the first end of the third capacitor C3, the second end of the sixth resistor R6 is connected to the voltage source, the second end of the third capacitor C3 is grounded GND, and the output terminal of the third amplifier U3 is connected to the first end of the fourth amplifier circuit 532.

[0060] Continue to refer Figure 4The fourth amplifier circuit 532 includes: a fourth amplifier U4, a seventh resistor and an eighth resistor; wherein, the non-inverting input terminal of the fourth amplifier U4 is connected to the second terminal of the third amplifier circuit 531, the inverting input terminal of the fourth amplifier U4 is connected to the first terminal of the seventh resistor and the first terminal of the eighth resistor respectively, the second terminal of the seventh resistor is grounded GND, and the second terminal of the eighth resistor is connected to the output terminal of the fourth amplifier U4 and then connected to the control unit 55.

[0061] The following describes the specific calculation process of the smoke concentration value:

[0062] The refractive index of light in air is about 1.00029. The absorption of 650nm infrared light by air in the near optical path is extremely weak, so the refractive index and absorbance can be ignored. In addition, since the two light sources are directly irradiated to the corresponding receivers, the two light sources are orthogonal and placed in the same optical path, such as Figure 1 As shown, the transmitted light I T The relationship with the incident light I0 is as follows (1):

[0063] (1)

[0064] According to the principles of Rayleigh scattering and Mie scattering, 90-degree scattered light With incident light The relationship is as follows:

[0065] (2)

[0066] in, is the scattering coefficient related to the wavelength of the incident light, N is the particle size of the gas, so the transmitted light With 90 degree scattered light The ratio of the two light intensities is given by the following formula (3):

[0067] (3)

[0068] From this we can get, and The ratio is only related to the particle size and wavelength, and the wavelength is a specific value. The scattering ratio coefficient K ( ).but Wherein, T1 and T2 are the first transmitted light intensity and the second transmitted light intensity respectively; S1 and S2 are the first scattered light intensity and the second scattered light intensity respectively.

[0069] In the following, I1 and I2 represent the light source intensities of the first light source 10 and the second light source 20, respectively, and A1 and A2 represent the integrated gains of the measurement circuits of the first receiver 30 and the second receiver 40, respectively. Then, the reading of the transmitted light intensity of the first light source 10 measured on the first receiver 30, that is, the first transmitted light intensity T1, is expressed by the following formula (4):

[0070] (4)

[0071] The reading of the scattered light intensity of the second light source 20 measured on the first receiver 30, that is, the first scattered light intensity S1 is expressed by the following formula (5):

[0072] (5)

[0073] The reading of the transmitted light intensity of the second light source 20 measured on the second receiver 40, that is, the second transmitted light intensity T2 is expressed by the following formula (6):

[0074] (6)

[0075] The reading of the transmitted light intensity of the first light source 10 measured on the second receiver 40, that is, the second scattered light intensity S2 is expressed by the following formula (7):

[0076] (7)

[0077] From the above formula and , we can get: , we can simplify to get , .

[0078] Since a receiver receives both transmitted light and 90° scattered light, the transmitted light minus the scattered light is the transmitted light of the direct light. From this, the calculation formula for the standard gas concentration can be obtained, as shown in the following formula (8):

[0079] (8)

[0080] The smoke detection device of the present invention is based on the principle that the first light source 10 and the second light source and the first receiver 30 and the second receiver 40 are placed orthogonally with the same optical path. The first light source 10 sends a sinusoidal light signal, and the first receiver 30 and the second receiver 40 receive the light signal at the same time; the second light source 20 sends a sinusoidal light signal, and the first receiver 30 and the second receiver 40 receive the light signal at the same time, thus generating two pairs of sinusoidal wave signals V T1 and V T2 , corresponding to the following formulas (9) and (10):

[0081] (9) (10)

[0082] Among them, A is the amplitude of the AC component of the signal, T is the AC component period of the two signals, 、 is the phase of the AC component, and n is the numerical sequence of the AC signal. 、 is the DC component of the signal, which needs to be greater than or equal to A to ensure V T1 and V T2 Greater than 0. Among them, and Two sinusoidal AC signals are orthogonal. According to the characteristics of sinusoidal waves, if the phase difference between two sinusoidal waves of the same period is 90 degrees, they are orthogonal when the inner product is performed on the sequence length of the complete period, and the result of the inner product is 0.

[0083] Then, the two sinusoidal digital signals are converted into corresponding sinusoidal voltage signals, and the first light source 10 and the second light source 20 are driven by current excitation through the voltage / current conversion module. Since the luminous intensity of the first light source 10 and the second light source 20 is proportional to the excitation current, the light intensity of the first light source 10 and the second light source 20 can be described as follows (11) and (12):

[0084] (11)

[0085] (12)

[0086] in, and are the conversion ratio coefficients from digital signal to light intensity of the first light source 10 and the second light source 20 respectively.

[0087] The light intensity received by the first receiver 30 and the second receiver 40 is amplified and converted to obtain two digital signals V E1 and V E2 Among them, V E1 To receive the digital signal of the transmitted light of the first light source 10 and the scattered light of the second light source 20, V E2 To receive the digital signal of the transmitted light of the second light source 20 and the scattered light of the first light source 10, and combining formulas (1) and (2), the following formulas (13) and (14) can be obtained:

[0088] (13)

[0089] (14)

[0090] Substituting the above formulas (11) and (12) into the above formulas (13) and (14), the following formulas (15) and (16) can be obtained:

[0091] (15) (16)

[0092] During the sampling period, V E1 and V E2 Take a sequence of length N and the orthogonal AC signal on the first light source 10 and the second light source 20: and Demodulation calculations are performed in the form of convolution and correlation principles to obtain the respective readings T1, S1, T2 and S2 of the two receivers for the two light source signals.

[0093] (17)

[0094] (18)

[0095] (19)

[0096] (20)

[0097] Substitute the formula into V E1 、V E2 , we can get the following formula (21):

[0098] (twenty one)

[0099] Since N is a common multiple of T, the first inner product factor in Equation (21) can be known from the properties of trigonometric functions. equal And due to orthogonality, the second inner product factor in Equation (21) is = 0, the third inner product factor in formula (21) is the inner product of the sine function and the DC signal, which is equal to the sum of its own entire cycle, and the result is also equal to 0. Therefore, the following formula (22) can be obtained:

[0100] (twenty two)

[0101] According to the above formula (18), the response amplitude generated by the AC component excitation of the first light source 10 can be demodulated and extracted separately from the signal received by the first receiver 30 facing the first light source 10, without being affected by the second light source 20.

[0102] (twenty three)

[0103] (twenty four)

[0104] (25)

[0105] In this way, when the first light source 10 and the second light source 20 are working at the same time, we can simultaneously demodulate from the corresponding receivers and extract the four AC signal amplitude responses of each receiver to each light source, so that the formula It can be established, and the calculation formula of standard gas concentration can be obtained by using the compensation algorithm .

[0106] Next, the scattering coefficient K is calibrated at two points. The process is as follows:

[0107] Place the smoke detection device in a uniform gas particle concentration of Mmg / m 3 In the container, the transmitted light intensity and scattered light intensity signal values ​​collected from the 650nm wavelength light source are the original signal values ​​T 11 、S 11 、T 12 、S 12 .

[0108] In addition, the smoke detection device is placed in a uniform gas particle concentration of Nmg / m 3 In the container, the transmitted light intensity and scattered light intensity signal values ​​collected from the light source are the original signal values ​​T 21 、S 21 、T 22 、S 22 . You can get the two standard gas concentrations The original values ​​of K M , K N Since the proportional coefficient k and the setting constant b are fixed values, (K M , M) and (K N Substituting these two sets of data (y = kx + b) into the linear function y = kx + b, we can calculate the proportional coefficient k and the set constant b. After calculating the square root of the ratio, we substitute this square root as the unknown quantity x into the linear function to determine the measured smoke concentration.

[0109] In summary, the smoke concentration detection device according to an embodiment of the present invention comprises a first light source, a second light source, a first receiver, a second receiver, and a control module. The transmitting end of the first light source and the receiving end of the first receiver are arranged opposite each other along a first direction with a first spacing therebetween. The transmitting end of the second light source and the receiving end of the second receiver are arranged opposite each other along a second direction with a second spacing therebetween. The first and second directions are 90 degrees apart, and the first and second spacings are equal. The first output end of the control module is connected to the input end of the first light source, the second output end of the control module is connected to the input end of the second light source, the first input end of the control module is connected to the output end of the first receiver, and the second input end of the control module is connected to the output end of the second receiver. The control module is configured to drive the first and second light sources to emit light, obtain the first transmitted light intensity of the first light source and the first scattered light intensity of the second light source received by the first receiver, the second transmitted light intensity of the second light source and the second scattered light intensity of the first light source received by the second receiver, and determine the smoke concentration value based on the first transmitted light intensity, the first scattered light intensity, the second transmitted light intensity, and the second scattered light intensity. As a result, the device has sensitive response and accurate measurement, thereby improving the safety and reliability of energy storage power stations, ensuring the smooth operation of energy storage power stations and the stability of the power market.

[0110] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0111] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

Claims

1. A smoke detection device, characterized in that: include: A first light source, a second light source, a first receiver, a second receiver and a control module; wherein, The transmitting end of the first light source and the receiving end of the first receiver are arranged opposite to each other along a first direction and have a first distance therebetween; The transmitting end of the second light source and the receiving end of the second receiver are arranged opposite to each other along a second direction and have a second distance therebetween, the first direction and the second direction are 90 degrees apart, and the first distance and the second distance are equal; The first output end of the control module is connected to the input end of the first light source, the second output end of the control module is connected to the input end of the second light source, the first input end of the control module is connected to the output end of the first receiver, and the second input end of the control module is connected to the output end of the second receiver. The control module is used to drive the first light source and the second light source to emit light, and obtain a first transmitted light intensity of the first light source and a first scattered light intensity of the second light source received by the first receiver, a second transmitted light intensity of the second light source and a second scattered light intensity of the first light source received by the second receiver, and determine a smoke concentration value based on the first transmitted light intensity, the first scattered light intensity, the second transmitted light intensity, and the second scattered light intensity. When the control module is used to determine the smoke concentration value according to the first transmitted light intensity, the first scattered light intensity, the second transmitted light intensity, and the second scattered light intensity, the control module includes: Obtaining a first product of the first transmitted light intensity and the second transmitted light intensity; Obtaining a second product of the first scattered light intensity and the second scattered light intensity; obtaining a first difference between the first product and the second product; obtaining a ratio between the second product and the first difference; Obtaining a value of the square root of the ratio; Obtaining a third product of a value of the square root of the ratio and a proportional coefficient; The sum of the third product and a set constant is obtained as the smoke concentration value.

2. The smoke detection device according to claim 1, characterized in that: The control module includes: a first driving unit, a second driving unit, a first collecting unit, a second collecting unit and a control unit; wherein, The control unit is connected to the input end of the first driving unit, the input end of the second driving unit, the output end of the first collecting unit, and the output end of the second collecting unit respectively; The output end of the first driving unit is connected to the input end of the first light source, and the first driving unit is used to drive the first light source to emit light; The output end of the second driving unit is connected to the input end of the second light source, and the second driving unit is used to drive the second light source to emit light; The input end of the first collecting unit is connected to the output end of the first receiver, and the first collecting unit is used to collect the transmitted light of the first light source and the scattered light of the second light source received by the first receiver; An input end of the second collecting unit is connected to an output end of the second receiver, and the second collecting unit is used to collect the transmitted light of the second light source and the scattered light of the first light source received by the second receiver.

3. The smoke detection device according to claim 2, characterized in that: The first driving unit and the second driving unit both include: a first amplifying circuit and a second amplifying circuit; wherein, The first end of the first amplifier circuit serves as the input end of the corresponding driving unit, the second end of the first amplifier circuit is connected to the first end of the second amplifier circuit, the second end of the second amplifier circuit is connected to the input end of the corresponding light source, and the third end of the second amplifier circuit is connected to the ground end of the corresponding light source.

4. The smoke detection device according to claim 3, characterized in that: The second amplifying circuit includes: a second amplifier, a third resistor and a first capacitor; wherein, The non-inverting input terminal of the second amplifier is connected to the second terminal of the first amplifier circuit, the inverting input terminal of the second amplifier is respectively connected to the first terminal of the third resistor and the ground terminal of the corresponding light source, the output terminal of the second amplifier is connected to the input terminal of the corresponding light source, the positive power supply terminal of the second amplifier is respectively connected to the voltage source and the first terminal of the first capacitor, the second terminal of the first capacitor is grounded, and the negative power supply terminal of the second amplifier is grounded.

5. The smoke detection device according to claim 2, characterized in that: The first acquisition unit and the second acquisition unit both include: a third amplifying circuit and a fourth amplifying circuit; wherein, The first end of the third amplifier circuit serves as the input end of the corresponding acquisition unit, the second end of the third amplifier circuit is connected to the first end of the fourth amplifier circuit, and the second end of the fourth amplifier circuit is connected to the control unit.

6. The smoke detection device according to claim 5, characterized in that: The third amplifying circuit includes: a third amplifier, a fourth resistor, a fifth resistor, a sixth resistor, a second capacitor and a third capacitor; wherein, The non-inverting input terminal of the third amplifier is connected to the first end of the second capacitor and serves as the first end of the third amplifier circuit. The second end of the second capacitor is grounded. The inverting input terminal of the third amplifier is grounded through the fourth resistor. The inverting input terminal of the third amplifier is connected to the output terminal of the third amplifier through the fifth resistor. The positive power supply terminal of the third amplifier is respectively connected to the first end of the sixth resistor and the first end of the third capacitor. The second end of the sixth resistor is connected to a voltage source. The second end of the third capacitor is grounded. The output terminal of the third amplifier is connected to the first end of the fourth amplifier circuit.

7. The smoke detection device according to claim 5, characterized in that: The fourth amplifying circuit includes: a fourth amplifier, a seventh resistor and an eighth resistor; wherein, The non-inverting input terminal of the fourth amplifier is connected to the second end of the third amplifier circuit, the inverting input terminal of the fourth amplifier is connected to the first end of the seventh resistor and the first end of the eighth resistor respectively, the second end of the seventh resistor is grounded, and the second end of the eighth resistor is connected to the output terminal of the fourth amplifier and then to the control unit.

8. The smoke detection device according to claim 1, characterized in that: The device further comprises: an alarm module, the alarm module being connected to the control module; The control module is further configured to control the alarm module to send out an alarm signal when the smoke concentration value is greater than a set smoke concentration value.

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