Dissolved oxygen concentration monitoring device and system

Abstract

The invention discloses a dissolved oxygen concentration monitoring device and system, and relates to the technical field of dissolved oxygen concentration measurement. The device is used for monitoring the concentration of dissolved oxygen of an aqueous solution circulating in power equipment, and comprises a comprehensive acquisition unit and at least one dissolved oxygen measuring unit, the dissolved oxygen measuring unit is used for generating a dissolved oxygen current signal based on the concentration of dissolved oxygen in an aqueous solution and sending the dissolved oxygen current signal to the comprehensive acquisition unit, and the dissolved oxygen measuring unit is also used for acquiring temperature information at the dissolved oxygen measuring unit and sending the temperature information to the comprehensive acquisition unit; the comprehensive acquisition unit is used for acquiring temperature information and a dissolved oxygen current signal, and performing current-voltage conversion on the dissolved oxygen current signal to obtain a dissolved oxygen voltage signal; and the comprehensive acquisition unit is also used for calculating the concentration information of dissolved oxygen in the aqueous solution based on the temperature information and the dissolved oxygen voltage signal. According to the scheme, the dissolved oxygen concentration monitoring capability can be enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of dissolved oxygen concentration measurement, and in particular to a dissolved oxygen concentration monitoring device and system. Background Art

[0002] At present, dissolved oxygen in aqueous solutions in power systems of nuclear power plants and thermal power plants is the main cause of corrosion of power equipment, and the migration of corrosion products will endanger the safe operation of power equipment. Therefore, in order to reduce equipment corrosion and ensure the service life and operating efficiency of power equipment, it is necessary to control the dissolved oxygen in the power system. Here, the premise of controlling dissolved oxygen in the power system is to monitor the dissolved oxygen concentration of the aqueous solution circulating in the power equipment online to provide data support for the control work.

[0003] Currently, the existing method for monitoring dissolved oxygen concentration is to install a dissolved oxygen sensor in a pipeline where an aqueous solution flows in an electrical device, collect the dissolved oxygen current signal output by the dissolved oxygen sensor based on an electrochemical method, convert the dissolved oxygen current signal into a dissolved oxygen voltage signal, and determine the concentration of dissolved oxygen in the aqueous solution through a monitoring device based on the size of the dissolved oxygen voltage signal.

[0004] However, the various power equipment in nuclear power plants and thermal power plants are in relatively extreme operating temperatures. Too high or too low a temperature may affect the output of the dissolved oxygen sensor, resulting in a large error in the dissolved oxygen concentration, and thus resulting in a weaker monitoring capability for the dissolved oxygen concentration. Summary of the invention

[0005] In view of this, the present application provides a dissolved oxygen concentration monitoring device and system, the main purpose of which is to solve the technical problem of weak monitoring capability of dissolved oxygen concentration.

[0006] According to a first aspect of the present invention, there is provided a dissolved oxygen concentration monitoring device for monitoring the dissolved oxygen concentration of an aqueous solution circulating in an electric power device, the device comprising a comprehensive acquisition unit and at least one dissolved oxygen measurement unit;

[0007] The dissolved oxygen measurement unit is used to generate a dissolved oxygen current signal based on the concentration of dissolved oxygen in the aqueous solution, and send the dissolved oxygen current signal to the comprehensive acquisition unit;

[0008] The dissolved oxygen measuring unit is also used to collect temperature information of the dissolved oxygen measuring unit and send the temperature information to the comprehensive collection unit;

[0009] The comprehensive acquisition unit is used to convert the dissolved oxygen current signal into a dissolved oxygen voltage signal, and calculate the concentration information of dissolved oxygen in the aqueous solution based on the temperature information and the dissolved oxygen voltage signal.

[0010] Optionally, the comprehensive acquisition unit calculates the concentration information of dissolved oxygen in the aqueous solution based on the temperature information and the dissolved oxygen voltage signal, including: the comprehensive acquisition unit obtains a preset dissolved oxygen correction coefficient, and corrects the dissolved oxygen voltage signal based on the dissolved oxygen correction coefficient to obtain the corrected dissolved oxygen voltage signal; calculates the oxygen partial pressure value based on the temperature information and the corrected dissolved oxygen voltage signal, and calculates the concentration information based on the oxygen partial pressure value and the temperature information.

[0011] Optionally, the dissolved oxygen measurement unit includes a circulation cell, a temperature sensor and a dissolved oxygen sensor; the circulation cell has a hollow inner cavity, and the hollow inner cavity is connected to a pipeline for conveying the aqueous solution so that the aqueous solution can flow into the hollow inner cavity and flow out of the hollow inner cavity; the dissolved oxygen sensor is used to generate a dissolved oxygen current signal based on the concentration of dissolved oxygen in the aqueous solution in the hollow inner cavity, and send the dissolved oxygen current signal to the comprehensive acquisition unit; the temperature sensor is used to collect the temperature value of the dissolved oxygen sensor, and send the temperature value as the temperature information to the comprehensive acquisition unit.

[0012] Optionally, the dissolved oxygen sensor comprises a sensor housing and a sensor electrode connected to the integrated collection unit, the sensor housing comprising a hollow chamber and a sensor housing opening communicating with the hollow chamber, the sensor electrode being arranged in the hollow chamber; the circulation cell comprises a circulation cell shell, the hollow inner cavity being arranged in the circulation cell shell, the circulation cell shell comprising a liquid inlet, a liquid outlet and a sensor docking port; the sensor docking port is communicated with the sensor housing opening so that the hollow chamber is communicated with the hollow inner cavity; the liquid inlet is communicated with the pipeline so that the aqueous solution in the pipeline can flow into the hollow inner cavity, and the liquid outlet is communicated with the pipeline so that the aqueous solution in the hollow inner cavity can flow out to the pipeline.

[0013] Optionally, the opening of the sensor housing is covered with a waterproof and breathable membrane, which is used to isolate the aqueous solution in the hollow inner cavity from the hollow chamber and allow the gas in the aqueous solution to flow into the hollow chamber; the sensor electrode includes a working electrode and a counter electrode respectively connected to the comprehensive acquisition unit, and the hollow chamber is filled with an electrolyte; the comprehensive acquisition unit is used to output a working voltage to the counter electrode, so that the working electrode outputs the dissolved oxygen current signal.

[0014] Optionally, the working electrode includes a first electrode and a second electrode; the first electrode is arranged in a hollow column surrounded by the second electrode, the first end of the hollow column has an electrolyte flow port, and the second end of the hollow column extends out of the sensor housing; the first electrode is connected to the comprehensive acquisition unit, and is used to send the dissolved oxygen current signal to the comprehensive acquisition unit.

[0015] Optionally, the integrated acquisition unit includes a first conditioning circuit, a data acquisition circuit and a microprocessor; the first conditioning circuit is connected to the working electrode of the dissolved oxygen sensor, and is used to obtain the dissolved oxygen current signal from the working electrode and convert the dissolved oxygen current signal into the dissolved oxygen voltage signal; the data acquisition circuit is respectively connected to the temperature sensor and the first conditioning circuit, and is used to perform analog-to-digital conversion on the obtained dissolved oxygen voltage signal and the temperature information to obtain the dissolved oxygen voltage signal and the temperature information in the form of digital signals, and send the dissolved oxygen voltage signal and the temperature information in the form of digital signals to the microprocessor; the microprocessor is used to calculate the concentration information of dissolved oxygen in the aqueous solution based on the temperature information and the dissolved oxygen voltage signal.

[0016] Optionally, the comprehensive acquisition unit also includes a communication circuit; the communication circuit is connected to the microprocessor, and the communication circuit is used to connect the microprocessor to a remote host computer to establish a communication connection between the host computer and the microprocessor.

[0017] Optionally, the integrated acquisition unit also includes a drive circuit; the drive circuit is respectively connected to the microprocessor, the dissolved oxygen sensor and the temperature sensor; the microprocessor is also used to send a temperature acquisition signal to the drive circuit, so that the drive circuit sends a temperature drive current to the temperature sensor, so that the temperature sensor enters a working state; the microprocessor is also used to send a dissolved oxygen acquisition signal to the drive circuit, so that the drive circuit sends an electrode drive voltage to the dissolved oxygen sensor, so that the dissolved oxygen sensor enters a working state.

[0018] According to a second aspect of the present invention, a dissolved oxygen concentration monitoring system is provided, which includes a main control unit and a dissolved oxygen concentration monitoring device as described above; the main control unit is connected to the comprehensive acquisition unit of the dissolved oxygen concentration monitoring device, and is used to establish a communication connection with the comprehensive acquisition unit; the system also includes a power supply module; the power supply module is respectively connected to the main control unit and the comprehensive acquisition unit, and is used to access an external power supply and supply power to the main control unit and the comprehensive acquisition unit.

[0019] The present invention provides a dissolved oxygen concentration monitoring device and system, which can incorporate the temperature information of the dissolved oxygen measurement unit into the calculation process of the dissolved oxygen concentration information, correct the dissolved oxygen voltage signal, and obtain a more accurate dissolved oxygen concentration monitoring result, thereby significantly enhancing the monitoring capability of the dissolved oxygen concentration.

[0020] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0022] Figure 1 One of the structural schematic diagrams of a dissolved oxygen concentration monitoring device provided by an embodiment of the present invention is shown;

[0023] Figure 2 A second structural schematic diagram of a dissolved oxygen concentration monitoring device provided by an embodiment of the present invention is shown;

[0024] Figure 3 A third structural schematic diagram of a dissolved oxygen concentration monitoring device provided by an embodiment of the present invention is shown;

[0025] Figure 4 One of the structural schematic diagrams of a dissolved oxygen sensor provided by an embodiment of the present invention is shown;

[0026] Figure 5 A second structural schematic diagram of a dissolved oxygen sensor provided by an embodiment of the present invention is shown;

[0027] Figure 6 A schematic diagram of the structure of a comprehensive acquisition unit provided by an embodiment of the present invention is shown;

[0028] Figure 7 A structural schematic diagram of a dissolved oxygen concentration monitoring system provided by an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0029] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict.

[0030] In one embodiment, Figure 1As shown, a dissolved oxygen concentration monitoring device is provided, and the device is used to monitor the dissolved oxygen concentration of an aqueous solution circulating in an electric power device for explanation. The dissolved oxygen concentration monitoring device includes a comprehensive acquisition unit 100 and at least one dissolved oxygen measuring unit 200. The dissolved oxygen measuring unit 200 is a sensor that can collect the dissolved oxygen concentration in the aqueous solution based on the electrochemical principle. The sensor generates a dissolved oxygen current signal for characterizing the concentration of dissolved oxygen in the aqueous solution based on the concentration of dissolved oxygen in the aqueous solution through the electrochemical principle. Furthermore, the dissolved oxygen measuring unit 200 can be arranged at a pipeline 500 for conveying aqueous solution in an electric power device or a power station to collect the dissolved oxygen concentration of the aqueous solution circulating in the electric power device or the power station.

[0031] Specifically, the dissolved oxygen measurement unit 200 is used to generate a dissolved oxygen current signal based on the concentration of dissolved oxygen in the aqueous solution, and send the dissolved oxygen current signal to the comprehensive acquisition unit 100. Specifically, the dissolved oxygen measurement unit 200 has a cathode and an anode, which are placed in the aqueous solution. Further, the dissolved oxygen molecules diffuse to the cathode surface and react with the electrode material (such as silver, gold or platinum, etc.) to generate a dissolved oxygen current signal. Here, the intensity of this current is proportional to the concentration of dissolved oxygen in the aqueous solution.

[0032] Furthermore, the dissolved oxygen measuring unit 200 is also used to collect temperature information of the dissolved oxygen measuring unit 200 and send the temperature information to the comprehensive collection unit 100; specifically, a temperature sensor (not shown in the figure) may be provided in the dissolved oxygen measuring unit 200 to collect the temperature value of the dissolved oxygen measuring unit 200 and send the temperature value as temperature information to the comprehensive collection unit 100.

[0033] Furthermore, the comprehensive acquisition unit 100 is used to convert the dissolved oxygen current signal into a dissolved oxygen voltage signal, and calculate the concentration information of dissolved oxygen in the aqueous solution based on the temperature information and the dissolved oxygen voltage signal. Here, the dissolved oxygen voltage signal converted from the dissolved oxygen current signal is proportional to the concentration of dissolved oxygen in the aqueous solution, and the concentration of dissolved oxygen in the aqueous solution can be calculated by the size of the dissolved oxygen voltage signal. Further, the dissolved oxygen voltage signal can be corrected based on the temperature information. Here, the compensation value of the dissolved oxygen voltage signal at each temperature can be determined based on experiments or tests. In the actual monitoring process, the compensation value corresponding to the temperature information can be determined by the temperature information, and the dissolved oxygen voltage signal can be corrected according to the compensation value, and then the concentration information of dissolved oxygen in the aqueous solution can be determined according to the corrected dissolved oxygen voltage signal.

[0034] The dissolved oxygen concentration monitoring device provided in this embodiment can incorporate the temperature information of the dissolved oxygen measurement unit into the calculation process of the dissolved oxygen concentration information, and correct the dissolved oxygen voltage signal to obtain a more accurate dissolved oxygen concentration monitoring result, thereby significantly enhancing the monitoring capability of the dissolved oxygen concentration.

[0035] In an optional embodiment, the comprehensive acquisition unit calculates the concentration information of dissolved oxygen in the aqueous solution based on the temperature information and the dissolved oxygen voltage signal in a manner including:

[0036] First, the comprehensive acquisition unit obtains a preset dissolved oxygen correction coefficient, and corrects the dissolved oxygen voltage signal based on the dissolved oxygen correction coefficient to obtain the corrected dissolved oxygen voltage signal; wherein the dissolved oxygen correction coefficient can be obtained by conducting experiments or tests on the dissolved oxygen concentration monitoring device in a test environment in advance.

[0037] Specifically, the method for obtaining the dissolved oxygen correction coefficient includes: first, obtaining a test dissolved oxygen voltage signal generated by the comprehensive acquisition unit of the dissolved oxygen concentration monitoring device under a test environment, wherein the test environment is that the dissolved oxygen measuring unit connected to the comprehensive acquisition unit is at a test temperature value, the concentration of the gas in the gas environment where the dissolved oxygen measuring unit is located is a preset standard gas concentration, and the pressure of the gas in the gas environment is a preset gas standard pressure; here, the values ​​of the test temperature value, the preset standard gas concentration, and the preset gas standard pressure can be determined according to actual conditions.

[0038] Specifically, the dissolved oxygen concentration monitoring device can be set in the test environment and perform concentration monitoring work, the dissolved oxygen measurement unit is placed under a preset standard gas concentration and a preset gas standard pressure, the temperature of the dissolved oxygen measurement unit is set to a test temperature value, and the test dissolved oxygen current signal output by the dissolved oxygen measurement unit is obtained. Furthermore, the comprehensive acquisition unit performs current-voltage conversion on the test dissolved oxygen current signal to obtain a test dissolved oxygen voltage signal.

[0039] Then, the atmospheric pressure value at the location of the comprehensive acquisition unit is obtained; specifically, an atmospheric pressure gauge may be provided at the comprehensive acquisition unit to acquire the atmospheric pressure value at the location of the comprehensive acquisition unit when generating the test dissolved oxygen voltage signal.

[0040] Then, based on the preset standard gas concentration, the preset gas standard pressure, the atmospheric pressure value and the test temperature value, the theoretical voltage value is calculated; wherein the theoretical voltage value is the theoretical value of the test dissolved oxygen voltage signal generated by the comprehensive acquisition unit under the test environment. Specifically, the theoretical voltage value can be calculated according to Formula 1:

[0041] U理 =(C 理 +P 气 )×C 气 ×exp(-1 / T)(1)

[0042] Among them, U 理 is the theoretical voltage value, C 理 is the preset standard gas concentration, P 气 is the preset gas standard pressure, C 气 is the atmospheric pressure value, and T is the test temperature value. Further, the test dissolved oxygen current signal output by the dissolved oxygen measurement unit when the gas concentration is zero can also be measured, and the test dissolved oxygen current signal can be converted into a test dissolved oxygen voltage signal, and the test dissolved oxygen voltage signal can be determined as the residual voltage of the dissolved oxygen measurement unit.

[0043] Finally, the ratio of the test dissolved oxygen voltage signal to the theoretical voltage value is calculated to obtain the dissolved oxygen correction coefficient. Specifically, the dissolved oxygen correction coefficient can be calculated according to Formula 2:

[0044] α=U 测 / U 理 (2)

[0045] Among them, α is the dissolved oxygen correction factor, U 测 To test the dissolved oxygen voltage signal.

[0046] Further, after obtaining the dissolved oxygen correction coefficient, the dissolved oxygen voltage signal is multiplied by the dissolved oxygen correction coefficient to obtain the corrected dissolved oxygen voltage signal. Here, the dissolved oxygen voltage signal can also be subtracted from the residual voltage and then multiplied by the dissolved oxygen correction coefficient to obtain the corrected dissolved oxygen voltage signal to improve the accuracy of dissolved oxygen concentration calculation.

[0047] Further, based on the temperature information and the corrected dissolved oxygen voltage signal, the oxygen partial pressure value is calculated, and based on the oxygen partial pressure value and the temperature information, the concentration information is calculated. Specifically, the oxygen partial pressure value can be calculated according to Formula 3:

[0048] P 氧 =U 修 ÷exp (-1 / T 温 ) (3)

[0049] Among them, P 氧 is the oxygen partial pressure value, U 修 is the corrected dissolved oxygen voltage signal, T 温 It is the temperature information.

[0050] Furthermore, the concentration information can be calculated based on the oxygen partial pressure value and temperature information according to Henry's law. The embodiment provided by the present application can correct the dissolved oxygen voltage signal by the dissolved oxygen correction coefficient and temperature information, and calculate the concentration information of dissolved oxygen in the aqueous solution based on the corrected dissolved oxygen voltage signal, and can incorporate information such as the temperature of the dissolved oxygen measurement unit into the calculation process of the dissolved oxygen concentration, thereby significantly enhancing the monitoring accuracy of the dissolved oxygen concentration monitoring device for the dissolved oxygen concentration.

[0051] In an optional embodiment, if Figure 2 As shown, the dissolved oxygen measurement unit 200 includes a dissolved oxygen sensor 210 , a temperature sensor 220 , and a flow cell 230 .

[0052] Specifically, the circulation pool 230 has a hollow inner cavity 232, and the hollow inner cavity 232 is connected to the pipeline 500 for conveying the aqueous solution, so that the aqueous solution can flow into the hollow inner cavity 232 and flow out of the hollow inner cavity 232. Here, when the aqueous solution flows in the pipeline 500, the aqueous solution in the pipeline 500 will flow into the hollow inner cavity 232 through the multiple flow holes between the hollow inner cavity 232 and the pipeline 500, filling the hollow inner cavity 232. At the same time, the aqueous solution in the hollow inner cavity 232 will also flow out of the hollow inner cavity 232 from the flow holes under the water pressure of the aqueous solution that subsequently flows into the hollow inner cavity 232, so that the aqueous solution in the hollow inner cavity 232 is continuously updated. Here, the aqueous solution capacity of the hollow inner cavity 232 is within 10 ml.

[0053] Further, the dissolved oxygen sensor 210 is used to generate a dissolved oxygen current signal based on the concentration of dissolved oxygen in the aqueous solution in the hollow inner cavity 232, and send the dissolved oxygen current signal to the integrated acquisition unit 100. Here, the dissolved oxygen sensor 210 can be arranged inside the hollow inner cavity 232. Further, the dissolved oxygen sensor 210 can also be arranged on the outer surface of the flow cell housing 231 of the flow cell 230, and the dissolved oxygen concentration of the aqueous solution in the hollow inner cavity 232 is collected by extending the electrode for collecting the dissolved oxygen concentration into the hollow inner cavity 232 to generate a dissolved oxygen current signal.

[0054] Further, the temperature sensor 220 is used to collect the temperature value of the dissolved oxygen sensor 210, and send the temperature value as the temperature information to the comprehensive collection unit 100. Here, the temperature sensor 220 can be arranged on the outer surface of the dissolved oxygen sensor 210, and the temperature measuring element of the temperature sensor 220 is in contact with the sensor housing of the dissolved oxygen sensor 210 to collect the temperature value of the dissolved oxygen sensor 210.

[0055] The real-time example provided in the present application can significantly improve the dissolved oxygen concentration measurement effect of the dissolved oxygen concentration monitoring device by introducing the aqueous solution in the pipeline into a circulation pool and then measuring the dissolved oxygen concentration of the aqueous solution in the circulation pool, compared with directly inserting the dissolved oxygen sensor into the pipeline and directly measuring the dissolved oxygen concentration of the aqueous solution in the pipeline.

[0056] In an optional embodiment, if Figure 3 As shown, the dissolved oxygen sensor 210 has a sensor housing 212 and a sensor electrode 211 connected to the integrated acquisition unit 100, the sensor housing 212 has a hollow chamber 213 and a sensor housing opening 214 communicating with the hollow chamber 213, and the sensor electrode 211 is disposed in the hollow chamber 213. Further, the temperature sensor 220 may be disposed on the outer surface of the sensor housing 212 of the dissolved oxygen sensor 210.

[0057] Further, the circulation cell 230 has a circulation cell housing 231, the hollow inner cavity 232 is arranged in the circulation cell housing 231, and the circulation cell housing 231 has a sensor docking port 235 connected to the hollow inner cavity 232, and a liquid inlet 233 and a liquid outlet 234 connected to the pipeline 500. Further, the sensor docking port 235 is docked and connected with the sensor housing opening 214, so that the hollow chamber 213 is connected with the hollow inner cavity 232. Further, the sensor docking port 235 and the sensor housing opening 214 can be sealed by an O-ring. Here, the material of the circulation cell housing 231 is a material with strong corrosion resistance, such as stainless steel, nickel-based alloy, etc., and the O-ring is made of a material with good oxidation resistance, corrosion resistance, insulation and radiation resistance, such as fluororubber, ethylene propylene rubber, etc., so that the dissolved oxygen measurement unit 200 has the ability to work continuously and stably under high pressure conditions of 0 to 15 MPa.

[0058] Further, the liquid inlet 233 is communicated with the pipeline 500 so that the aqueous solution in the pipeline 500 can flow into the hollow inner cavity 232, and the liquid outlet 234 is communicated with the pipeline 500 so that the aqueous solution in the hollow inner cavity 232 can flow out of the pipeline 500. Here, the liquid inlet 233, the liquid outlet 234 and the pipeline 500 can also be sealed by an O-ring.

[0059] Here, the oxygen in the aqueous solution in the hollow inner cavity 232 can flow into the hollow chamber 213 and undergo an electrochemical reaction with the sensor electrode 211 in the hollow chamber 213, and a dissolved oxygen current signal is generated by the sensor electrode 211, and the integrated acquisition unit 100 can receive the dissolved oxygen current signal. In the embodiment provided by the present application, the dissolved oxygen sensor is docked with the circulation pool, so that the sensor electrode in the dissolved oxygen sensor can undergo an electrochemical reaction with the oxygen in the aqueous solution in the hollow inner cavity to generate a dissolved oxygen current signal for characterizing the dissolved oxygen concentration in the aqueous solution, which can realize online monitoring of the dissolved oxygen concentration of the aqueous solution in the high-voltage power equipment circuit of a nuclear power plant or a thermal power plant, reflect the oxygen content in the reaction circuit in real time, and provide a basis for water quality control in the circuit.

[0060] Furthermore, Figure 4 and Figure 5 A cross-sectional view of a dissolved oxygen sensor is given. In an optional embodiment, as Figure 4 As shown, the sensor housing opening 214 is covered with a waterproof breathable membrane 215 for isolating the aqueous solution in the hollow inner cavity (not shown) from the hollow chamber 213 and allowing the gas in the aqueous solution to flow into the hollow chamber 213 .

[0061] Further, the sensor electrode includes a working electrode 2111 and a counter electrode 2112 respectively connected to the integrated collection unit, wherein the working electrode 2111 can be arranged at the center of the hollow chamber 213, and the counter electrode 2112 surrounds the working electrode 2111 at the center. Further, the hollow chamber 213 is filled with an electrolyte.

[0062] Further, the integrated acquisition unit is used to output a working voltage to the counter electrode 2112, so that the working electrode 2111 outputs the dissolved oxygen current signal. Here, the counter electrode 2112 can be connected to a comprehensive acquisition unit (not shown in the figure). When the dissolved oxygen sensor needs to collect dissolved oxygen concentration, the comprehensive acquisition unit can apply a voltage to the counter electrode 2112 to generate a voltage difference between the counter electrode 2112 and the working electrode 2111, so that the counter electrode 2112 and the working electrode 2111 undergo an electrochemical reaction, and the working electrode 2111 outputs the dissolved oxygen current signal to the integrated acquisition unit.

[0063] Furthermore, the electrolyte can be potassium hydroxide, potassium chloride or a mixed solution of potassium hydroxide and potassium chloride, the working electrode 2111 can be made of precious metal materials such as gold, silver, platinum, etc., and the material of the counter electrode 2112 can be silver. When the counter electrode 2112 obtains voltage, the electrochemical reaction occurring at the counter electrode 2112 is 4Ag+4Cl--4e-=4AgCl, and the electrochemical reaction occurring at the working electrode 2111 is O2+2H2O+4e-=4OH-, so that the working electrode 2111 can output electrons to generate current.

[0064] In the embodiment provided by the present application, liquid isolation is established between the sensor electrode and the circulation pool through a waterproof and breathable membrane, and at the same time, oxygen in the aqueous solution in the circulation pool passes through the waterproof and breathable membrane into the dissolved oxygen sensor to produce an electrochemical reaction with the working electrode and the counter electrode, thereby preventing the electrolyte from being contaminated by the aqueous solution, generating a dissolved oxygen current signal on the working electrode, facilitating the subsequent calculation of the dissolved oxygen concentration, and improving the signal output efficiency of the dissolved oxygen sensor.

[0065] In an optional embodiment, if Figure 5 As shown, the working electrode 2111 includes a first electrode EL1 and a second electrode EL2.

[0066] The first electrode EL1 is disposed in a hollow column surrounded by the second electrode EL2, and the first end of the hollow column has an electrolyte flow port, so that the electrolyte can flow into the gap between the first electrode EL1 and the second electrode EL2. Furthermore, the second end of the hollow column extends out of the sensor housing 212.

[0067] Furthermore, the first electrode EL1 is connected to the integrated acquisition unit (not shown in the figure) to send the dissolved oxygen current signal to the integrated acquisition unit. In the embodiment provided by the present application, the first electrode is surrounded by the second electrode, and the first electrode outputs the dissolved oxygen current signal, which can eliminate the interference of the external environment on the output current signal of the first electrode, thereby improving the dissolved oxygen monitoring accuracy of the dissolved oxygen concentration monitoring device.

[0068] In an optional embodiment, if Figure 6 As shown, the integrated acquisition unit 100 includes a first conditioning circuit 110, a data acquisition circuit 120 and a microprocessor 130. The microprocessor 130 can be a computing device with computing capabilities such as an integrated chip to achieve logic control such as drive output, data acquisition, communication transmission, and filter and temperature compensation for the collected data. Furthermore, the software code in the microprocessor 130 is jointly written in Verilog HDL and C language, and is compiled and downloaded through software.

[0069] Furthermore, the first conditioning circuit 110 is connected to the working electrode (not shown) of the dissolved oxygen sensor, and is used to obtain the dissolved oxygen current signal from the working electrode and convert the dissolved oxygen current signal into the dissolved oxygen voltage signal. Here, the first conditioning circuit 110 uses an operational amplifier to perform current-voltage conversion, filtering, voltage following, and impedance conversion on the dissolved oxygen current signal detected by the dissolved oxygen sensor, and then outputs a dissolved oxygen concentration voltage signal to the data acquisition circuit 120.

[0070] Furthermore, the data acquisition circuit 120 is connected to the temperature sensor (not shown in the figure) and the first conditioning circuit 110, respectively, and is used to perform analog-to-digital conversion on the acquired dissolved oxygen voltage signal and the temperature information to obtain the dissolved oxygen voltage signal and the temperature information in the form of digital signals, and send the dissolved oxygen voltage signal and the temperature information in the form of digital signals to the microprocessor 130; here, the data acquisition circuit 120 uses a high-precision, low-noise 24-bit analog-to-digital converter to collect the dissolved oxygen concentration voltage signal output by the first conditioning circuit 110, and uses a high-precision, low-noise 24-bit analog-to-digital converter to collect the temperature voltage signal detected by the temperature sensor for characterizing the temperature information.

[0071] Furthermore, the microprocessor 130 is used to calculate the concentration information of dissolved oxygen in the aqueous solution based on the temperature information and the dissolved oxygen voltage signal. The embodiment provided by the present application can optimize the signal and convert the current to voltage of the collected dissolved oxygen current signal through the first conditioning circuit, and perform analog-to-digital conversion on the dissolved oxygen voltage signal and the temperature voltage signal used to characterize the temperature information through the data acquisition circuit to obtain a signal that can be processed by the microprocessor, so as to improve the efficiency of the dissolved oxygen concentration monitoring device in outputting the dissolved oxygen concentration.

[0072] In an optional embodiment, if Figure 6As shown, the comprehensive acquisition unit 100 also includes a communication circuit 140. Specifically, the communication circuit 140 is connected to the microprocessor 130, and the communication circuit 140 is used to connect the microprocessor 130 to a remote host computer (not shown in the figure) to establish a communication connection between the host computer and the microprocessor 130. Among them, the host computer can be a computer terminal used by remote monitoring personnel. Here, the communication circuit 140 can be connected to the host computer through cables such as Ethernet cables, RS485 buses and optical fibers. Further, the communication circuit 140 uses a low-power isolation transceiver, and the communication circuit 140 is used to receive the control instructions issued by the microprocessor 130, and upload the dissolved oxygen concentration information obtained by the microprocessor 130 to the host computer. Further, the comprehensive acquisition unit 100 also includes a dissolved oxygen concentration output circuit 180, which is used to obtain dissolved oxygen concentration information from the microprocessor 130 in real time, and output a 4-20mA current signal used to characterize the dissolved oxygen concentration to an external instrumentation system in real time.

[0073] Further, such as Figure 6 As shown, the integrated acquisition unit 100 also includes an atmospheric pressure gauge 170, wherein the atmospheric pressure gauge 170 uses a high-precision absolute pressure sensor to achieve real-time detection of the atmospheric pressure value of the environment in which the integrated acquisition unit 100 is located, and sends the atmospheric pressure value to the integrated acquisition unit 100. The embodiment provided by the present application can establish a connection between the integrated acquisition unit and a remote host computer through a communication circuit, so as to send the dissolved oxygen concentration information obtained by the integrated acquisition unit to the host computer, and enable relevant staff to remotely control the integrated acquisition unit through the host computer, thereby improving the operability of the dissolved oxygen concentration monitoring device.

[0074] In an optional embodiment, if Figure 6 As shown, the integrated acquisition unit 100 also includes a driving circuit 150. Here, the driving circuit 150 can use a high-precision, low-noise 24-bit analog-to-digital converter to output a 500μA temperature driving current, and a high-precision 16-bit digital-to-analog converter to output an 800mV electrode driving voltage.

[0075] Furthermore, the drive circuit 150 is respectively connected to the microprocessor 130, the pair of electrodes (not shown in the figure) and the temperature sensor (not shown in the figure); specifically, the microprocessor 130 is also used to send a temperature acquisition signal to the drive circuit 150, so that the drive circuit 150 sends a temperature drive current to the temperature sensor, so that the temperature sensor enters a working state; in addition, the microprocessor 130 is also used to send a dissolved oxygen acquisition signal to the drive circuit 150, so that the drive circuit 150 sends an electrode drive voltage to the dissolved oxygen sensor, so that the dissolved oxygen sensor enters a working state.

[0076] Furthermore, a second conditioning circuit 160 may be provided between the driving circuit 150 and the temperature sensor and the counter electrode. The second conditioning circuit 160 may be an operational amplifier. The second conditioning circuit 160 receives an electrode driving voltage from the driving circuit 150, and performs a DC drive on the dissolved oxygen sensor after voltage following, power amplification, and impedance conversion. Furthermore, the second conditioning circuit 160 receives a temperature driving current from the driving circuit 150, and performs a DC drive on the temperature sensor after voltage following, power amplification, and impedance conversion.

[0077] In the embodiment provided by the present application, when it is necessary to put the dissolved oxygen measurement unit into a working state, relevant staff can control the microprocessor to control the driving circuit to send driving information to the temperature sensor and the dissolved oxygen sensor, so that the temperature sensor and the dissolved oxygen sensor respectively collect temperature information and dissolved oxygen current signals, thereby improving the operability of the dissolved oxygen concentration monitoring device.

[0078] The dissolved oxygen concentration monitoring device provided in this embodiment can continuously receive the aqueous solution in the pipeline of the power equipment through the circulation pool, so that the aqueous solution in the power equipment is renewed and circulated in the circulation pool to continuously collect the dissolved oxygen concentration of the aqueous solution; further, the operating status of the temperature sensor and the dissolved oxygen sensor can be controlled by the microprocessor in the comprehensive acquisition unit, and the temperature information of the dissolved oxygen sensor is incorporated into the calculation process of the dissolved oxygen concentration information, and the dissolved oxygen voltage signal is corrected to obtain a more accurate dissolved oxygen concentration monitoring result, and the dissolved oxygen concentration monitoring result can be sent to the host computer so that relevant staff can view the dissolved oxygen concentration monitoring result, and the dissolved oxygen concentration monitoring device can be remotely controlled, which significantly enhances the monitoring capability of the dissolved oxygen concentration.

[0079] Furthermore, this embodiment provides a dissolved oxygen concentration monitoring system, such as Figure 7 As shown, the dissolved oxygen concentration monitoring system includes a main control unit 400 and a dissolved oxygen concentration monitoring device as described above. Among them, the main control unit 400 uses an industrial all-in-one machine BPT-10B-P28B, which integrates a processor 410, a memory 420, a display 430 and a communication interface 440. Among them, the processor 410 is Intel Atom D2700; further, the display 430 is a 10.1-inch resistive touch screen, which is a color touch screen for displaying dissolved oxygen concentration, temperature, alarm, dissolved oxygen concentration curve, etc.; further, the memory 420 is a 128G solid state hard disk; further, the communication interface 440 includes 1 RS-485 interface and 1 USB interface, which respectively realize data transmission between the comprehensive acquisition unit 100 and the external system.

[0080] Furthermore, the main control unit 400 is connected to the integrated collection unit 100 of the dissolved oxygen concentration monitoring device to establish a communication connection with the integrated collection unit 100 to achieve remote control of the integrated collection unit 100 and obtain dissolved oxygen concentration information from the integrated collection unit 100 .

[0081] Further, the system also includes a power module 300; the power module 300 is connected to the main control unit 400 and the comprehensive acquisition unit 100 respectively, and is used to access an external power supply and supply power to the main control unit 400 and the comprehensive acquisition unit 100. Here, the power module 300 includes a filter 310 and a linear power supply 320, wherein the filter 310 uses a double-section universal power filter, and its function is to filter the power supply connected from the outside to prevent electromagnetic interference from affecting the measurement results. Further, the linear power supply 320 uses a dual-line linear power supply, and its function is to convert 220V AC into low-ripple +24V DC to power the various electrical components in the comprehensive acquisition unit 100 and the main control unit 400. The dissolved oxygen concentration monitoring system provided in the present application can accurately monitor the concentration of dissolved oxygen, and can intuitively display the monitoring results, and in terms of operation, it greatly improves the efficiency of monitoring the concentration of dissolved oxygen.

[0082] Those skilled in the art will appreciate that the accompanying drawings are only schematic diagrams of a preferred implementation scenario, and the modules or processes in the accompanying drawings are not necessarily necessary for implementing the present application. Those skilled in the art will appreciate that the modules in the devices in the implementation scenario can be distributed in the devices of the implementation scenario according to the description of the implementation scenario, or can be changed accordingly and located in one or more devices different from the present implementation scenario. The modules of the above-mentioned implementation scenario can be combined into one module, or can be further split into multiple submodules.

[0083] The above serial numbers of this application are only for description and do not represent the advantages and disadvantages of the implementation scenarios. The above disclosure is only a few specific implementation scenarios of this application, but this application is not limited to them, and any changes that can be thought of by technicians in this field should fall within the scope of protection of this application.

Claims

1. A dissolved oxygen concentration monitoring device for monitoring the dissolved oxygen concentration of an aqueous solution circulating in an electric power device, characterized in that: The device includes an integrated collection unit and at least one dissolved oxygen measurement unit; The dissolved oxygen measurement unit is used to generate a dissolved oxygen current signal based on the concentration of dissolved oxygen in the aqueous solution, and send the dissolved oxygen current signal to the comprehensive acquisition unit; The dissolved oxygen measuring unit is also used to collect temperature information of the dissolved oxygen measuring unit and send the temperature information to the comprehensive collection unit; The comprehensive acquisition unit is used to convert the dissolved oxygen current signal into a dissolved oxygen voltage signal, and calculate the concentration information of dissolved oxygen in the aqueous solution based on the temperature information and the dissolved oxygen voltage signal.

2. The device according to claim 1, characterized in that The comprehensive acquisition unit calculates the concentration information of dissolved oxygen in the aqueous solution based on the temperature information and the dissolved oxygen voltage signal, including: The comprehensive acquisition unit acquires a preset dissolved oxygen correction coefficient, and corrects the dissolved oxygen voltage signal based on the dissolved oxygen correction coefficient to obtain the corrected dissolved oxygen voltage signal; The oxygen partial pressure value is calculated based on the temperature information and the corrected dissolved oxygen voltage signal, and the concentration information is calculated based on the oxygen partial pressure value and the temperature information.

3. The device according to claim 1, characterized in that The dissolved oxygen measurement unit includes a circulation cell, a temperature sensor and a dissolved oxygen sensor; The circulation pool has a hollow inner cavity, and the hollow inner cavity is connected to a pipeline for conveying the aqueous solution, so that the aqueous solution can flow into the hollow inner cavity and flow out of the hollow inner cavity; The dissolved oxygen sensor is used to generate a dissolved oxygen current signal based on the concentration of dissolved oxygen in the aqueous solution in the hollow inner cavity, and send the dissolved oxygen current signal to the comprehensive acquisition unit; The temperature sensor is used to collect the temperature value of the dissolved oxygen sensor, and send the temperature value as the temperature information to the comprehensive collection unit.

4. The device according to claim 3, characterized in that The dissolved oxygen sensor comprises a sensor housing and a sensor electrode connected to the integrated collection unit, the sensor housing comprises a hollow chamber and a sensor housing opening communicating with the hollow chamber, and the sensor electrode is arranged in the hollow chamber; The circulation cell has a circulation cell shell, the hollow inner cavity is arranged in the circulation cell shell, and the circulation cell shell has a liquid inlet, a liquid outlet and a sensor docking interface; The sensor docking port is in communication with the sensor housing opening so that the hollow chamber is in communication with the hollow inner cavity; The liquid inlet is communicated with the pipeline so that the aqueous solution in the pipeline can flow into the hollow inner cavity, and the liquid outlet is communicated with the pipeline so that the aqueous solution in the hollow inner cavity can flow out to the pipeline.

5. The device according to claim 4, characterized in that The opening of the sensor housing is covered with a waterproof and breathable membrane, which is used to isolate the aqueous solution in the hollow inner cavity from the hollow chamber and allow the gas in the aqueous solution to flow into the hollow chamber; The sensor electrode comprises a working electrode and a counter electrode respectively connected to the integrated collection unit, and the hollow chamber is filled with an electrolyte; The comprehensive acquisition unit is used to output a working voltage to the counter electrode, so that the working electrode outputs the dissolved oxygen current signal.

6. The device according to claim 5, characterized in that The working electrode comprises a first electrode and a second electrode; The first electrode is arranged in a hollow column surrounded by the second electrode, a first end of the hollow column has an electrolyte flow port, and a second end of the hollow column extends out of the sensor housing; The first electrode is connected to the comprehensive acquisition unit and is used to send the dissolved oxygen current signal to the comprehensive acquisition unit.

7. The device according to claim 5, characterized in that The comprehensive acquisition unit includes a first conditioning circuit, a data acquisition circuit and a microprocessor; The first conditioning circuit is connected to the working electrode of the dissolved oxygen sensor, and is used to obtain the dissolved oxygen current signal from the working electrode and convert the dissolved oxygen current signal into the dissolved oxygen voltage signal; The data acquisition circuit is connected to the temperature sensor and the first conditioning circuit respectively, and is used to perform analog-to-digital conversion on the acquired dissolved oxygen voltage signal and the temperature information to obtain the dissolved oxygen voltage signal and the temperature information in the form of digital signals, and send the dissolved oxygen voltage signal and the temperature information in the form of digital signals to the microprocessor; The microprocessor is used to calculate the concentration information of dissolved oxygen in the aqueous solution based on the temperature information and the dissolved oxygen voltage signal.

8. The device according to claim 7, characterized in that The comprehensive acquisition unit also includes a communication circuit; The communication circuit is connected to the microprocessor, and the communication circuit is used to connect the microprocessor to a remote host computer to establish a communication connection between the host computer and the microprocessor.

9. The device according to claim 7, characterized in that The comprehensive acquisition unit also includes a driving circuit; The driving circuit is respectively connected to the microprocessor, the dissolved oxygen sensor and the temperature sensor; The microprocessor is also used to send a temperature acquisition signal to the drive circuit, so that the drive circuit sends a temperature drive current to the temperature sensor, so that the temperature sensor enters a working state; The microprocessor is also used to send a dissolved oxygen collection signal to the drive circuit, so that the drive circuit sends an electrode drive voltage to the dissolved oxygen sensor, so that the dissolved oxygen sensor enters a working state.

10. A dissolved oxygen concentration monitoring system, characterized in that: The dissolved oxygen concentration monitoring system comprises a main control unit and a dissolved oxygen concentration monitoring device as claimed in any one of claims 1 to 9; The main control unit is connected to the comprehensive acquisition unit of the dissolved oxygen concentration monitoring device, and is used to establish a communication connection with the comprehensive acquisition unit; The system also includes a power module; The power supply module is connected to the main control unit and the comprehensive acquisition unit respectively, and is used to access an external power supply and supply power to the main control unit and the comprehensive acquisition unit.

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