Coupling multi-electrode array corrosion on-line monitor and working method thereof

Abstract

A coupled multi-electrode array corrosion online monitoring instrument includes a controller electrically connected to multiple current measurement units and multiple voltage measurement units. Each voltage measurement unit is electrically connected to a reference electrode. Each electrode is connected to a corresponding current measurement unit and a corresponding voltage measurement unit via a first relay. The electrode switches between being electrically connected to the voltage measurement unit and the current measurement unit via the first relay. The operation method of the coupled multi-electrode array corrosion online monitoring instrument includes power-on, controller operation, and data uploading. In this embodiment, the controller simultaneously measures signals from each electrode through each current measurement unit, obtaining corrosion data at the same time, providing accurate research basis for the change process of micro-area corrosion. This not only meets the needs of pipeline corrosion status detection but also allows for flexible switching between pipeline and medium corrosion detection.

Description

Technical Field

[0001] This invention belongs to the field of online corrosion monitoring technology, and particularly relates to an online corrosion monitoring instrument with coupled multi-electrode array and its working method. Background Technology

[0002] CMAS primarily measures the corrosion current of each electrode in a coupled electrode array probe continuously. The local corrosion amount (i.e., corrosion depth), particularly the pitting corrosion state, is obtained by integrating the corrosion current over time. Secondly, CMAS can also measure the polarization potential of each electrode in the coupled electrode array probe to characterize the potential distribution and aid in the analysis of the corrosion state of each electrode. This has a certain role in the analysis of the corrosion distribution of dissimilar metal galvanic couples and is significant in both industrial field monitoring and laboratory analysis.

[0003] Currently used CMAS testing equipment has the following problems:

[0004] 1. The scanning measurement method is used to complete the signal measurement of multiple electrodes, that is, each electrode in the coupled electrode array probe is measured one by one. It takes 3 to 10 seconds to measure each current data. It takes several minutes to tens of minutes to complete the sequential measurement of all electrodes. It is impossible to obtain corrosion data at the same time, which is not conducive to the accurate study of the change process of micro-area corrosion.

[0005] 2. When measuring the polarization potential of a certain electrode, all other electrodes need to be suspended. When all electrodes need to be measured at once, the electrodes will be in a non-coupled state for a long time, which will seriously affect the surface state of the electrodes and is not conducive to the accuracy of subsequent measurements.

[0006] 3. The measurement conditions connected to the pipeline were not considered. In actual field monitoring, the corrosion status of the pipeline at the monitoring point could not be accurately obtained. Only the corrosivity of the medium around the probe could be obtained, which does not meet the requirements of corrosion measurement. Summary of the Invention

[0007] To address the shortcomings of related technologies, this invention provides a coupled multi-electrode array corrosion online monitoring instrument and its working method, which solves the problems of long measurement cycles, inability to accurately reflect micro-area corrosion changes, impact of a single measurement on subsequent polarization potential detection, and inability to obtain pipeline corrosion status in current CMAS detection equipment.

[0008] This invention provides an online corrosion monitoring instrument for coupled multi-electrode arrays, including a controller, which is electrically connected to multiple current measurement units and multiple voltage measurement units;

[0009] The voltage measurement units are all electrically connected to the reference electrode of the coupled electrode array probe, and the reference electrode is electrically connected to the second ground terminal;

[0010] Each electrode of the coupled electrode array probe is connected to a corresponding current measurement unit and a corresponding voltage measurement unit through a first relay. The first relay is a selection switch, and the electrode switches between being electrically connected to the voltage measurement unit and being electrically connected to the current measurement unit through the first relay.

[0011] The pipeline is electrically connected to the first grounding terminal via the second relay, and all current measuring units are electrically connected to the pipeline via the second relay.

[0012] The controller controls the connection of the first relay and the second relay;

[0013] The current measurement unit includes an I / V conversion unit, a low-pass filter, an analog-to-digital conversion unit, and a digital isolation unit connected in series. The digital isolation unit is electrically connected to the controller, and the I / V conversion unit is electrically connected to the second relay and the corresponding first relay. The voltage measurement unit includes a follower unit, a low-pass filter, an analog-to-digital conversion unit, and a digital isolation unit connected in series. The digital isolation unit is electrically connected to the controller, and the follower unit is electrically connected to the reference electrode and the corresponding first relay. The controller is electrically connected to a memory and a communication unit.

[0014] In some embodiments, a power supply module is further included, which includes a first isolated power supply, a second isolated power supply, and a third isolated power supply. The first isolated power supply supplies power to the second isolated power supply, the third isolated power supply, and the controller. The current measurement units are all connected to the second isolated power supply, and the voltage measurement units are all connected to the third isolated power supply.

[0015] In some embodiments, the controller controls connections to a second isolated power supply and a third isolated power supply.

[0016] In some of these embodiments, the controller is electrically connected to a satellite time synchronization unit.

[0017] A method for operating a coupled multi-electrode array corrosion online monitoring instrument, using the coupled multi-electrode array corrosion online monitoring instrument according to any one of claims 1 to 4, comprises the following steps:

[0018] ① Power on and read the working mode and measurement cycle from the memory;

[0019] ② The controller operates according to the working mode and measurement cycle to obtain measured and processed monitoring data;

[0020] ③ The controller sends the monitoring data to the memory for storage;

[0021] ④ The controller uploads the monitoring data stored in the memory to the host computer through the communication unit;

[0022] ⑤ Repeat steps ② through ④.

[0023] The host computer writes the working mode into the memory through the communication unit and the controller. The working modes include current synchronization measurement mode and polarization potential synchronization measurement mode.

[0024] When the controller operates in current synchronous measurement mode, select electrodes D1 to D2. n In the diagram, 'a' represents the first target electrode, where 'a' is less than or equal to 'n'. The controller controls the first target electrode D. f-1 ~D f-a The first relays connected to the circuit are all switched to electrical connection with the current measuring unit; the controller controls the corresponding multiple current measuring units to simultaneously measure the first target electrode D. f-1 ~D f-a Measurements were performed to obtain the first target electrode D. f-1 ~D f-a The measured current is then passed through a low-pass filter in the current measurement unit to the first target electrode D. f-1 ~D f-a The measured current is filtered to obtain the first target electrode D. f-1 ~D f-a The controller calculates the DC current of the first target electrode D during the measurement cycle. f-1 ~D f-a The average and maximum values ​​of the DC current are used to obtain the first target electrode D. f-1 ~D f-a The controller obtains the average current and maximum current of the first target electrode D during the measurement cycle. f-1 ~D f-a The controller sets the average corrosion current and maximum corrosion current of the electrode as follows: when the average current of the electrode is less than or equal to 0, the controller sets the average corrosion current of the electrode to 0; when the average current of the electrode is greater than 0, the controller sets the average current of the electrode to its average corrosion current. When the maximum current of the electrode is less than or equal to 0, the controller sets the maximum corrosion current of the electrode to 0; when the maximum current of the electrode is greater than 0, the controller sets the maximum current of the electrode to its maximum corrosion current. The controller will measure the first target electrode D within the measurement cycle. f-1 ~D f-a The average corrosion current and maximum corrosion current are stored as monitoring data in the memory;

[0025] When the controller operates in polarization potential synchronous measurement mode, electrodes D1 to D2 are selected. n In the diagram, b are the second target electrodes, where b is less than or equal to n. The controller controls the second target electrode D. s-1 ~D s-b All connected first relays are switched to electrical connection with the voltage measurement unit; after a set delay time T, the controller controls the corresponding multiple voltage measurement units to simultaneously measure the second target electrode D. s-1 ~Ds-b Measurements were performed to obtain the second target electrode D. s-1 ~D s-b The polarization potential; the controller will set the second target electrode D s-1 ~D s-b The polarization potential is stored in the memory as monitoring data.

[0026] In some embodiments, the controller simultaneously operates a current synchronization measurement mode and a polarization potential synchronization measurement mode, with the number of first target electrodes being a and the number of second target electrodes being b, where a+b≤n.

[0027] In some embodiments, the electrodes of the coupled electrode array probe are arranged in a matrix. From one side of the coupled electrode array probe to the other side, multiple electrodes in each row are sequentially set as the first target electrode or the second target electrode. The controller operates sequentially according to the working mode and obtains the monitoring data of multiple electrodes in each row in sequence.

[0028] In some embodiments, the controller summarizes and processes the monitoring data for one hour starting from the hour according to its built-in clock, obtains hourly summary data, and stores it in memory. The hourly summary data includes electrodes D1 to D2. n Average corrosion current per hour, electrode D1~D n Maximum corrosion current per hour, electrodes D1~D n Average polarization potential per hour, electrode D1~D n Most positive polarization potential and electrodes D1~D within one hour n The most negative polarization potential within one hour;

[0029] The controller establishes a communication connection with the host computer through the communication unit and runs the first data upload step;

[0030] First data upload: The controller determines whether the memory stores hourly summary data marked as not uploaded. If the result is yes, the controller uploads all hourly summary data marked as not uploaded to the host computer and marks the corresponding hourly summary data as uploaded. If the result is no, the controller runs the second data upload step.

[0031] Second data upload: The controller determines whether the memory stores monitoring data marked as not uploaded. If the result is yes, the controller uploads all monitoring data marked as not uploaded to the host computer and marks the corresponding monitoring data as uploaded.

[0032] In some embodiments, step ④ is further followed by an abnormal electrode determination step:

[0033] Abnormal electrode identification: Calculate electrodes D1 to D2n The first judgment coefficient X and the second judgment coefficient Y are used. If the first judgment coefficient X is greater than or equal to threshold A and the second judgment coefficient Y is greater than or equal to threshold B, then the electrode is marked as a first abnormal electrode, and the first abnormal electrode disconnection step is performed. Y = |I a -I b |,I a For the average current during the electrode measurement period, I b The average current over all electrode measurement cycles is the average value, and thresholds A and B are set manually.

[0034] First abnormal electrode disconnection: Switch the first relay corresponding to the first abnormal electrode to be electrically connected to the voltage measurement unit.

[0035] In some embodiments, the abnormal electrode determination step further includes calculating electrodes D1 to D2. n The third judgment coefficient Z is used. If the third judgment coefficient Z is greater than or equal to the threshold C, then the electrode is marked as the second abnormal electrode, and the second abnormal electrode disconnection step is performed, where Z = |V a -V b |,V a For the polarization potential during the electrode measurement period, V b The threshold C is the average value of the polarization potential over all electrode measurement cycles, and is set manually.

[0036] Second abnormal electrode cut-off: Maintain or switch the first relay corresponding to the second abnormal electrode to be electrically connected to the voltage measurement unit.

[0037] Based on the above technical solution, in this embodiment of the invention, the controller simultaneously measures the signals of each electrode through each current measurement unit to obtain corrosion data at the same moment, providing an accurate research basis for the change process of micro-area corrosion. When the second relay is closed, each current measurement unit is connected to the pipeline to measure the corrosion state of the pipeline at the detection point. After the second relay is opened, each current measurement unit is disconnected from the pipeline, retaining only the electrical connection between them through the first grounding terminal, switching to the detection of corrosion of the medium around the probe. This not only meets the needs of pipeline corrosion state detection but also allows for flexible switching between pipeline and medium corrosion detection. Through the electrical connection switching of the first relay, the required electrodes can be connected to the voltage measurement unit for polarization potential detection, while the remaining electrodes remain electrically connected to the pipeline, maintaining sufficient coupling and ensuring accurate polarization potential detection of subsequent electrodes. This solves the problems of current CMAS detection equipment, such as long measurement cycle, inability to accurately reflect micro-area corrosion changes, impact of a single measurement on subsequent polarization potential detection, and inability to accurately obtain the pipeline corrosion state. Attached Figure Description

[0038] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0039] Figure 1 This is a schematic diagram of the online corrosion monitoring instrument with coupled multi-electrode array according to the present invention;

[0040] Figure 2 This is a schematic diagram of the current measurement unit in the online corrosion monitoring instrument with coupled multi-electrode array of the present invention;

[0041] Figure 3 This is a schematic diagram of the voltage measurement unit in the online corrosion monitoring instrument with coupled multi-electrode array of the present invention;

[0042] Figure 4 This is a wiring diagram of the relay, current measurement unit, and voltage measurement unit in the online corrosion monitoring instrument for coupled multi-electrode arrays of the present invention;

[0043] In the picture:

[0044] 1. Controller; 21. Current measurement unit; 22. Voltage measurement unit; 3. Reference electrode; 4. Electrode; 51. First relay; 52. Second relay; 6. I / V conversion unit; 7. Low-pass filter; 8. Analog-to-digital conversion unit; 9. Digital isolation unit; 10. Follower unit; 11. First isolation power supply; 12. Second isolation power supply; 13. Third isolation power supply; 14. Memory; 15. Communication unit; 16. Satellite time synchronization unit; A. Pipe; 101. First grounding terminal; 102. Second grounding terminal. Detailed Implementation

[0045] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0046] In the description of this invention, it should be understood that the terms "center", "lateral", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0047] The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.

[0048] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0049] like Figure 1 As shown, in an illustrative embodiment of the online corrosion monitoring instrument for coupled multi-electrode arrays of the present invention, the online corrosion monitoring instrument for coupled multi-electrode arrays includes a controller 1, which is electrically connected to multiple current measurement units 21 and multiple voltage measurement units 22.

[0050] like Figure 4 As shown, the voltage measurement unit 22 is electrically connected to the reference electrode 3 of the coupling electrode array probe, and the reference electrode 3 is electrically connected to the second ground terminal 102.

[0051] Each electrode 4 of the coupled electrode array probe is connected to a corresponding current measurement unit 21 and a corresponding voltage measurement unit 22 through a first relay 51. The first relay 51 is a selection switch, namely a single-pole double-throw relay. The electrode 4 switches between being electrically connected to the voltage measurement unit 22 and being electrically connected to the current measurement unit 21 through the first relay 51.

[0052] Pipe A is electrically connected to the first grounding terminal 101 via the second relay 52. ​​All current measuring units 21 are electrically connected to pipe A via the second relay 52, so that all current measuring units 21 are electrically connected to the first grounding terminal 101.

[0053] Controller 1 controls the connection of the first relay 51 and the second relay 52.

[0054] Among them, such as Figures 2 to 3As shown, the current measurement unit 21 includes an I / V conversion unit 6, a low-pass filter 7, an analog-to-digital conversion unit 8, and a digital isolation unit 9 connected in series. The digital isolation unit 9 is electrically connected to the controller 1, and the I / V conversion unit 6 is electrically connected to the second relay 52 and the corresponding first relay 51. The voltage measurement unit 22 includes a follower unit 10, a low-pass filter 7, an analog-to-digital conversion unit 8, and a digital isolation unit 9 connected in series. The digital isolation unit 9 is electrically connected to the controller 1, and the follower unit 10 is electrically connected to the reference electrode 3 and the corresponding first relay 51. The controller 1 is electrically connected to a memory 14 and a communication unit 15.

[0055] The working method of the above-mentioned coupled multi-electrode array corrosion online monitoring instrument includes the following steps:

[0056] ① Power on the device and turn on the monitor. The controller 1 of the monitor reads the working mode and measurement cycle from the memory 14.

[0057] ② Controller 1 operates according to the read working mode and measurement cycle to obtain the measured and processed monitoring data;

[0058] ③ The controller 1 sends the monitoring data to the memory 14 for storage;

[0059] ④ When the controller 1 establishes a communication connection with the host computer through the communication unit 15, it uploads the monitoring data stored in the memory 14 to the host computer.

[0060] ⑤ Repeat steps ② through ④.

[0061] After the controller 1 of the monitor establishes a communication connection with the host computer, the host computer can transmit the working mode and / or measurement cycle to the monitor's memory. If the working mode and measurement cycle are already stored in the memory, the working mode and / or measurement cycle transmitted from the host computer will overwrite the original working mode and / or measurement cycle in the memory.

[0062] The operating modes include synchronous current measurement mode and synchronous polarization potential measurement mode.

[0063] In step ②, when the controller operates in the current synchronization measurement mode, electrodes D1 to D2 are selected. n In the diagram, 'a' represents the first target electrode, where 'a' is less than or equal to 'n'. The controller controls the first target electrode D. f-1 ~D f-a The first relays connected to the circuit are switched to electrical connection with the current measurement unit.

[0064] The controller controls multiple current measurement units corresponding to the first target electrode, simultaneously measuring the first target electrode D within the measurement cycle. f-1 ~D f-a Measurements were performed to obtain the first target electrode D.f-1 ~D f-a The measured current is then passed through a low-pass filter in the current measurement unit to the first target electrode D. f-1 ~D f-a The measured current is filtered to obtain the first target electrode D. f-1 ~D f-a DC current.

[0065] The controller calculates the first target electrode D within the measurement cycle. f-1 ~D f-a The average and maximum values ​​of the DC current are used to obtain the first target electrode D. f-1 ~D f-a The average current and the maximum current.

[0066] The controller is based on the first target electrode D f-1 ~D f-a The average current and maximum current of the first target electrode D during the measurement period were obtained respectively. f-1 ~D f-a The controller sets the average corrosion current and maximum corrosion current of the electrode. If the average current of the electrode is less than or equal to 0, the controller sets the average corrosion current of the electrode to 0; if the average current of the electrode is greater than 0, the controller sets the average current of the electrode to the average corrosion current of the electrode. If the maximum current of the electrode is less than or equal to 0, the controller sets the maximum corrosion current of the electrode to 0; if the maximum current of the electrode is greater than 0, the controller sets the maximum current of the electrode to its maximum corrosion current.

[0067] The controller will measure the first target electrode D within the measurement cycle. f-1 ~D f-a The average corrosion current and maximum corrosion current are stored as monitoring data in the memory. The maximum corrosion current is the first target electrode D. f-1 ~D f-a It is the largest of the average corrosion currents.

[0068] The coupled electrode array probe has n electrodes. When the controller operates in the current synchronous measurement mode, some electrodes can be selected as the first target electrode, in which case a is less than n; alternatively, all electrodes can be selected as the first target electrode, in which case a equals n. The first relay K... 1-1 ~K 1-n Switch all devices to the state of being electrically connected to the current measurement unit 21.

[0069] Additionally, when controller 1 is operating in current synchronous measurement mode, if the controller controls the second relay K2 to close, current measurement units A1 to A2 will... nThe second relay K2 is electrically connected to pipe A. At this time, the current measuring unit is electrically connected to the electrode and pipe A respectively. The monitoring data obtained is the average corrosion current and the maximum corrosion current of pipe A at the detection point where the coupled electrode array probe is located. If the controller controls the second relay K2 to disconnect, the current measuring units A1 to A2... n Both are electrically connected to the first grounding terminal G1. At this time, the current measuring unit is electrically connected to the electrode and the first grounding terminal G1 respectively. The monitoring data obtained at this time are the average corrosion current and the maximum corrosion current of the medium around the coupled electrode array probe.

[0070] In step ②, when the controller operates in the polarization potential synchronous measurement mode, electrodes D1 to D2 are selected. n In the diagram, b are the second target electrodes, where b is less than or equal to n. The controller controls the second target electrode D. s-1 ~D s-b The first relays connected to the circuit are switched to electrical connection with the voltage measurement unit.

[0071] After a set delay time T, the controller controls the second target electrode D. s-1 ~D s-b The corresponding multiple voltage measurement units simultaneously measure the second target electrode D. s-1 ~D s-b Measurements were performed to obtain the second target electrode D. s-1 ~D s-b The polarization potential.

[0072] The controller will target the second electrode D s-1 ~D s-b The polarization potential is stored in the memory as monitoring data.

[0073] After the polarization potential synchronous measurement mode is completed, the first relay corresponding to the second target electrode is immediately switched to electrical connection with the current measurement unit 21, that is, the coupling state of the electrode is restored, reducing the impact on the electrode.

[0074] When the first relay 51 is electrically connected to the current measuring unit 21 and the second relay 52 is closed, the electrode 4 is electrically connected to the pipe A through the current measuring unit 21, thus enabling the electrode to be in a coupled state, i.e., a polarized state. Since the electrode 4 needs to be in a coupled state to obtain an accurate polarization potential, when measuring the polarization potential of an electrode 4, the first relay 51 switches to electrical connection with the voltage measuring unit 21, which will disconnect the electrical connection between the electrode 4 and the pipe A, making the electrode A in a decoupled state. To detect the polarization potential of the electrode 4 again, the first relay 51 needs to be switched back to electrical connection with the current measuring unit 21 to restore the electrical connection between the electrode 4 and the pipe A, and this connection needs to be maintained for a period of time to allow the electrode 4 to return to its normal polarization state.

[0075] The current of the first target electrode is continuously and in real time during a measurement cycle. Based on the current measured in that cycle, the average current of the electrode is obtained through filtering, conversion, and averaging. The polarization potential of the second target electrode is measured only once per measurement cycle, ensuring that the second target electrode is in a coupled state and the measured polarization potential is accurate. After the polarization potential measurement is completed, the first relay is immediately switched to its electrical connection with the current measurement unit, reducing the duration of decoupling of the second target electrode and minimizing the impact of decoupling on the electrode.

[0076] The number of electrodes in the coupled electrode array probe is n. When the controller runs the polarization potential synchronous measurement mode, some electrodes can be selected as the second target electrode, in which case b is less than n; or all electrodes can be selected as the second target electrode, in which case b is equal to n.

[0077] In the above illustrative embodiments, the controller of the coupled multi-electrode array corrosion online monitoring instrument simultaneously measures some or more electrodes through multiple current measurement units to obtain corrosion data of multiple or all electrodes at the same time. The controller can also simultaneously measure some or all electrodes through multiple voltage measurement units to obtain the polarization potential of multiple or all electrodes at the same time, providing accurate research basis for the micro-area corrosion change process. Through the electrical connection switching of the first relay, the required electrodes can be connected to the voltage measurement unit for polarization potential detection, while the remaining electrodes remain electrically connected to the pipeline, maintaining a sufficient coupling state, enabling subsequent measurement of other electrodes. When performing polarization potential and corrosion current detection, the measured polarization potential and corrosion current are accurate. When the second relay is closed, each current measuring unit is connected to the pipeline, thereby measuring the corrosion state of the pipeline at the detection point. After the second relay is closed, each current measuring unit is electrically connected to the grounding terminal, switching to the detection of corrosion of the medium around the probe. This not only meets the needs of pipeline corrosion state detection, but also allows for flexible switching between pipeline and medium corrosion detection. It solves the problems of current CMAS detection equipment, such as long measurement cycle, inability to accurately reflect micro-area corrosion changes, impact of a single measurement on subsequent polarization potential and corrosion current detection, and inability to obtain the pipeline corrosion state.

[0078] When the first relay 51 electrically connects electrode 4 to the current measuring unit 21, and the second relay 52 is closed, the I / V conversion unit 6 of the current measuring unit 21 is electrically connected to electrode 4 and pipe A, respectively. When the first relay 51 electrically connects electrode 4 to the current measuring unit 21, and the second relay 52 is open, the I / V conversion unit 6 is electrically connected to the first grounding terminal 101 and electrode 4, respectively. The I / V conversion unit 6 collects the corrosion current of the pipe or the corrosion current of the medium by electrically connecting pipe A and electrode 4, or electrically connecting electrode 4 and the first grounding terminal 101.

[0079] The I / V conversion unit 6 converts the collected corrosion current into a voltage signal. After the voltage signal is filtered by the low-pass filter 7, it is converted into a digital signal by the analog-to-digital conversion unit 8 and transmitted to the controller 1 through the digital isolation unit 9, ensuring that the measurement data collected by the controller 1 is accurate.

[0080] When the first relay 51 electrically connects electrode 4 to voltage measurement unit 22, voltage measurement unit 22 acquires polarization potential through electrode 4 and reference electrode 3. Follower unit 10 increases impedance, thereby improving the accuracy of the acquired potential difference. The acquired potential difference is filtered by low-pass filter 7 and then converted into a digital signal by analog-to-digital conversion unit 8. It is then transmitted to controller 1 through digital isolation unit 9 to ensure that the measurement data acquired by controller 1 is accurate.

[0081] In some embodiments, the online corrosion monitoring instrument for coupled multi-electrode arrays further includes a power supply module, which includes a first isolation power supply 11, a second isolation power supply 12, and a third isolation power supply 13. The first isolation power supply 11 supplies power to the second isolation power supply 12, the third isolation power supply 13, and the controller 1. The current measurement units 21 are all connected to the second isolation power supply 12 for power supply, and the voltage measurement units 22 are all connected to the third isolation power supply 13 for power supply.

[0082] Current measurement units A1~A n Powered by a second isolation power supply 12, voltage measurement units V1 to V n The device is further simplified by being powered by a third isolated power supply 13.

[0083] In some embodiments, the controller 1 controls the connection of the second isolated power supply 12 and the third isolated power supply 13 to control the power supply of the current measurement unit 21 and the voltage measurement unit 22, ensuring stable power supply and accurate data acquisition. When measurement is not required, the second isolated power supply 12 and the third isolated power supply 13 can be turned off to reduce device power consumption. To avoid interference, both the second isolated power supply 12 and the third isolated power supply 13 are connected to the controller 1 through isolators.

[0084] In some embodiments, the controller 1 is electrically connected to a satellite time synchronization unit 16. The satellite time synchronization unit 16 can calibrate the clock set in the monitor, so that multiple monitors can synchronously measure corrosion current or polarization potential according to the same clock, thereby enabling synchronous measurement and analysis of corrosion changes over a large area and long distance.

[0085] In some embodiments, in step ②, the controller simultaneously operates the current synchronization measurement mode and the polarization potential synchronization measurement mode, that is, the controller operates two working modes simultaneously. When the controller operates two working modes simultaneously, the first relay of a portion of the electrodes switches to electrical connection with the current measurement unit to detect corrosion current. The number of this portion of electrodes is 'a', that is, the number of the first target electrodes is 'a'. The first relay of another portion of the electrodes switches to electrical connection with the voltage measurement unit to detect polarization potential. The number of this portion of electrodes is 'b', that is, the number of the second target electrodes is 'b'. a+b≤n, all electrodes can be divided into two groups, one group for detecting corrosion current and the other group for detecting polarization potential; alternatively, a portion of all electrodes can be divided into two groups, one group for detecting corrosion current and the other group for detecting polarization potential.

[0086] The simultaneous detection of corrosion current and polarization potential not only improves the efficiency of data measurement, but also maximizes the accuracy of the measurement by measuring both types of data at the same time. Furthermore, it provides two dimensions of data support for the corrosion state, enabling a more accurate and comprehensive study of the changes in micro-area corrosion.

[0087] In some embodiments, the electrodes of the coupled electrode array probe are arranged in a matrix. From one side of the coupled electrode array probe to the other side, multiple electrodes in each row are sequentially set as the first target electrode or the second target electrode. The controller operates sequentially according to the working mode and obtains the monitoring data of multiple electrodes in each row in sequence.

[0088] In step ②, the controller operates in current synchronization measurement mode. The controller selects multiple electrodes in the first row from one side of the probe as the first target electrodes, obtaining the average corrosion current and maximum corrosion current of the first row of electrodes within the measurement period. The controller then selects multiple electrodes in the second row from the other side of the probe as the first target electrodes, obtaining the average corrosion current and maximum corrosion current of the second row of electrodes within the measurement period. Following this method, from one side of the probe to the other, each row of electrodes is sequentially selected as the first target electrode, and the corresponding average corrosion current and maximum corrosion current are obtained, thereby achieving line-by-line scanning of the corrosion current.

[0089] In step ②, the controller operates in polarization potential synchronous measurement mode. The controller selects multiple electrodes from the first row on one side of the probe as the second target electrodes, obtaining the polarization potentials of the first row of electrodes within the measurement period. Similarly, the controller selects multiple electrodes from the second row on the other side of the probe as the second target electrodes, obtaining the polarization potentials of the second row of electrodes within the measurement period. Following this method, from one side of the probe to the other, the electrodes in each row are sequentially selected as the second target electrodes, and the corresponding polarization potentials are obtained, thus achieving line-by-line scanning of the polarization potentials.

[0090] When the controller operates in the working mode, it can perform line-by-line scanning of corrosion current or polarization potential by measuring the electrodes row by row, increasing the diversity of collected data, improving the flexibility of the monitor, and meeting the needs of more corrosion state analysis.

[0091] In some embodiments, the controller has a built-in clock that aggregates and processes monitoring data for the hour starting at the top of the hour to obtain hourly summary data. More specifically, the controller aggregates and processes all monitoring data from the previous hour when the clock reaches the top of the hour, based on the current clock position, to obtain hourly summary data for the hour corresponding to the previous top of the hour.

[0092] Hourly summary data includes electrodes D1 to D n Average corrosion current per hour, electrode D1~D n Maximum corrosion current per hour, electrodes D1~D n Average polarization potential per hour, electrode D1~D n Most positive polarization potential and electrodes D1~D within one hour n The most negative polarization potential within one hour.

[0093] The one-hour average corrosion current of an electrode is the average of all average corrosion currents obtained by the electrode within one hour starting at the hour; the one-hour maximum corrosion current of an electrode is the largest of all maximum corrosion currents obtained within one hour starting at the hour; the one-hour average polarization potential of an electrode is the average of all polarization potentials obtained by the electrode within one hour starting at the hour; the one-hour most positive polarization potential of an electrode is the maximum value of all polarization potentials obtained by the electrode within one hour starting at the hour; the one-hour most negative polarization potential of an electrode is the minimum value of all polarization potentials obtained by the electrode within one hour starting at the hour.

[0094] Since hourly summary data can reflect the corrosion status throughout the entire hour, it is more representative in corrosion analysis and has a high level of importance. The controller stores the hourly summary data in memory to prevent the loss of important data.

[0095] The controller establishes a communication connection with the host computer through the communication unit and runs the first data upload step.

[0096] First data upload: The controller determines whether the memory stores hourly summary data marked as not uploaded. If the result is yes, the controller uploads all hourly summary data marked as not uploaded to the host computer and marks the corresponding hourly summary data as uploaded. If the result is no, the controller runs the second data upload step.

[0097] Second data upload: The controller determines whether the memory stores monitoring data marked as not uploaded. If the result is yes, the controller uploads all monitoring data marked as not uploaded to the host computer and marks the corresponding monitoring data as uploaded.

[0098] Because the monitoring instrument is subject to various factors during long-term monitoring in industrial fields, the communication between the instrument's controller and the host computer may be interrupted. When communication is interrupted, all data acquired by the monitoring instrument is stored in its memory.

[0099] Both hourly summary data and monitoring data have a marked status of not uploaded or uploaded. The marked status confirms whether the data stored in the memory has been successfully uploaded to the host computer.

[0100] Based on the above data upload mechanism, when the controller establishes a communication connection with the host computer, or more specifically, when the communication connection is interrupted and the controller resumes communication with the host computer, it prioritizes uploading the hourly summary data that has not yet been uploaded to the host computer, followed by the monitoring data that has not yet been uploaded. This ensures that more important data is uploaded to the host computer first, thereby maximizing the reception of hourly summary data by the host computer even when the communication connection is unstable, and thus providing sufficient data support for subsequent corrosion status analysis.

[0101] In some embodiments, after step ④, an abnormal electrode determination step is further included:

[0102] Abnormal electrode identification: Calculate electrodes D1 to D2 n The first judgment coefficient X and the second judgment coefficient Y are used. If the first judgment coefficient X is greater than or equal to threshold A and the second judgment coefficient Y is greater than or equal to threshold B, then the electrode is marked as a first abnormal electrode, and the first abnormal electrode disconnection step is performed. Y = |I a -I b |,I a For the average current during the electrode measurement period, I bThe average value of the average current over all electrode measurement cycles is given. Threshold A and threshold B are set manually. Threshold A has a range of 2 or higher, and threshold B has a range of one-thousandth of the current measurement unit range corresponding to the current electrode.

[0103] First abnormal electrode disconnection: Switch the first relay corresponding to the first abnormal electrode to be electrically connected to the voltage measurement unit.

[0104] If the first judgment coefficient X is greater than or equal to the threshold A, it means that the average current measured by the current electrode within the measurement period is more than twice as high as the average current of all electrodes within the measurement period. If the second judgment coefficient Y is greater than or equal to the threshold B, it means that the difference between the average current measured by the current electrode within the measurement period and the average current of all electrodes within the measurement period exceeds one-thousandth. Therefore, it is determined that the current measured by the current electrode has a significant difference compared with the current measured by other electrodes, and the electrode is judged to be the first abnormal electrode, that is, the electrode with abnormal current measurement.

[0105] After identifying the electrode with abnormal current measurement, the first relay disconnects its electrical connection with the current measurement unit and switches to electrical connection with its voltage measurement unit, maintaining this state. This cuts off the coupling between the electrode and other electrodes, preventing the abnormal electrode from affecting other electrodes.

[0106] In some embodiments, the abnormal electrode determination step further includes calculating electrodes D1 to D2. n The third judgment coefficient Z is used. If the third judgment coefficient Z is greater than or equal to the threshold C, then the electrode is marked as the second abnormal electrode, and the second abnormal electrode disconnection step is performed, where Z = |V a -V b |,V a For the polarization potential during the electrode measurement period, V b The threshold C is the average polarization potential over all electrode measurement cycles. The threshold C is manually set and ranges from 0 to 1. <C<200mV。

[0107] Second abnormal electrode cut-off: The first relay corresponding to the second abnormal electrode is kept in or switched to be electrically connected to the voltage measurement unit, thereby cutting off the coupling of the electrode with other electrodes and preventing the abnormal electrode from affecting other electrodes.

[0108] If the third judgment coefficient Z is greater than or equal to the threshold C, it means that the difference between the polarization potential measured by the current electrode in the measurement cycle and the average value of the polarization potential of all electrodes in the measurement cycle exceeds the reasonable range. Therefore, it is determined that the polarization potential measured by the current electrode has an unreasonable difference compared with the polarization potential measured by other electrodes, and the electrode is judged to be the second abnormal electrode, that is, the electrode with abnormal polarization potential measurement.

[0109] After identifying an electrode with abnormal current measurement, the first relay switches to or maintains electrical connection with the voltage measurement unit and does not revert to its connection with the current measurement unit after completing the polarization potential measurement, thereby cutting off the coupling between the electrode and other electrodes and avoiding the influence of the abnormal electrode on other electrodes.

[0110] The presence of electrode abnormalities is determined by measuring both current and polarization potential, and the corresponding measurements are then cut off to ensure the accuracy of the measured data to the greatest extent possible.

[0111] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0112] The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of the present invention or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the technical solutions claimed in the present invention.

Claims

1. A coupled multi-electrode array corrosion online monitoring instrument, characterized in that, Includes a controller, which is electrically connected to multiple current measurement units and multiple voltage measurement units; The voltage measurement units are all electrically connected to the reference electrode of the coupling electrode array probe, and the reference electrode is electrically connected to the second ground terminal; Each electrode of the coupled electrode array probe is connected to a corresponding current measurement unit and a corresponding voltage measurement unit through a first relay. The first relay is a selection switch, and the electrodes of the coupled electrode array probe are switched between being electrically connected to the voltage measurement unit and being electrically connected to the current measurement unit through the first relay. The pipeline is electrically connected to the first grounding terminal via a second relay, and all current measuring units are electrically connected to the pipeline via the second relay. The controller controls the connection of the first relay and the second relay; The current measurement unit includes an I / V conversion unit, a low-pass filter, an analog-to-digital converter, and a digital isolation unit connected in series. The digital isolation unit is electrically connected to the controller, and the I / V conversion unit is electrically connected to the second relay and the corresponding first relay. The voltage measurement unit includes a follower unit, a low-pass filter, an analog-to-digital converter, and a digital isolation unit connected in series. The digital isolation unit is electrically connected to the controller, and the follower unit is electrically connected to the reference electrode and the corresponding first relay. The controller is electrically connected to a memory and a communication unit.

2. The online corrosion monitoring instrument for coupled multi-electrode arrays according to claim 1, characterized in that, The system further includes a power supply module, which comprises a first isolated power supply, a second isolated power supply, and a third isolated power supply. The first isolated power supply powers the second isolated power supply, the third isolated power supply, and the controller. The current measurement units are all connected to the second isolated power supply, and the voltage measurement units are all connected to the third isolated power supply.

3. The online corrosion monitoring instrument for coupled multi-electrode arrays according to claim 2, characterized in that, The controller controls the connection to the second isolated power supply and the third isolated power supply.

4. The online corrosion monitoring instrument for coupled multi-electrode arrays according to claim 1, characterized in that, The controller is electrically connected to a satellite time synchronization unit.

5. A method for operating a coupled multi-electrode array corrosion online monitoring instrument, employing the coupled multi-electrode array corrosion online monitoring instrument as described in any one of claims 1 to 4, characterized in that, The steps are as follows: ① Power on and read the working mode and measurement cycle from the memory; ② The controller operates according to the working mode and measurement cycle to obtain measured and processed monitoring data; ③ The controller sends the monitoring data to the memory for storage; ④ The controller uploads the monitoring data stored in the memory to the host computer through the communication unit; ⑤ Repeat steps ② through ④. The host computer writes the working mode into the memory through the communication unit and the controller. The working modes include current synchronization measurement mode and polarization potential synchronization measurement mode. When the controller operates in synchronous current measurement mode, select the electrode. ~ In the diagram, 'a' represents the first target electrode, where 'a' is less than or equal to 'n'. The controller controls the first target electrode. ~ The first relays connected to the circuit are all switched to electrical connection with the current measuring unit; the controller controls the corresponding multiple current measuring units to simultaneously measure the first target electrode. ~ Measurements were performed to obtain the first target electrode. ~ The measured current is then passed through a low-pass filter in the current measurement unit to the first target electrode. ~ The measured current is filtered to obtain the first target electrode. ~ The controller calculates the DC current of the first target electrode within the measurement cycle. ~ The average and maximum values ​​of the DC current are used to obtain the first target electrode. ~ The average current and maximum current; the controller obtains the first target electrode during the measurement cycle. ~ The controller sets the average corrosion current and maximum corrosion current of the electrode as follows: when the average current of the electrode is less than or equal to 0, the controller sets the average corrosion current of the electrode to 0; when the average current of the electrode is greater than 0, the controller sets the average current of the electrode to its average corrosion current. When the maximum current of the electrode is less than or equal to 0, the controller sets the maximum corrosion current of the electrode to 0; when the maximum current of the electrode is greater than 0, the controller sets the maximum current of the electrode to its maximum corrosion current. The controller will then measure the first target electrode within the measurement cycle. ~ The average corrosion current and maximum corrosion current are stored as monitoring data in the memory; When the controller operates in polarization potential synchronous measurement mode, select the electrode. ~ In the diagram, b are the second target electrodes, where b is less than or equal to n. The controller controls the second target electrodes. ~ The first relay connected to the circuit is switched to electrical connection with the voltage measurement unit; delay setting time. Subsequently, the controller controls multiple corresponding voltage measurement units to simultaneously measure the second target electrode. ~ Measurements were performed to obtain the second target electrode. ~ The polarization potential; the controller will set the second target electrode ~ The polarization potential is stored in the memory as monitoring data.

6. The working method of the online corrosion monitoring instrument with coupled multi-electrode array according to claim 5, characterized in that, The controller operates simultaneously in current synchronization measurement mode and polarization potential synchronization measurement mode. The number of the first target electrodes is a, the number of the second target electrodes is b, and a+b≤n.

7. The working method of the online corrosion monitoring instrument with coupled multi-electrode array according to claim 5, characterized in that, The electrodes of the coupled electrode array probe are arranged in a matrix. From one side of the coupled electrode array probe to the other side, multiple electrodes in each row are set as the first target electrode or the second target electrode. The controller operates in sequence according to the working mode and obtains the monitoring data of multiple electrodes in each row in sequence.

8. The working method of the online corrosion monitoring instrument with coupled multi-electrode array according to claim 5, characterized in that, The controller aggregates and processes monitoring data for one hour starting from the hour, based on its built-in clock, to obtain hourly summary data, which is then stored in memory. The hourly summary data includes electrode data. ~ Average corrosion current per hour, electrode ~ Maximum corrosion current and electrode within one hour ~ Average polarization potential and electrode within one hour ~ Most positive polarization potential and electrode within one hour ~ The most negative polarization potential within one hour; The controller establishes a communication connection with the host computer through the communication unit and runs the first data upload step; First data upload: The controller determines whether the memory stores hourly summary data marked as not uploaded. If the result is yes, the controller uploads all hourly summary data marked as not uploaded to the host computer and marks the corresponding hourly summary data as uploaded. If the judgment result is negative, the controller will proceed with the second data upload step. Second data upload: The controller determines whether the memory stores monitoring data marked as not uploaded. If the result is yes, the controller uploads all monitoring data marked as not uploaded to the host computer and marks the corresponding monitoring data as uploaded.

9. The working method of the online corrosion monitoring instrument with coupled multi-electrode array according to claim 5, characterized in that, Step ④ is followed by an abnormal electrode detection step: Abnormal electrode identification: Calculation electrode ~ The first judgment coefficient X and the second judgment coefficient Y are used. If the first judgment coefficient X is greater than or equal to threshold A and the second judgment coefficient Y is greater than or equal to threshold B, then the electrode is marked as a first abnormal electrode, and the first abnormal electrode disconnection step is performed. Where X = Y= , The average current during the electrode measurement period, The average current over all electrode measurement cycles is the average value, and thresholds A and B are set manually. First abnormal electrode disconnection: Switch the first relay corresponding to the first abnormal electrode to be electrically connected to the voltage measurement unit.

10. The working method of the online corrosion monitoring instrument with coupled multi-electrode array according to claim 9, characterized in that, The abnormal electrode determination step further includes calculating the electrode. ~ The third judgment coefficient Z is used. If the third judgment coefficient Z is greater than or equal to the threshold C, then the electrode is marked as the second abnormal electrode, and the second abnormal electrode disconnection step is performed, where Z = , The polarization potential during the electrode measurement cycle. The threshold C is the average value of the polarization potential over all electrode measurement cycles, and is set manually. Second abnormal electrode cut-off: Maintain or switch the first relay corresponding to the second abnormal electrode to be electrically connected to the voltage measurement unit.

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