Method and system for monitoring voltage-sharing electrode of cooling water pipe in real time

Abstract

The invention provides a method and a system for monitoring a voltage-sharing electrode of a cooling water pipe in real time. The method comprises the following steps: monitoring leakage current flowing through a voltage-sharing electrode of a main cooling water pipe of the converter valve, cooling water conductivity, direct-current electrode bus voltage of the converter valve and a converter valve unlocking signal in real time; calculating a leakage current theoretical value of a voltage-sharing electrode of a main cooling water pipe of the converter valve according to the cooling water conductivity, the direct-current electrode bus voltage of the converter valve and the converter valve unlocking signal, and comparing the leakage current theoretical value with the leakage current monitored in real time; and determining the use performance of the voltage-sharing electrode of the main cooling water pipe of the converter valve according to the comparison result and the converter valve unlocking signal. According to the method, a traditional performance evaluation method of disassembling the voltage-sharing electrode to check the scaling degree is replaced, performance evaluation is more accurate and timely, the workload of voltage-sharing electrode maintenance is greatly reduced, a maintenance strategy of the voltage-sharing electrode can be formulated in a targeted mode on the basis, and lean maintenance of the voltage-sharing electrode is achieved.

Description

Technical Field

[0001] This application relates to the field of online monitoring technology for converter valves, and more specifically, to a method and system for real-time monitoring of the equalizing electrode of a cooling water pipe. Background Technology

[0002] The converter valve is a core component of high-voltage direct current (HVDC) transmission technology, and its reliable operation is crucial for the safe operation of the system. The converter valve has an internal cooling water circuit that removes the heat generated during operation through circulating water cooling. Cooling water enters and exits the converter valve through the main cooling water pipe. The main cooling water pipe is typically made of PVDF insulation material, and its two ends are connected to the valve cooling system and the metal water pipe inside the converter valve, respectively. Voltage equalizing electrodes are placed at both ends of the PVDF water pipe to introduce and remove leakage current from the cooling water, preventing current from entering the metal water pipe flange through the cooling water, causing corrosion of the sealing ring and metal water pipe, and leading to leakage problems over long-term operation.

[0003] Based on operational experience with high-pressure converter valves, the following common problems exist with the equalizing electrodes in the main cooling water pipe of the converter valve:

[0004] (1) Although there are equalizing electrodes in the main cooling water pipe, it is still impossible to completely avoid slight corrosion of the radiator and metal water pipe (most of the leakage current enters the water electrode, and a very small amount of current flows into the metal water pipe). The ions generated by corrosion will be deposited at the high-pressure side electrode of the PVDF water pipe, causing scale to form on the electrode.

[0005] (2) The design of the equalizing electrode structure is unreasonable, and the electrode will break after long-term operation.

[0006] (3) The corrosion resistance of the equalizing electrode material is insufficient, and long-term operation will cause serious electrode corrosion.

[0007] (4) Problems such as unreasonable design of the equalizing electrode structure, loose connection of the equipotential line, and detachment can cause the equalizing electrode to discharge during operation.

[0008] All of the above issues can affect the reliable operation of the converter valve, so it is necessary to monitor the status of the equalizing electrode properly to avoid problems.

[0009] Currently, converter valve maintenance involves periodic spot checks and descaling of the equalizing electrodes, typically conducted annually for one valve tower. However, this periodic maintenance method for the equalizing electrodes requires draining water from the converter valve, which is labor-intensive and may pose a risk of leakage.

[0010] The patent "Evaluation Method and System for Equalizing Capability of Equalizing Electrode in Converter Valve Internal Cooling System" proposes to evaluate the performance of equalizing electrode by leakage current, establish an equivalent circuit model of converter valve internal cooling system, calculate the leakage current value of equalizing electrode after different operating times, and predict the failure time of equalizing electrode. However, its accuracy depends on the equivalent circuit model, and the prediction results are greatly affected by various factors.

[0011] The patent "A Method and System for Measuring and Determining the Surface Impedance of a Pressure Equalizing Electrode" proposes to determine whether the electrode is scaled by comparing the measured impedance values ​​and standard values ​​of the pressure equalizing electrodes at both ends of the valve section. The patent "A Chengdu In-situ Optical Detection Device and Method for Scale on Pressure Equalizing Electrodes" proposes to obtain images of scale on the pressure equalizing electrodes through optical detection and to obtain electrode scale data by using image recognition algorithms. However, both of the above patents are offline detection methods, which still require checking each electrode during maintenance. Moreover, the detection impedance and scale thickness cannot be directly equivalent to the performance of the electrode.

[0012] The patent "An Online Monitoring System for Scaling of Equalizing Electrode of Converter Valve" proposes to monitor the corrosion and scaling of equalizing electrode of converter valve online by installing a monitoring terminal based on the principle of light reflection on the valve's cold water pipe. However, it uses the principle of light reflection to monitor the shape of the electrode installed in a non-transparent water pipe, which cannot be directly equivalent to the performance of the electrode.

[0013] The patent "An Online Monitoring Device for Electrode Corrosion and Deposition" proposes to monitor the anodic and cathodic potentials, which characterize the corrosion and deposition of electrodes, in real time through an online monitoring device to obtain the corrosion and scaling status of the electrodes. However, the monitoring of the anodic and cathodic potentials, which characterize the corrosion and deposition of electrodes, cannot be directly equivalent to the performance of the electrodes.

[0014] In summary, the operating status of the equalizing electrodes on the main cooling water pipe of the converter valve cannot be monitored, inevitably leading to a large amount of work involved in checking the equalizing electrodes during annual inspections. There is a lack of a method for real-time monitoring of the equalizing electrodes.

[0015] The information disclosed in the background section is only intended to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0016] To address at least one of the aforementioned problems, this application proposes a method and system for real-time monitoring of the equalizing electrode of a cooling water pipe.

[0017] According to a first aspect of this application, at least one embodiment of this application provides a method for real-time monitoring of the equalizing electrode of a cooling water pipe, wherein the cooling water pipe serves as the main cooling water pipe of a converter valve. The method includes: real-time monitoring of the leakage current, cooling water conductivity, DC bus voltage of the converter valve, and converter valve unlocking signal of the equalizing electrode of the main cooling water pipe flowing through the converter valve; calculating the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal, and comparing it with the real-time monitored leakage current; and determining the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison result and the converter valve unlocking signal.

[0018] For example, in some embodiments of this application, the real-time monitoring of the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve, the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal includes: monitoring the leakage current of each equalizing electrode individually, or monitoring the leakage current of multiple electrodes in the equalizing electrode in combination; monitoring only the leakage current of the equalizing electrode on the ground side, or monitoring both the leakage current of the equalizing electrode on the ground side and the leakage current of the equalizing electrode on the high-voltage side; selecting any one of multiple converter valves with the same voltage to ground on the high-voltage side for leakage current monitoring, or selecting at least two of multiple converter valves with the same voltage to ground on the high-voltage side for leakage current monitoring.

[0019] For example, in some embodiments of this application, the step of calculating the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal, and comparing it with the real-time monitored leakage current, includes: calculating the average value of the theoretical leakage current of the equalizing electrode based on the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal; extracting the instantaneous value of the leakage current from the real-time monitored leakage current; calculating the average value of the measured leakage current from the real-time monitored leakage current; calculating the overcurrent multiple of the leakage current based on the average value of the theoretical leakage current and the instantaneous value of the leakage current; and calculating the attenuation coefficient of the leakage current based on the average value of the theoretical leakage current and the average value of the measured leakage current.

[0020] For example, in some embodiments of this application, in the process of calculating the average value of the theoretical leakage current of the equalizing electrode based on the conductivity of the cooling water, the DC bus voltage of the converter valve, and the unlocking signal of the converter valve, the average value of the theoretical leakage current is calculated according to the following formula:

[0021] I L =K(σ) ×σ×S×(k×U) / L

[0022] Among them, I L The average value of the theoretical leakage current flowing through the equalizing electrode, σ is the conductivity of the cooling water in the main cooling water pipe monitored in real time, and K is the average value of the leakage current flowing through the equalizing electrode. (σ) The ratio of the leakage current flowing through the equalizing electrode under the conductivity of the cooling water to the total leakage current of the main cooling water pipe is given by S, where S is the inner cross-sectional area of ​​the main cooling water pipe, L is the length of the main cooling water pipe, U is the average value of the DC bus voltage of the converter valve monitored in real time, and k is the ratio of the DC voltage of the high-voltage side of the main cooling water pipe to ground determined according to the unlocking signal of the converter valve to the DC bus voltage of the converter valve.

[0023] For example, in some embodiments of this application, in the process of calculating the overcurrent multiple of the leakage current based on the average value of the theoretical leakage current and the instantaneous value of the leakage current, the overcurrent multiple of the leakage current is calculated according to the following formula:

[0024] b = I CS / I L ;

[0025] Where b is the overcurrent multiple, I CS I represents the instantaneous value of the leakage current of the equalizing electrode as monitored in real time. L This is the average value of the theoretical leakage current flowing through the equalizing electrode.

[0026] For example, in some embodiments of this application, in the process of calculating the attenuation coefficient of the leakage current based on the average value of the theoretical leakage current and the average value of the measured leakage current, the attenuation coefficient of the leakage current is calculated according to the following formula:

[0027] a = I C / I L ;

[0028] Where a is the attenuation coefficient, I C I is the average leakage current of the voltage equalization electrode as monitored in real time. L This is the average value of the theoretical leakage current flowing through the equalizing electrode.

[0029] For example, in some embodiments of this application, determining the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison results and the converter valve unlocking signal includes: determining the performance of the equalizing electrode on the ground side of the main cooling water pipe of the converter valve; and determining the performance of the equalizing electrode on the high-pressure side of the main cooling water pipe of the converter valve.

[0030] For example, in some embodiments of this application, determining the performance of the grounding-side equalizing electrode of the main cooling water pipe of the converter valve includes: determining whether the converter valve corresponding to the grounding-side equalizing electrode is unlocked; in response to the unlocking of the converter valve, determining whether to monitor the leakage current of the grounding-side equalizing electrode; if the leakage current of the grounding-side equalizing electrode is monitored, determining whether the overcurrent multiple of the leakage current of the grounding-side equalizing electrode exceeds a first threshold; if the overcurrent multiple exceeds the first threshold, counting the cumulative number of times the overcurrent multiple exceeds the first threshold, and determining whether the cumulative number reaches a first cumulative number; if the cumulative number reaches the first cumulative number, evaluating the performance of the grounding-side equalizing electrode as faulty.

[0031] For example, in some embodiments of this application, determining the performance of the grounding-side equalizing electrode of the main cooling water pipe of the converter valve further includes: if the overcurrent multiple does not exceed the first threshold, determining whether the attenuation coefficient of the grounding-side equalizing electrode is less than a second threshold; if the attenuation coefficient is less than the second threshold, determining that the performance of the grounding-side equalizing electrode is abnormal; and if the attenuation coefficient is greater than or equal to the second threshold, determining that the performance of the grounding-side equalizing electrode is normal.

[0032] For example, in some embodiments of this application, determining the performance of the grounding-side equalization electrode of the main cooling water pipe of the converter valve further includes: in the absence of monitoring the leakage current of the grounding-side equalization electrode of the current converter valve, determining whether the performance of the grounding-side equalization electrodes of multiple converter valves with the same voltage to ground and polarity as the current converter valve are all faulty or cannot be evaluated; in response to the fact that the performance of the grounding-side equalization electrodes of the multiple converter valves is not all faulty or cannot be evaluated, determining the performance of the grounding-side equalization electrode of the current converter valve as the lowest performance among the performance of the grounding-side equalization electrodes of the multiple converter valves, wherein the lowest performance includes normal and abnormal, and if the performance of the grounding-side equalization electrodes of the multiple converter valves includes normal and abnormal, the lowest performance is abnormal.

[0033] For example, in some embodiments of this application, determining the performance of the grounding-side equalization electrode of the main cooling water pipe of the converter valve further includes: in response to the converter valve not being unlocked or the performance of the grounding-side equalization electrodes of the plurality of converter valves being faulty or unassessable, determining whether the performance of the high-pressure-side equalization electrodes of the plurality of converter valves having the same voltage to ground as the current converter valve but opposite polarity is also faulty or unassessable; in response to the performance of the high-pressure-side equalization electrodes of the plurality of converter valves being faulty or unassessable, determining that the performance of the grounding-side equalization electrode of the current converter valve is unassessable; in response to the performance of the high-pressure-side equalization electrodes of the plurality of converter valves not being faulty or unassessable, determining that the performance of the grounding-side equalization electrode of the current converter valve is the lowest performance among the performance of the high-pressure-side equalization electrodes of the plurality of converter valves, wherein the lowest performance includes normal and abnormal, and in the case that the performance of the high-pressure-side equalization electrodes of the plurality of converter valves includes both normal and abnormal, the lowest performance is abnormal.

[0034] For example, in some embodiments of this application, determining the performance of the high-pressure side equalizing electrode of the main cooling water pipe of the converter valve includes: determining whether the converter valve corresponding to the high-pressure side equalizing electrode is unlocked; in response to the unlocking of the converter valve, determining whether to monitor the leakage current of the high-pressure side equalizing electrode; if the leakage current of the high-pressure side equalizing electrode is monitored, determining whether the overcurrent multiple of the leakage current of the high-pressure side equalizing electrode exceeds a first threshold; if the overcurrent multiple exceeds the first threshold, counting the cumulative number of times the overcurrent multiple exceeds the first threshold, and determining whether the cumulative number reaches a first cumulative number; if the cumulative number reaches the first cumulative number, determining that the performance of the high-pressure side equalizing electrode is faulty.

[0035] For example, in some embodiments of this application, determining the performance of the high-pressure side equalizing electrode of the main cooling water pipe of the converter valve further includes: if the overcurrent multiple does not exceed the first threshold, determining whether the attenuation coefficient of the high-pressure side equalizing electrode is less than a second threshold; if the attenuation coefficient is less than the second threshold, determining that the performance of the high-pressure side equalizing electrode is abnormal; and if the attenuation coefficient is greater than or equal to the second threshold, determining that the performance of the high-pressure side equalizing electrode is normal.

[0036] For example, in some embodiments of this application, determining the performance of the high-pressure side equalization electrode of the main cooling water pipe of the converter valve further includes: in the absence of monitoring the leakage current of the high-pressure side equalization electrode of the current converter valve, determining whether the performance of the high-pressure side equalization electrodes of multiple converter valves with the same voltage to ground and polarity as the current converter valve are all faulty or cannot be evaluated; in response to the fact that the performance of the high-pressure side equalization electrodes of the multiple converter valves are not all faulty or cannot be evaluated, determining the performance of the high-pressure side equalization electrode of the current converter valve as the lowest performance among the performance of the high-pressure side equalization electrodes of the multiple converter valves, wherein the lowest performance includes normal and abnormal, and if the performance of the high-pressure side equalization electrodes of the multiple converter valves includes normal and abnormal, the lowest performance is abnormal.

[0037] For example, in some embodiments of this application, determining the performance of the high-pressure side equalization electrode of the main cooling water pipe of the converter valve further includes: in response to the converter valve not being unlocked or the performance of the high-pressure side equalization electrodes of the plurality of converter valves being faulty or unassessable, determining whether the performance of the grounding side equalization electrodes of the plurality of converter valves having the same voltage to ground as the current converter valve but opposite polarity is also faulty or unassessable; in response to the performance of the grounding side equalization electrodes of the plurality of converter valves being faulty or unassessable, determining that the performance of the high-pressure side equalization electrode of the current converter valve is unassessable; in response to the performance of the grounding side equalization electrodes of the plurality of converter valves not being faulty or unassessable, determining that the performance of the high-pressure side equalization electrode of the current converter valve is the lowest performance among the performance of the grounding side equalization electrodes of the plurality of converter valves, wherein the lowest performance includes normal and abnormal, and in the case that the performance of the grounding side equalization electrodes of the plurality of converter valves includes both normal and abnormal, the lowest performance is abnormal.

[0038] According to a second aspect of this application, at least one embodiment of this application provides a system for real-time monitoring of the equalizing electrode of a cooling water pipe, for performing the method as described in any one of the first aspects, comprising: a leakage current sensor for real-time monitoring of the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve; a DC monitoring subsystem for acquiring the cooling water conductivity of the main cooling water pipe of the converter valve, the DC bus voltage of the converter valve, and a converter valve unlocking signal; and an online leakage current monitoring device, respectively connected to the leakage current sensor and the DC monitoring subsystem, for receiving the leakage current of the equalizing electrode sent by the leakage current sensor and the cooling water conductivity of the main cooling water pipe of the converter valve sent by the DC monitoring subsystem. The system is configured to: calculate the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the conductivity of the cooling water, the DC bus voltage of the converter valve, and the unlocking signal of the converter valve; compare it with the real-time monitored leakage current; and determine the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison result and the unlocking signal of the converter valve. The leakage current online monitoring device is also configured to receive the minimum performance of the equalizing electrode from multiple online leakage current monitoring devices on converter valves with the same high-voltage side voltage to ground but opposite polarity as the current converter valve, in order to evaluate the performance of the equalizing electrode of the main cooling water pipe of the current converter valve.

[0039] According to a third aspect of this application, at least one embodiment of this application provides a system for real-time monitoring of the equalizing electrode of a cooling water pipe, for performing the method as described in any one of the first aspects, comprising: a leakage current sensor for real-time monitoring of the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve; an online leakage current monitoring device connected to the leakage current sensor for receiving the leakage current of the equalizing electrode sent by the leakage current sensor; a DC monitoring subsystem for acquiring the cooling water conductivity of the main cooling water pipe of the converter valve, the DC bus voltage of the converter valve, and the converter valve unlocking signal; and an intelligent evaluation subsystem connected to the online leakage current monitoring device and the DC monitoring subsystem respectively for receiving the leakage current of the equalizing electrode sent by the leakage current sensor. The system includes the following parameters: leakage current, cooling water conductivity of the main cooling water pipe of the converter valve, DC bus voltage of the converter valve, and the converter valve unlocking signal sent by the DC monitoring subsystem. It is also used to calculate the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the cooling water conductivity, DC bus voltage of the converter valve, and the converter valve unlocking signal, and compare it with the real-time monitored leakage current. Furthermore, it is used to determine the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison result and the converter valve unlocking signal. The intelligent evaluation subsystem is also used to evaluate the performance of the equalizing electrode of the main cooling water pipe of the current converter valve based on the lowest performance of the equalizing electrodes of multiple converter valves with the same high-voltage side voltage to ground but opposite polarity as the current converter valve.

[0040] According to a fourth aspect of this application, at least one embodiment of this application provides a system for real-time monitoring of the equalizing electrode of a cooling water pipe, for performing the method as described in any one of the first aspects, comprising: a leakage current sensor for real-time monitoring of the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve; a DC monitoring subsystem for acquiring the cooling water conductivity of the main cooling water pipe of the converter valve, the DC bus voltage of the converter valve, and the converter valve unlocking signal; and an online leakage current monitoring device, respectively connected to the leakage current sensor and the DC monitoring subsystem, for receiving the leakage current of the equalizing electrode sent by the leakage current sensor, and the leakage current of the main cooling water pipe of the converter valve sent by the DC monitoring subsystem. The system includes the following parameters: cooling water conductivity, DC bus voltage of the converter valve, and the converter valve unlocking signal. It is also used to calculate the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the cooling water conductivity, DC bus voltage of the converter valve, and the converter valve unlocking signal, and compare it with the real-time monitored leakage current. Furthermore, it is used to determine the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison result and the converter valve unlocking signal. An intelligent evaluation subsystem is used to receive the minimum performance of the equalizing electrode from online leakage current monitoring devices on multiple converter valves with the same high-voltage side voltage to ground but opposite polarity as the current converter valve, in order to evaluate the performance of the equalizing electrode of the main cooling water pipe of the current converter valve.

[0041] This application provides a method and system for real-time monitoring of the equalizing electrodes of cooling water pipes. By monitoring the leakage current of the equalizing electrodes of the main cooling water pipes of the converter valves in real time and comparing the difference between the monitored leakage current and the theoretical value, the performance of the equalizing electrodes on the grounding side and high-pressure side of all converter valves can be obtained in real time. This replaces the traditional performance evaluation method of disassembling the equalizing electrodes to check the degree of scaling. The performance evaluation is more accurate and timely, and the workload of equalizing electrode maintenance is greatly reduced. Based on this, targeted maintenance strategies for equalizing electrodes can be formulated to achieve lean maintenance of equalizing electrodes.

[0042] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0043] The above and other objects, features, and advantages of this application will become more apparent from the detailed description of exemplary embodiments with reference to the accompanying drawings. The drawings described below are merely some embodiments of this application and are not intended to limit the scope of this application.

[0044] Figure 1 A flowchart illustrating a method for real-time monitoring of the equalizing electrode of the main cooling water pipe of a converter valve, as shown in an exemplary embodiment;

[0045] Figure 2 A schematic diagram of a pressure equalization electrode for the main cooling water pipe of a converter valve, illustrating an exemplary embodiment;

[0046] Figure 3 A schematic diagram illustrating an exemplary embodiment of the voltage equalization electrode on the grounding side of the main water inlet pipe and the current monitoring method;

[0047] Figure 4 A schematic diagram illustrating another exemplary embodiment of the voltage equalization electrode and current monitoring method on the grounding side of the main inlet pipe;

[0048] Figure 5 A schematic diagram illustrating another exemplary embodiment of the voltage equalization electrode and current monitoring method on the grounding side of the main inlet pipe;

[0049] Figure 6 A schematic diagram illustrating a method for comparing real-time monitored leakage current with theoretical values ​​in an exemplary embodiment is shown.

[0050] Figure 7 A schematic diagram illustrating a performance evaluation method for a voltage equalization electrode on the ground side of a converter valve, as shown in an exemplary embodiment;

[0051] Figure 8 A schematic diagram illustrating a performance evaluation method for a high-pressure side equalizing electrode of a converter valve, showing an exemplary embodiment;

[0052] Figure 9 A schematic diagram of a system for real-time monitoring of the equalizing electrode of the main cooling water pipe of an ultra-high voltage converter valve is shown in an exemplary embodiment.

[0053] Figure 10 A schematic diagram of another exemplary embodiment of a system for real-time monitoring of the equalizing electrode of the main cooling water pipe of an ultra-high voltage converter valve is shown.

[0054] Figure 11 A schematic diagram of another exemplary embodiment of a system for real-time monitoring of the equalizing electrode of the main cooling water pipe of an ultra-high voltage converter valve is shown.

[0055] Figure 12 A schematic diagram of an ultra-high voltage converter valve is shown as an exemplary embodiment. Detailed Implementation

[0056] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this application will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0057] The described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a full understanding of embodiments of this disclosure. However, those skilled in the art will recognize that the technical solutions of this disclosure can be practiced without one or more of these specific details, or other methods, components, materials, devices, etc. In these cases, well-known structures, methods, devices, implementations, materials, or operations will not be shown or described in detail.

[0058] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content, operations, or steps, nor do they necessarily need to be performed in the described order. For example, some operations or steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0059] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0060] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of exemplary embodiments, and the modules or processes in the drawings are not necessarily essential for implementing this application, and therefore cannot be used to limit the scope of protection of this application.

[0061] Figure 1 A flowchart illustrating an exemplary embodiment of a method for real-time monitoring of the equalizing electrode of the main cooling water pipe of a converter valve.

[0062] The cooling water pipe serves as the main cooling water pipe of the converter valve. The method for real-time monitoring of the equalizing electrode of the main cooling water pipe of the converter valve includes steps S10-S30, wherein:

[0063] In step S10: Real-time monitoring of the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve, the conductivity of the cooling water, the DC bus voltage of the converter valve, and the unlocking signal of the converter valve.

[0064] According to the example embodiment, a schematic diagram of the equalizing electrode of the main cooling water pipe of the converter valve is shown below. Figure 2 As shown.

[0065] Figure 2Taking one valve chamber of an ultra-high voltage converter valve as an example. The valve chamber includes six converter valves. Each converter valve's main cooling water pipe consists of two pipes: a main inlet pipe and a main outlet pipe. The main inlet pipes are numbered 101-106, and the main outlet pipes are numbered 201-206. Equalizing electrodes are installed at both ends of the main cooling water pipes; the upper equalizing electrode is grounded, and the lower equalizing electrode is connected to high voltage. The upper end of the main cooling water pipe is the grounded side, and the lower end is the high-voltage side. The DC voltage to ground on the high-voltage side is the same for all six converter valves. The upper equalizing electrode is the grounded side equalizing electrode, and the lower equalizing electrode is the high-voltage side equalizing electrode. Leakage current flowing into the grounded side equalizing electrode is positive, and current flowing out of the grounded side equalizing electrode is negative.

[0066] According to the example embodiment, a schematic diagram of the main inlet pipe equalization electrode and current monitoring method is shown below. Figure 3 As shown.

[0067] Figure 3 This is a schematic diagram of the equalizing electrodes of the main water inlet pipe 101. The main water inlet pipe 101 typically has three equalizing electrodes, namely equalizing electrodes 1011, 1012, and 1013, which monitor the currents I-1011, I-1012, and I-1013 of equalizing electrodes 1011, 1012, and 1013, respectively.

[0068] According to the example embodiment, another exemplary embodiment of the main inlet pipe equalizing electrode and current monitoring method is shown in the schematic diagram below. Figure 4 As shown.

[0069] Figure 4 The main water inlet pipe 101 typically has three equalizing electrodes: equalizing electrodes 1011, 1012, and 1013. The current I-101 of equalizing electrodes 1011, 1012, and 1013 is monitored together.

[0070] According to the example embodiment, another exemplary embodiment of the main inlet pipe equalizing electrode and current monitoring method is shown in the schematic diagram below. Figure 5 As shown.

[0071] Figure 5 The number of equalizing electrodes in the main water inlet pipe 101 is 1, numbered 1010, and the current I-101 of the equalizing electrode 1010 is monitored.

[0072] According to the example embodiment, real-time monitoring of the leakage current through the equalizing electrode of the main cooling water pipe of the converter valve includes: monitoring the leakage current of each equalizing electrode individually, or monitoring the leakage current of multiple equalizing electrodes in combination. Monitoring only the leakage current of the equalizing electrode on the grounding side, or monitoring both the leakage current of the equalizing electrode on the grounding side and the leakage current of the equalizing electrode on the high-voltage side. Selecting any one of multiple converter valves with the same high-voltage side voltage to ground for leakage current monitoring, or selecting at least two of multiple converter valves with the same high-voltage side voltage to ground for leakage current monitoring.

[0073] Figure 2 The monitoring method for leakage current on the grounding side of the main cooling water pipe of the converter valve in the valve hall shown includes the following combination:

[0074] Combination 1: Individually monitor the leakage current of each electrode in the equalizing electrode on the grounding side of the main cooling water pipe of the converter valve, such as... Figure 3 As shown, any one of the converter valves can be selected for leakage current monitoring. Taking the converter valves numbered 101 and 201 on the main inlet and outlet water pipes as an example, the monitored leakage currents include: I-1011~I-1013 and I-2011~I-2013.

[0075] Combination 2: Combine the leakage current of each electrode in the equalizing electrode on the grounding side of the main cooling water pipe of the converter valve, such as... Figure 4 As shown or Figure 5 As shown, any one of the converter valves can be selected for leakage current monitoring. Taking the converter valves numbered 101 and 201 on the main inlet and outlet water pipes as an example, the monitored leakage currents include: I-101 and I-201.

[0076] Combination 3: Individually monitor the leakage current of each electrode of the equalizing electrode on the grounding side of the main cooling water pipe of the converter valve, such as... Figure 3 As shown, two or more converter valves are selected for monitoring. Taking six converter valves as an example, the monitored leakage currents include: I-1011~I-1013, I-2011~I-2013, I-1021~I-1023, I-2021~I-2023, I-1031~I-1033, I-2031~I-2033, I-1041~I-1043, I-2041~I-2043, I-1051~I-1053, I-2051~I-2053, I-1061~I-1063, I-2061~I-2063.

[0077] Combination 4: Combine the leakage current of each electrode of the equalizing electrode on the grounding side of the main cooling water pipe of the converter valve, such as... Figure 4 As shown or Figure 5As shown, two or more converter valves are selected for monitoring. Taking a number of converter valves of 6 as an example, the monitored leakage currents include: I-101~I-106 and I-201~I-206.

[0078] Similarly, if we choose to monitor the leakage current of both the equalizing electrode on the grounding side and the equalizing electrode on the high-voltage side, then... Figures 3-5 Based on this, the leakage current of the equalizing electrode on the high-pressure side of the inlet pipe of the converter valve is monitored simultaneously.

[0079] According to the example embodiment, Figure 2 The converter valves in the valve hall shown share a single valve cooling system. The cooling water has the same conductivity and is provided by the valve cooling system. The DC pole bus voltage of the converter valve and the converter valve unlocking signal are provided by the DC control and protection system.

[0080] In step S20: the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve is calculated based on the conductivity of the cooling water, the DC bus voltage of the converter valve, and the unlocking signal of the converter valve, and compared with the leakage current monitored in real time.

[0081] According to the example embodiment, a schematic diagram of the method for comparing the real-time monitored leakage current with the theoretical value of the leakage current is shown below. Figure 6 As shown, steps S201-S205 are included:

[0082] In step S201: The average value of the theoretical leakage current I of the equalizing electrode is calculated based on the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal. L .

[0083] I L =K (σ) ×σ×S×U S / L=K (σ) ×σ×S×(k×U) / L.

[0084] Among them, I L The average value of the theoretical leakage current flowing through the equalizing electrode, σ is the conductivity of the cooling water in the main cooling water pipe monitored in real time, and K is the average value of the leakage current flowing through the equalizing electrode. (σ) Let S be the proportion of the leakage current flowing through the equalizing electrode at the given cooling water conductivity to the total leakage current of the main cooling water pipe, and let L be the inner cross-sectional area of ​​the main cooling water pipe, L be the length of the main cooling water pipe, and U be the value of U. S I is the DC voltage to ground on the high-pressure side of the main cooling water pipe, k is the ratio of the DC voltage to ground on the high-pressure side of the main cooling water pipe to the DC bus voltage of the converter valve, determined according to the converter valve unlocking signal, and U is the average value of the DC bus voltage of the converter valve monitored in real time. L σ and U are all average values.

[0085] According to the example embodiment, the average value I of the theoretical leakage current of the equalizing electrode is calculated. L The method is applicable to both the grounding side equalization electrode and the high-voltage side equalization electrode.

[0086] According to the example embodiment, the same converter valve K (σ) K is only related to the cooling water conductivity σ. (σ) = f(σ).

[0087] According to the example embodiment, the DC bus voltage U of the converter valve has two polarities; typically, pole 1 is positive and pole 2 is negative. Figure 12 As shown, the theoretical value of the leakage current through the equalizing electrode of the main cooling water pipe of the converter valve also includes positive and negative polarities.

[0088] According to the example embodiment, taking an ultra-high voltage converter valve as an example, each pole includes a high-end valve hall and a low-end valve hall, such as... Figure 12 As shown. When k1+k2≠0, k=(0.5×k1+k2) / (k1+k2) for the high-end valve hall; k=0.5×k2 / (k1+k2) for the low-end valve hall; when k1+k2=0, k=0;

[0089] Where k1 and k2 are coefficients of the same polarity. When the high-end valve hall converter valve is unlocked, k1 = 1, and when the converter valve is not unlocked, k1 = 0. When the low-end valve hall converter valve is unlocked, k2 = 1, and when the converter valve is not unlocked, k2 = 0.

[0090] According to the example embodiment, by using different combinations 1 to 4, the average value I of the theoretical value corresponding to different leakage currents can be obtained. L .

[0091] In step S202: Extract the instantaneous value I of the leakage current from the real-time monitored leakage current. CS .

[0092] According to some embodiments, the sampling rate of leakage current can be 1MHz.

[0093] In step S203: Calculate the average value I of the measured leakage current from the real-time monitored leakage current. C .

[0094] According to some embodiments, the average value I of the measured leakage current is calculated. C The average value of the measured leakage current within 20ms can be taken.

[0095] In step S204: the overcurrent multiple b of the leakage current is calculated based on the average value of the theoretical leakage current and the instantaneous value of the leakage current.

[0096] According to the example embodiment, b = I CS / IL .

[0097] Where b is the overcurrent multiple, I CS I represents the instantaneous value of the leakage current of the equalizing electrode as monitored in real time. L This represents the average value of the theoretical leakage current flowing through the equalizing electrode.

[0098] In step S205: the attenuation coefficient α of the leakage current is calculated based on the average value of the theoretical leakage current and the average value of the measured leakage current.

[0099] According to the example embodiment, a = I C / I L .

[0100] Where a is the attenuation coefficient, I C I represents the average leakage current of the voltage equalization electrode as monitored in real time. L This represents the average value of the theoretical leakage current flowing through the equalizing electrode.

[0101] In step S30: the performance of the equalizing electrode of the main cooling water pipe of the converter valve is determined based on the comparison results and the converter valve unlocking signal.

[0102] According to an example embodiment, the equalizing electrode includes an electrode that monitors leakage current in real time and an electrode that does not monitor leakage current.

[0103] Based on the comparison results and the converter valve unlocking signal, determine the performance of the equalizing electrode of the main cooling water pipe of the converter valve, including: 1. Determine the performance of the equalizing electrode on the ground side of the main cooling water pipe of the converter valve; 2. Determine the performance of the equalizing electrode on the high-pressure side of the main cooling water pipe of the converter valve.

[0104] A schematic diagram of the performance evaluation method for the grounding side equalization electrode of the main cooling water pipe of the converter valve is shown below. Figure 7 As shown, steps S301-S313 are included:

[0105] In step S301: Determine whether the converter valve corresponding to the grounding side equalization electrode is unlocked.

[0106] According to some embodiments, the converter valve unlock signal is 1, indicating that the converter valve is unlocked; the converter valve unlock signal is 0, indicating that the converter valve is not unlocked. If a converter valve unlock signal is received, proceed to step S302; if a converter valve not unlock signal is received, proceed to step S311.

[0107] In step S302: In response to the unlocking of the converter valve, it is determined whether to monitor the leakage current of the grounding side equalization electrode.

[0108] According to the example embodiment, if the leakage current of the grounding side equalization electrode of the converter valve is monitored, proceed to step S303; if the leakage current of the grounding side equalization electrode of the converter valve is not monitored, proceed to step S309.

[0109] In step S303: while monitoring the leakage current of the grounding side equalizing electrode, it is determined whether the overcurrent multiple of the leakage current of the grounding side equalizing electrode exceeds the first threshold.

[0110] According to some embodiments, a typical value of the first threshold is 1.3. If the overcurrent multiple b exceeds the first threshold, it is determined that the equalizing electrode has discharged. If the overcurrent multiple b exceeds the first threshold, proceed to step S304; if the overcurrent multiple b does not exceed the first threshold, proceed to step S305.

[0111] In step S304: when the overcurrent multiple exceeds the first threshold, the cumulative number of times the overcurrent multiple exceeds the first threshold is counted, and it is determined whether the cumulative number has reached the first cumulative number.

[0112] According to the example embodiment, if the number of times the overcurrent multiple b exceeds the first threshold reaches the first cumulative number, the performance of the current converter valve grounding side equalization electrode is evaluated as a fault.

[0113] According to some embodiments, the typical value for the first cumulative count is 10. If the performance evaluation is deemed faulty, the performance of the current converter valve's ground side equalizing electrode remains faulty until manual reset, after which the cumulative count is reset to zero.

[0114] In step S305: if the overcurrent multiple does not exceed the first threshold, determine whether the attenuation coefficient of the grounding side voltage equalization electrode is less than the second threshold.

[0115] According to the example embodiment, if the overcurrent multiple does not exceed a first threshold, it is determined whether the attenuation coefficient of the equalizing electrode on the ground side of the converter valve is less than a second threshold. A typical value for the second threshold is 0.8. If the attenuation coefficient 'a' is less than the second threshold, the equalizing electrode is determined to be in one of the following states: severe scaling, severe corrosion, electrode breakage, or equipotential bonding line breakage. If the attenuation coefficient 'a' is less than the second threshold, proceed to step S306; if the attenuation coefficient 'a' is greater than or equal to the second threshold, proceed to step S307.

[0116] In step S306: it is determined that the performance of the grounding side equalizing electrode is abnormal.

[0117] In step S307: it is determined that the performance of the grounding side equalizing electrode is normal.

[0118] In step S308: the performance of the grounding side equalizing electrode is given.

[0119] According to the example embodiment, the worst performance among steps S304, S306, and S307 is taken as the performance of the grounding side equalization electrode of the current converter valve. The order of performance from best to worst is normal, abnormal, and faulty.

[0120] In step S309: Determine whether the performance of the grounding side equalization electrodes of multiple converter valves that have the same voltage to ground and polarity as the current converter valve high-pressure side are all faulty or cannot be evaluated.

[0121] According to the example embodiment, without monitoring the leakage current of the grounding side equalization electrode of the current converter valve, it is determined whether the performance of the grounding side equalization electrodes of multiple converter valves with the same voltage to ground and polarity as the current converter valve are all faulty or cannot be evaluated. Figure 2 In the valve hall shown, the high-pressure side voltage to ground of the six converter valves is the same. Taking the current converter valve main water pipe number as 101 and 201 as an example, the other converter valve main water pipe numbers are 102 to 106 and 202 to 206. If the performance of the equalizing electrodes on the grounding side of the other converter valves is faulty or cannot be evaluated, then proceed to step S311. If not all of them are faulty or cannot be evaluated, then proceed to step S310.

[0122] In step S310: the performance of the current converter valve grounding side equalizing electrode is determined to be the lowest among the performance of the grounding side equalizing electrodes of multiple converter valves.

[0123] According to the example embodiment, in response to the fact that the performance of the grounding-side equalization electrodes of multiple converter valves is not all faulty or unassessable, the performance of the current grounding-side equalization electrode of the converter valve is determined to be the lowest performance among the performance of the grounding-side equalization electrodes of the multiple converter valves. The lowest performance includes both normal and abnormal performance, and if the performance of the grounding-side equalization electrodes of the multiple converter valves includes both normal and abnormal performance, the lowest performance is abnormal. The current converter valves are main water pipes numbered 101 and 201, and the performance of the grounding-side equalization electrodes is the lowest performance among the grounding-side equalization electrodes of main water pipes 102-106 and 201-206. The lowest performance is the performance excluding faults, and the order from best to worst is normal, then abnormal.

[0124] In step S311: Determine whether the performance of the equalizing electrodes on the high-pressure side of multiple converter valves that have the same voltage to ground as the current converter valve but opposite polarity is faulty or cannot be evaluated.

[0125] According to the example embodiment, in response to the converter valve not being unlocked or the performance of the grounding side equalization electrodes of multiple converter valves being faulty or unevaluable, it is determined whether the performance of the high-pressure side equalization electrodes of multiple converter valves with the same high-pressure side voltage to ground as the current converter valve but opposite polarity is also faulty or unevaluable. If the performance of the high-pressure side equalization electrodes of other converter valves is also faulty or unevaluable, then proceed to step S313; otherwise, proceed to step S312.

[0126] In step S312: the performance of the grounding side equalization electrode of the current converter valve is determined to be the lowest performance among the performance of the high-voltage side equalization electrodes of multiple converter valves that have the same voltage to ground on the high-voltage side but opposite polarity as the current converter valve.

[0127] According to the example embodiment, in response to the fact that the performance of the high-pressure side equalization electrodes of multiple converter valves is not all faulty or unassessable, the performance of the current grounding side equalization electrode of the converter valve is determined to be the lowest performance among the performances of the high-pressure side equalization electrodes of the multiple converter valves. The lowest performance includes both normal and abnormal performance, and when the performance of the high-pressure side equalization electrodes of the multiple converter valves includes both normal and abnormal performance, the lowest performance is abnormal. The current converter valves are main water pipes numbered 101 and 201, and the performance of the grounding side equalization electrodes is taken as the lowest performance among the high-pressure side equalization electrodes of main water pipes 102-106 and 201-206. The lowest performance is the performance excluding faults, and the order from best to worst is normal, then abnormal.

[0128] In step S313: It is determined that the performance of the grounding side equalizing electrode cannot be evaluated.

[0129] According to the example embodiment, if the current converter valve is not unlocked, or if the leakage current of the grounding side equalizing electrode of the current converter valve is not monitored, and the performance of the grounding side equalizing electrodes of multiple converter valves with the same voltage to ground and polarity as the current converter valve is faulty or cannot be evaluated, and the performance of the high-voltage side equalizing electrodes of multiple converter valves with the same voltage to ground and polarity as the current converter valve is faulty or cannot be evaluated, then the performance of the grounding side equalizing electrode of the current converter valve is determined to be unevaluable.

[0130] If the current converter valve is not unlocked, or the leakage current of the grounding side equalizing electrode of the current converter valve is not monitored, and the performance of the grounding side equalizing electrode and the high-pressure side equalizing electrode of the main water pipes 102-106 and 202-206 is faulty or cannot be evaluated, then the performance of the grounding side equalizing electrode of the current converter valve main water pipes 101 and 201 cannot be evaluated.

[0131] According to the example embodiment, a schematic diagram of the performance evaluation method for the high-pressure side equalization electrode of the main cooling water pipe of the converter valve is shown below. Figure 8 As shown, steps S314-S326 are included:

[0132] In step S314: Determine whether the converter valve corresponding to the high-voltage side equalization electrode is unlocked.

[0133] According to some embodiments, the converter valve unlock signal is 1, indicating that the converter valve is unlocked; the converter valve unlock signal is 0, indicating that the converter valve is not unlocked. If a converter valve unlock signal is received, proceed to step S315; if a converter valve not unlock signal is received, proceed to step S324.

[0134] In step S315: In response to the unlocking of the converter valve, it is determined whether to monitor the leakage current of the high-voltage side equalization electrode.

[0135] According to the example embodiment, if the leakage current of the high-pressure side equalization electrode of the converter valve is monitored, proceed to step S316; if the leakage current of the high-pressure side equalization electrode of the converter valve is not monitored, proceed to step S322.

[0136] In step S316: While monitoring the leakage current of the high-voltage side equalizing electrode, it is determined whether the overcurrent multiple of the leakage current of the high-voltage side equalizing electrode exceeds the first threshold.

[0137] According to some embodiments, a typical value of the first threshold is 1.3. If the overcurrent multiple b exceeds the first threshold, it is determined that the equalizing electrode has discharged. If the overcurrent multiple b exceeds the first threshold, proceed to step S317; if the overcurrent multiple b does not exceed the first threshold, proceed to step S318.

[0138] In step S317: when the overcurrent multiple exceeds the first threshold, the cumulative number of times the overcurrent multiple exceeds the first threshold is counted, and it is determined whether the cumulative number has reached the first cumulative number.

[0139] According to the example embodiment, if the number of times the overcurrent multiple b exceeds the first threshold reaches the first cumulative number, the performance of the current converter valve high-pressure side equalization electrode is evaluated as a fault.

[0140] According to some embodiments, the typical value for the first cumulative count is 10. If the performance evaluation is deemed faulty, the performance of the high-pressure side equalizing electrode of the current converter valve remains faulty until manual reset, after which the cumulative count is reset to zero.

[0141] In step S318: if the overcurrent multiple does not exceed the first threshold, determine whether the attenuation coefficient of the high-voltage side equalizing electrode is less than the second threshold.

[0142] According to the example embodiment, if the overcurrent multiple does not exceed a first threshold, it is determined whether the attenuation coefficient of the high-pressure side equalizing electrode of the converter valve is less than a second threshold. A typical value for the second threshold is 0.8. If the attenuation coefficient 'a' is less than the second threshold, the equalizing electrode is determined to be in one of the following states: severe scaling, severe corrosion, electrode breakage, or equipotential line breakage. If the attenuation coefficient 'a' is less than the second threshold, proceed to step S319; if the attenuation coefficient 'a' is greater than or equal to the second threshold, proceed to step S320.

[0143] In step S319: the performance of the high-voltage side equalizing electrode is determined to be abnormal.

[0144] In step S320: it is determined that the performance of the high-voltage side equalizing electrode is normal.

[0145] In step S321: the performance of the high-voltage side equalizing electrode is given.

[0146] According to the example embodiment, the worst performance among steps S317, S319, and S320 is taken as the performance of the high-pressure side equalizing electrode of the current converter valve. The order of performance from best to worst is normal, abnormal, and faulty.

[0147] In step S22: Determine whether the performance of the equalizing electrodes on the high-pressure side of multiple converter valves that have the same voltage to ground and polarity as the current converter valve are all faulty or cannot be evaluated.

[0148] According to the example embodiment, without monitoring the leakage current of the high-pressure side equalization electrode of the current converter valve, it is determined whether the performance of the high-pressure side equalization electrodes of multiple converter valves with the same high-pressure side voltage to ground and the same polarity as the current converter valve is faulty or cannot be evaluated. Figure 2 In the valve hall shown, the high-pressure side voltage to ground of the six converter valves is the same. Taking the current converter valve main water pipe number as 101 and 201 as an example, the other converter valve main water pipe numbers are 102 to 106 and 202 to 206. If the performance of the equalizing electrodes on the high-pressure side of the other converter valves is faulty or cannot be evaluated, then proceed to step S324. If not all of them are faulty or cannot be evaluated, then proceed to step S323.

[0149] In step S323: the performance of the current high-pressure side equalizing electrode of the converter valve is determined to be the lowest among the performance of the high-pressure side equalizing electrodes of multiple converter valves.

[0150] According to the example embodiment, in response to the fact that the performance of the high-pressure side equalization electrodes of multiple converter valves is not all faulty or unassessable, the performance of the current high-pressure side equalization electrode of the converter valve is determined to be the lowest performance among the performance of the high-pressure side equalization electrodes of multiple converter valves. The lowest performance includes both normal and abnormal performance, and if the performance of the high-pressure side equalization electrodes of multiple converter valves includes both normal and abnormal performance, the lowest performance is abnormal. The current converter valves are main water pipes numbered 101 and 201, and the performance of the high-pressure side equalization electrodes is the lowest performance among the high-pressure side equalization electrodes of main water pipes 102-106 and 201-206. The lowest performance is the performance excluding faults, and the order from best to worst is normal, then abnormal.

[0151] In step S324: Determine whether the performance of the grounding side equalization electrodes of multiple converter valves that have the same high-voltage side voltage to ground as the current converter valve but opposite polarity is faulty or cannot be evaluated.

[0152] According to the example embodiment, in response to the converter valve not being unlocked or the performance of the high-pressure side equalization electrodes of multiple converter valves being faulty or unevaluable, it is determined whether the performance of the grounding side equalization electrodes of multiple converter valves with the same high-pressure side voltage to ground but opposite polarity as the current converter valve is also faulty or unevaluable. If the performance of the grounding side equalization electrodes of other converter valves is also faulty or unevaluable, then proceed to step S326; if not all of them are faulty or unevaluable, then proceed to step S325.

[0153] In step S325: the performance of the high-pressure side equalization electrode of the current converter valve is determined to be the lowest performance among the performance of the grounding side equalization electrodes of multiple converter valves that have the same high-pressure side voltage to ground but opposite polarity as the current converter valve.

[0154] According to the example embodiment, in response to the fact that the performance of the grounding-side equalization electrodes of multiple converter valves is not all faulty or unassessable, the performance of the current high-pressure-side equalization electrode of the converter valve is determined to be the lowest performance among the performance of the grounding-side equalization electrodes of the multiple converter valves. The lowest performance includes both normal and abnormal performance, and when the performance of the grounding-side equalization electrodes of the multiple converter valves includes both normal and abnormal performance, the lowest performance is abnormal. For the current converter valves with main water pipe numbers 101 and 201, the performance of the high-pressure-side equalization electrodes is taken as the lowest performance among the grounding-side equalization electrodes of main water pipes 102-106 and 201-206. The lowest performance is the performance excluding faults, and the order from best to worst is normal, then abnormal.

[0155] In step S313: the performance of the high-voltage side equalizing electrode is determined to be unevaluable.

[0156] According to the example embodiment, if the current converter valve is not unlocked, or if the leakage current of the high-pressure side equalizing electrode of the current converter valve is not monitored, and the performance of the high-pressure side equalizing electrodes of multiple converter valves with the same voltage to ground and polarity as the current converter valve is faulty or cannot be evaluated, and the performance of the grounding side equalizing electrodes of multiple converter valves with the same voltage to ground and polarity as the current converter valve is faulty or cannot be evaluated, then the performance of the high-pressure side equalizing electrode of the current converter valve is determined to be unevaluable.

[0157] If the current converter valve is not unlocked, or the leakage current of the high-pressure side equalizing electrode of the current converter valve is not monitored, and the performance of the grounding side equalizing electrode and the high-pressure side equalizing electrode of the main water pipes 102-106 and 202-206 is faulty or cannot be evaluated, then the performance of the high-pressure side equalizing electrodes of the current converter valve main water pipes 101 and 201 cannot be evaluated.

[0158] According to the example embodiment, Figure 7 and Figure 8 The performance determination of the grounding-side equalizing electrode and the high-voltage-side equalizing electrode is performed simultaneously. Figure 7 If the converter valve corresponding to the grounding side equalization electrode is not unlocked, or if the performance of the grounding side equalization electrodes of multiple converter valves with the same high-voltage side voltage to ground and the same polarity as the current converter valve is faulty or cannot be evaluated, then... Figure 8 The performance of the high-pressure side equalization electrodes of several converter valves identified in the study is used to evaluate the grounding side equalization electrodes. Similarly, in Figure 8 If the converter valve corresponding to the medium- and high-voltage side equalization electrode is not unlocked, or if the performance of the equalization electrodes on the high-voltage side of multiple converter valves with the same voltage to ground and polarity as the current converter valve is faulty or cannot be evaluated, then... Figure 7 The performance of the grounding-side equalizing electrodes of several converter valves identified in the study was used to evaluate the high-voltage-side equalizing electrodes.

[0159] Figure 9 This is a schematic diagram of a system for real-time monitoring of the equalizing electrode of the main cooling water pipe of an ultra-high voltage converter valve, illustrating an exemplary embodiment.

[0160] like Figure 9 As shown, the system for real-time monitoring of the equalizing electrode of the main cooling water pipe of the UHV converter valve includes a leakage current sensor, a leakage current online monitoring device, and a DC monitoring subsystem.

[0161] A leakage current sensor is used to monitor the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve in real time.

[0162] The DC monitoring subsystem is used to acquire the cooling water conductivity of the main cooling water pipe of the converter valve, the DC pole bus voltage of the converter valve, and the converter valve unlocking signal.

[0163] The online leakage current monitoring device is connected to a leakage current sensor and a DC monitoring subsystem, respectively. It is used to receive the leakage current of the equalizing electrode sent by the leakage current sensor and the cooling water conductivity of the main cooling water pipe of the converter valve, the DC bus voltage of the converter valve, and the converter valve unlocking signal sent by the DC monitoring subsystem. It is also used to calculate the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal, and compare it with the real-time monitored leakage current. It is also used to determine the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison results and the converter valve unlocking signal.

[0164] The online leakage current monitoring device is also used to receive the minimum performance of the equalizing electrode from multiple online leakage current monitoring devices on multiple converter valves that have the same voltage to ground on the high-pressure side of the current converter valve but opposite polarity, in order to evaluate the performance of the equalizing electrode of the main cooling water pipe of the current converter valve.

[0165] According to the example embodiment, taking a converter station comprising four valve chambers as an example, leakage current sensors are arranged on the grounding side of the main cooling water pipes of the converter valves in the four valve chambers according to any combination of monitoring methods from combination 1 to combination 4 to collect leakage current. The valve chamber leakage current sensors are used to send the collected leakage current of the equalizing electrode to the corresponding online leakage current monitoring device.

[0166] According to the example embodiment, the DC monitoring subsystem sends the cooling water conductivity of each valve chamber, the converter valve unlocking signal, and the DC pole bus voltage to the corresponding online leakage current monitoring device.

[0167] According to the example embodiment, the minimum performance of the online leakage current monitoring device at the high end of electrode 1 and the online leakage current monitoring device at the high end of electrode 2 in transmitting the voltage equalization electrode to each other; the minimum performance of the online leakage current monitoring device at the low end of electrode 1 and the online leakage current monitoring device at the low end of electrode 2 in transmitting the voltage equalization electrode to each other.

[0168] According to the example embodiment, taking the high end of pole 1 as an example, after receiving the leakage current of the equalizing electrode sent by the leakage current sensor of the high end valve hall of pole 1, the conductivity of the cooling water of the high end of pole 1 sent by the DC monitoring subsystem, the unlocking signal of the converter valve of the high end of pole 1, and the DC pole bus voltage, the leakage current online monitoring device calculates the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve of the high end of pole 1, and compares it with the leakage current monitored in real time. Based on the comparison result, the performance of the equalizing electrode of the main cooling water pipe of the converter valve of the high end of pole 1 is determined. If the converter valve in the high end valve hall of pole 1 is not unlocked, or the leakage current is not monitored, and the performance of the equalizing electrode of the main cooling water pipe cannot be determined based on other converter valves in this pole, the high end leakage current online monitoring device receives the minimum performance of the equalizing electrode sent by the high end leakage current online monitoring device of pole 2, and evaluates the performance of the equalizing electrode of the main cooling water pipe of the high end converter valve of pole 1.

[0169] The method for judging the performance of the grounding side equalizing electrode and the high-voltage side equalizing electrode of the high end of pole 2, the low end of pole 1, and the low end of pole 2 is the same as that in the embodiment of the high end of pole 1.

[0170] The system for real-time monitoring of the equalizing electrode of the high-pressure converter valve cooling water pipe is used to execute the method for real-time monitoring of the equalizing electrode of the high-pressure converter valve cooling water pipe as described above. Therefore, the real-time monitoring of the equalizing electrode of the high-pressure converter valve cooling water pipe will not be described again here.

[0171] Figure 10 This diagram illustrates another exemplary embodiment of a system for real-time monitoring of the equalizing electrode of the main cooling water pipe of an ultra-high voltage converter valve.

[0172] like Figure 10 As shown, the system for real-time monitoring of the equalizing electrode of the main cooling water pipe of the UHV converter valve includes a leakage current sensor, a leakage current online monitoring device, a DC monitoring subsystem, and an intelligent evaluation subsystem.

[0173] A leakage current sensor is used to monitor the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve in real time.

[0174] An online leakage current monitoring device is connected to a leakage current sensor to receive the leakage current from the grounding side equalizing electrode sent by the leakage current sensor.

[0175] The DC monitoring subsystem is used to acquire the cooling water conductivity of the main cooling water pipe of the converter valve, the DC pole bus voltage of the converter valve, and the converter valve unlocking signal.

[0176] The intelligent evaluation subsystem is connected to the online leakage current monitoring device and the DC monitoring subsystem, respectively. It is used to receive the leakage current of the equalizing electrode sent by the leakage current sensor, as well as the cooling water conductivity of the main cooling water pipe of the converter valve, the DC bus voltage of the converter valve, and the converter valve unlocking signal sent by the DC monitoring subsystem. It is also used to calculate the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal, and compare it with the real-time monitored leakage current. It is also used to determine the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison results and the converter valve unlocking signal.

[0177] The intelligent evaluation subsystem is also used to evaluate the performance of the equalization electrode of the main cooling water pipe of the current converter valve based on the lowest performance of the equalization electrodes of multiple converter valves with the same voltage to ground on the high-pressure side but opposite polarity as the current converter valve.

[0178] According to the example embodiment, taking a converter station comprising four valve chambers as an example, a set of leakage current sensors is arranged on the grounding side of the main cooling water pipes of the converter valves in the four valve chambers, according to any combination of monitoring methods from combination 1 to combination 4, to collect leakage current. The valve chamber leakage current sensors are used to send the collected leakage current of the grounding side equalizing electrode to the corresponding online leakage current monitoring device.

[0179] According to the example embodiment, the online leakage current monitoring device collects and summarizes the leakage current data of the equalizing electrodes of each valve chamber and sends it to the intelligent evaluation subsystem.

[0180] According to the example embodiment, the DC monitoring subsystem sends the cooling water conductivity of each valve chamber, the converter valve unlocking signal, and the DC pole bus voltage to the intelligent evaluation subsystem.

[0181] According to the example embodiment, taking the high-end of pole 1 as an example, after the intelligent evaluation subsystem receives the leakage current of the equalizing electrode sent by the online leakage current monitoring device of pole 1, the conductivity of the cooling water of pole 1 high-end sent by the DC monitoring subsystem, the unlocking signal of pole 1 high-end converter valve, and the DC pole bus voltage, it calculates the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of pole 1 high-end converter valve, and compares it with the leakage current monitored in real time. Based on the comparison result, the performance of the equalizing electrode of the main cooling water pipe of pole 1 high-end converter valve is determined.

[0182] Furthermore, if the converter valve in the high-end valve hall of pole 1 is not unlocked, or the leakage current is not monitored, and the performance of the equalizing electrode of the main cooling water pipe cannot be determined based on other converter valves in this pole, the intelligent evaluation subsystem uses the minimum performance of the equalizing electrode of the main cooling water pipe of the high-end converter valve of pole 2 to evaluate the performance of the equalizing electrode of the main cooling water pipe of the high-end converter valve of pole 1.

[0183] The intelligent evaluation subsystem uses the same method to determine the performance of the grounding side equalizing electrode and the high-voltage side equalizing electrode of the main cooling water pipe of the converter valve at the low end of pole 1, the high end of pole 2, and the low end of pole 2.

[0184] The system for real-time monitoring of the equalizing electrode of the high-pressure converter valve cooling water pipe is used to execute the method for real-time monitoring of the equalizing electrode of the high-pressure converter valve cooling water pipe as described above. Therefore, the real-time monitoring of the equalizing electrode of the high-pressure converter valve cooling water pipe will not be described again here.

[0185] Figure 11 This diagram illustrates another exemplary embodiment of a system for real-time monitoring of the equalizing electrode of the main cooling water pipe of an ultra-high voltage converter valve.

[0186] like Figure 11 As shown, the system for real-time monitoring of the equalizing electrode of the main cooling water pipe of the UHV converter valve includes a leakage current sensor, a leakage current online monitoring device, a DC monitoring subsystem, and an intelligent evaluation subsystem.

[0187] A leakage current sensor is used to monitor the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve in real time.

[0188] The DC monitoring subsystem is used to acquire the cooling water conductivity of the main cooling water pipe of the converter valve, the DC pole bus voltage of the converter valve, and the converter valve unlocking signal.

[0189] The online leakage current monitoring device is connected to a leakage current sensor and a DC monitoring subsystem, respectively. It is used to receive the leakage current of the equalizing electrode sent by the leakage current sensor, and the cooling water conductivity of the main cooling water pipe of the converter valve, the DC bus voltage of the converter valve, and the converter valve unlocking signal sent by the DC monitoring subsystem. It is also used to calculate the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal, and compare it with the real-time monitored leakage current. It is also used to determine the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison result and the converter valve unlocking signal.

[0190] The intelligent evaluation subsystem is used to receive the minimum performance of the equalizing electrodes from multiple online leakage current monitoring devices on multiple converter valves that have the same high-pressure side voltage to ground but opposite polarity as the current converter valve, in order to evaluate the performance of the equalizing electrodes on the main cooling water pipe of the current converter valve.

[0191] According to the example embodiment, taking a converter station comprising four valve chambers as an example, a set of leakage current sensors is arranged on the grounding side of the main cooling water pipe of the converter valve in each of the four valve chambers, according to any combination of monitoring methods from combination 1 to combination 4, to collect leakage current. The valve chamber leakage current sensors are used to send the collected leakage current of the equalizing electrode to the corresponding online leakage current monitoring device.

[0192] According to the example embodiment, the DC monitoring subsystem sends the cooling water conductivity of each valve chamber, the converter valve unlocking signal, and the DC pole bus voltage to the corresponding online leakage current monitoring device.

[0193] According to the example embodiment, taking the high end of pole 1 as an example, after the online leakage current monitoring device receives the leakage current of the equalizing electrode sent by the leakage current sensor of the high end of pole 1 valve hall, the conductivity of the cooling water of the high end of pole 1 sent by the DC monitoring subsystem, the unlocking signal of the high end of pole 1 converter valve, and the DC pole bus voltage, it calculates the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the high end of pole 1 converter valve, and compares it with the leakage current monitored in real time. Based on the comparison result, the performance of the equalizing electrode of the main cooling water pipe of the high end of pole 1 converter valve is determined.

[0194] The method for judging the performance of the equalizing electrodes at the high end of electrode 2, the low end of electrode 1, and the low end of electrode 2 is the same as that for the embodiment at the high end of electrode 1. Furthermore, each online leakage current monitoring device sends the performance data of the equalizing electrodes of the main cooling water pipe of the converter valve to the intelligent evaluation subsystem.

[0195] According to the example embodiment, after the intelligent evaluation subsystem receives the performance data of the equalizing electrode of the main cooling water pipe of the converter valve sent by each online leakage current monitoring device, if the converter valve in the high-end valve hall of pole 1 is not unlocked or leakage current is not monitored, and the performance data of the equalizing electrode of the main cooling water pipe cannot be determined based on other converter valves in this pole, then the minimum performance data of the equalizing electrode of the main cooling water pipe of the high-end converter valve of pole 2 is used to evaluate the performance data of the equalizing electrode of the main cooling water pipe of the high-end converter valve of pole 1. The method for judging the performance data of the equalizing electrodes on the grounding side and the high-voltage side of the high-end of pole 2, the low end of pole 1, and the low end of pole 2 is the same as in the embodiment of the high-end of pole 1.

[0196] The system for real-time monitoring of the equalizing electrode of the high-pressure converter valve cooling water pipe is used to execute the method for real-time monitoring of the equalizing electrode of the high-pressure converter valve cooling water pipe as described above. Therefore, the real-time monitoring of the equalizing electrode of the high-pressure converter valve cooling water pipe will not be described again here.

[0197] This application provides a method and system for real-time monitoring of the equalizing electrodes of cooling water pipes. By monitoring the leakage current of the equalizing electrodes of the main cooling water pipes of the converter valves in real time and comparing the difference between the monitored leakage current and the theoretical value, the performance of the equalizing electrodes on the grounding side and high-pressure side of all converter valves can be obtained in real time. This replaces the traditional performance evaluation method of disassembling the equalizing electrodes to check the degree of scaling. The performance evaluation is more accurate and timely, and the workload of equalizing electrode maintenance is greatly reduced. Based on this, targeted maintenance strategies for equalizing electrodes can be formulated to achieve lean maintenance of equalizing electrodes.

[0198] It should be clearly understood that this application describes how specific examples are formed and used, but this application is not limited to any details of these examples. Rather, based on the teachings of the disclosure of this application, these principles can be applied to many other embodiments.

[0199] Furthermore, it should be noted that the above figures are merely illustrative representations of the processes included in the method according to exemplary embodiments of this application, and are not intended to be limiting. It is readily understood that the processes shown in the above figures do not indicate or limit the temporal order of these processes. Additionally, it is readily understood that these processes may be executed synchronously or asynchronously, for example, in multiple modules.

[0200] Exemplary embodiments of this application have been specifically shown and described above. It should be understood that this application is not limited to the detailed structures, arrangements, or implementation methods described herein; rather, this application is intended to cover various modifications and equivalent arrangements contained within the spirit and scope of the appended claims.

Claims

1. A method for real-time monitoring of the equalizing electrode of a cooling water pipe, characterized in that, The cooling water pipe serves as the main cooling water pipe for the converter valve, and the method includes: Real-time monitoring of the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve, the conductivity of the cooling water, the DC bus voltage of the converter valve, and the unlocking signal of the converter valve; The theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve is calculated based on the conductivity of the cooling water, the DC bus voltage of the converter valve, and the unlocking signal of the converter valve, and compared with the leakage current monitored in real time. The performance of the equalizing electrode of the main cooling water pipe of the converter valve is determined based on the comparison results and the unlocking signal of the converter valve.

2. The method as described in claim 1, characterized in that, The real-time monitoring includes the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve, the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal, including: The leakage current of each of the equalizing electrodes is monitored individually, or the leakage current of multiple electrodes in the equalizing electrodes is monitored in combination. The leakage current of the equalizing electrode on the ground side is monitored only, or the leakage current of both the equalizing electrode on the ground side and the equalizing electrode on the high voltage side is monitored. Leakage current monitoring can be performed on any one of the multiple converter valves with the same voltage to ground on the high-voltage side, or at least two of the multiple converter valves with the same voltage to ground on the high-voltage side.

3. The method as described in claim 1, characterized in that, The step of calculating the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the conductivity of the cooling water, the DC bus voltage of the converter valve, and the unlocking signal of the converter valve, and comparing it with the real-time monitored leakage current, includes: The average value of the theoretical leakage current of the equalizing electrode is calculated based on the conductivity of the cooling water, the DC bus voltage of the converter valve, and the unlocking signal of the converter valve. Extract the instantaneous value of the leakage current from the real-time monitored leakage current; The average value of the measured leakage current is calculated from the real-time monitored leakage current. The overcurrent multiple of the leakage current is calculated based on the average value of the theoretical leakage current and the instantaneous value of the leakage current; The attenuation coefficient of the leakage current is calculated based on the average value of the theoretical leakage current and the average value of the measured leakage current.

4. The method as described in claim 3, characterized in that, In calculating the average value of the theoretical leakage current of the equalizing electrode based on the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal, the average value of the theoretical leakage current is calculated according to the following formula: I L =K (σ) ×σ×S×(k×U) / L Among them, I L The average value of the theoretical leakage current flowing through the equalizing electrode, σ is the conductivity of the cooling water in the main cooling water pipe monitored in real time, and K is the average value of the leakage current flowing through the equalizing electrode. (σ) The ratio of the leakage current flowing through the equalizing electrode under the conductivity of the cooling water to the total leakage current of the main cooling water pipe is given by S, where S is the inner cross-sectional area of ​​the main cooling water pipe, L is the length of the main cooling water pipe, U is the average value of the DC bus voltage of the converter valve monitored in real time, and k is the ratio of the DC voltage of the high-voltage side of the main cooling water pipe to ground determined according to the unlocking signal of the converter valve to the DC bus voltage of the converter valve.

5. The method as described in claim 3, characterized in that, In calculating the overcurrent multiple of the leakage current based on the average value of the theoretical leakage current and the instantaneous value of the leakage current, the overcurrent multiple of the leakage current is calculated according to the following formula: b=I CS / I L ; Where b is the overcurrent multiple, I CS I represents the instantaneous value of the leakage current of the equalizing electrode as monitored in real time. L This is the average value of the theoretical leakage current flowing through the equalizing electrode.

6. The method as described in claim 3, characterized in that, In calculating the attenuation coefficient of the leakage current based on the average of the theoretical values ​​and the average of the measured values, the attenuation coefficient of the leakage current is calculated according to the following formula: a=I C / I L ; Where a is the attenuation coefficient, I C I is the average leakage current of the voltage equalization electrode as monitored in real time. L This is the average value of the theoretical leakage current flowing through the equalizing electrode.

7. The method as described in claim 1, characterized in that, The process of determining the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison results and the converter valve unlocking signal includes: Determine the performance of the grounding side equalization electrode of the main cooling water pipe of the converter valve; Determine the performance of the high-pressure side equalization electrode of the main cooling water pipe of the converter valve.

8. The method as described in claim 7, characterized in that, The process of determining the performance of the grounding side equalization electrode of the main cooling water pipe of the converter valve includes: Determine whether the converter valve corresponding to the grounding side equalizing electrode is unlocked; In response to the unlocking of the converter valve, it is determined whether to monitor the leakage current of the grounding side equalizing electrode; When monitoring the leakage current of the grounding side equalizing electrode, it is determined whether the overcurrent multiple of the leakage current of the grounding side equalizing electrode exceeds a first threshold. If the overcurrent multiple exceeds a first threshold, the cumulative number of times the overcurrent multiple exceeds the first threshold is counted, and it is determined whether the cumulative number of times reaches a first cumulative number. If the cumulative number of times reaches the first cumulative number of times, the performance of the grounding side equalizing electrode is evaluated as a failure.

9. The method as described in claim 8, characterized in that, The determination of the performance of the grounding side equalization electrode of the main cooling water pipe of the converter valve also includes: If the overcurrent multiple does not exceed the first threshold, determine whether the attenuation coefficient of the grounding side voltage equalization electrode is less than the second threshold. If the attenuation coefficient is less than the second threshold, the performance of the grounding side equalizing electrode is determined to be abnormal. If the attenuation coefficient is greater than or equal to the second threshold, the performance of the grounding side equalizing electrode is determined to be normal.

10. The method as described in claim 8, characterized in that, The determination of the performance of the grounding side equalization electrode of the main cooling water pipe of the converter valve also includes: Without monitoring the leakage current of the grounding side equalization electrode of the current converter valve, determine whether the performance of the grounding side equalization electrodes of multiple converter valves with the same voltage to ground and polarity as the current converter valve are all faulty or cannot be evaluated. In response to the fact that the performance of the grounding side equalization electrodes of the plurality of converter valves is not all faulty or unassessable, the performance of the current grounding side equalization electrode of the converter valve is determined to be the lowest performance among the performance of the grounding side equalization electrodes of the plurality of converter valves, wherein the lowest performance includes normal and abnormal, and the lowest performance is abnormal when the performance of the grounding side equalization electrodes of the plurality of converter valves includes normal and abnormal.

11. The method as described in claim 10, characterized in that, The determination of the performance of the grounding side equalization electrode of the main cooling water pipe of the converter valve also includes: In response to the fact that the converter valve is not unlocked or the performance of the grounding side equalization electrodes of the multiple converter valves is faulty or cannot be evaluated, it is determined whether the performance of the high-voltage side equalization electrodes of the multiple converter valves that have the same high-voltage side voltage to ground as the current converter valve but opposite polarity is faulty or cannot be evaluated. In response to the fact that the performance of the high-pressure side equalization electrodes of the plurality of converter valves is faulty or cannot be evaluated, it is determined that the performance of the ground side equalization electrode of the current converter valve is unevaluable. In response to the fact that the performance of the high-pressure side equalization electrodes of the plurality of converter valves is not all faulty or unassessable, the performance of the current ground side equalization electrode of the converter valve is determined to be the lowest performance among the performance of the high-pressure side equalization electrodes of the plurality of converter valves, wherein the lowest performance includes normal and abnormal, and the lowest performance is abnormal when the performance of the high-pressure side equalization electrodes of the plurality of converter valves includes normal and abnormal.

12. The method as described in claim 7, characterized in that, The process of determining the performance of the high-pressure side equalization electrode of the main cooling water pipe of the converter valve includes: Determine whether the converter valve corresponding to the high-voltage side equalizing electrode is unlocked; In response to the unlocking of the converter valve, it is determined whether to monitor the leakage current of the high-voltage side equalization electrode; While monitoring the leakage current of the high-voltage side equalizing electrode, it is determined whether the overcurrent multiple of the leakage current of the high-voltage side equalizing electrode exceeds a first threshold. If the overcurrent multiple exceeds a first threshold, the cumulative number of times the overcurrent multiple exceeds the first threshold is counted, and it is determined whether the cumulative number of times reaches a first cumulative number. If the cumulative number of times reaches the first cumulative number of times, the performance of the high-voltage side equalizing electrode is determined to be faulty.

13. The method as described in claim 12, characterized in that, The process of determining the performance of the high-pressure side equalization electrode of the main cooling water pipe of the converter valve also includes: If the overcurrent multiple does not exceed the first threshold, determine whether the attenuation coefficient of the high-voltage side equalizing electrode is less than the second threshold. If the attenuation coefficient is less than the second threshold, the performance of the high-voltage side equalizing electrode is determined to be abnormal. If the attenuation coefficient is greater than or equal to the second threshold, the performance of the high-voltage side equalizing electrode is determined to be normal.

14. The method as described in claim 12, characterized in that, The process of determining the performance of the high-pressure side equalization electrode of the main cooling water pipe of the converter valve also includes: Without monitoring the leakage current of the high-pressure side equalization electrode of the current converter valve, determine whether the performance of the high-pressure side equalization electrodes of multiple converter valves with the same voltage to ground and polarity as the current converter valve are all faulty or cannot be evaluated. In response to the fact that the performance of the high-pressure side equalization electrodes of the plurality of converter valves is not all faulty or unassessable, the performance of the current high-pressure side equalization electrode of the converter valve is determined to be the lowest performance among the performance of the high-pressure side equalization electrodes of the plurality of converter valves, wherein the lowest performance includes normal and abnormal, and the lowest performance is abnormal when the performance of the high-pressure side equalization electrodes of the plurality of converter valves includes normal and abnormal.

15. The method as described in claim 14, characterized in that, The process of determining the performance of the high-pressure side equalization electrode of the main cooling water pipe of the converter valve also includes: In response to the fact that the converter valve is not unlocked or the performance of the high-pressure side equalization electrodes of the multiple converter valves is faulty or cannot be evaluated, it is determined whether the performance of the grounding side equalization electrodes of the multiple converter valves that have the same high-pressure side voltage to ground but opposite polarity as the current converter valve is faulty or cannot be evaluated. In response to the fact that the performance of the grounding side equalization electrodes of the plurality of converter valves is faulty or cannot be evaluated, it is determined that the performance of the high-pressure side equalization electrode of the current converter valve is unevaluable. In response to the fact that the performance of the grounding side equalization electrodes of the plurality of converter valves is not all faulty or unassessable, the performance of the high-pressure side equalization electrode of the current converter valve is determined to be the lowest performance among the performance of the grounding side equalization electrodes of the plurality of converter valves, wherein the lowest performance includes normal and abnormal, and the lowest performance is abnormal when the performance of the grounding side equalization electrodes of the plurality of converter valves includes normal and abnormal.

16. A system for real-time monitoring of the equalizing electrode of a cooling water pipe, used to perform the method as described in any one of claims 1-15, characterized in that, include: A leakage current sensor is used to monitor the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve in real time. The DC monitoring subsystem is used to acquire the cooling water conductivity of the main cooling water pipe of the converter valve, the DC pole bus voltage of the converter valve, and the converter valve unlocking signal. An online leakage current monitoring device is connected to the leakage current sensor and the DC monitoring subsystem, respectively. It is used to receive the leakage current of the equalizing electrode sent by the leakage current sensor, and the cooling water conductivity of the main cooling water pipe of the converter valve, the DC bus voltage of the converter valve, and the converter valve unlocking signal sent by the DC monitoring subsystem. It is also used to calculate the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal, and compare it with the real-time monitored leakage current. Furthermore, it is used to determine the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison result and the converter valve unlocking signal. The leakage current online monitoring device is also used to receive the minimum performance of the equalizing electrode sent by multiple online leakage current monitoring devices on multiple converter valves with the same voltage to ground on the high-pressure side but opposite polarity as the current converter valve, in order to evaluate the performance of the equalizing electrode of the main cooling water pipe of the current converter valve.

17. A system for real-time monitoring of the equalizing electrode of a cooling water pipe, used to perform the method as described in any one of claims 1-15, characterized in that, include: A leakage current sensor is used to monitor the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve in real time. An online leakage current monitoring device is connected to the leakage current sensor and is used to receive the leakage current of the equalizing electrode sent by the leakage current sensor; The DC monitoring subsystem is used to acquire the cooling water conductivity of the main cooling water pipe of the converter valve, the DC pole bus voltage of the converter valve, and the converter valve unlocking signal. The intelligent evaluation subsystem is connected to the online leakage current monitoring device and the DC monitoring subsystem, respectively. It is used to receive the leakage current of the equalizing electrode sent by the leakage current sensor, and the cooling water conductivity of the main cooling water pipe of the converter valve, the DC bus voltage of the converter valve, and the unlocking signal of the converter valve sent by the DC monitoring subsystem. It is also used to calculate the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the cooling water conductivity, the DC bus voltage of the converter valve, and the unlocking signal of the converter valve, and compare it with the real-time monitored leakage current. It is also used to determine the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison result and the unlocking signal of the converter valve. The intelligent evaluation subsystem is also used to evaluate the performance of the equalization electrode of the main cooling water pipe of the current converter valve based on the lowest performance of the equalization electrodes of multiple converter valves that have the same voltage to ground on the high-pressure side but opposite polarity as the current converter valve.

18. A system for real-time monitoring of the equalizing electrode of a cooling water pipe, used to perform the method as described in any one of claims 1-15, characterized in that, include: A leakage current sensor is used to monitor the leakage current of the equalizing electrode of the main cooling water pipe flowing through the converter valve in real time. The DC monitoring subsystem is used to acquire the cooling water conductivity of the main cooling water pipe of the converter valve, the DC pole bus voltage of the converter valve, and the converter valve unlocking signal. An online leakage current monitoring device is connected to the leakage current sensor and the DC monitoring subsystem, respectively. It receives the leakage current of the equalizing electrode from the leakage current sensor, and the cooling water conductivity of the main cooling water pipe of the converter valve, the DC bus voltage of the converter valve, and the converter valve unlocking signal from the DC monitoring subsystem. It also calculates the theoretical value of the leakage current of the equalizing electrode of the main cooling water pipe of the converter valve based on the cooling water conductivity, the DC bus voltage of the converter valve, and the converter valve unlocking signal, and compares it with the real-time monitored leakage current. Furthermore, it determines the performance of the equalizing electrode of the main cooling water pipe of the converter valve based on the comparison result and the converter valve unlocking signal. The intelligent evaluation subsystem is used to receive the minimum performance of the equalizing electrode from multiple online leakage current monitoring devices on multiple converter valves that have the same voltage to ground on the high-pressure side of the current converter valve but opposite polarity, in order to evaluate the performance of the equalizing electrode of the main cooling water pipe of the current converter valve.

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