A method and system for evaluating the operating state of a converter valve and valve control

Abstract

The present application belongs to the technical field of direct current transmission, and particularly relates to a method and system for evaluating the operating state of a converter valve and a valve control. The present application sets evaluation factors corresponding to the operating state of the converter valve and the valve control, and obtains corresponding scores of the evaluation factors through fault state information and actual values of the evaluation factors representing the actual working conditions of each converter valve sub-module and valve control element, which can reflect the operating state of each aspect. Meanwhile, the overall operating state of the converter valve and the valve control is comprehensively reflected through corresponding scores of different evaluation factors and their proportion, the state level is determined, and the evaluation considers more comprehensive factors, which is more consistent with the actual operating condition, thereby improving the accuracy of the overall operating state evaluation of the converter valve. When the fault state information of the converter valve sub-module or the valve control element meets a specific fault condition, the operating state thereof is directly divided into a specific set state, otherwise the operating state is divided according to the score, so that specific fault conditions can be found in time and accurately.

Description

Technical Field

[0001] This invention belongs to the field of DC power transmission technology, specifically relating to a method and system for evaluating the operating status of converter valves and valve control. Background Technology

[0002] The intelligent analysis application for converter valves comprises two main parts: converter valve status analysis and converter valve diagnostic analysis. Taking the converter valve equipment as the core, it leverages status monitoring information, operational and maintenance information, and the design and manufacturing characteristics of the converter valve, while comprehensively considering family-related defects and historical fault records, to achieve functions such as converter valve status analysis and fault diagnosis. Through intelligent analysis of the converter valve system, it enables accurate determination of equipment status and intelligent diagnosis of equipment anomalies, effectively guiding the formulation of equipment operation and maintenance strategies, comprehensively supporting intelligent operation and maintenance, and improving the safety level of power grid equipment.

[0003] The converter valve status analysis has the following functions: it collects and connects information from valve control equipment to realize status monitoring and analysis of converter valves and valve control equipment, and equipment status assessment; based on the 3D model of the converter valve, it presents the status information of the whole and key components, including the corresponding status display of hidden dangers and defects of key components.

[0004] The converter valve diagnostic analysis has the following functions: for equipment that has failed, it can provide the cause of the failure, locate the failure, and propose maintenance and handling suggestions to generate a failure diagnosis and handling report; based on the 3D model of the converter valve, it can realize alarm data display and fault linkage display.

[0005] In the existing technology, the status analysis and diagnostic analysis of the converter valve mainly rely on the parameter data obtained by analyzing the status of each sub-module in the converter valve, as well as the judgment threshold corresponding to each parameter data, to judge the fault status of the converter valve sub-module and the converter valve as a whole. That is, the fault status of the converter valve as a whole is directly characterized by the fault status of each sub-module in the converter valve. The accuracy of the assessment of the fault status and operating status of the converter valve as a whole is low. Summary of the Invention

[0006] The purpose of this invention is to provide a method and system for evaluating the operating status of converter valves and valve control systems, in order to solve the problem that the existing methods for analyzing and diagnosing converter valve status have low accuracy in evaluating the overall fault condition and operating status of converter valves.

[0007] To achieve the above objectives, the present invention provides a method for evaluating the operating status of a converter valve and valve control, comprising the following steps:

[0008] Based on the actual values ​​of the evaluation factors for the operating status of the converter valve and valve control during operation, and their corresponding fault judgment conditions, the fault status information of each converter valve submodule and / or valve control element is obtained.

[0009] Based on the fault status information of each converter valve submodule and / or valve control element and the actual value of the evaluation factor, the score corresponding to each evaluation factor is obtained. Combining the proportion of each evaluation factor and the fault status information, the operating status of the converter valve and valve control is divided into states, and the state division result is used as the operating status evaluation result of the converter valve and valve control.

[0010] The beneficial effects of the above technical solution are as follows: Evaluation factors corresponding to the operating status of the converter valve and valve control are set, and corresponding scores for different evaluation factors are obtained through the actual operating conditions of each converter valve submodule and valve control element (i.e., fault status information and actual values ​​of evaluation factors). This allows for the reflection of various aspects of the operating status of the converter valve submodule and valve control element. Simultaneously, by considering the actual operating conditions, the corresponding scores of different evaluation factors, and their proportions, the overall operating status of the converter valve and valve control is comprehensively reflected, and its status level is determined. The factors considered during the evaluation are more comprehensive and more consistent with actual operating conditions, thereby eliminating potential safety hazards for operation monitoring, providing data support for daily maintenance, and improving the accuracy of the overall fault status and operating status assessment of the converter valve.

[0011] Furthermore, the operating states of the converter valve and valve control are classified by combining the scores corresponding to each evaluation factor with the proportion of each evaluation factor and the fault state information as follows:

[0012] If the fault status information of each converter valve submodule and / or valve control element meets the corresponding status judgment conditions, the operating status of the converter valve and / or valve control is directly classified into a specific set state; otherwise, a comprehensive score of the operating status of the converter valve and / or valve control is obtained based on the score corresponding to each evaluation factor and the proportion corresponding to each evaluation factor, and the operating status of the converter valve and / or valve control is classified into different set states based on the comprehensive score.

[0013] The beneficial effects of the above technical solution are: it can promptly and accurately detect relatively special fault conditions (usually more serious fault conditions or fault conditions that have a significant impact on the operating status of converter valves or valve control) and directly classify the status for special fault conditions, avoiding the reduced sensitivity to these special fault conditions caused by the comprehensive evaluation method of classifying the operating status through scoring and proportion, which affects the accuracy of the final evaluation results.

[0014] Furthermore, the evaluation factors for the operating status of the converter valve include: the voltage fluctuation range of the submodule, the switching frequency range, the capacitance value change, the IGBT junction temperature, and the number of submodule failures.

[0015] Furthermore, the evaluation factors for valve control operation status include: valve control board faults, valve control fiber optic alarm faults, valve control inter-communication fault counts, and valve control chip junction temperature.

[0016] Furthermore, the fault status information of each converter valve submodule and / or valve control element includes:

[0017] First fault status information: Percentage of converter valve submodules whose voltage fluctuation range exceeds the set fluctuation threshold;

[0018] Second fault status information: Percentage of converter valve sub-modules whose switching frequency range exceeds the set frequency threshold;

[0019] Third fault status information: Percentage of converter valve submodules whose capacitance value changes greater than the set change threshold;

[0020] Fourth fault status information: The percentage of converter valve submodules whose average junction temperature of IGBTs exceeds the first set temperature threshold within a corresponding set time period during charging and unlocking operation.

[0021] The scoring methods for each evaluation factor, based on the fault status information of each converter valve submodule and / or valve control element and the actual values ​​of the evaluation factors, include:

[0022] If the first fault status information is less than or equal to the first set ratio threshold, the score of the voltage fluctuation range of the submodule is set to the corresponding fixed score; otherwise, the score of the voltage fluctuation range of the submodule is obtained based on the difference between the first fault status information and the first set quantity threshold and the corresponding fixed score.

[0023] If the second fault status information is less than or equal to the second set ratio threshold, the score of the switching frequency range of the submodule is set to the corresponding fixed score; otherwise, the score of the switching frequency range of the submodule is obtained based on the difference between the second fault status information and the second set quantity threshold and the corresponding fixed score.

[0024] If the third fault status information is less than or equal to the third set ratio threshold, the score for the change in capacitance value of the submodule is set to the corresponding fixed score; otherwise, the score for the change in capacitance value of the submodule is obtained based on the difference between the third fault status information and the third set quantity threshold and the corresponding fixed score.

[0025] If the fourth fault status information is less than or equal to the fourth set ratio threshold, the score of the IGBT junction temperature of the submodule is set to the corresponding fixed score; otherwise, the score of the IGBT junction temperature of the submodule is obtained based on the difference between the fourth fault status information and the fourth set quantity threshold and the corresponding fixed score.

[0026] The score for the number of submodule failures is obtained based on the actual value of the number of submodule failures, the corresponding fixed score, and the redundancy of the single-bridge arm submodule.

[0027] Furthermore, the fault status information of each converter valve submodule and / or valve control element includes: the number of pulse board faults and redundant communication faults in valve control board faults, the number of alarm fibers in valve control fiber optic alarm faults, the change of each communication fault count in the valve control internal communication channel in valve control inter-communication fault count, and the number of valve control chips whose average junction temperature exceeds the second set temperature threshold within the corresponding set time.

[0028] The scoring methods for each evaluation factor, based on the fault status information of each converter valve submodule and / or valve control element and the actual values ​​of the evaluation factors, include:

[0029] The valve control board fault score is obtained based on the number of pulse board faults, the number of redundant communication faults, and the corresponding set scores in the valve control board faults.

[0030] The score for the valve-controlled fiber optic alarm fault is obtained based on the number of alarm fibers in the valve-controlled fiber optic alarm fault and the corresponding set score.

[0031] The corresponding channel score is obtained by calculating the changes in the communication fault counts of each communication channel within the valve control system. The score for the inter-valve communication fault count is obtained by combining the channel scores with the corresponding set scores.

[0032] The valve-controlled chip junction temperature score is obtained based on the number of valve-controlled chips whose average junction temperature exceeds the second set temperature threshold within a corresponding set time period and the corresponding set score.

[0033] Furthermore, the set state is divided into healthy, sub-healthy, poor, and severe states.

[0034] Furthermore, the fault status information of each converter valve submodule and / or valve control element includes the number of faults in the converter valve submodule;

[0035] If the fault status information of each converter valve submodule and / or valve control element meets the corresponding status judgment conditions, the methods for directly classifying the operating status of the converter valve and / or valve control into a specific set state include:

[0036] If the condition for judging the state that the number of faults in the converter valve submodule of a single bridge arm exceeds the corresponding redundancy number is met, the operating state of the converter valve will be classified as a severe state.

[0037] If the condition that the total number of faults in the converter valve submodule exceeds the corresponding redundancy number is met, the converter valve operating status will be classified as a critical state.

[0038] Furthermore, the fault status information of each converter valve submodule and / or valve control element also includes the judgment results of whether the self-test of the dual-set and single-set valve control is abnormal;

[0039] If the fault status information of each converter valve submodule and / or valve control element meets the corresponding status judgment conditions, the method of directly classifying the operating status of the converter valve and / or valve control into a specific set state also includes:

[0040] If the conditions for judging the abnormality of the valve control dual self-test are met, the valve control operation status will be classified as a severe state.

[0041] If the conditions for judging the abnormality of the valve control unit's self-test are met, the valve control operating status will be classified as a poor state.

[0042] The present invention also provides an operational status evaluation system for converter valves and valve control systems, including a processor, which is used to execute program instructions to implement the operational status evaluation method for converter valves and valve control systems as described above.

[0043] The operating status assessment system for converter valves and valve control systems can achieve the same beneficial effects as the aforementioned operating status assessment method for converter valves and valve control systems. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the flexible DC transmission system to which the operational status evaluation method for the converter valve and valve control of the present invention is applied in an embodiment of the operational status evaluation method for the converter valve and valve control of the present invention.

[0045] Figure 2 This is a flowchart illustrating the method for evaluating the operating status of a converter valve and its control system, as described in an embodiment of the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0047] Example of an operational status assessment method for converter valves and valve control systems

[0048] This embodiment presents a technical solution for evaluating the operating status of a converter valve and its control system, applicable to applications such as... Figure 1 The flexible DC transmission system shown; reference Figure 2 It includes the following steps:

[0049] 1) Based on the actual values ​​of the evaluation factors of the operating status of the converter valve and valve control during operation and their corresponding fault judgment conditions, obtain the fault status information of each converter valve sub-module and valve control element;

[0050] First, the evaluation factors and fault status information of the converter valve operating status are analyzed. In this embodiment, the evaluation factors of the converter valve operating status include: the voltage fluctuation range of the submodule, the switching frequency range, the capacitance value change, the IGBT junction temperature, and the number of submodule faults; the evaluation factors of the valve control operating status include: valve control board faults, valve control fiber optic alarm faults, valve control inter-communication fault counts, and valve control chip junction temperature.

[0051] The fault status information for each converter valve submodule and valve control element includes (i.e., the fault status information for each converter valve submodule):

[0052] The first fault status information is the percentage of converter valve sub-modules whose voltage fluctuation range exceeds the set fluctuation threshold.

[0053] The second fault status information is the percentage of converter valve sub-modules whose switching frequency range is greater than the set frequency threshold.

[0054] The third fault status information is the percentage of converter valve sub-modules whose capacitance value changes more than the set change threshold.

[0055] The fourth fault status information is the percentage of converter valve submodules whose average junction temperature of IGBTs exceeds the first set temperature threshold within a set time period during charging and unlocking operation.

[0056] Therefore, based on the actual values ​​of each evaluation factor and its corresponding fault judgment conditions, the specific methods for obtaining the fault status information of each converter valve submodule and valve control element include:

[0057] ① During unlocking operation, voltage fluctuation analysis is performed. A sampling period is set (e.g., valve control operation period, 50us). The maximum, minimum, and average voltage of all converter valve submodules are calculated within the corresponding time period (within 1s in this embodiment), as well as the percentage of the difference between the maximum and minimum voltages of all converter valve submodules relative to the average value. Then, the average value of this percentage is calculated within a specific time period (within 1min in this embodiment), and the number of converter valve submodules whose average value of this percentage exceeds the set fluctuation threshold (e.g., 10%) is calculated. The proportion of the number of converter valve submodules whose average value of this percentage exceeds the set fluctuation threshold to the total number of converter valve submodules is taken as the proportion of the number of converter valve submodules whose voltage fluctuation range is greater than the set fluctuation threshold.

[0058] ② During the unlocking operation, the switching frequency of each converter valve submodule is calculated within the corresponding time (within 1 second in this embodiment) based on the IGBT on / off state. The percentage of converter valve submodules with switching frequencies less than the set frequency threshold (200Hz in this embodiment) is counted. For converter valve submodules whose switching frequencies are greater than the set frequency threshold for a continuous set duration (e.g., 10 minutes), a switching frequency alarm message is output. Furthermore, the proportion of converter valve submodules whose switching frequencies are greater than the set frequency threshold for a continuous set duration to the total number of converter valve submodules is taken as the percentage of converter valve submodules whose switching frequencies are greater than the set frequency threshold.

[0059] ③ During the unlocking operation, according to the calculation method of the converter valve capacitor value, each converter valve submodule outputs an average capacitance value every 1 second, and then calculates the average value of all capacitance values ​​within 1 hour, and outputs the module capacitance value corresponding to one converter valve submodule every 1 hour; calculates the number of converter valve submodules whose module capacitance value changes from the factory measurement value (i.e., capacitance value deviation) is greater than the set change threshold (5% in this embodiment). For converter valve submodules whose capacitance value deviation is greater than the set change threshold for a set time (1 day in this embodiment), capacitance value alarm information is output. Furthermore, the proportion of the number of these converter valve submodules to the total number of converter valve submodules is used as the proportion of the number of converter valve submodules whose capacitance value changes are greater than the set change threshold.

[0060] ④ During charging and unlocking operation, perform IGBT junction temperature analysis, calculate the average junction temperature of IGBTs in each converter valve submodule within a set time (10 min in this embodiment), and the number of converter valve submodules whose average junction temperature exceeds the first set temperature threshold (50 °C in this embodiment). The proportion of the number of such converter valve submodules to the total number of converter valve submodules is used as the percentage of the number of converter valve submodules whose average junction temperature exceeds the first set temperature threshold within the set time during charging and unlocking operation.

[0061] During charging and unlocking operation, if the converter valve submodule experiences a fault that prevents it from operating normally, such as power failure, IGBT drive failure, overvoltage, undervoltage, or valve control communication failure, the submodule fault count will be incremented by 1.

[0062] Then, the evaluation factors and fault status information of the valve control operation status are analyzed. In this embodiment, the fault status information of each converter valve submodule and valve control element also includes (i.e., the fault status information of each valve control element): the number of pulse board faults and redundant communication faults in the valve control board faults, the number of alarm fibers in the valve control fiber optic alarm faults, the change of each communication fault count in the valve control internal communication channel in the valve control inter-communication fault count, and the number of valve control chips whose average junction temperature exceeds the second set temperature threshold within the corresponding set time.

[0063] The methods for obtaining the number of pulse board faults and redundant communication faults in valve control board faults, the number of alarm fibers in valve control fiber optic alarm faults, and the changes in the communication fault counts of each communication channel in the valve control inter-communication fault count are all existing technologies and will not be elaborated here. The junction temperature of the valve control chip is calculated, and the average junction temperature of each valve control chip within a set time (10 min in this embodiment) is calculated, as well as the number of chips whose average junction temperature exceeds the second set temperature threshold (50 °C in this embodiment). The number of chips is taken as the number of valve control chips whose average junction temperature exceeds the second set temperature threshold within the corresponding set time.

[0064] 2) Based on the fault status information of each converter valve submodule and valve control element and the actual value of the evaluation factor, obtain the score corresponding to each evaluation factor. Combine the proportion of each evaluation factor and the fault status information of each converter valve submodule and valve control element, classify the operating status of the converter valve and valve control respectively, and use the state classification result as the operating status evaluation result of the converter valve and valve control.

[0065] The method for classifying the operating status of converter valves and valve control components is as follows: if the fault status information of each converter valve submodule or valve control element meets the corresponding status judgment condition, the operating status of the converter valve or valve control is directly classified into a specific set state; otherwise, a comprehensive score for the operating status of the converter valve or valve control is obtained based on the score corresponding to each evaluation factor and the proportion corresponding to each evaluation factor, and the operating status of the converter valve or valve control is classified into different set states based on the comprehensive score. In this embodiment, the full score (i.e., the fixed score corresponding to the evaluation factor mentioned below) of all evaluation factors of the converter valve is 100 points, and the score of each evaluation factor is multiplied by different proportions and then added together to obtain the final comprehensive score; in other embodiments, the fixed scores corresponding to the evaluation factors may also be different.

[0066] In this embodiment, the set states of the converter valve are divided into healthy, sub-healthy, poor, and severe states. A healthy state indicates that the converter valve is operating normally with no deterioration trend; a sub-healthy state indicates that the converter valve is operating safely with no obvious deterioration trend; a poor state indicates that the converter valve is operating poorly with some degree of deterioration; and a severe state indicates that the converter valve can no longer operate safely and has severely deteriorated. Therefore, the specific methods for obtaining the scores corresponding to each evaluation factor and classifying the operating state of the converter valve include the following:

[0067] If the first fault status information is less than or equal to the first set percentage threshold, the voltage fluctuation range score of the submodule is set to the corresponding fixed score; otherwise, the voltage fluctuation range score of the submodule is obtained based on the difference between the first fault status information and the first set quantity threshold and the corresponding fixed score. Specifically, referring to Table 1, in this embodiment, during the unlocking operation, if the number of modules with a voltage fluctuation range (the percentage average of voltage within 1 minute) greater than 10% corresponding to the first fault status information is less than or equal to the first set percentage threshold (20% in this embodiment), the voltage fluctuation range score of the submodule is set to full score; otherwise, it is calculated according to the corresponding formula in Table 1.

[0068] Table 1

[0069]

[0070] Here, a1% refers to the value of the first fault status information.

[0071] If the second fault status information is less than or equal to the second set proportion threshold, the score for the switching frequency range of the submodule is set to the corresponding fixed score; otherwise, the score for the switching frequency range of the submodule is obtained based on the difference between the second fault status information and the second set quantity threshold, and the corresponding fixed score. Specifically, referring to Table 2, during the unlocking operation, if the number of submodules with a switching frequency greater than 200Hz and lasting for 10 minutes is less than or equal to the second set proportion threshold (20% in this embodiment), the score for the switching frequency range of the submodule is set to full score; otherwise, it is calculated according to the corresponding formula in Table 2.

[0072] Table 2

[0073]

[0074] Here, a2% refers to the value of the second fault status information.

[0075] If the third fault status information is less than or equal to the third set proportion threshold, the score for the change in capacitance value of the submodule is set to the corresponding fixed score; otherwise, the score for the change in capacitance value of the submodule is obtained based on the difference between the third fault status information and the third set quantity threshold and the corresponding fixed score. Specifically, referring to Table 3, during the unlocking operation, if the number of submodules with capacitance value deviation greater than 5% is less than or equal to the third set proportion threshold (20% in this embodiment), the score for the change in capacitance value of the submodule is set to full score; otherwise, it is calculated according to the corresponding formula in Table 3.

[0076] Table 3

[0077]

[0078] Here, a3% refers to the value of the third fault status information.

[0079] If the fourth fault status information is less than or equal to the fourth set proportional threshold, the IGBT junction temperature score of the submodule is set to the corresponding fixed score; otherwise, the IGBT junction temperature score of the submodule is obtained based on the difference between the fourth fault status information and the fourth set quantity threshold and the corresponding fixed score. Specifically, referring to Table 4, if the number of submodules whose average junction temperature exceeds the first set temperature threshold (50℃) within 10 minutes during charging and unlocking operation is less than or equal to 20%, the IGBT junction temperature score of the submodule is set to full score; otherwise, it is calculated according to the following formula:

[0080] Table 4

[0081]

[0082] Here, a4% refers to the value of the fourth fault status information.

[0083] The score for the number of submodule failures is obtained based on the actual number of submodule failures, the corresponding fixed score, and the redundancy of the single-bridge arm submodule. Specifically, based on the full score, for each additional submodule failure, the score for the number of submodule failures increases by M, where M = (100 / 6) / N, that is, the value of M is the result of dividing 100 by 6 and then dividing by N, where N is the redundancy of the single-bridge arm. The value of N usually ranges from a few to several dozen, depending on the number of single-bridge arm submodules, and is generally about 8% of the number of single-bridge arm submodules.

[0084] Finally, based on the scores p corresponding to each evaluation factor... i and the proportion z i Calculate the overall score The final status assessment result of the converter valve is output based on the comprehensive score: healthy / sub-healthy / poor / severe (a comprehensive score of 80-100 is healthy, 70-80 is sub-healthy, 50-70 is poor, and below 50 is severe). An example of the comprehensive score for the converter valve's operating status is shown in Table 5 below:

[0085] Table 5

[0086] 1 Voltage fluctuation range of submodule 99 20％ 2 Submodule switching frequency range 95 20％ 3 Capacitor value change in submodule 95 10％ 4 IGBT junction temperature variation in submodule 95 10％ 5 Number of module failures in a submodule 98 40％ Overall score 97

[0087] In this embodiment, the fault status information of each converter valve submodule and valve control element also includes the number of faults in the converter valve submodule; if the fault status information of each converter valve submodule and valve control element meets the corresponding status judgment condition, the way to directly classify the operating status of the converter valve and valve control into a specific set state includes:

[0088] If the condition that the number of faults in a single bridge arm converter valve submodule exceeds the corresponding redundancy number is met, the converter valve operating state is classified as a critical state; if the condition that the total number of faults in a converter valve submodule exceeds the corresponding redundancy number is met, the converter valve operating state is classified as a critical state.

[0089] In this embodiment, the set state corresponding to the valve control is also divided into healthy, sub-healthy, poor, and severe states. A healthy state indicates that the valve control is operating normally with no deterioration trend; a sub-healthy state indicates that the valve control is operating safely with no obvious deterioration trend; a poor state indicates that the valve control is operating poorly with a certain degree of deterioration; and a severe state indicates that the valve control can no longer operate safely and has severely deteriorated. All evaluation factors for the valve control have a maximum score of 100 points (i.e., the set scores corresponding to the evaluation factors mentioned below). The scores of each evaluation factor are multiplied by different proportions and then added together to obtain the final comprehensive score. In other embodiments, the fixed scores corresponding to the evaluation factors may also be different. Therefore, the specific methods for obtaining the scores corresponding to each evaluation factor and classifying the operating state of the valve control include the following:

[0090] a) Based on the number of pulse board failures, the number of redundant communication failures, and the corresponding set scores in the valve control board failures, a score for the valve control board failure is obtained.

[0091] Valve control board failure refers to a type of failure where no system switchover occurs after a communication failure between boards. Specifically, it refers to a pulse board failure in the pulse distribution chassis or a communication failure between boards with cross-redundant communication. The relationship between the number of pulse board (i.e., LER board) failures, the number of redundant communication failures, and the corresponding set scores in valve control board failures and the valve control board failure score is shown in Table 6 below. The single-bridge arm LER board redundancy data refers to the maximum number of LER board failures that a single bridge arm can tolerate. Under this number of failures, valve control can continue to operate normally without switching.

[0092] Table 6

[0093]

[0094]

[0095] b) Based on the number of alarm fibers in the valve-controlled fiber optic alarm fault and the corresponding set score, the score of the valve-controlled fiber optic alarm fault is obtained; in this embodiment, the deduction value increases by 100 / NA for each additional alarm fiber fault, where NA is the number of valve-controlled fibers).

[0096] c) Obtain the corresponding channel score based on the changes in the communication fault counts of each internal communication channel of the valve control system. Combine the channel scores with the corresponding set scores to obtain the score for the inter-valve communication fault count. Specifically, the deduction value (referred to as the channel score) corresponding to the communication fault count of each internal communication channel of the valve control system is 100 / NT, where NT is the total number of internal communication channels of the valve control system. If the change in the communication fault count of a certain communication channel of the valve control system is greater than the set number of changes, then the channel score is deducted. If the fault occurs within a set time (one day in this embodiment) after the deduction, the score is further reduced. If the fault count remains unchanged, the communication channel is considered to have returned to normal, and the channel score is added back. For example, if the total number of communication channels within a valve control system is 50, the channel score is (100 / 50) = 2 points. If the communication fault count for a certain communication channel increases by more than 10, one channel score is deducted from the valve control system's communication fault count score, i.e., 2 points are deducted. If the communication fault count for that channel does not increase (remain unchanged) for 24 consecutive hours in the following period, the communication channel is considered to have returned to normal, and the valve control system's communication fault count score is added back to the channel score, i.e., 2 points are added back.

[0097] d) Based on the number of valve control chips whose average junction temperature exceeds the second set temperature threshold within the corresponding set time and the corresponding set score, the score of the valve control chip junction temperature is obtained; specifically, the average junction temperature of each valve control chip within the corresponding set time (10 min in this embodiment) and the number of valve control chips whose average junction temperature exceeds the second set temperature threshold (50°C) are calculated. When all valve control chip junction temperatures are less than the alarm value, the score is full. For each additional valve control chip whose junction temperature exceeds the alarm value (i.e., the second set temperature threshold), 100 / NX points are deducted, where NX is the total number of valve control chips.

[0098] In addition, the fault status information of each converter valve submodule and valve control element also includes the judgment results of whether the self-test of the dual-set and single-set valve control is abnormal; if the fault status information of each converter valve submodule and valve control element meets the corresponding status judgment conditions, the method of directly classifying the operating status of the converter valve and valve control into a specific set state also includes:

[0099] If the conditions for judging the abnormality of the self-test of the two valve control systems are met, the valve control operation status is classified as a severe state; if the conditions for judging the abnormality of the self-test of the single valve control system are met, the valve control operation status is classified as a poor state; in other cases, the status is classified according to the comprehensive score.

[0100] Finally, based on the scores p corresponding to each evaluation factor... i and the proportion z i Calculate the overall score The final status assessment result of the valve control is output based on the comprehensive score: Healthy / Sub-healthy / Poor / Severe (a comprehensive score of 80-100 is Healthy, 70-80 is Sub-healthy, 50-70 is Poor, and below 50 is Severe). An example of the comprehensive score for the valve control's operating status is shown in Table 7 below.

[0101] Table 7

[0102] 1 Valve control board failure 99 40％ 2 Valve-controlled fiber optic alarm fault 95 20％ 3 Valve-controlled inter-communication fault count 95 20％ 4 Valve-controlled chip junction temperature 96 20％ Overall score 97

[0103] Therefore, the method for evaluating the operating status of the converter valve and valve control in this embodiment can not only understand the operating status of a single converter valve submodule, but also comprehensively reflect the overall operating status of the converter valve and valve control by considering the operating conditions of the converter valve submodule and valve control in various aspects, and determine its status level. The evaluation considers more comprehensive factors and is more in line with actual operating conditions, thereby eliminating safety hazards for operation monitoring and providing data support for daily maintenance.

[0104] Example of an operational status assessment system for converter valves and valve control

[0105] This embodiment provides a technical solution for an operational status evaluation system for converter valves and valve control systems, including a processor for executing program instructions to implement the operational status evaluation method for converter valves and valve control systems as described in the above embodiment.

[0106] Since the working process and working principle of the operating status evaluation system in this embodiment have been described in detail in the above embodiment of the operating status evaluation method for converter valves and valve control, they will not be repeated here.

[0107] This invention has the following characteristics:

[0108] 1) Set evaluation factors corresponding to the operating status of converter valves and valve control components, and obtain corresponding scores for different evaluation factors through the actual operating conditions of each converter valve sub-module and valve control component (i.e., fault status information and actual values ​​of evaluation factors). This can reflect the operating status of converter valve sub-modules and valve control components in various aspects. At the same time, by combining the actual operating conditions, the corresponding scores of different evaluation factors and their proportions, the overall operating status of converter valves and valve control is comprehensively reflected, and their status levels are determined. The factors considered during the evaluation are more comprehensive and more in line with the actual operating conditions, thereby eliminating safety hazards for operation monitoring, providing data support for daily maintenance, and improving the accuracy of the overall fault status and operating status assessment of converter valves.

[0109] 2) When the fault condition (i.e., fault status information) of the converter valve submodule or valve control element meets specific fault conditions, the operating status of the converter valve or valve control is directly classified into a specific set state. Otherwise, the operating status of the converter valve or valve control is classified according to the score. This can promptly and accurately identify more special fault conditions (usually more serious fault conditions or fault conditions that have a greater impact on the operating status of the converter valve or valve control), avoiding the reduced sensitivity to these special fault conditions caused by the comprehensive evaluation method of classifying the operating status by score and proportion, which affects the accuracy of the final evaluation results.

[0110] It should be understood that the above-described specific embodiments of the present invention are merely illustrative or explanatory of the principles of the present invention, and do not constitute a limitation thereof.

Claims

1. A method for evaluating the operating status of a converter valve and valve control, characterized in that, Includes the following steps: Based on the actual values ​​of the evaluation factors for the operating status of the converter valve and valve control during operation, and their corresponding fault judgment conditions, the fault status information of each converter valve submodule and valve control element is obtained. Based on the fault status information of each converter valve submodule and valve control element and the actual value of the evaluation factor, the score corresponding to each evaluation factor is obtained. Combined with the proportion of each evaluation factor and the fault status information, the operating status of the converter valve and valve control is divided into states respectively. The state division result is used as the operating status evaluation result of the converter valve and valve control. Evaluation factors for the operating status of the converter valve include: voltage fluctuation range of the submodule, switching frequency range, capacitance value change, IGBT junction temperature, and number of submodule failures; The fault status information of each converter valve submodule includes: First fault status information: Percentage of converter valve submodules whose voltage fluctuation range exceeds the set fluctuation threshold; Second fault status information: Percentage of converter valve sub-modules whose switching frequency range exceeds the set frequency threshold; Third fault status information: Percentage of converter valve submodules whose capacitance value changes greater than the set change threshold; Fourth fault status information: The percentage of converter valve submodules whose average junction temperature of IGBTs exceeds the first set temperature threshold within a corresponding set time period during charging and unlocking operation. Based on the fault status information of each converter valve submodule and the actual values ​​of the evaluation factors, the scoring methods for each evaluation factor are as follows: If a certain fault status information is less than or equal to the corresponding set ratio threshold, the score of the evaluation factor corresponding to the fault status information of the submodule is set to the corresponding fixed score; otherwise, the score of the evaluation factor corresponding to the fault status information of the submodule is obtained based on the difference between the fault status information and the corresponding set ratio threshold and the corresponding fixed score. The score for the number of submodule failures is obtained based on the actual value of the number of submodule failures, the corresponding fixed score, and the redundancy of the single-bridge arm submodule.

2. The method for evaluating the operating status of the converter valve and valve control according to claim 1, characterized in that, The operating states of the converter valve and valve control are classified by combining the scores corresponding to each evaluation factor with the proportion of each evaluation factor and the fault status information as follows: If the fault status information of each converter valve submodule and / or valve control element meets the corresponding status judgment conditions, the operating status of the converter valve and / or valve control is directly classified into a specific set state. Otherwise, based on the scores corresponding to each evaluation factor and the proportion corresponding to each evaluation factor, a comprehensive score is obtained for the operating status of the converter valve and / or valve control, and the operating status of the converter valve and / or valve control is divided into different setting states based on the comprehensive score.

3. The method for evaluating the operating status of the converter valve and valve control according to claim 2, characterized in that, The set states are divided into healthy, sub-healthy, poor, and severe states.

4. The method for evaluating the operating status of the converter valve and valve control according to claim 2, characterized in that, Evaluation factors for valve control operation status include: valve control board faults, valve control fiber optic alarm faults, valve control inter-communication fault counts, and valve control chip junction temperature.

5. The method for evaluating the operating status of the converter valve and valve control according to claim 3, characterized in that, The health status refers to the valve control operating normally with no deterioration trend; Sub-healthy state refers to the valve control operating safely with no obvious deterioration trend; poor state refers to the valve control operating poorly with a certain degree of deterioration. A critical condition indicates that the valve control system is no longer able to operate safely and has deteriorated significantly.

6. The method for evaluating the operating status of the converter valve and valve control according to claim 4, characterized in that, The fault status information of the valve control element includes: the number of pulse board faults and redundant communication faults in the valve control board faults, the number of alarm fibers in the valve control fiber optic alarm faults, the changes in the count of each communication fault in the valve control internal communication channel in the valve control inter-communication fault count, and the number of valve control chips whose average junction temperature exceeds the second set temperature threshold within the corresponding set time.

7. The method for evaluating the operating status of the converter valve and valve control according to claim 6, characterized in that, The methods for obtaining scores for each evaluation factor based on the fault status information of the valve-controlled element and the actual values ​​of the evaluation factors include: The valve control board fault score is obtained based on the number of pulse board faults, the number of redundant communication faults, and the corresponding set scores in the valve control board faults. The score for the valve-controlled fiber optic alarm fault is obtained based on the number of alarm fibers in the valve-controlled fiber optic alarm fault and the corresponding set score. The corresponding channel score is obtained by counting the changes in the communication faults of each communication channel within the valve control system. The score of the inter-valve communication fault count is obtained by combining the channel score and the corresponding set score. The score of the valve control chip junction temperature is obtained by counting the number of valve control chips whose average junction temperature exceeds the second set temperature threshold within the corresponding set time and the corresponding set score.

8. The method for evaluating the operating status of the converter valve and valve control according to claim 3, characterized in that, The fault status information of each converter valve submodule and / or valve control element includes the number of faults in the converter valve submodule; If the fault status information of each converter valve submodule and / or valve control element meets the corresponding status judgment conditions, the methods for directly classifying the operating status of the converter valve and / or valve control into a specific set state include: If the condition for judging the state that the number of faults in the converter valve submodule of a single bridge arm exceeds the corresponding redundancy number is met, the operating state of the converter valve will be classified as a severe state. If the condition that the total number of faults in the converter valve submodule exceeds the corresponding redundancy number is met, the converter valve operating status will be classified as a critical state.

9. The method for evaluating the operating status of the converter valve and valve control according to claim 8, characterized in that, The fault status information of each converter valve submodule and / or valve control element also includes the judgment results of whether the self-test of the dual-set and single-set valve control is abnormal; If the fault status information of each converter valve submodule and / or valve control element meets the corresponding status judgment conditions, the method of directly classifying the operating status of the converter valve and / or valve control into a specific set state also includes: If the conditions for judging the abnormality of the valve control dual self-test are met, the valve control operation status will be classified as a severe state. If the conditions for judging the abnormality of the valve control unit's self-test are met, the valve control operating status will be classified as a poor state.

10. A system for evaluating the operational status of a converter valve and its control, characterized in that, Includes a processor for executing program instructions to implement the method for evaluating the operating status of the converter valve and valve control as described in any one of claims 1-9.

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