A method and system for harmonic detection for a transformer

Abstract

The application provides a harmonic detection method and system for a transformer, and belongs to the technical field of harmonic detection. The method specifically comprises the following steps: determining abnormal variation conditions of temperature monitoring data of temperature monitoring devices in different converter bridges based on the temperature monitoring data; determining abnormal monitoring devices in the temperature monitoring devices according to the abnormal variation conditions; determining the distribution data of the abnormal monitoring devices in the different converter bridges; combining variation conditions of operating voltages of thyristors in the different converter bridges in different operating current intervals; determining that the monitoring reliability of the converter meets the requirements; determining deviation conditions of the temperature monitoring data between the thyristors in the different converter bridges in the different operating current intervals; and determining the harmonic detection method of the transformer in the different operating current intervals, so that the accuracy of the harmonic detection processing is improved.

Description

Technical Field

[0001] This invention belongs to the field of harmonic detection technology, specifically relating to a harmonic detection method and system for transformers. Background Technology

[0002] Transformers inevitably generate harmonics during operation. Excessive harmonics can affect the operation of electrical equipment. Therefore, how to detect and promptly address harmonics in transformers has become an urgent technical problem to be solved.

[0003] Existing technical solutions often utilize harmonic detection equipment installed on the transformer for harmonic detection and analysis. However, for DC converter transformers, the goal is to convert AC power into the commutation voltage required by the converter. Excessive harmonics can affect the operating status of the converter's thyristors. Therefore, determining the transformer's harmonic detection method based on the converter's operating status and reducing the impact of harmonics on the converter's thyristor operating status has become an urgent technical problem to be solved.

[0004] Therefore, in order to solve the above-mentioned technical problems, this application provides a harmonic detection method and system for transformers. Summary of the Invention

[0005] To achieve the objectives of this invention, the following technical solution is adopted:

[0006] To achieve the above-mentioned objectives, this application provides a harmonic detection method for transformers, comprising the following:

[0007] S1 determines the converter failure data based on the converter's operating data, and when the converter's operating status meets the requirements based on the converter failure data, determines the temperature monitoring data in different converter bridges of the converter.

[0008] S2 determines the abnormal changes in the temperature monitoring data of different converter bridges based on the temperature monitoring data, and determines the abnormal monitoring devices among the temperature monitoring devices based on the abnormal changes.

[0009] S3 uses the distribution data of abnormal monitoring devices in different converter bridges, combined with the variation of operating voltage of thyristors in different converter bridges in different operating current ranges, to determine that when the monitoring reliability of the converter meets the requirements, the deviation of temperature monitoring data between thyristors in different converter bridges in different operating current ranges is used to determine the harmonic detection method of the transformer in different operating current ranges.

[0010] The beneficial effects of this invention are as follows:

[0011] By using the distribution data of abnormal monitoring devices in different converter bridges and the variation of operating voltage of thyristors in different converter bridges in different operating current ranges, it is determined whether the monitoring reliability of the converter meets the requirements. Considering the differences in the consistency of the operating characteristics of thyristors in different converter bridges due to the differences in the variation of operating voltage in different operating current ranges, and further considering the differences in the requirements for temperature monitoring reliability due to the differences in consistency, and further combining the distribution data of abnormal monitoring devices, a reliable assessment of the monitoring reliability of the converter is achieved, which also lays the foundation for generating differentiated harmonic detection methods based on the differences in monitoring reliability.

[0012] By analyzing the deviations in temperature monitoring data between thyristors in different converter bridges within different operating current ranges, a harmonic detection method for transformers in different operating current ranges is determined. This fully considers the risks of inconsistent thyristor temperature distributions caused by deviations in temperature monitoring data between thyristors under different harmonic conditions. Consequently, it achieves the desired accuracy and meets the different requirements for anomaly standards in harmonic detection across different operating current ranges based on the aforementioned data. While ensuring the efficiency of harmonic detection, it also guarantees the accuracy of anomaly identification and processing, and simultaneously ensures the operational reliability of the converter.

[0013] A further technical solution is that the converter failure data includes the number of converter failures.

[0014] A further technical solution involves determining that the operating state of the converter meets the requirements, specifically including:

[0015] The number of commutation failures of the converter is determined based on the commutation failure data of the converter.

[0016] The operating status of the converter is determined based on the number of converter failures.

[0017] A further technical solution is that the method for determining the harmonic detection method of the transformer in different operating current ranges is as follows:

[0018] Based on the deviation of temperature monitoring data between thyristors in the operating current range, determine the thyristors in the operating current range whose temperature monitoring data deviation from other thyristors is greater than a preset temperature deviation threshold, and identify them as temperature deviation thyristors.

[0019] The commutation bridge with temperature deviation thyristors is identified and used as a screening commutation bridge for deviation.

[0020] Based on the configuration data of the converter bridge with screening deviation in different operating current ranges, the harmonic detection method of the transformer in different operating current ranges is determined.

[0021] In a second aspect, the present invention provides a computer system comprising: a memory and a processor connected in communication, and a computer program stored in the memory and capable of running on the processor, wherein the processor executes the aforementioned harmonic detection method for a transformer when running the computer program.

[0022] Other features and advantages will be set forth in the following description, and the objects and other advantages of the invention are realized and obtained through the structures particularly pointed out in the description and the drawings.

[0023] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0024] The above and other features and advantages of the present invention will become more apparent from a detailed description of exemplary embodiments thereof with reference to the accompanying drawings;

[0025] Figure 1 This is a flowchart of a harmonic detection method for transformers;

[0026] Figure 2 This is a flowchart to determine whether the converter's operating status meets the requirements;

[0027] Figure 3 This is a flowchart illustrating the method for determining the anomaly monitoring device in a temperature monitoring system;

[0028] Figure 4 It is a framework diagram of a computer system. Detailed Implementation

[0029] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments of this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this specification.

[0030] Example 1

[0031] Specifically, such as Figure 1 As shown, a harmonic detection method for transformers includes the following:

[0032] S1 determines the converter failure data based on the converter's operating data, and when the converter's operating status meets the requirements based on the converter failure data, determines the temperature monitoring data in different converter bridges of the converter.

[0033] Furthermore, the converter failure data includes the number of times the converter failed to commutate.

[0034] Specifically, such as Figure 2 As shown, determining that the operating status of the converter meets the requirements specifically includes:

[0035] The number of commutation failures of the converter is determined based on the commutation failure data of the converter.

[0036] The operating status of the converter is determined based on the number of converter failures.

[0037] Specifically, when the number of switching failures of the converter exceeds a preset threshold, the operating status of the converter is determined to be unsatisfactory.

[0038] Furthermore, it should be noted that when the operating state of the converter does not meet the requirements, a preset strategy is used for harmonic detection processing in different operating current ranges.

[0039] In another embodiment, determining that the operating state of the converter meets the requirements specifically includes:

[0040] The number of commutation failures of the converter is determined based on the commutation failure data of the converter.

[0041] The number of commutation failures of the converter within the operating current range is determined based on the number of commutation failures.

[0042] The operating status of the converter is determined by the number of commutation failures in different operating current ranges.

[0043] Furthermore, if the number of operating current intervals with a number of commutation failures is within the preset range, then the operating state of the converter is determined to be unsatisfactory.

[0044] It is understood that the temperature monitoring data is determined based on the temperature monitoring device installed on the converter.

[0045] In another embodiment, determining that the operating state of the converter meets the requirements specifically includes:

[0046] The number of commutation failures of the converter is determined based on the commutation failure data of the converter.

[0047] The number of commutation failures of the converter within the operating current range is determined based on the number of commutation failures.

[0048] By analyzing the different numbers of converter failures, it is determined whether the operating status of the converter meets the requirements.

[0049] S2 determines the abnormal changes in the temperature monitoring data of different converter bridges based on the temperature monitoring data, and determines the abnormal monitoring devices among the temperature monitoring devices based on the abnormal changes.

[0050] Furthermore, the abnormal fluctuations in the temperature monitoring data include the number of abnormal fluctuations and the amount of temperature change between different numbers of abnormal fluctuations and adjacent time points.

[0051] Specifically, such as Figure 3 As shown, the method for determining the abnormality monitoring device in the temperature monitoring device is as follows:

[0052] Based on the abnormal changes, the deviation between the temperature monitoring data of different temperature monitoring devices and the temperature monitoring data at adjacent times is determined, and this deviation is used as the change in monitoring data.

[0053] The number of abnormal fluctuations for different temperature monitoring devices is determined based on the amount of change in the monitoring data.

[0054] The temperature monitoring device is determined as an abnormal monitoring device based on the number of abnormal changes.

[0055] Specifically, the number of abnormal changes refers to the number of times the monitored data changes are outside the preset range of changes. When the number of abnormal changes is large, i.e. greater than the threshold, the temperature monitoring device is determined to be an abnormality detection device.

[0056] S3 uses the distribution data of abnormal monitoring devices in different converter bridges, combined with the variation of operating voltage of thyristors in different converter bridges in different operating current ranges, to determine that when the monitoring reliability of the converter meets the requirements, the deviation of temperature monitoring data between thyristors in different converter bridges in different operating current ranges is used to determine the harmonic detection method of the transformer in different operating current ranges.

[0057] It should be noted that determining whether the monitoring reliability of the converter meets the requirements specifically includes:

[0058] Based on the distribution data of the abnormal monitoring devices in the converter bridge, the converter bridge with abnormal monitoring devices is identified and designated as the abnormal monitoring converter bridge;

[0059] Based on the operating data of the thyristors in different anomaly monitoring converter bridges, the deviation of the proportion of the operating voltage of different thyristors in different operating current ranges in different anomaly monitoring converter bridges is determined. The anomaly monitoring converter bridge with thyristors whose average deviation does not meet the requirements is regarded as the characteristic deviation converter bridge.

[0060] The characteristic deviation converter bridge is used to determine whether the monitoring reliability of the converter meets the requirements.

[0061] Specifically, when the average deviation is greater than a certain deviation threshold, it can be determined that the requirements are not met, indicating that there is a certain difference in the operating characteristics of the thyristor. Therefore, it can be used as a characteristic deviation converter bridge.

[0062] Furthermore, it should be noted that if the number of characteristic deviation converter bridges in the converter is too large, specifically more than two, the proportion of different thyristors may change due to variations in the operating current, as the operating characteristics of the characteristic deviation converter bridges differ during operation. Therefore, if there is an abnormality monitoring device and the operating characteristics are also abnormal, it can be determined that the monitoring reliability of the converter is difficult to meet the requirements.

[0063] In another embodiment, determining that the monitoring reliability of the converter meets the requirements specifically includes:

[0064] S21 uses the distribution data of the abnormal monitoring devices in the converter bridge to determine the converter bridge with abnormal monitoring devices and uses it as the abnormal monitoring converter bridge.

[0065] In one embodiment, the above steps include the following three cases:

[0066] Scenario 1: When the number of abnormal monitoring devices in the converter bridge is too large, specifically when it exceeds the threshold, it can be directly determined that the monitoring reliability of the converter does not meet the requirements.

[0067] Scenario 2: Even if the number of abnormal monitoring devices in the converter bridge is not large, if the number of abnormal monitoring converter bridges is too large, it can be directly determined that the monitoring reliability of the converter does not meet the requirements.

[0068] Case 3: If the number of abnormal monitoring converter bridges is not large, but if the number of abnormal monitoring devices is greater than the preset number, it can be determined that the monitoring reliability of the converter does not meet the requirements. The excessive or insufficient number in the above cases is determined by a threshold method. When all the above conditions are met, proceed to the next step.

[0069] S22 determines the deviation of the proportion of the operating voltage of different thyristors in different operating current ranges in different abnormal monitoring converter bridges based on the operating data of the thyristors in different abnormal monitoring converter bridges, and identifies the thyristors whose deviation of the proportion of the operating voltage in different operating current ranges in different abnormal monitoring converter bridges does not meet the requirements, and regards them as characteristic variation thyristors.

[0070] Understandably, before proceeding to the next step, it is necessary to determine whether the number of characteristic-variable thyristors meets the requirements and whether the number of abnormal monitoring converter bridges with characteristic-variable thyristors meets the requirements. If either the number of characteristic-variable thyristors or the number of abnormal monitoring converter bridges with characteristic-variable thyristors does not meet the requirements, i.e. the number is too large, it can be determined by using a threshold method. In this case, it can be directly determined that the monitoring reliability of the converter is difficult to meet the requirements.

[0071] Furthermore, even if the above data meet the requirements, it is still necessary to further check whether the number of abnormal monitoring devices for the converter bridge, which are used to monitor thyristors with varying characteristics, meets the requirements. Specifically, if the number of abnormal monitoring devices for the converter bridge, which are used to monitor thyristors with varying characteristics, is greater than the preset number of devices, it can also be determined that the monitoring reliability of the converter is difficult to meet the requirements.

[0072] S23 determines whether the monitoring reliability of the converter meets the requirements by using the configuration data of the characteristic variation thyristors in the different anomaly monitoring converter bridges.

[0073] In one possible embodiment, the characteristic anomaly value is determined based on the sum of the proportions of characteristic-variable thyristors in different anomaly monitoring converter bridges. When the characteristic anomaly value is above a preset anomaly value, it is determined that the monitoring reliability of the converter does not meet the requirements.

[0074] It should be noted that when the monitoring reliability of the converter does not meet the requirements, a preset strategy is used for harmonic detection processing in different operating current ranges.

[0075] Specifically, the method for determining the harmonic detection method of the transformer in different operating current ranges is as follows:

[0076] Based on the deviation of temperature monitoring data between thyristors in the operating current range, determine the thyristors in the operating current range whose temperature monitoring data deviation from other thyristors is greater than a preset temperature deviation threshold, and identify them as temperature deviation thyristors.

[0077] The commutation bridge with temperature deviation thyristors is identified and used as a screening commutation bridge for deviation.

[0078] Based on the configuration data of the converter bridge with screening deviation in different operating current ranges, the harmonic detection method of the transformer in different operating current ranges is determined.

[0079] Specifically, based on the configuration data of the converter bridge with screening deviations in different operating current ranges, the harmonic detection method for the transformer in different operating current ranges is determined, including:

[0080] When the number of filter deviation converter bridges is too large in different operating current ranges, a preset strategy is used to perform harmonic detection processing in different operating current ranges.

[0081] When there is an operating current range in which the number of converter bridges with screening deviation is not excessive, the number of different converter bridges belonging to screening deviation overcurrent bridges in different operating current ranges is obtained. When the number of converters belonging to screening deviation overcurrent bridges is excessive, a preset strategy is used to perform harmonic detection processing in different operating current ranges. Whether it is excessive is determined by a threshold method. Specifically, if it is greater than the threshold, it is set as excessive.

[0082] It should also be noted that when the number of converters with excessive screening deviation overcurrent bridges is not excessive, if there are no screening deviation overcurrent bridges in the operating current range, there is no need to perform harmonic current detection processing. If the number of screening deviation overcurrent bridges in the operating current range is large, i.e., greater than the threshold, then a preset strategy is used to perform harmonic detection processing in the operating current range. If the number of screening deviation overcurrent bridges in the operating current range is not large, then a second preset strategy is used to perform harmonic detection processing in the operating current range.

[0083] Specifically, the first preset strategy is to perform harmonic detection on all harmonics from the 2nd to the 100th order, and determine that there is an anomaly when the amplitude of the harmonic current or the harmonic distortion rate of any harmonic order does not meet the requirements, i.e., it is too large. The second preset strategy is to perform harmonic detection only on harmonics from the 2nd to the 40th order, and determine that there is an anomaly when the total harmonic distortion rate of the harmonic does not meet the requirements, i.e., it is too large.

[0084] In another embodiment, the method for determining the harmonic detection method of the transformer in different operating current ranges is as follows:

[0085] S41 uses the deviation of temperature monitoring data between thyristors in the operating current range to determine the thyristors in the operating current range whose temperature monitoring data deviation from other thyristors is greater than a preset temperature deviation threshold, and uses them as temperature deviation thyristors. The commutator bridge with temperature deviation thyristors is obtained and used as a filter deviation commutator bridge.

[0086] It should be noted that in the above steps, if there is no filter deviation converter bridge, the second preset strategy is used to perform harmonic detection processing for different operating current ranges.

[0087] In addition, it should be noted that if there are filter deviation converter bridges and the number of filter deviation converter bridges is large, specifically when it exceeds a certain number threshold, a preset strategy will be used for harmonic detection processing in different operating current ranges.

[0088] S42 determines the number of converter bridges that belong to the screening deviation converter bridges in different operating current ranges based on the composition data of the screening deviation converter bridges in different operating current ranges, and uses them as the matching quantity.

[0089] It is understandable that in the above steps, if there is no converter bridge with a matching number greater than the preset matching number threshold, it is determined that there is no converter bridge with deviation in operating uniformity in different operating current ranges. Therefore, if there is no filter deviation overcurrent bridge in the operating current range, there is no need to perform harmonic current detection processing. If the number of filter deviation overcurrent bridges in the operating current range is large, i.e., greater than the threshold, then a preset strategy is used to perform harmonic detection processing in the operating current range. If the number of filter deviation overcurrent bridges in the operating current range is not large, then a second preset strategy is used to perform harmonic detection processing in the operating current range.

[0090] In addition, if there are converter bridges with a matching number greater than the preset matching number threshold, and if the number of converter bridges with a matching number greater than the preset matching number threshold is large, that is, greater than a certain threshold, then a preset strategy will be used to detect and process harmonic currents in different operating current ranges.

[0091] S43 determines the harmonic detection method for the transformer in different operating current ranges based on the number of matches and whether different converter bridges belong to the screening deviation converter bridges in different operating current ranges.

[0092] In one embodiment, a converter bridge with three or more matching bridges is designated as a matching deviation converter bridge. If the number of matching deviation converter bridges is four or more, a preset strategy is used to detect harmonic currents in different operating current ranges. If a matching deviation converter bridge exists in the operating current range, a preset strategy is used to detect harmonics in that operating current range. If no matching deviation converter bridge exists in the operating current range, a second preset strategy is used to detect harmonics in that operating current range.

[0093] Example 2

[0094] Secondly, such asFigure 4 As shown, the present invention provides a computer system comprising: a memory and a processor connected in communication, and a computer program stored in the memory and capable of running on the processor, wherein the processor executes the above-described harmonic detection method for a transformer when running the computer program.

[0095] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the embodiments of apparatus, devices, and non-volatile computer storage media are basically similar to the method embodiments, so the descriptions are relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0096] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0097] The above description is merely one or more embodiments of this specification and is not intended to limit this specification. Various modifications and variations can be made to the one or more embodiments of this specification by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of one or more embodiments of this specification should be included within the scope of the claims of this specification.

Claims

1. A method for harmonic detection in transformers, characterized in that, Specifically, it includes: Based on the converter's operating data, the converter's commutation failure data is determined. Based on the commutation failure data, when the converter's operating status meets the requirements, the temperature monitoring data in different converter bridges of the converter is determined. Based on the temperature monitoring data, determine the abnormal changes in the temperature monitoring data of the temperature monitoring devices in different converter bridges, and determine the abnormal monitoring devices among the temperature monitoring devices based on the abnormal changes. Based on the distribution data of abnormal monitoring devices in different converter bridges, and combined with the variation of operating voltage of thyristors in different converter bridges in different operating current ranges, it is determined that when the monitoring reliability of the converter meets the requirements, the deviation of temperature monitoring data between thyristors in different converter bridges in different operating current ranges is used to determine the harmonic detection method of the transformer in different operating current ranges.

2. The harmonic detection method for transformers as described in claim 1, characterized in that, The converter failure data includes the number of times the converter failed to commutate.

3. The harmonic detection method for transformers as described in claim 1, characterized in that, Determining that the operating status of the converter meets the requirements specifically includes: The number of commutation failures of the converter is determined based on the commutation failure data of the converter. The operating status of the converter is determined based on the number of converter failures.

4. The harmonic detection method for transformers as described in claim 1, characterized in that, The temperature monitoring data is determined based on the temperature monitoring device installed on the converter.

5. The harmonic detection method for transformers as described in claim 1, characterized in that, The abnormal fluctuations in the temperature monitoring data include the number of abnormal fluctuations and the amount of temperature change between different abnormal fluctuations and adjacent time points.

6. The harmonic detection method for transformers as described in claim 1, characterized in that, The method for determining the abnormal monitoring device in the temperature monitoring device is as follows: Based on the abnormal changes, the deviation between the temperature monitoring data of different temperature monitoring devices and the temperature monitoring data at adjacent times is determined, and this deviation is used as the change in monitoring data. The number of abnormal fluctuations for different temperature monitoring devices is determined based on the amount of change in the monitoring data. The temperature monitoring device is determined as an abnormal monitoring device based on the number of abnormal changes.

7. The harmonic detection method for transformers as described in claim 6, characterized in that, The number of abnormal changes refers to the number of times the monitored data changes outside the preset range.

8. The harmonic detection method for transformers as described in claim 1, characterized in that, When the monitoring reliability of the converter does not meet the requirements, a preset strategy is used for harmonic detection processing in different operating current ranges.

9. The harmonic detection method for transformers as described in claim 1, characterized in that, The method for determining the harmonic detection method of the transformer in different operating current ranges is as follows: Based on the deviation of temperature monitoring data between thyristors in the operating current range, determine the thyristors in the operating current range whose temperature monitoring data deviation from other thyristors is greater than a preset temperature deviation threshold, and identify them as temperature deviation thyristors. The commutation bridge with temperature deviation thyristors is identified and used as a screening commutation bridge for deviation. Based on the configuration data of the converter bridge with screening deviation in different operating current ranges, the harmonic detection method of the transformer in different operating current ranges is determined.

10. A computer system, comprising: A memory and processor connected in communication, and a computer program stored in the memory and capable of running on the processor, characterized in that, when the processor runs the computer program, it executes a harmonic detection method for a transformer as described in any one of claims 1-9.

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