An abnormal monitoring and evaluation method and system for optical CT analog quantities in a converter station

Abstract

The present invention discloses a method and system for abnormal monitoring and evaluation of optical CT analog quantities in a converter station. The method includes: reading the fault recording files built in each DC control and protection host in the converter station to obtain the optical CT analog quantity data collected by each DC control and protection host; calculating the effective value, maximum value, and minimum value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data, wherein the effective value of the optical CT analog quantity is obtained through arithmetic processing of a plurality of optical CT analog quantities collected by the corresponding optical CT within a preset time range; and identifying abnormal data in the optical CT analog quantity data collected by each DC control and protection host based on a preset abnormal data detection rule. The present invention realizes automatic collection of optical CT analog quantity data of each DC control and protection host; can automatically identify abnormal data, and effectively evaluate the accuracy of the optical CT analog quantity.

Description

Technical Field

[0001] The present invention relates to the technical field of smart power grids, and particularly to an abnormal monitoring and evaluation method and system for optical CT analog quantities in a converter station. Background Art

[0002] As a key facility in the power system for converting AC and DC electrical energy, the DC field and AC filter areas configured inside a converter station play a crucial role in ensuring the efficient and stable transmission of electrical energy. In these key areas, the application of optical current transformers (abbreviated as optical CTs) is becoming increasingly widespread. With advantages such as high precision, high stability, and strong anti-electromagnetic interference ability, they have become important measurement components in modern power systems.

[0003] The optical CT analog quantity needs to go through a series of transmission links to reach the control and protection host, including the optical CT itself, the electronic unit, the merging unit, and finally the control and protection host. The entire transmission process uses optical signals exclusively, effectively avoiding the influence of electromagnetic interference on the measurement accuracy. However, this also poses extremely high requirements for the measurement accuracy of the optical CT analog quantity, because any tiny measurement deviation may directly affect the normal operation of the DC control and protection function, and may further lead to power transmission deviation and misoperation of the protection system, posing a threat to the safe and stable operation of the power system.

[0004] Currently, for the accuracy evaluation of optical CT analog quantities, it mainly relies on manual transcription and manual comparison. This method not only has a large workload and low efficiency, but is also easily affected by human factors, making it difficult to guarantee the accuracy of the analysis results. Especially in large-scale and complex power systems, the method of manually monitoring and evaluating optical CT analog quantities has been difficult to meet the actual needs.

[0005] Therefore, it is necessary to propose a more effective method for monitoring and evaluating the accuracy of optical CT analog quantities. Summary of the Invention

[0006] To solve the technical problem that it is difficult to effectively evaluate the accuracy of optical CT analog quantities in the prior art, the present invention provides an abnormal monitoring and evaluation method and system for optical CT analog quantities in a converter station.

[0007] In a first aspect, an embodiment of the present invention provides an abnormal monitoring and evaluation method for optical CT analog quantities in a converter station, including:

[0008] Reading the fault recording files built in each DC control and protection host in the converter station to obtain the optical CT analog quantity data collected by each of the DC control and protection hosts, where the optical CT analog quantity data includes the optical CT analog quantities collected by each optical CT in the DC field area of the converter station at different sampling times;

[0009] Calculate the effective value, maximum value, and minimum value of the optical CT analog quantity corresponding to each optical CT in each of the optical CT analog quantity data, where the effective value of the optical CT analog quantity is obtained based on the arithmetic processing of a plurality of optical CT analog quantities collected by the corresponding optical CT within a preset time range;

[0010] Identify abnormal data in the optical CT analog quantity data collected by each DC control and protection host based on a preset abnormal data detection rule;

[0011] Among them, the preset abnormal data detection rule includes identifying abnormal effective values of optical CT analog quantities based on the comparison of the effective values of the optical CT analog quantities corresponding to the same optical CT in each of the optical CT analog quantity data, identifying abnormal maximum values of optical CT analog quantities based on the comparison of the effective values of the optical CT analog quantities corresponding to each optical CT in each of the optical CT analog quantity data with the maximum value of the optical CT analog quantity, identifying abnormal minimum values of optical CT analog quantities based on the comparison of the effective values of the optical CT analog quantities corresponding to each optical CT in each of the optical CT analog quantity data with the minimum value of the optical CT analog quantity, and identifying abnormal optical CT analog quantities based on the comparison of the optical CT analog quantities collected by each optical CT at different sampling times in each of the optical CT analog quantity data with a first preset threshold.

[0012] Preferably, the preset abnormal data detection rule further includes identifying abnormal differential currents based on the comparison of each differential current in the DC field area of the converter station with a second preset threshold.

[0013] Preferably, the preset abnormal data detection rule further includes identifying abnormal zero drift values based on the comparison of the zero drift values of each optical CT analog quantity in each of the optical CT analog quantity data with a third preset threshold.

[0014] Preferably, after identifying the abnormal data in the optical CT analog quantity data collected by each DC control and protection host based on the preset abnormal data detection rule, it further includes:

[0015] Visualize the optical CT analog quantity data collected by each DC control and protection host, and highlight the identified abnormal data.

[0016] Preferably, the effective value of the optical CT analog quantity is obtained based on the arithmetic processing of a plurality of optical CT analog quantities collected by the corresponding optical CT within a preset time range, including:

[0017] Calculate the root mean square value of a number of optical CT analog quantities collected by the optical CT within a preset time range, and characterize the root mean square value as the effective value of the optical CT analog quantity corresponding to the optical CT, where the preset time range starts from the second power frequency cycle and ends at the Nth power frequency cycle, and N is an integer greater than 2.

[0018] Preferably, the identifying of the abnormal optical CT analog quantity effective value based on the comparison of the effective values of the optical CT analog quantities corresponding to the same optical CT in each optical CT analog quantity data includes:

[0019] Arrange the effective values of the optical CT analog quantities corresponding to the same optical CT in each optical CT analog quantity data in the arrangement order of the DC control and protection main machines in the converter station, and characterize the effective value of the optical CT analog quantity in the middle position as the reference value;

[0020] Based on the comparison between the effective value of the optical CT analog quantity corresponding to the same optical CT in each optical CT analog quantity data and the reference value, when the comparison result shows that the difference between the effective value of the optical CT analog quantity and the reference value is not within the first preset range, the effective value of the optical CT analog quantity is an abnormal optical CT analog quantity effective value.

[0021] Preferably, the identifying of the abnormal maximum value of the optical CT analog quantity based on the comparison between the effective value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data and the maximum value of the optical CT analog quantity includes:

[0022] When the comparison result shows that the difference between the maximum value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data and the effective value of the optical CT analog quantity is not within the second preset range, the maximum value of the optical CT analog quantity is an abnormal maximum value of the optical CT analog quantity.

[0023] Preferably, the identifying of the abnormal minimum value of the optical CT analog quantity based on the comparison between the effective value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data and the minimum value of the optical CT analog quantity includes:

[0024] When the comparison result shows that the difference between the effective value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data and the minimum value of the optical CT analog quantity is not within the third preset range, the minimum value of the optical CT analog quantity is an abnormal minimum value of the optical CT analog quantity.

[0025] In a second aspect, an embodiment of the present invention provides an abnormal monitoring and evaluation system for optical CT analog quantities in a converter station, including:

[0026] A data acquisition module, which is used to read the fault recording files of each DC control and protection host built in the converter station, and obtain the optical CT analog quantity data collected by each of the DC control and protection hosts. Among them, the optical CT analog quantity data includes the optical CT analog quantities collected by each optical CT in the DC field area of the converter station at different sampling times;

[0027] A data calculation module, which is used to calculate the effective value, maximum value and minimum value of the optical CT analog quantity corresponding to each optical CT in each of the optical CT analog quantity data. Among them, the effective value of the optical CT analog quantity is obtained based on the arithmetic processing of a number of optical CT analog quantities collected by the corresponding optical CT within a preset time range;

[0028] An anomaly detection module, which is used to identify the abnormal data in the optical CT analog quantity data collected by each of the DC control and protection hosts based on a preset abnormal data detection rule;

[0029] Among them, the preset abnormal data detection rule includes identifying abnormal optical CT analog quantity effective values based on the comparison of the optical CT analog quantity effective values corresponding to the same optical CT in each of the optical CT analog quantity data, identifying abnormal optical CT analog quantity maximum values based on the comparison of the optical CT analog quantity effective values corresponding to each optical CT in each of the optical CT analog quantity data with the optical CT analog quantity maximum value, identifying abnormal optical CT analog quantity minimum values based on the comparison of the optical CT analog quantity effective values corresponding to each optical CT in each of the optical CT analog quantity data with the optical CT analog quantity minimum value, and identifying abnormal optical CT analog quantities based on the comparison of the optical CT analog quantities collected by each optical CT at different sampling times in each of the optical CT analog quantity data with a first preset threshold.

[0030] Preferably, it further includes:

[0031] A data display module, which is used to visualize the optical CT analog quantity data collected by each of the DC control and protection hosts and highlight the identified abnormal data.

[0032] Compared with the prior art, the anomaly monitoring and evaluation method and system for the optical CT analog quantity of a converter station in an embodiment of the present invention has the beneficial effects that: based on the fault recording files built in the DC control and protection host, it realizes the automatic acquisition of the optical CT analog quantity data of each DC control and protection host; based on the preset abnormal data detection rule, it realizes automatic analysis such as horizontal comparison of the optical CT analog quantity effective values corresponding to the same optical CT among the DC control and protection hosts and vertical comparison of the optical CT analog quantities collected by the same optical CT at different times, can automatically identify abnormal data, and effectively evaluate the accuracy of the optical CT analog quantity. Description of the Drawings

[0033] Figure 1It is a schematic flowchart of a method for abnormal monitoring and evaluation of optical CT analog quantities in a converter station according to an embodiment of the present invention;

[0034] Figure 2 It is a schematic diagram of the data format of each sampling point in the waveform recording data file according to an embodiment of the present invention;

[0035] Figure 3 It is a schematic flowchart of a method for identifying the effective value of abnormal optical CT analog quantities according to an embodiment of the present invention;

[0036] Figure 4 It is another schematic flowchart of a method for abnormal monitoring and evaluation of optical CT analog quantities in a converter station according to an embodiment of the present invention;

[0037] Figure 5 It is a schematic structural diagram of a system for abnormal monitoring and evaluation of optical CT analog quantities in a converter station according to an embodiment of the present invention;

[0038] Figure 6 It is another schematic structural diagram of a system for abnormal monitoring and evaluation of optical CT analog quantities in a converter station according to an embodiment of the present invention. Detailed implementation manners

[0039] The following combines the accompanying drawings and embodiments to further describe in detail the specific implementation manners of the present invention. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0040] In the description of the present invention, it should be understood that the terms "first" and "second" etc. adopted in the present invention are used to distinguish different objects, rather than to describe a specific order.

[0041] In the description of the present invention, it should be noted that unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the art. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0042] As Figure 1 shown, the embodiment of the present invention provides a method for abnormal monitoring and evaluation of optical CT analog quantities in a converter station, including the steps of:

[0043] S1. Read the fault waveform recording files built in each DC control and protection host in the converter station to obtain the optical CT analog quantity data collected by each DC control and protection host;

[0044] In a converter station, the optical CT data in the DC field area is stored in the DC control and protection host, while the optical CT data in the AC filter area is stored in the filter control and protection host. There are mainly two ways to view the optical CT analog quantity: one is the online method, that is, the program monitors the data points online; the other is the offline method, that is, by viewing the built-in fault recording file to obtain the data content. This step reads the fault recording files built in each DC control and protection host in the converter station based on the keyword retrieval method to obtain the optical CT analog quantity data collected by each DC control and protection host. The optical CT analog quantity data includes the optical CT analog quantities collected by each optical CT in the DC field area of the converter station at different sampling times.

[0045] It should be noted that the built-in fault recording file of the DC control and protection host in the converter station is in the standard COMTRADE format (a kind of recording data format) and consists of three format files. Among them, the file with the suffix CFG is the channel configuration file, which configures the name of the optical CT; the file with the suffix DAT is the recording data file. A recording data file includes multiple data channels, and each data channel represents an optical CT. A recording data file includes multiple sampling points, and each sampling point includes a sampling point serial number, a sampling time, and sampling data. The sampling data includes the optical CT analog quantities collected by multiple optical CTs, which can be seen Figure 2 .. In this embodiment, the size of an optical CT analog quantity is two bytes. It can be understood that the sampling point is the basic unit in the recording data file, which represents the sampling data at a specific moment.

[0046] S2. Calculate the effective value, maximum value, and minimum value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data;

[0047] The effective value of the optical CT analog quantity is obtained based on the arithmetic processing of several optical CT analog quantities collected by the corresponding optical CT within a preset time range. Specifically, calculate the root mean square value of several optical CT analog quantities collected by the optical CT within the preset time range, and represent the root mean square value as the effective value of the optical CT analog quantity corresponding to the optical CT.

[0048] The preset time range starts from the second power frequency cycle and ends at the Nth power frequency cycle, where N is an integer greater than 2. In this embodiment, the preset time range starts from the second power frequency cycle and ends at the sixth power frequency cycle, that is, the preset time range is 5 power frequency cycles, and the sampling frequency is 50 Hz. Each power frequency cycle is 20 ms, so one optical CT analog quantity is collected in each power frequency cycle. Then, 5 optical CT analog quantities are collected within the preset time range, and the root mean square value of these 5 optical CT analog quantities is calculated to obtain the corresponding effective value of the optical CT analog quantity.

[0049] It can be understood that the maximum value of the optical CT analog quantity is the maximum value among the optical CT analog quantities collected by the same optical CT at different sampling moments, and the minimum value of the optical CT analog quantity is the minimum value among the optical CT analog quantities collected by the same optical CT at different sampling moments.

[0050] S3. Identify the abnormal data in the optical CT analog quantity data collected by each DC control and protection host based on a preset abnormal data detection rule;

[0051] The preset abnormal data detection rule includes identifying the abnormal effective value of the optical CT analog quantity based on the comparison of the effective values of the optical CT analog quantities corresponding to the same optical CT in each optical CT analog quantity data, identifying the abnormal maximum value of the optical CT analog quantity based on the comparison of the effective value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data with the maximum value of the optical CT analog quantity, identifying the abnormal minimum value of the optical CT analog quantity based on the comparison of the effective value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data with the minimum value of the optical CT analog quantity, and identifying the abnormal optical CT analog quantity based on the comparison of the optical CT analog quantities collected by each optical CT at different sampling moments in each optical CT analog quantity data with a first preset threshold.

[0052] As Figure 3 shown, identifying the abnormal effective value of the optical CT analog quantity based on the comparison of the effective values of the optical CT analog quantities corresponding to the same optical CT in each optical CT analog quantity data includes the steps of:

[0053] S301. Arrange the effective values of the optical CT analog quantities corresponding to the same optical CT in each optical CT analog quantity data in the arrangement order of the DC control and protection hosts in the converter station, and characterize the effective value of the optical CT analog quantity in the middle position as the reference value;

[0054] S302. Based on the comparison of the effective value of the optical CT analog quantity corresponding to the same optical CT in each optical CT analog quantity data with the reference value, when the comparison result shows that the difference between the effective value of the optical CT analog quantity and the reference value is not within the first preset range, the effective value of the optical CT analog quantity is the abnormal effective value of the optical CT analog quantity.

[0055] In the first preset range of this embodiment is 0 to five-thousandths of the reference value. That is to say, when the difference between the effective value of the optical CT analog quantity and the reference value exceeds five-thousandths of the reference value, the effective value of the optical CT analog quantity is identified as the abnormal effective value of the optical CT analog quantity.

[0056] Identify the abnormal maximum value of the optical CT analog quantity based on the comparison between the effective value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data and the maximum value of the optical CT analog quantity. Specifically, when the comparison result shows that the difference between the maximum value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data and the effective value of the optical CT analog quantity is not within the second preset range, the maximum value of the optical CT analog quantity is the abnormal maximum value of the optical CT analog quantity.

[0057] In this embodiment, the second preset range is 0 to 5% of the effective value of the optical CT analog quantity. That is to say, when the maximum value of the optical CT analog quantity exceeds 105% of the effective value of the optical CT analog quantity, identify the maximum value of the optical CT analog quantity as the abnormal maximum value of the optical CT analog quantity.

[0058] Identify the abnormal minimum value of the optical CT analog quantity based on the comparison between the effective value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data and the minimum value of the optical CT analog quantity. Specifically, when the comparison result shows that the difference between the effective value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data and the minimum value of the optical CT analog quantity is not within the third preset range, the minimum value of the optical CT analog quantity is the abnormal minimum value of the optical CT analog quantity.

[0059] In this embodiment, the third preset range is 0 to 5% of the effective value of the optical CT analog quantity. That is to say, when the minimum value of the optical CT analog quantity is less than 95% of the effective value of the optical CT analog quantity, identify the minimum value of the optical CT analog quantity as the abnormal minimum value of the optical CT analog quantity.

[0060] Identify the abnormal optical CT analog quantity based on the comparison between the optical CT analog quantity collected by each optical CT at different sampling times in each optical CT analog quantity data and the first preset threshold. Specifically, when the comparison result shows that the deviation between the optical CT analog quantity collected by each optical CT at different sampling times in each optical CT analog quantity data and the first preset threshold exceeds 5%, the optical CT analog quantity is the abnormal optical CT analog quantity.

[0061] In this embodiment, the first preset threshold is the rated value of the optical CT. That is to say, when the deviation between the optical CT analog quantity and the corresponding rated value of the optical CT exceeds 5%, identify the optical CT analog quantity as the abnormal optical CT analog quantity.

[0062] The preset abnormal data detection rule also includes identifying the abnormal differential current based on the comparison between each differential current in the DC field area of the converter station and the second preset threshold. Specifically, when the comparison result shows that each differential current in the DC field area of the converter station exceeds the second preset threshold, the differential current is the abnormal differential current.

[0063] In this embodiment, the second preset threshold is 50A. That is to say, when the differential current in the DC field area of the converter station exceeds 50A, identify the differential current as the abnormal differential current.

[0064] The preset abnormal data detection rule also includes identifying abnormal zero drift values based on the comparison between the zero drift value of each optical CT analog quantity in each optical CT analog quantity data and a third preset threshold. Specifically, when the comparison result shows that the zero drift value of each optical CT analog quantity in each optical CT analog quantity data exceeds the third preset threshold, the zero drift value is an abnormal zero drift value.

[0065] In this embodiment, the third preset threshold is one percent of the rated value of the optical CT analog quantity. That is to say, when the zero drift value of the optical CT analog quantity exceeds one percent of the rated value of the optical CT analog quantity, the zero drift value is identified as an abnormal zero drift value. It should be noted that the rated values of the optical CT analog quantities in different areas of the converter station are different. The rated value of the optical CT analog quantity in the DC field area is 5000A. Therefore, the third preset threshold is actually 50A.

[0066] As Figure 4 shown, after step S3, an abnormal monitoring and evaluation method for the optical CT analog quantity of a converter station according to an embodiment of the present invention further includes the steps:

[0067] S4. Visualize the optical CT analog quantity data collected by each DC control and protection host, and highlight the identified abnormal data.

[0068] Specifically, based on the Excel tool, visualize the optical CT analog quantity data collected by each DC control and protection host, and display the identified abnormal data in bold. See Table 1 for details.

[0069] Table 1 Analysis Table of the Effective Values of the Optical CT Analog Quantities of a Certain Converter Station

[0070]

[0071] Among them, PPR1A, PPR1B, PPR1C, PCP1A, and PCP1B are the names of the DC control and protection hosts respectively, IDCIP, IDC2P, IDC1N, IDC2N, IDL, INBS, IDNC, and IDNE are the names of the optical CTs respectively, and each data is the effective value of the optical CT analog quantity of different DC control and protection hosts under different optical CTs, with the unit of ampere (A). When the difference between the effective value of the optical CT analog quantity and the reference value exceeds five-thousandths of the reference value, the effective value of the optical CT analog quantity is identified as an abnormal effective value of the optical CT analog quantity, and the identified abnormal effective value of the optical CT analog quantity is displayed in bold.

[0072] In an embodiment of the present invention, a method for abnormal monitoring and evaluation of optical CT analog quantities in a converter station is based on a fault recording file built in a DC control and protection host, and realizes automatic acquisition of optical CT analog quantity data of each DC control and protection host; based on a preset abnormal data detection rule, automatic analysis such as horizontal comparison of the effective values of optical CT analog quantities corresponding to the same optical CT between DC control and protection hosts and vertical comparison of the optical CT analog quantities collected by the same optical CT at different times is realized, which can automatically identify abnormal data and effectively evaluate the accuracy of optical CT analog quantities.

[0073] Based on the above abnormal monitoring and evaluation method, as Figure 5 shown, an embodiment of the present invention provides an abnormal monitoring and evaluation system for optical CT analog quantities in a converter station, including:

[0074] A data acquisition module 1, configured to read the fault recording file built in each DC control and protection host in the converter station to obtain the optical CT analog quantity data collected by each DC control and protection host, where the optical CT analog quantity data includes the optical CT analog quantities collected by each optical CT in the DC field area of the converter station at different sampling times;

[0075] A data calculation module 2, configured to calculate the effective value, maximum value, and minimum value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data, where the effective value of the optical CT analog quantity is obtained through arithmetic processing of a plurality of optical CT analog quantities collected by the corresponding optical CT within a preset time range;

[0076] An abnormal detection module 3, configured to identify abnormal data in the optical CT analog quantity data collected by each DC control and protection host based on a preset abnormal data detection rule;

[0077] Among them, the preset abnormal data detection rule includes identifying abnormal optical CT analog quantity effective values based on the comparison of the effective values of the optical CT analog quantities corresponding to the same optical CT in each optical CT analog quantity data, identifying abnormal optical CT analog quantity maximum values based on the comparison of the effective value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data with the maximum value of the optical CT analog quantity, identifying abnormal optical CT analog quantity minimum values based on the comparison of the effective value of the optical CT analog quantity corresponding to each optical CT in each optical CT analog quantity data with the minimum value of the optical CT analog quantity, and identifying abnormal optical CT analog quantities based on the comparison of the optical CT analog quantities collected by each optical CT at different sampling times in each optical CT analog quantity data with a first preset threshold.

[0078] Further, as Figure 6 shown, an embodiment of the present invention provides an abnormal monitoring and evaluation system for optical CT analog quantities in a converter station, further including:

[0079] The data display module 4 is used to visualize the optical CT analog quantity data collected by each DC control and protection host, and highlight the identified abnormal data.

[0080] It should be noted that each module in the above abnormal monitoring and evaluation system for optical CT analog quantity of a converter station can be implemented in whole or in part by software, hardware, and their combination. The above-mentioned modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each of the above modules. For the specific limitations of an abnormal monitoring and evaluation system for optical CT analog quantity of a converter station, refer to the limitations of the abnormal monitoring and evaluation method for optical CT analog quantity of a converter station in the above text. The two have the same functions and effects and will not be elaborated here.

[0081] In summary, for the abnormal monitoring and evaluation method and system for optical CT analog quantity of a converter station in an embodiment of the present invention, based on the fault recording file built in the DC control and protection host, it realizes the automatic collection of the optical CT analog quantity data of each DC control and protection host; based on the preset abnormal data detection rules, it realizes automatic analysis such as the horizontal comparison of the effective values of the optical CT analog quantities corresponding to the same optical CT between DC control and protection hosts and the vertical comparison of the optical CT analog quantities collected by the same optical CT at different times, can automatically identify abnormal data, and effectively evaluate the accuracy of the optical CT analog quantity.

[0082] Each embodiment in this specification is described in a progressive manner. For the parts that are the same or similar in each embodiment, they can be referred to each other. Each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. It should be noted that the technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0083] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and replacements can still be made, and these improvements and replacements should also be regarded as the protection scope of the present invention.

Claims

1. A method for monitoring and evaluating abnormality of optical CT analog quantity in a converter station, characterized in that: include: Read the fault recording file of each DC control and protection host built in the converter station to obtain the optical CT analog data collected by each DC control and protection host, wherein the optical CT analog data includes the optical CT analog data collected by each optical CT in the DC field area of ​​the converter station at different sampling times; Calculating an effective value of an optical CT analog quantity, a maximum value of an optical CT analog quantity, and a minimum value of an optical CT analog quantity corresponding to each optical CT in each of the optical CT analog quantity data, wherein the effective value of the optical CT analog quantity is obtained based on the calculation and processing of a plurality of optical CT analog quantities collected by the corresponding optical CT within a preset time range; Identify abnormal data in the optical CT analog data collected by each of the DC control protection hosts based on a preset abnormal data detection rule; Wherein, the preset abnormal data detection rule includes identifying abnormal light CT analog quantity effective value based on comparison of light CT analog quantity effective value corresponding to the same light CT in each light CT analog quantity data, identifying abnormal light CT analog quantity maximum value based on comparison of light CT analog quantity effective value corresponding to each light CT in each light CT analog quantity data with light CT analog quantity maximum value, identifying abnormal light CT analog quantity minimum value based on comparison of light CT analog quantity effective value corresponding to each light CT in each light CT analog quantity data with light CT analog quantity minimum value, and identifying abnormal light CT analog quantity based on comparison of light CT analog quantity collected by each light CT at different sampling times in each light CT analog quantity data with a first preset threshold value; The comparing and identifying the abnormal light CT analog quantity effective value based on the light CT analog quantity effective value corresponding to the same light CT in each light CT analog quantity data includes: Arrange the effective value of the optical CT analog quantity corresponding to the same optical CT in each of the optical CT analog quantity data according to the arrangement order of the DC control and protection host in the converter station, and characterize the effective value of the optical CT analog quantity in the middle position as a reference value; Based on the comparison between the effective value of the light CT analog quantity corresponding to the same light CT in each of the light CT analog quantity data and the reference value, when the comparison result is that the difference between the effective value of the light CT analog quantity and the reference value is not within a first preset range, the effective value of the light CT analog quantity is an abnormal light CT analog quantity effective value.

2. The abnormal monitoring and evaluation method according to claim 1, characterized in that: The preset abnormal data detection rule also includes identifying abnormal differential currents based on a comparison between each differential current in the DC field area within the converter station and a second preset threshold.

3. The abnormal monitoring and evaluation method according to claim 1, characterized in that: The preset abnormal data detection rule also includes identifying an abnormal zero drift value based on a comparison between the zero drift value of each of the optical CT analog quantity in each of the optical CT analog quantity data and a third preset threshold.

4. The abnormality monitoring and evaluation method according to any one of claims 1 to 3, characterized in that: After identifying abnormal data in the optical CT analog data collected by each DC control protection host based on the preset abnormal data detection rule, the method further includes: The optical CT analog data collected by each DC control protection host is visualized, and the identified abnormal data is highlighted.

5. The abnormal monitoring and evaluation method according to claim 1, characterized in that: The effective value of the optical CT analog quantity is obtained based on the calculation and processing of a plurality of optical CT analog quantities collected by the optical CT within a preset time range, including: Calculate the root mean square value of a plurality of optical CT analog quantities collected by the optical CT within a preset time range, and characterize the root mean square value as the effective value of the optical CT analog quantity corresponding to the optical CT, wherein the preset time range starts from the second power frequency cycle and ends at the Nth power frequency cycle, and N is an integer greater than 2.

6. The abnormal monitoring and evaluation method according to claim 1, characterized in that: The method of identifying the abnormal maximum value of the optical CT simulation value based on the comparison between the effective value of the optical CT simulation value corresponding to each optical CT in each optical CT simulation value data and the maximum value of the optical CT simulation value includes: When the comparison result is that the difference between the maximum light CT simulation value corresponding to each light CT in each light CT simulation value data and the effective value of the light CT simulation value is not within the second preset range, the maximum light CT simulation value is the abnormal maximum light CT simulation value.

7. The abnormal monitoring and evaluation method according to claim 1, characterized in that: The step of identifying the abnormal light CT analog quantity minimum value based on the comparison between the light CT analog quantity effective value corresponding to each light CT in each light CT analog quantity data and the light CT analog quantity minimum value comprises: When the comparison result is that the difference between the effective value of the light CT simulation quantity corresponding to each light CT in each of the light CT simulation quantity data and the minimum value of the light CT simulation quantity is not within the third preset range, the minimum value of the light CT simulation quantity is an abnormal minimum value of the light CT simulation quantity.

8. A converter station optical CT analog quantity abnormal monitoring and evaluation system, characterized in that: include: A data acquisition module is used to read the fault recording file of each DC control and protection host built in the converter station, and obtain the optical CT analog data collected by each DC control and protection host, wherein the optical CT analog data includes the optical CT analog data collected by each optical CT in the DC field area of ​​the converter station at different sampling times; a data calculation module, used to calculate an effective value of an optical CT analog quantity, a maximum value of an optical CT analog quantity, and a minimum value of an optical CT analog quantity corresponding to each optical CT in each of the optical CT analog quantity data, wherein the effective value of the optical CT analog quantity is obtained based on the calculation and processing of a plurality of optical CT analog quantities collected by the corresponding optical CT within a preset time range; An abnormality detection module, used for identifying abnormal data in the optical CT analog data collected by each of the DC control protection hosts based on preset abnormal data detection rules; Wherein, the preset abnormal data detection rule includes identifying abnormal light CT analog quantity effective value based on comparison of light CT analog quantity effective value corresponding to the same light CT in each light CT analog quantity data, identifying abnormal light CT analog quantity maximum value based on comparison of light CT analog quantity effective value corresponding to each light CT in each light CT analog quantity data with light CT analog quantity maximum value, identifying abnormal light CT analog quantity minimum value based on comparison of light CT analog quantity effective value corresponding to each light CT in each light CT analog quantity data with light CT analog quantity minimum value, and identifying abnormal light CT analog quantity based on comparison of light CT analog quantity collected by each light CT at different sampling times in each light CT analog quantity data with a first preset threshold value; The comparing and identifying the abnormal light CT analog quantity effective value based on the light CT analog quantity effective value corresponding to the same light CT in each light CT analog quantity data includes: Arrange the effective value of the optical CT analog quantity corresponding to the same optical CT in each of the optical CT analog quantity data according to the arrangement order of the DC control and protection host in the converter station, and characterize the effective value of the optical CT analog quantity in the middle position as a reference value; Based on the comparison between the effective value of the light CT analog quantity corresponding to the same light CT in each of the light CT analog quantity data and the reference value, when the comparison result is that the difference between the effective value of the light CT analog quantity and the reference value is not within a first preset range, the effective value of the light CT analog quantity is an abnormal light CT analog quantity effective value.

9. The abnormal monitoring and evaluation system according to claim 8, characterized in that: Also includes: The data display module is used to visualize the optical CT analog data collected by each DC control protection host and highlight the identified abnormal data.

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