Fault recording-based DC fault partition diagnosis alarm method and system

Abstract

The invention relates to the technical field of power systems, in particular to a DC fault partition diagnosis alarm method and system based on fault recording, and the method comprises the steps: obtaining the fault recording data of a DC power transmission system; monitoring a direct-current system fault based on the operation state of the direct-current power transmission system and a direct-current locking switch position signal in fault recording; distinguishing a polar region fault from a valve region fault according to a blocking signal source in fault recording, and isolating a fault region according to the determined fault type and position; and based on direct-current power, direct-current voltage and direct-current conditions in fault recording before and after a fault, distinguishing maintenance debugging and fault scenes, and giving an alarm and outputting a fault report by the system. Compared with the prior art, fault diagnosis and alarm of the direct-current power transmission system can be realized at the dispatching terminal only based on the fault recording data.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a DC fault zoning diagnosis and alarm method and system based on fault recording. Background Art

[0002] There are many types of faults in UHV / EHV DC transmission systems, and the fault locations are different. After a fault occurs, management, operation and maintenance, and support units at all levels have the need for rapid analysis and diagnosis and positioning, so as to quickly respond, report, and handle the fault, and further ensure the safe and stable operation of the power grid under the background of new power system construction.

[0003] At present, there are many DC technology solutions at home and abroad, including Siemens, ABB, NARI, Xuji, etc. The response results of the control and protection system to DC faults under different technical routes are also different. Existing technologies are mostly based on offline theoretical analysis based on theoretical simulation models, and analyze and identify the fault characteristics of different locations and types of UHV / UHV DC transmission systems. They are mostly used for DC protection principle design. The relevant conclusions need to be optimized and analyzed for specific projects. There is a lack of DC fault partition diagnosis and alarm technology solutions with wide applicability and fast response characteristics. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a DC fault zoning diagnosis and alarm method and system based on fault recording, which effectively solves the problems in the background technology.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: a DC fault zoning diagnosis and alarm method based on fault recording, comprising: Obtain fault recording data of DC transmission system; Monitor DC system faults based on the operating status of the DC transmission system and the DC blocking switch position signal in the fault recording data; According to the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault are distinguished, and the fault area is isolated according to the determined fault type and location; By analyzing the DC power, DC voltage, and DC current in the fault recording data before and after the fault, the maintenance and debugging scenarios can be distinguished from the actual fault scenarios. If the system determines through analysis that the current scenario is a real fault, the system will alarm and output a fault report, otherwise the system will not respond.

[0006] Furthermore, for UHVDC transmission systems, a symmetrical bipolar, dual-converter topology design is usually adopted; The sources of fault recording data include pole control recording, pole protection recording, converter control recording, converter protection recording, and converter transformer protection recording.

[0007] Furthermore, for UHV or HVDC transmission systems, a symmetrical bipolar or symmetrical monopolar, single converter design is usually adopted; The sources of fault recording data include pole control recording, pole protection recording, and converter transformer protection recording.

[0008] Furthermore, based on the operating status of the DC transmission system and the DC blocking switch position signal in the fault recording, the DC system fault is monitored, specifically: According to the blocking switch position signal, the DC transmission system fault, AC filter area fault and normal operation blocking are distinguished. The specific judgment process is as follows: (1) If the switch position signals of X-lock, Y-lock, and Z-lock change from 0 to 1, it is determined that a DC transmission system fault has occurred; otherwise, proceed to judgment criterion (2); (2) If the AC filter protection action switch position signal changes from 0 to 1, it is judged that an AC filter fault has occurred, causing the DC transmission system to be locked; otherwise, it is judged to be a normal operation lockout.

[0009] Furthermore, according to the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault are distinguished, and according to the determined fault type and location, the fault area is isolated, including: In the UHV DC transmission system, by analyzing the source of the blocking signal in the fault recording data, the pole area fault and valve area fault can be distinguished, specifically: UHV DC transmission systems usually adopt a symmetrical bipolar and dual converter topology design. If the protection action signal comes from the polar protection, it is judged that a polar area fault has occurred in the DC transmission system; If the protection action signal comes from the converter protection, it is determined that a valve area fault has occurred in the DC transmission system; For polar region faults, the DC line faults are distinguished from other polar region faults based on the presence of restart signals in the fault recording data; For valve area faults, the converter transformer faults are distinguished from other valve area faults based on the converter transformer protection action in the fault recording data.

[0010] Furthermore, according to the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault are distinguished, including: In the ultra-high voltage or high voltage direct current transmission system, by analyzing the source of the blocking signal in the fault recording data, it is possible to distinguish between the pole area fault and the valve area fault, specifically: Ultra-high voltage or high voltage direct current transmission systems usually adopt a symmetrical bipolar or symmetrical monopolar, single converter design, and do not specifically distinguish between pole area or valve area faults.

[0011] Furthermore, for polar region faults, the DC line faults are distinguished from other polar region faults based on the presence of restart signals in the fault recording data, including: UHV and EHV DC transmission systems have a restart logic after a DC line fault occurs. The restart logic will decide whether to perform a full-voltage restart, a reduced-voltage restart, or no restart based on the pre-fault operation mode, fault type, and fault duration of the DC transmission system. During the execution of the restart logic, the fault recording device records the corresponding signal changes. By analyzing the corresponding signals in the fault recording data during the execution of the restart logic, the DC line fault and other faults in the polar area are distinguished. The specific judgment method is as follows: If the fault recording data shows that the DC fault restart logic switch position signal changes from 0 to 1, it is judged that a DC line fault has occurred; otherwise, it is judged that other faults in the DC polar area have occurred.

[0012] Furthermore, for valve area faults, according to the converter transformer protection action in the fault recording data, the converter transformer fault is distinguished from other valve area faults, including: For valve area faults, if the fault recording data shows that the converter transformer protection action switch position signal changes from 0 to 1, and before the change occurs, no other type of protection action switch position signal changes from 0 to 1, then it is judged that a converter transformer fault has occurred; otherwise, it is judged to be other valve area faults.

[0013] Furthermore, by analyzing the DC power, DC voltage, and DC current in the fault recording data before and after the fault, the maintenance and debugging scenarios can be distinguished from the actual fault scenarios, including: During the maintenance and commissioning of the DC transmission system, once the DC protection related tests are carried out, the recording will be triggered. By analyzing the changes in DC power, DC voltage and DC current recorded by the fault recorder before and after the fault occurs, it is judged whether the current situation is a planned maintenance and commissioning or an unexpected real fault. The specific judgment process is as follows: Set the pre-fault state to about 100ms before the fault recording trigger signal changes from 0 to 1; In the first period, the DC transmission system transmission power is greater than or equal to 0.1 pu; During the second period, the DC voltage is higher than the minimum DC voltage of the DC transmission system; If both the first time period and the second time period are satisfied, it is determined that a real DC power transmission system fault has occurred; otherwise, it is determined that the DC power transmission system is in a maintenance and debugging state.

[0014] The present invention also provides a DC fault zone diagnosis and alarm system based on fault recording, comprising: A data acquisition module, used to acquire fault recording data of the DC transmission system; A fault monitoring module is used to monitor DC system faults based on the operating status of the DC transmission system and the DC blocking switch position signal in the fault recording data; The fault classification module is used to distinguish the pole area fault from the valve area fault according to the source of the blocking signal in the fault recording data, and isolate the fault area according to the determined fault type and location; The fault scenario judgment module is used to distinguish between maintenance and debugging and real fault scenarios by analyzing the DC power, DC voltage and DC current in the fault recording data before and after the fault; Alarm and report output module: if the system determines through analysis that the current scenario is a real fault, the system will alarm and output a fault report, otherwise the system will not respond.

[0015] Further, For UHVDC transmission systems, a symmetrical bipolar, dual-converter topology design is usually adopted; The sources of fault recording data include pole control recording, pole protection recording, converter control recording, converter protection recording, and converter transformer protection recording.

[0016] Further, For UHV or HVDC transmission systems, a symmetrical bipolar or symmetrical monopolar, single converter design is usually adopted; The sources of fault recording data include pole control recording, pole protection recording, and converter transformer protection recording.

[0017] Furthermore, the fault monitoring module is used to monitor the DC system fault based on the operating state of the DC power transmission system and the DC blocking switch position signal in the fault recording data, specifically: According to the blocking switch position signal, the DC transmission system fault, AC filter area fault and normal operation blocking are distinguished. The specific judgment process is as follows: (1) If the switch position signals of X-lock, Y-lock, and Z-lock change from 0 to 1, it is determined that a DC transmission system fault has occurred; otherwise, proceed to judgment criterion (2); (2) If the AC filter protection action switch position signal changes from 0 to 1, it is judged that an AC filter fault has occurred, causing the DC transmission system to be locked; otherwise, it is judged to be a normal operation lockout.

[0018] Furthermore, the fault classification module is used to distinguish between pole area faults and valve area faults according to the source of the locking signal in the fault recording data, and isolate the fault area according to the determined fault type and location, including: In the UHV DC transmission system, by analyzing the source of the blocking signal in the fault recording data, the pole area fault and valve area fault can be distinguished, specifically: UHV DC transmission systems usually adopt a symmetrical bipolar and dual converter topology design. If the protection action signal comes from the polar protection, it is judged that a polar area fault has occurred in the DC transmission system; If the protection action signal comes from the converter protection, it is determined that a valve area fault has occurred in the DC transmission system; For polar region faults, the DC line faults are distinguished from other polar region faults based on the presence of restart signals in the fault recording data; For valve area faults, the converter transformer faults are distinguished from other valve area faults based on the converter transformer protection action in the fault recording data.

[0019] Furthermore, the fault classification module is used to distinguish between pole area faults and valve area faults according to the source of the locking signal in the fault recording data, including: In the ultra-high voltage or high voltage direct current transmission system, by analyzing the source of the blocking signal in the fault recording data, it is possible to distinguish between the pole area fault and the valve area fault, specifically: Ultra-high voltage or high voltage direct current transmission systems usually adopt a symmetrical bipolar or symmetrical monopolar, single converter design, and do not specifically distinguish between pole area or valve area faults.

[0020] Furthermore, the polar region fault subdivision module is used to distinguish DC line faults from other polar region faults according to the presence of restart signals in the fault recording data for the polar region faults, including: UHV and EHV DC transmission systems have a restart logic after a DC line fault occurs. The restart logic will decide whether to perform a full-voltage restart, a reduced-voltage restart, or no restart based on the pre-fault operation mode, fault type, and fault duration of the DC transmission system. During the execution of the restart logic, the fault recording device records the corresponding signal changes. By analyzing the corresponding signals in the fault recording data during the execution of the restart logic, the DC line fault and other faults in the polar area are distinguished. The specific judgment method is as follows: If the fault recording data shows that the DC fault restart logic switch position signal changes from 0 to 1, it is judged that a DC line fault has occurred; otherwise, it is judged that other faults in the DC polar area have occurred.

[0021] Furthermore, the valve area fault subdivision module is used to distinguish the converter transformer fault from other valve area faults according to the converter transformer protection action in the fault recording data for the valve area fault, including: For valve area faults, if the fault recording data shows that the converter transformer protection action switch position signal changes from 0 to 1, and before the change occurs, no other type of protection action switch position signal changes from 0 to 1, then it is judged that a converter transformer fault has occurred; otherwise, it is judged to be other valve area faults.

[0022] Furthermore, the fault scenario judgment module is used to distinguish between maintenance and debugging and real fault scenarios by analyzing the DC power, DC voltage and DC current in the fault recording data before and after the fault, including: During the maintenance and commissioning of the DC transmission system, once the DC protection related tests are carried out, the recording will be triggered. By analyzing the changes in DC power, DC voltage and DC current recorded by the fault recorder before and after the fault occurs, it is judged whether the current situation is a planned maintenance and commissioning or an unexpected real fault. The specific judgment process is as follows: Set the pre-fault state to about 100ms before the fault recording trigger signal changes from 0 to 1; In the first period, the DC transmission system transmission power is greater than or equal to 0.1 pu; During the second period, the DC voltage is higher than the minimum DC voltage of the DC transmission system; If both the first time period and the second time period are satisfied, it is determined that a real DC power transmission system fault has occurred; otherwise, it is determined that the DC power transmission system is in a maintenance and debugging state.

[0023] The present invention further provides an electronic device, comprising: Processor and memory; The processor is used to execute the steps of the DC fault zoning diagnosis and alarm method based on fault recording by calling the program or instruction stored in the memory.

[0024] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a program or instruction, wherein the program or instruction is a step for a computer to execute the DC fault partition diagnosis and alarm method.

[0025] The beneficial effects of the present invention are as follows: the present invention can quickly and accurately locate faults in the pole area, valve area, converter area, and AC filter area based on key switch displacement information in the fault recording data and the DC operation mode before the fault, and realize real-time reporting to the dispatching center after the fault.

[0026] The present invention does not rely on the logic or simulation calculation of the DC control protection program, but directly performs fault diagnosis based on the actual engineering recording, and has real-time performance. The proposed fault diagnosis logic is applicable to most current DC technical routes and has wide applicability. The DC fault zoning diagnosis and alarm process does not involve personnel and has analysis independence. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1It is a flow chart of a DC fault zoning diagnosis and alarm method based on fault recording in an embodiment of the present invention; Figure 2 This is a flow chart of fault zone diagnosis and alarm of a UHV DC transmission system according to an embodiment of the present invention; Figure 3 This is a flow chart of fault zone diagnosis and alarm of an ultra-high voltage / high voltage direct current transmission system in an embodiment of the present invention; DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0030] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. 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. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0032] like Figure 1 and Figure 2 The DC fault zoning diagnosis and alarm method based on fault recording is shown for a UHV DC transmission system, and includes: Obtain fault recording data of the DC transmission system; fault recording data is a series of electrical quantities recorded when a DC transmission system fails, including voltage, current, power and other parameters. These data are crucial for subsequent fault analysis.

[0033] For UHV DC transmission systems, a symmetrical bipolar, dual-converter topology design is usually adopted; each pole has an independent converter to improve the transmission capacity and reliability of the system.

[0034] The sources of fault recording data include pole control recording (recorded as PCP), pole protection recording (recorded as PPR), converter control recording (recorded as CCP), converter protection recording (recorded as CPR), and converter transformer protection recording.

[0035] The pole control recording is used to monitor and control the operating status of the pole, and the pole protection recording is used to protect the pole from faults; the converter control recording is used to monitor and control the operating status of the converter; the converter protection recording is used to protect the converter from faults; and the converter transformer protection recording is used to protect the converter transformer from faults.

[0036] Monitor DC system faults based on the operating status of the DC transmission system and the DC blocking switch position signal in the fault recording data; According to the blocking switch position signal, the DC transmission system fault, AC filter area fault and normal operation blocking are distinguished. The specific judgment process is as follows: (1) If the switch position signals of X-lock, Y-lock, and Z-lock change from 0 to 1, it is determined that a DC transmission system fault has occurred; otherwise, proceed to judgment criterion (2); (2) If the AC filter protection action switch position signal changes from 0 to 1, it is judged that an AC filter fault has occurred, causing the DC transmission system to be locked; otherwise, it is judged to be a normal operation lockout.

[0037] In a DC transmission system, a blocking switch is a protection mechanism. When the system detects certain abnormal conditions, such as overcurrent, overvoltage or other faults, the blocking switch will be activated to cut off the current to protect the system from damage. The blocking switch position signal refers to the state of the blocking switch, which indicates whether the blocking switch has been activated.

[0038] DC transmission system fault judgment quickly identifies whether a fault has occurred in the DC transmission system so that timely measures can be taken to isolate the faulty part and prevent the fault from spreading and affecting the entire system; while AC filter area fault judgment accurately locates whether the fault has occurred in the AC filter area, which is crucial for taking targeted maintenance measures and also helps to protect other parts of the DC transmission system from damage; if neither of the above two conditions is met, that is, no DC system fault lockout signal is detected, and no AC filter area fault signal is detected, then it can be determined as normal operation lockout.

[0039] The above logic judgment process can quickly and accurately distinguish different types of lockout events, so that corresponding measures can be taken. For real fault conditions, the faulty part can be quickly isolated and repaired to reduce the impact on the entire system; and for normal operation lockout, unnecessary emergency response can be avoided to ensure smooth operation.

[0040] This step is to determine whether the system has a fault by analyzing the DC blocking switch position signal in the fault recording data. The DC blocking switch position signal is a signal that indicates whether the system is in normal operation. If this signal indicates that the system has been blocked, then it can be confirmed that a fault has occurred.

[0041] According to the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault are distinguished, and the fault area is isolated according to the determined fault type and location; In the UHV DC transmission system, by analyzing the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault can be distinguished, and the fault area can be isolated according to the determined fault type and location, specifically: UHVDC transmission systems usually adopt a symmetrical bipolar and dual converter topology design. If the protection action signal comes from the pole protection PPR, it is judged that a pole area fault has occurred in the DC transmission system; If the protection action signal comes from the converter protection CPR, it is determined that a valve area fault has occurred in the DC transmission system.

[0042] By analyzing the fault recording data to identify and locate the fault, and further analyzing the source of the lockout signal, the specific area where the fault occurs can be located more accurately, narrowing the range of possible locations where the fault may occur, whether it is the pole area or the valve area, which is crucial for subsequent maintenance and system recovery.

[0043] For polar region faults, the DC line faults are distinguished from other polar region faults based on the presence of restart signals in the fault recording data, including: UHV and EHV DC transmission systems have a restart logic after a DC line fault occurs. The restart logic will decide whether to perform a full-voltage restart, a reduced-voltage restart, or no restart based on the pre-fault operation mode, fault type, and fault duration of the DC transmission system. The restart logic is part of the system design and is used to guide the recovery operation after a fault. The decision of the restart logic is based on three main factors: the operating mode before the fault: whether the system was in full-pressure operation or reduced-pressure operation before the fault occurred, etc.; the fault type: the nature of the fault, such as whether it is a transient fault or a continuous fault, a polar area fault or a valve area fault, etc.; the fault duration: how long the fault lasts, which will affect the choice of the restart strategy.

[0044] Based on the three main factors mentioned above, the restart logic will decide to take one of the following actions: Full voltage restart: the system resumes normal operation at full voltage after the fault is cleared; Reduced voltage restart: the system gradually resumes normal operation at a reduced voltage after the fault is cleared; No restart: In some cases, it may be decided not to restart immediately, but to conduct further inspections or wait.

[0045] During the execution of the restart logic, the fault recording device records the corresponding signal changes. By analyzing the corresponding signals in the fault recording data during the execution of the restart logic, the DC line fault and other faults in the polar area are distinguished. The specific judgment method is as follows: If the fault recording data shows that the DC fault restart logic switch position signal (usually the RESTART signal) changes from 0 to 1, it is judged that a DC line fault has occurred; otherwise, it is judged that other faults in the DC polar area have occurred.

[0046] During the execution of the restart logic, the fault recording device will record the changes in key electrical signals, including but not limited to voltage, current, power, etc., as well as specific switch position signals related to the restart logic.

[0047] For valve area faults, the converter transformer faults are distinguished from other valve area faults according to the converter transformer protection action in the fault recording data, including: For valve area faults, if the fault recording data shows that the converter transformer protection action switch position signal changes from 0 to 1, and before the change occurs, no other type of protection action switch position signal changes from 0 to 1, then it is judged that a converter transformer fault has occurred; otherwise, it is judged to be other valve area faults.

[0048] Valve area fault refers to faults that occur inside the converter station, especially those related to the converter. In valve area faults, the specific fault type is identified by monitoring the switch position signal of the converter transformer protection action in the fault recording data, and the converter transformer protection action refers to the protection mechanism triggered when the protection system detects that there may be a problem with the converter transformer.

[0049] When the converter transformer protection action signal changes and there is no other protection action before, it is judged as a converter transformer fault. If the above two conditions cannot be met at the same time, the fault is judged to be other faults in the valve area.

[0050] If the fault is determined to be a pole zone fault, then this step is to determine whether the fault occurred in the DC line or in other parts of the pole zone by analyzing the restart signal in the fault recording data. The presence or absence of the restart signal can help further determine the specific type of fault. Similarly, if the fault is determined to be a valve zone fault, this step is to distinguish whether the fault occurred in the converter transformer itself or in other parts of the valve zone by analyzing the action of the converter transformer protection. The action of the converter transformer protection is a signal indicating whether the converter transformer is working properly.

[0051] By analyzing the DC power, DC voltage, and DC current in the fault recording data before and after the fault, the maintenance and debugging scenarios can be distinguished from the actual fault scenarios. During the maintenance and commissioning of the DC transmission system, once the DC protection related tests are carried out, the recording will be triggered. By analyzing the changes in DC power, DC voltage and DC current recorded by the fault recorder before and after the fault occurs, it is judged whether the current situation is a planned maintenance and commissioning or an unexpected real fault. The specific judgment process is as follows: Fault recording trigger signal setting: Set the pre-fault time to about 100ms before the fault recording trigger signal changes from 0 to 1; First period condition: In the first period, the DC transmission system transmission power is greater than or equal to 0.1pu; Second period condition: During the second period, the DC voltage is higher than the minimum DC voltage of the DC transmission system; If both the first time period and the second time period are satisfied, it is determined that a real DC power transmission system fault has occurred; otherwise, it is determined that the DC power transmission system is in a maintenance and debugging state.

[0052] This method based on fault recording data analysis helps to accurately distinguish between planned maintenance and debugging and real faults, thereby ensuring the stability and reliability of the system. At the same time, it also reduces unnecessary emergency responses caused by misjudgment and improves operation and maintenance efficiency.

[0053] If the system determines through analysis that the current scenario is a real fault, the system will alarm and output a fault report, otherwise the system will not respond.

[0054] By comparing the DC power, voltage and current data before and after the fault, it can be distinguished whether it is a normal maintenance and debugging or a real fault scenario. If it is confirmed to be a fault, the system will issue an alarm and output a fault report so that relevant personnel can take appropriate measures.

[0055] This method is based on actual fault recording data, making the decision-making process more data-driven, reducing interference from human factors, and improving the accuracy of decision-making. By gradually analyzing the fault recording data, the type and location of the fault can be determined. The area where the fault occurred (pole area or valve area) or even specific equipment (such as converter transformer) can be accurately located, which helps to quickly take targeted maintenance measures, improves the efficiency and accuracy of fault handling in the DC transmission system, and is of great significance for ensuring the stable operation of the power system.

[0056] like Figure 1 and Figure 3 The DC fault zoning diagnosis and alarm method based on fault recording is aimed at the ultra-high voltage / high voltage DC transmission system, and includes: Obtain fault recording data of the DC transmission system; fault recording data is a series of electrical quantities recorded when a DC transmission system fails, including voltage, current, power and other parameters. These data are crucial for subsequent fault analysis.

[0057] For ultra-high voltage or high voltage direct current transmission systems, a symmetrical bipolar or symmetrical monopolar, single converter design is usually adopted; each pole may have one or two converters, which is suitable for transmission needs at lower voltage levels.

[0058] The sources of fault recording data include pole control recording PCP, pole protection recording PPR, and converter transformer protection recording. Pole control recording monitors and controls the operating status of the pole, pole protection recording protects the pole from faults, and converter transformer protection recording protects the converter transformer from faults.

[0059] Monitor DC system faults based on the operating status of the DC transmission system and the DC blocking switch position signal in the fault recording data; According to the blocking switch position signal, the DC transmission system fault, AC filter area fault and normal operation blocking are distinguished. The specific judgment process is as follows: (1) If the switch position signals of X-lock, Y-lock, and Z-lock change from 0 to 1, it is determined that a DC transmission system fault has occurred; otherwise, proceed to judgment criterion (2); (2) If the AC filter protection action switch position signal changes from 0 to 1, it is judged that an AC filter fault has occurred, causing the DC transmission system to be locked; otherwise, it is judged to be a normal operation lockout.

[0060] In a DC transmission system, a blocking switch is a protection mechanism. When the system detects certain abnormal conditions, such as overcurrent, overvoltage or other faults, the blocking switch will be activated to cut off the current to protect the system from damage. The blocking switch position signal refers to the state of the blocking switch, which indicates whether the blocking switch has been activated.

[0061] DC transmission system fault judgment quickly identifies whether a fault has occurred in the DC transmission system so that timely measures can be taken to isolate the faulty part and prevent the fault from spreading and affecting the entire system; while AC filter area fault judgment accurately locates whether the fault has occurred in the AC filter area, which is crucial for taking targeted maintenance measures and also helps to protect other parts of the DC transmission system from damage; if neither of the above two conditions is met, that is, no DC system fault lockout signal is detected, and no AC filter area fault signal is detected, then it can be determined as normal operation lockout.

[0062] The above logic judgment process can quickly and accurately distinguish different types of lockout events, so that corresponding measures can be taken. For real fault conditions, the faulty part can be quickly isolated and repaired to reduce the impact on the entire system; and for normal operation lockout, unnecessary emergency response can be avoided to ensure smooth operation.

[0063] This step is to determine whether the system has a fault by analyzing the DC blocking switch position signal in the fault recording data. The DC blocking switch position signal is a signal that indicates whether the system is in normal operation. If this signal indicates that the system has been blocked, then it can be confirmed that a fault has occurred.

[0064] According to the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault are distinguished, and the fault area is isolated according to the determined fault type and location; In the ultra-high voltage or high voltage direct current transmission system, by analyzing the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault can be distinguished, and the fault area can be isolated according to the determined fault type and location, specifically: Ultra-high voltage or high voltage direct current transmission systems usually adopt a symmetrical bipolar or symmetrical monopolar, single converter design, and do not specifically distinguish between pole area or valve area faults.

[0065] Even if there is no special distinction between pole area or valve area faults, the approximate location of the fault can still be determined by analyzing the source of the locking signal, so that the fault can be handled more specifically, which helps to reduce the time of troubleshooting and improve processing efficiency.

[0066] For polar region faults, the DC line faults are distinguished from other polar region faults based on the presence of restart signals in the fault recording data, including: UHV and EHV DC transmission systems have a restart logic after a DC line fault occurs. The restart logic will decide whether to perform a full-voltage restart, a reduced-voltage restart, or no restart based on the pre-fault operation mode, fault type, and fault duration of the DC transmission system. The restart logic is part of the system design and is used to guide the recovery operation after a fault. The decision of the restart logic is based on three main factors: the operating mode before the fault: whether the system was in full-pressure operation or reduced-pressure operation before the fault occurred, etc.; the fault type: the nature of the fault, such as whether it is a transient fault or a continuous fault, a polar area fault or a valve area fault, etc.; the fault duration: how long the fault lasts, which will affect the choice of the restart strategy.

[0067] Based on the three main factors mentioned above, the restart logic will decide to take one of the following actions: Full voltage restart: the system resumes normal operation at full voltage after the fault is cleared; Reduced voltage restart: the system gradually resumes normal operation at a reduced voltage after the fault is cleared; No restart: In some cases, it may be decided not to restart immediately, but to conduct further inspections or wait.

[0068] During the execution of the restart logic, the fault recording device records the corresponding signal changes. By analyzing the corresponding signals in the fault recording data during the execution of the restart logic, the DC line fault and other faults in the polar area are distinguished. The specific judgment method is as follows: If the fault recording data shows that the DC fault restart logic switch position signal (usually the RESTART signal) changes from 0 to 1, it is judged that a DC line fault has occurred; otherwise, it is judged that other faults in the DC polar area have occurred.

[0069] During the execution of the restart logic, the fault recording device will record the changes in key electrical signals, including but not limited to voltage, current, power, etc., as well as specific switch position signals related to the restart logic.

[0070] If the fault is determined to be a polar zone fault, then the next step is to determine whether the fault occurred in the DC line or in another part of the polar zone by analyzing the restart signal in the fault recording data. The presence or absence of the restart signal can help further determine the specific type of fault.

[0071] For valve area faults, the faults of the converter transformers are distinguished from other faults in the valve area according to the protection action of the converter transformers in the fault recording data, including: For valve area faults, if the fault recording data shows that the converter transformer protection action switch position signal changes from 0 to 1, and before the change occurs, no other type of protection action switch position signal changes from 0 to 1, then it is judged that a converter transformer fault has occurred; otherwise, it is judged to be other valve area faults.

[0072] Valve area fault refers to faults that occur inside the converter station, especially those related to the converter. In valve area faults, the specific fault type is identified by monitoring the switch position signal of the converter transformer protection action in the fault recording data, and the converter transformer protection action refers to the protection mechanism triggered when the protection system detects that there may be a problem with the converter transformer.

[0073] When the converter transformer protection action signal changes and there is no other protection action before, it is judged as a converter transformer fault. If the above two conditions cannot be met at the same time, the fault is judged to be other faults in the valve area.

[0074] Similarly, if the fault is determined to be a valve zone fault, this step is to distinguish whether the fault occurs in the converter transformer itself or in other parts of the valve zone by analyzing the action of the converter transformer protection. The action of the converter transformer protection is a signal indicating whether the converter transformer is operating normally.

[0075] By analyzing the DC power, DC voltage, and DC current in the fault recording data before and after the fault, the maintenance and debugging scenarios can be distinguished from the actual fault scenarios. During the maintenance and commissioning of the DC transmission system, once the DC protection related tests are carried out, the recording will be triggered. By analyzing the changes in DC power, DC voltage and DC current recorded by the fault recorder before and after the fault occurs, it is judged whether the current situation is a planned maintenance and commissioning or an unexpected real fault. The specific judgment process is as follows: Fault recording trigger signal setting: Set the pre-fault time to about 100ms before the fault recording trigger signal changes from 0 to 1; First period condition: In the first period, the DC transmission system transmission power is greater than or equal to 0.1pu; Second period condition: During the second period, the DC voltage is higher than the minimum DC voltage of the DC transmission system; If both the first time period and the second time period are satisfied, it is determined that a real DC power transmission system fault has occurred; otherwise, it is determined that the DC power transmission system is in a maintenance and debugging state.

[0076] This method based on fault recording data analysis helps to accurately distinguish between planned maintenance and debugging and real faults, thereby ensuring the stability and reliability of the system. At the same time, it also reduces unnecessary emergency responses caused by misjudgment and improves operation and maintenance efficiency.

[0077] If the system determines through analysis that the current scenario is a real fault, the system will alarm and output a fault report, otherwise the system will not respond.

[0078] By comparing the DC power, voltage and current data before and after the fault, it can be distinguished whether it is a normal maintenance and debugging or a real fault scenario. If it is confirmed to be a fault, the system will issue an alarm and output a fault report so that relevant personnel can take appropriate measures.

[0079] This method is based on actual fault recording data, making the decision-making process more data-driven, reducing interference from human factors, and improving the accuracy of decision-making. By gradually analyzing the fault recording data, the type and location of the fault can be determined. The area where the fault occurred (pole area or valve area) or even specific equipment (such as converter transformer) can be accurately located, which helps to quickly take targeted maintenance measures, improves the efficiency and accuracy of fault handling in the DC transmission system, and is of great significance for ensuring the stable operation of the power system.

[0080] The present invention also provides a DC fault zone diagnosis and alarm system based on fault recording, comprising: A data acquisition module, used to acquire fault recording data of the DC transmission system; A fault monitoring module is used to monitor DC system faults based on the operating status of the DC transmission system and the DC blocking switch position signal in the fault recording data; The fault classification module is used to distinguish the pole area fault from the valve area fault according to the source of the blocking signal in the fault recording data, and isolate the fault area according to the determined fault type and location; The fault scenario judgment module is used to distinguish between maintenance and debugging and real fault scenarios by analyzing the DC power, DC voltage and DC current in the fault recording data before and after the fault; Alarm and report output module: if the system determines through analysis that the current scenario is a real fault, the system will alarm and output a fault report, otherwise the system will not respond.

[0081] In the preferred scheme, for the UHV DC transmission system, a symmetrical bipolar, dual-converter topology design is usually adopted; The sources of fault recording data include pole control recording, pole protection recording, converter control recording, converter protection recording, and converter transformer protection recording.

[0082] In another preferred embodiment, for an ultra-high voltage or high voltage direct current transmission system, a symmetrical bipolar or symmetrical monopolar, single converter design is generally adopted; The sources of fault recording data include pole control recording, pole protection recording, and converter transformer protection recording.

[0083] In the preferred embodiment of the present invention, the fault monitoring module is used to monitor the DC system fault based on the operating state of the DC power transmission system and the DC blocking switch position signal in the fault recording data, specifically: According to the blocking switch position signal, the DC transmission system fault, AC filter area fault and normal operation blocking are distinguished. The specific judgment process is as follows: (1) If the switch position signals of X-lock, Y-lock, and Z-lock change from 0 to 1, it is determined that a DC transmission system fault has occurred; otherwise, proceed to judgment criterion (2); (2) If the AC filter protection action switch position signal changes from 0 to 1, it is judged that an AC filter fault has occurred, causing the DC transmission system to be locked; otherwise, it is judged to be a normal operation lockout.

[0084] In a preferred embodiment of the present invention, the fault classification module is used to distinguish between pole area faults and valve area faults according to the source of the locking signal in the fault recording data, and isolate the fault area according to the determined fault type and location, including: In the UHV DC transmission system, by analyzing the source of the blocking signal in the fault recording data, the pole area fault and valve area fault can be distinguished, specifically: UHV DC transmission systems usually adopt a symmetrical bipolar and dual converter topology design. If the protection action signal comes from the polar protection, it is judged that a polar area fault has occurred in the DC transmission system; If the protection action signal comes from the converter protection, it is determined that a valve area fault has occurred in the DC transmission system; For polar region faults, the DC line faults are distinguished from other polar region faults based on the presence of restart signals in the fault recording data; For valve area faults, distinguish between converter transformer faults and other valve area faults based on the converter transformer protection action in the fault recording data; In a preferred embodiment, the fault classification module is used to distinguish between pole area faults and valve area faults according to the source of the locking signal in the fault recording data, and includes: In the ultra-high voltage or high voltage direct current transmission system, by analyzing the source of the blocking signal in the fault recording data, it is possible to distinguish between the pole area fault and the valve area fault, specifically: Ultra-high voltage or high voltage direct current transmission systems usually adopt a symmetrical bipolar or symmetrical monopolar, single converter design, and do not specifically distinguish between pole area or valve area faults.

[0085] In another preferred solution, for the polar region fault, the DC line fault is distinguished from other polar region faults according to the presence of the restart signal in the fault recording data, including: UHV and EHV DC transmission systems have a restart logic after a DC line fault occurs. The restart logic will decide whether to perform a full-voltage restart, a reduced-voltage restart, or no restart based on the pre-fault operation mode, fault type, and fault duration of the DC transmission system. During the execution of the restart logic, the fault recording device records the corresponding signal changes. By analyzing the corresponding signals in the fault recording data during the execution of the restart logic, the DC line fault and other faults in the polar area are distinguished. The specific judgment method is as follows: If the fault recording data shows that the DC fault restart logic switch position signal changes from 0 to 1, it is judged that a DC line fault has occurred; otherwise, it is judged that other faults in the DC polar area have occurred.

[0086] In a preferred embodiment of the present invention, for a valve area fault, the converter transformer fault is distinguished from other valve area faults according to the converter transformer protection action in the fault recording data, including: For valve area faults, if the fault recording data shows that the converter transformer protection action switch position signal changes from 0 to 1, and before the change occurs, no other type of protection action switch position signal changes from 0 to 1, then it is judged that a converter transformer fault has occurred; otherwise, it is judged to be other valve area faults.

[0087] In a preferred embodiment of the present invention, the fault scenario judgment module is used to distinguish between maintenance and debugging and real fault scenarios by analyzing the DC power, DC voltage and DC current in the fault recording data before and after the fault, and includes: During the maintenance and commissioning of the DC transmission system, once the DC protection related tests are carried out, the recording will be triggered. By analyzing the changes in DC power, DC voltage and DC current recorded by the fault recorder before and after the fault occurs, it is judged whether the current situation is a planned maintenance and commissioning or an unexpected real fault. The specific judgment process is as follows: Set the pre-fault state to about 100ms before the fault recording trigger signal changes from 0 to 1; In the first period, the DC transmission system transmission power is greater than or equal to 0.1 pu; During the second period, the DC voltage is higher than the minimum DC voltage of the DC transmission system.

[0088] If both the first time period and the second time period are satisfied, it is determined that a real DC power transmission system fault has occurred; otherwise, it is determined that the DC power transmission system is in a maintenance and debugging state.

[0089] The present invention also provides an electronic device, the electronic device comprising: a processor and a memory; the processor, by calling the program or instruction stored in the memory, is used to execute the steps of the DC fault partition diagnosis alarm method, the steps comprising obtaining DC transmission system fault recording data; based on the DC transmission system operation state and the DC blocking switch position signal in the fault recording data, monitoring the DC system fault; according to the source of the blocking signal in the fault recording data, distinguishing the pole area fault from the valve area fault, and isolating the fault area according to the determined fault type and location; by analyzing the DC power, DC voltage and DC current in the fault recording data before and after the fault, distinguishing the maintenance and debugging from the real fault scene; if the system determines that the current scene is a real fault through analysis, the system alarms and outputs a fault report, otherwise the system does not respond. The present invention quickly and accurately locates the faults of the pole area, valve area, converter area and AC filter area based on the key switch position information in the fault recording data and the DC operation mode before the fault, and realizes real-time reporting to the dispatching center after the fault. Compared with the existing technology, the DC transmission system fault diagnosis alarm can be realized at the dispatching terminal based only on the fault recording data.

[0090] The present invention also provides a computer-readable storage medium, the computer-readable storage medium stores a program or instruction, the program or instruction is a step of a computer executing a DC fault partition diagnosis alarm method, the step includes obtaining DC transmission system fault recording data; based on the DC transmission system operation state and the DC locking switch position signal in the fault recording data, monitoring the DC system fault; according to the source of the locking signal in the fault recording data, distinguishing the pole area fault from the valve area fault, and isolating the fault area according to the determined fault type and location; by analyzing the DC power, DC voltage and DC current in the fault recording data before and after the fault, distinguishing the maintenance and debugging from the real fault scene; if the system determines that the current scene is a real fault through analysis, the system alarms and outputs a fault report, otherwise the system does not respond. The present invention quickly and accurately locates the faults of the pole area, valve area, converter area, and AC filter area based on the key switch displacement information in the fault recording data and the DC operation mode before the fault, and realizes real-time reporting to the dispatching center after the fault. Compared with the existing technology, the DC transmission system fault diagnosis alarm can be realized at the dispatching terminal based only on the fault recording data.

[0091] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes. The schemes in the embodiments of the present application may be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0092] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0093] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0094] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0095] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0096] Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A DC fault zoning diagnosis and alarm method based on fault recording, characterized in that: include: Obtain fault recording data of DC transmission system; Monitor DC system faults based on the operating status of the DC transmission system and the DC blocking switch position signal in the fault recording data; According to the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault are distinguished, and the fault area is isolated according to the determined fault type and location; By analyzing the DC power, DC voltage, and DC current in the fault recording data before and after the fault, the maintenance and debugging scenarios can be distinguished from the actual fault scenarios. If the system determines through analysis that the current scenario is a real fault, the system will alarm and output a fault report, otherwise the system will not respond.

2. The DC fault zoning diagnosis and alarm method based on fault recording according to claim 1 is characterized in that: For UHVDC transmission systems, a symmetrical bipolar, dual-converter topology design is usually adopted; The sources of fault recording data include pole control recording, pole protection recording, converter control recording, converter protection recording, and converter transformer protection recording.

3. The DC fault zoning diagnosis and alarm method based on fault recording according to claim 1 is characterized in that: For UHV or HVDC transmission systems, a symmetrical bipolar or symmetrical monopolar, single converter design is usually adopted; The sources of fault recording data include pole control recording, pole protection recording, and converter transformer protection recording.

4. The DC fault zoning diagnosis and alarm method based on fault recording according to claim 1 is characterized in that: Based on the operating status of the DC transmission system and the DC blocking switch position signal in the fault recording data, the DC system faults are monitored, specifically: According to the blocking switch position signal, the DC transmission system fault, AC filter area fault and normal operation blocking are distinguished. The specific judgment process is as follows: (1) If the switch position signals of X-lock, Y-lock, and Z-lock change from 0 to 1, it is determined that a DC transmission system fault has occurred; otherwise, proceed to judgment criterion (2); (2) If the AC filter protection action switch position signal changes from 0 to 1, it is judged that an AC filter fault has occurred, causing the DC transmission system to be locked; otherwise, it is judged to be a normal operation lockout.

5. The DC fault zoning diagnosis and alarm method based on fault recording according to claim 1 is characterized in that: According to the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault are distinguished, and the fault area is isolated according to the determined fault type and location, including: In the UHV DC transmission system, by analyzing the source of the blocking signal in the fault recording data, the pole area fault and valve area fault can be distinguished, specifically: UHV DC transmission systems usually adopt a symmetrical bipolar and dual converter topology design. If the protection action signal comes from the polar protection, it is judged that a polar area fault has occurred in the DC transmission system; If the protection action signal comes from the converter protection, it is determined that a valve area fault has occurred in the DC transmission system; For polar region faults, the DC line faults are distinguished from other polar region faults based on the presence of restart signals in the fault recording data; For valve area faults, the converter transformer faults are distinguished from other valve area faults based on the converter transformer protection action in the fault recording data.

6. The DC fault zoning diagnosis and alarm method based on fault recording according to claim 1 is characterized in that: According to the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault are distinguished, including: In the ultra-high voltage or high voltage direct current transmission system, by analyzing the source of the blocking signal in the fault recording data, it is possible to distinguish between the pole area fault and the valve area fault, specifically: Ultra-high voltage or high voltage direct current transmission systems usually adopt a symmetrical bipolar or symmetrical monopolar, single converter design, and do not specifically distinguish between pole area or valve area faults.

7. The DC fault zoning diagnosis and alarm method based on fault recording according to claim 5 is characterized in that: For polar region faults, the DC line faults are distinguished from other polar region faults based on the presence of restart signals in the fault recording data, including: UHV and EHV DC transmission systems have a restart logic after a DC line fault occurs. The restart logic will decide whether to perform a full-voltage restart, a reduced-voltage restart, or no restart based on the pre-fault operation mode, fault type, and fault duration of the DC transmission system. During the execution of the restart logic, the fault recording device records the corresponding signal changes. By analyzing the corresponding signals in the fault recording data during the execution of the restart logic, the DC line fault and other faults in the polar area are distinguished. The specific judgment method is as follows: If the fault recording data shows that the DC fault restart logic switch bit signal changes from 0 to 1, it is judged that a DC line fault has occurred; otherwise, it is judged that other faults in the DC polar area have occurred.

8. The DC fault zoning diagnosis and alarm method based on fault recording according to claim 5 is characterized in that: For valve area faults, the faults of the converter transformers are distinguished from other faults in the valve area according to the protection action of the converter transformers in the fault recording data, including: For valve area faults, if the fault recording data shows that the converter transformer protection action switch position signal changes from 0 to 1, and before the change occurs, no other type of protection action switch position signal changes from 0 to 1, then it is judged that a converter transformer fault has occurred; otherwise, it is judged to be other valve area faults.

9. The DC fault zoning diagnosis and alarm method based on fault recording according to claim 1 is characterized in that: By analyzing the DC power, DC voltage, and DC current in the fault recording data before and after the fault, the maintenance and debugging scenarios can be distinguished from the actual fault scenarios, including: During the maintenance and commissioning of the DC transmission system, once the DC protection related tests are carried out, the recording will be triggered. By analyzing the changes in DC power, DC voltage and DC current recorded by the fault recorder before and after the fault occurs, it is judged whether the current situation is a planned maintenance and commissioning or an unexpected real fault. The specific judgment process is as follows: Set the pre-fault state to about 100ms before the fault recording trigger signal changes from 0 to 1; In the first period, the DC transmission system transmission power is greater than or equal to 0.1 pu; During the second period, the DC voltage is higher than the minimum DC voltage of the DC transmission system; If both the first time period and the second time period are satisfied, it is determined that a real DC power transmission system fault has occurred; otherwise, it is determined that the DC power transmission system is in a maintenance and debugging state.

10. A DC fault zone diagnosis and alarm system based on fault recording, characterized in that: include A data acquisition module, used to acquire fault recording data of the DC transmission system; A fault monitoring module is used to monitor DC system faults based on the operating status of the DC transmission system and the DC blocking switch position signal in the fault recording data; The fault classification module is used to distinguish the pole area fault from the valve area fault according to the source of the blocking signal in the fault recording data, and isolate the fault area according to the determined fault type and location; The fault scenario judgment module is used to distinguish between maintenance and debugging and real fault scenarios by analyzing the DC power, DC voltage and DC current in the fault recording data before and after the fault; Alarm and report output module: if the system determines through analysis that the current scenario is a real fault, the system will alarm and output a fault report, otherwise the system will not respond.

11. The DC fault zoning diagnosis and alarm system based on fault recording according to claim 10, characterized in that: For UHVDC transmission systems, a symmetrical bipolar, dual-converter topology design is usually adopted; The sources of fault recording data include pole control recording, pole protection recording, converter control recording, converter protection recording, and converter transformer protection recording.

12. The DC fault zoning diagnosis and alarm system based on fault recording according to claim 10, characterized in that: For UHV or HVDC transmission systems, a symmetrical bipolar or symmetrical monopolar, single converter design is usually adopted; The sources of fault recording data include pole control recording, pole protection recording, and converter transformer protection recording.

13. The DC fault zoning diagnosis and alarm system based on fault recording according to claim 10, characterized in that: The fault detection module is used to monitor the DC system fault based on the operating status of the DC power transmission system and the DC blocking switch position signal in the fault recording data, specifically: According to the blocking switch position signal, the DC transmission system fault, AC filter area fault and normal operation blocking are distinguished. The specific judgment process is as follows: (1) If the switch position signals of X-lock, Y-lock, and Z-lock change from 0 to 1, it is determined that a DC transmission system fault has occurred; otherwise, proceed to judgment criterion (2); (2) If the AC filter protection action switch position signal changes from 0 to 1, it is judged that an AC filter fault has occurred, causing the DC transmission system to be locked; otherwise, it is judged to be a normal operation lockout.

14. The DC fault zoning diagnosis and alarm system based on fault recording according to claim 10, characterized in that: The fault classification module is used to distinguish between pole area faults and valve area faults according to the source of the locking signal in the fault recording data, and includes: In the UHV DC transmission system, by analyzing the source of the blocking signal in the fault recording data, the pole area fault and the valve area fault are distinguished, and according to the determined fault type and location, the fault area is isolated as follows: UHV DC transmission systems usually adopt a symmetrical bipolar and dual converter topology design. If the protection action signal comes from the polar protection, it is judged that a polar area fault has occurred in the DC transmission system; If the protection action signal comes from the converter protection, it is determined that a valve area fault has occurred in the DC transmission system; For polar region faults, the DC line faults are distinguished from other polar region faults based on the presence of restart signals in the fault recording data; For valve area faults, the converter transformer faults are distinguished from other valve area faults based on the converter transformer protection action in the fault recording data.

15. The DC fault zoning diagnosis and alarm system based on fault recording according to claim 10, characterized in that: The fault classification module is used to distinguish between pole area faults and valve area faults according to the source of the locking signal in the fault recording data, and includes: In the ultra-high voltage or high voltage direct current transmission system, by analyzing the source of the blocking signal in the fault recording data, it is possible to distinguish between the pole area fault and the valve area fault, specifically: Ultra-high voltage or high voltage direct current transmission systems usually adopt a symmetrical bipolar or symmetrical monopolar, single converter design, and do not specifically distinguish between pole area or valve area faults.

16. The DC fault zoning diagnosis and alarm system based on fault recording according to claim 14, characterized in that: For polar region faults, the DC line faults are distinguished from other polar region faults based on the presence of restart signals in the fault recording data, including: UHV and EHV DC transmission systems have a restart logic after a DC line fault occurs. The restart logic will decide whether to perform a full-voltage restart, a reduced-voltage restart, or no restart based on the pre-fault operation mode, fault type, and fault duration of the DC transmission system. During the execution of the restart logic, the fault recording device records the corresponding signal changes. By analyzing the corresponding signals in the fault recording data during the execution of the restart logic, the DC line fault and other faults in the polar area are distinguished. The specific judgment method is as follows: If the fault recording data shows that the DC fault restart logic switch bit signal changes from 0 to 1, it is judged that a DC line fault has occurred; otherwise, it is judged that other faults in the DC polar area have occurred.

17. The DC fault zoning diagnosis and alarm system based on fault recording according to claim 14, characterized in that: For valve area faults, the faults of the converter transformers are distinguished from other faults in the valve area according to the protection action of the converter transformers in the fault recording data, including: For valve area faults, if the fault recording data shows that the converter transformer protection action switch position signal changes from 0 to 1, and before the change occurs, no other type of protection action switch position signal changes from 0 to 1, then it is judged that a converter transformer fault has occurred; otherwise, it is judged to be other valve area faults.

18. The DC fault zoning diagnosis and alarm system based on fault recording according to claim 10, characterized in that: The fault scenario judgment module is used to distinguish between maintenance and debugging and real fault scenarios by analyzing the DC power, DC voltage and DC current in the fault recording data before and after the fault, including: During the maintenance and commissioning of the DC transmission system, once the DC protection related tests are carried out, the recording will be triggered. By analyzing the changes in DC power, DC voltage and DC current recorded by the fault recorder before and after the fault occurs, it is judged whether the current situation is a planned maintenance and commissioning or an unexpected real fault. The specific judgment process is as follows: Set the pre-fault state to about 100ms before the fault recording trigger signal changes from 0 to 1; In the first period, the DC transmission system transmission power is greater than or equal to 0.1 pu; During the second period, the DC voltage is higher than the minimum DC voltage of the DC transmission system; If both the first time period and the second time period are satisfied, it is determined that a real DC power transmission system fault has occurred; otherwise, it is determined that the DC power transmission system is in a maintenance and debugging state.

19. An electronic device, characterized in that: The electronic device comprises: Processor and memory; The processor is used to execute the steps of the DC fault zoning diagnosis and alarm method based on fault recording as described in any one of claims 1 to 9 by calling the program or instruction stored in the memory.

20. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a program or instruction, and the program or instruction is a step for a computer to execute the DC fault partition diagnosis and alarm method as described in any one of claims 1 to 9.

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