Method, device, controller, storage medium and computer program product for monitoring a short circuit fault between poles of a direct current transmission line

Abstract

The application relates to a method and device for monitoring an inter-pole short-circuit fault of a direct-current transmission line, a controller, a storage medium and a computer program product. The method comprises obtaining a local direct-current line current and a remote direct-current line current of a rectifier station, and a remote direct-current line current and a local direct-current line current of an inverter station; if an absolute value of a difference between the local direct-current line current of the rectifier station and the local direct-current line current of the inverter station is greater than a first preset threshold value within a preset time, and an absolute value of a difference between the local direct-current line current of the rectifier station and the remote direct-current line current of the rectifier station is less than a second preset threshold value, it is determined that the direct-current transmission line has an inter-pole short-circuit fault; the first preset threshold value and the second preset threshold value are different. The method can accurately identify the inter-pole short-circuit fault in the direct-current transmission line.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of direct current transmission, in particular to a method and device for monitoring inter-pole short circuit fault of direct current transmission line, a controller, a storage medium and a computer program product. BACKGROUND

[0002] As a high-efficiency and high-power long-distance power transmission technology, direct current transmission is widely used in high-voltage power transmission. As an important part of direct current transmission, the direct current transmission line has a relatively high failure rate due to its long length and harsh working environment.

[0003] When a fault occurs in the direct current line, traveling wave protection and low voltage protection are used as the main protection means, and the longitudinal differential protection of the direct current line is used as the backup protection. When a high-resistance ground fault occurs, the traveling wave protection and the low voltage protection may not act, at which time the longitudinal differential protection needs to be used to identify and remove the fault.

[0004] However, the conventional longitudinal differential protection of the direct current line is usually designed for single-pole direct current line-to-ground short circuit fault, and each pole is configured separately. In the case of a serious inter-pole short circuit fault, the conventional longitudinal differential protection of the direct current line cannot effectively identify such a fault, which poses a challenge to the safe and stable operation of the direct current transmission system. SUMMARY

[0005] Therefore, it is necessary to provide a method and device for monitoring inter-pole short circuit fault of direct current transmission line, a controller, a storage medium and a computer program product, which can accurately identify the inter-pole short circuit fault in the direct current transmission line.

[0006] In a first aspect, the present application provides a method for monitoring inter-pole short circuit fault of direct current transmission line, the direct current transmission line being a connection line between a rectifier station and an inverter station of a direct current transmission project, and the method comprising:

[0007] obtaining the direct current line current of the self-pole of the rectifier station and the direct current line current of the opposite pole, and the direct current line current of the self-pole of the inverter station and the direct current line current of the opposite pole;

[0008] if the absolute value of the difference between the direct current line current of the self-pole of the rectifier station and the direct current line current of the self-pole of the inverter station is greater than a first preset threshold value within a preset time, and the absolute value of the difference between the direct current line current of the self-pole of the rectifier station and the direct current line current of the opposite pole of the rectifier station is less than a second preset threshold value, it is determined that the direct current transmission line has an inter-pole short circuit fault; the first preset threshold value and the second preset threshold value are different.

[0009] In one of the embodiments, the method further comprises:

[0010] In the case of determining that the DC transmission line has the inter-pole short-circuit fault, the bipolar of the rectifier station is simultaneously controlled to restart the DC line fault.

[0011] In one of the embodiments, the method further comprises:

[0012] In the case of determining that the DC transmission line has the inter-pole short-circuit fault, an alarm signal is output.

[0013] In one of the embodiments, the method further comprises:

[0014] If the absolute value of the difference between the DC line current of the pole of the rectifier station and the DC line current of the pole of the inverter station is greater than a first preset threshold value and the absolute value of the difference between the DC line current of the pole of the rectifier station and the DC line current of the opposite pole of the rectifier station is greater than a second preset threshold value within a preset time, it is determined that the DC transmission line has the single-pole-to-ground short-circuit fault of the DC line.

[0015] In one of the embodiments, the method further comprises:

[0016] If the absolute value of the difference between the DC line current of the opposite pole of the rectifier station and the DC line current of the opposite pole of the inverter station is greater than a first preset threshold value and the absolute value of the difference between the DC line current of the opposite pole of the rectifier station and the DC line current of the pole of the rectifier station is greater than a second preset threshold value within a preset time, it is determined that the DC transmission line has the single-pole-to-ground short-circuit fault of the DC line.

[0017] In one of the embodiments, the method further comprises:

[0018] In the case of determining that the DC transmission line has the single-pole-to-ground short-circuit fault, the rectifier station is controlled to restart the DC line fault of the pole having the single-pole-to-ground short-circuit fault of the DC line.

[0019] In a second aspect, the application further provides an inter-pole short-circuit fault monitoring device of a DC transmission line, the device comprising:

[0020] A current acquisition module is configured to acquire the DC line current of the pole of the rectifier station and the DC line current of the opposite pole of the rectifier station, and the DC line current of the pole of the inverter station and the DC line current of the opposite pole of the inverter station.

[0021] An inter-pole short-circuit fault determination module is configured to determine that the DC transmission line has the inter-pole short-circuit fault in the case that the absolute value of the difference between the DC line current of the pole of the rectifier station and the DC line current of the pole of the inverter station is greater than a first preset threshold value and the absolute value of the difference between the DC line current of the pole of the rectifier station and the DC line current of the opposite pole of the rectifier station is less than a second preset threshold value within a preset time; the first preset threshold value is different from the second preset threshold value.

[0022] In a third aspect, the present application also provides a controller comprising a memory and a processor, the memory storing a computer program, and the processor implementing the steps of the method of any of the above embodiments when executing the computer program.

[0023] In a fourth aspect, the present application also provides a computer-readable storage medium having a computer program stored thereon, the computer program being executed by a processor to implement the steps of the method of any of the above embodiments.

[0024] In a fifth aspect, the present application also provides a computer program product comprising a computer program, the computer program being executed by a processor to implement the steps of the method of any of the above embodiments.

[0025] The above method, device, controller, storage medium and computer program product for monitoring a DC transmission line for a pole-to-pole short circuit fault have at least the following beneficial effects:

[0026] In combination with the current change when a pole-to-pole short circuit fault occurs in the DC transmission line, the current of the DC line between the two stations of the same pole and the current of the DC line between the two poles of the same station are monitored to determine whether there is a large difference in the current of the DC line between the two stations of the same pole and whether the difference in the current of the DC line between the two poles of the same station is very small within a period of time. If so, it is determined that a pole-to-pole short circuit fault occurs in the DC transmission line. In this way, the pole-to-pole short circuit fault occurring in the DC transmission line operated in bipolar mode is effectively identified, thereby improving the safety and stability of the DC transmission system. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the drawings needed to be used in the description of the embodiments of the present application or the related art will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other related drawings can be obtained by those skilled in the art without any creative effort.

[0028] Figure 1 An application environment diagram of the method for monitoring a pole-to-pole short circuit fault of a DC transmission line in an embodiment;

[0029] Figure 2 A current flow direction diagram when a single-pole line is short-circuited to ground in a DC transmission line in an embodiment;

[0030] Figure 3 A waveform diagram of the current of the DC line of the same pole and the current of the DC line of the opposite pole of the rectifier station and the current of the DC line of the same pole and the current of the DC line of the opposite pole of the inverter station when a single-pole line is short-circuited to ground in a DC transmission line in an embodiment;

[0031] Figure 4 A schematic diagram of current flow when a DC transmission line has an inter-pole short circuit fault in an embodiment;

[0032] Figure 5 A schematic diagram of the flow of an inter-pole short circuit fault monitoring method for a DC transmission line in an embodiment;

[0033] Figure 6 A schematic diagram of the waveforms of the self-pole DC line current and the opposite-pole DC line current of a rectifier station and the self-pole DC line current of an inverter station when a DC transmission line has an inter-pole short circuit fault in an embodiment;

[0034] Figure 7 A block diagram of the structure of an inter-pole short circuit fault monitoring device for a DC transmission line in an embodiment;

[0035] Figure 8 A schematic diagram of the internal structure of a controller in an embodiment. DETAILED DESCRIPTION

[0036] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application.

[0037] The inter-pole short circuit fault monitoring method for a DC transmission line provided by the embodiments of the present application can be applied to a DC transmission line as shown in Figure 1 . The DC transmission line is a connection line between a DC engineering rectifier station and an inverter station. The self-pole DC line current and the opposite-pole DC line current of the rectifier station and the self-pole DC line current and the opposite-pole DC line current of the inverter station are obtained. If the absolute value of the difference between the self-pole DC line current of the rectifier station and the self-pole DC line current of the inverter station is greater than a first preset threshold value and the absolute value of the difference between the self-pole DC line current of the rectifier station and the opposite-pole DC line current of the rectifier station is less than a second preset threshold value within a preset time, it is determined that the DC transmission line has an inter-pole short circuit fault. The first preset threshold value is not equal to the second preset threshold value. The rectifier station is connected to the inverter station through a bipolar DC line for DC transmission, and the bipolar DC line includes a pole 1 DC line and a pole 2 DC line as shown in Figure 1 . The self-pole DC line current of the rectifier station refers to the current IdL flowing from the rectifier station to the pole 1 DC line, the opposite-pole DC line current of the rectifier station refers to the current IdL_op flowing from the pole 2 DC line to the rectifier station, the self-pole DC line current of the inverter station refers to the current IdL_os flowing from the pole 1 DC line to the inverter station, and the opposite-pole DC line current of the inverter station refers to the current IdL_op_os flowing from the inverter station to the pole 2 DC line.

[0038] For the DC transmission line, the DC transmission line is generally erected with the tower, and when wind deviation or suspension floating object occurs, the DC transmission line inter-pole short circuit fault is prone to occur. Although the conventional longitudinal differential protection method of the DC transmission line has a better effect on the recognition and protection of the single-pole-to-ground short circuit fault in the DC transmission line, it cannot accurately identify whether the inter-pole short circuit fault occurs in the DC transmission line in the bipolar line operation. Specifically, as shown in Figure 2 , when the single-pole-to-ground short circuit fault occurs in the DC transmission line in the bipolar operation, the short circuit current IdF formed by the ground short circuit fault point of the DC transmission line flows back to the DC system through the grounding electrode of the rectifier station and the inversion station. Because the short circuit current IdF flows out of the ground short circuit fault point of the DC line, there is a large difference between the DC line current of the own pole of the rectifier station and the DC line current IdL_os of the own pole of the inversion station; and because the short circuit current IdF formed by the ground short circuit fault point flows back to the DC system through the grounding electrode of the rectifier station, there is also a large difference between the DC line current of the own pole of the rectifier station and the DC line current of the opposite pole of the rectifier station, as shown in Figure 3 . As can be seen from Figure 3 , when the single-pole-to-ground short circuit fault occurs in the DC transmission line in the bipolar operation, it will cause the DC line current of the own pole of the rectifier station and the DC line current of the own pole of the inversion station to be unequal, but it does not affect the DC line current of the opposite pole of the rectifier station and the DC line current of the opposite pole of the inversion station, i.e. the DC line current of the opposite pole of the rectifier station and the DC line current of the opposite pole of the inversion station continue to remain equal. The conventional longitudinal differential protection method of the DC transmission line will delay for a period of time and then determine that the single-pole-to-ground short circuit fault exists in the DC transmission line if the absolute value ABS of the difference between the DC line current of the own pole of the rectifier station and the DC line current of the own pole of the inversion station exceeds the preset threshold value, such as ABS = IdL-IdL_os>1, and trigger the DC line fault restart instruction of each pole.

[0039] However, when the inter-pole short circuit fault occurs in the DC transmission line, as shown in Figure 4 , the DC line current of the own pole of the rectifier station will form a short circuit current IdF at the inter-pole DC line fault point, and flow back to the DC line of the opposite pole of the rectifier station through the DC line of the pole 2, which may also cause the absolute value ABS of the difference between the DC line current of the own pole of the rectifier station and the DC line current of the own pole of the inversion station to exceed the preset threshold value. If the conventional longitudinal differential protection method of the DC transmission line is still used for fault recognition and protection, it is obviously unable to accurately identify whether the reason for the above phenomenon is the single-pole-to-ground short circuit fault or the inter-pole short circuit fault, and perform the corresponding protection action.

[0040] Based on the above reasons, in an exemplary embodiment, as shown in Figure 5As shown, the present application provides a method for monitoring inter-pole short circuit fault of a DC transmission line, the DC transmission line is a connection line between a rectifier station and an inverter station of a DC transmission project, and the method comprises:

[0041] S502, obtaining the self-pole DC line current and the opposite-pole DC line current of the rectifier station, and the self-pole DC line current and the opposite-pole DC line current of the inverter station.

[0042] Wherein, the specific meanings of the self-pole DC line current of the rectifier station, the opposite-pole DC line current of the rectifier station, the self-pole DC line current of the inverter station and the opposite-pole DC line current of the inverter station are as described above, and will not be repeated here.

[0043] Exemplarily, in the process of DC transmission of the DC transmission line, the self-pole DC line current and the opposite-pole DC line current of the rectifier station, and the opposite-pole DC line current and the self-pole DC line current of the inverter station can be obtained through devices such as current transformers erected on the pole 1 DC line and the pole 2 DC line, so as to monitor whether there is a fault (such as an inter-pole short circuit fault) in the DC transmission line and determine the fault type.

[0044] S504, if the absolute value of the difference between the self-pole DC line current of the rectifier station and the self-pole DC line current of the inverter station is greater than a first preset threshold value and the absolute value of the difference between the self-pole DC line current of the rectifier station and the opposite-pole DC line current of the rectifier station is less than a second preset threshold value within a preset time, it is determined that the DC transmission line has an inter-pole short circuit fault; the first preset threshold value and the second preset threshold value are different.

[0045] Exemplarily, in the DC transmission line, the rectifier station is equivalent to the power supply side, and the inverter station is equivalent to the load side. When an inter-pole short circuit fault occurs in the DC transmission line operated by the bipolar line, for example, Figure 4 As shown, the self-pole DC line current of the rectifier station no longer flows back to the opposite-pole DC line of the rectifier station through the pole 1 DC line, the self-pole DC line of the inverter station, the opposite-pole DC line of the inverter station and the pole 2 DC line in turn, but directly flows back to the opposite-pole DC line of the rectifier station through the inter-pole DC line fault point and the pole 2 DC line. Since the self-pole DC line current of the rectifier station flows back to the pole 2 DC line through the inter-pole DC line fault point for the most part, a large difference appears between the self-pole DC line current of the rectifier station and the self-pole DC line current of the inverter station; a large difference also appears between the opposite-pole DC line current of the inverter station and the opposite-pole DC line current of the rectifier station; and because only the inter-pole short circuit occurs in the pole 1 DC line and the pole 2 DC line, no fault point-to-ground fault current path is formed, the waveform of the self-pole DC line current of the rectifier station and the opposite-pole DC line current of the rectifier station is basically consistent, and the difference is small, as shown in Figure 6

[0046] ​Based on the above phenomenon, the first preset threshold can be set as "threshold 1" to represent the difference between the direct current of the same pole of the rectifier station and the direct current of the same pole of the inverter station, and the second preset threshold can be set as "threshold 2" to represent the difference between the direct current of the same pole of the rectifier station and the direct current of the opposite pole of the rectifier station. It should be noted that the setting of the first preset threshold and the second preset threshold can be set according to the actual detection accuracy requirement, which is only exemplified here and is not limited. If the absolute value of the difference between the direct current of the same pole of the rectifier station and the direct current of the same pole of the inverter station is greater than the threshold 1 (i.e. |IdL-IdL_os|>threshold 1) and the absolute value of the difference between the direct current of the same pole of the rectifier station and the direct current of the opposite pole of the rectifier station is less than the threshold 2 (i.e. |IdL-IdL_op|<threshold 2) for a period of time, it indicates that there is a large difference between the direct current of the same pole of the rectifier station and the direct current of the same pole of the inverter station, and the difference between the direct current of the same pole of the rectifier station and the direct current of the opposite pole of the rectifier station is small, so it can be determined that there is a pole-to-pole short circuit fault in the direct current transmission line.

[0047] The pole-to-pole short circuit fault monitoring method of the direct current transmission line combines the current change when the pole-to-pole short circuit fault occurs in the direct current line, monitors the direct current of the same pole of the rectifier station and the direct current of the opposite pole of the rectifier station, and the direct current of the same pole of the inverter station and the direct current of the opposite pole of the inverter station, to determine whether there is a large difference in the current of the direct current line between the same poles of the two stations (between the rectifier station and the inverter station) and whether the difference in the current of the direct current line between the two poles of the same station is small for a period of time. If so, it can be determined that the direct current transmission line has a pole-to-pole short circuit fault, which effectively identifies the pole-to-pole short circuit fault in the bipolar direct current transmission line, thereby improving the safety and stability of the direct current transmission system.

[0048] In an exemplary embodiment, the method further comprises:

[0049] In the case where it is determined that there is a pole-to-pole short circuit fault in the direct current transmission line, the bipolar of the rectifier station is simultaneously controlled to restart the direct current line fault.

[0050] In the embodiment, in the case where it is determined that there is a pole-to-pole short circuit fault in the direct current transmission line, the bipolar of the rectifier station is controlled to synchronously perform the longitudinal differential protection action, so as to quickly isolate the fault area and prevent the fault from further spreading, thereby improving the safety and stability of the direct current transmission system, ensuring that measures can be taken in time when a serious pole-to-pole short circuit fault occurs, avoiding system collapse, and thus ensuring the normal operation of the direct current transmission system.

[0051] In an exemplary embodiment, the method further comprises:

[0052] When an inter-pole short-circuit fault is confirmed in a DC transmission line, an alarm signal is output.

[0053] In this embodiment, when an inter-pole short-circuit fault is determined to exist in the DC transmission line, an alarm signal is output so as to quickly notify the operators to take corresponding measures. This improves the safety and stability of the DC transmission system and ensures that measures can be taken in a timely manner when a serious fault such as an inter-pole short circuit occurs, so as to avoid system collapse and thus ensure the normal operation of the DC transmission system.

[0054] In one exemplary embodiment, the method further includes:

[0055] If, within a preset time, the absolute value of the difference between the DC line current of the rectifier station and the DC line current of the inverter station is greater than a first preset threshold, and the absolute value of the difference between the DC line current of the rectifier station and the DC line current of the opposite pole of the rectifier station is greater than a second preset threshold, then it is determined that there is a single-pole ground fault in the DC transmission line.

[0056] Alternatively, in an exemplary embodiment, the method further includes: if, within a preset time period, the absolute value of the difference between the DC line current of the rectifier station and the DC line current of the inverter station is greater than a first preset threshold, and the absolute value of the difference between the DC line current of the rectifier station and the DC line current of the rectifier station is greater than a second preset threshold, then it is determined that there is a DC line single-pole ground short-circuit fault in the DC transmission line.

[0057] For example, such as Figure 2 As shown, when a single-pole short-circuit fault occurs in a bipolar DC transmission line, taking pole 1 DC line as an example, a short-circuit current IdF is formed between pole 1 DC line and ground. This short-circuit current IdF flows back to the rectifier station via current IdF1 through the grounding electrode of the rectifier station, and back to the inverter station via current IdF2 through the grounding electrode of the inverter station. This results in the rectifier station's pole DC line current being unequal to the inverter station's pole DC line current (i.e., IdL ≠ IdL_os), but the rectifier station's opposite pole DC line current remains equal to the inverter station's opposite pole DC line current (i.e., IdL_op = IdL_op_os). Figure 3 As shown. Among them, Figure 3 The rectifier station's DC line current IdL (A) is the current IdL output from the rectifier station to the DC line of pole 1. The inverter station's DC line current IdL_os (A) is the current IdL_os input from the DC line of pole 1 to the inverter station. The rectifier station's DC line current IdL_op is the current IdL_op input from the DC line of pole 2 to the rectifier station. The inverter station's DC line current IdL_op_os is the current IdL_op_os output from the inverter station to the DC line of pole 2.Figure 3 It can be known that due to the part of current flowing out from the fault point of the inter-pole DC line, the pole DC line current of the rectifier station and the pole DC line current of the inverter station have a large difference. When the absolute value of the difference between the pole DC line current of the rectifier station and the pole DC line current of the inverter station is greater than a first preset threshold value, i.e., |IdL-IdL_os|>threshold value 1, and the absolute value of the difference between the pole DC line current of the rectifier station and the opposite pole DC line current of the rectifier station is greater than a second preset threshold value, i.e., |IdL-IdL_op|>threshold value 2, or when the absolute value of the difference between the opposite pole DC line current of the rectifier station and the opposite pole DC line current of the inverter station is greater than the first preset threshold value, i.e., |IdL_op-IdL_op_os|>threshold value 1, and the absolute value of the difference between the opposite pole DC line current of the rectifier station and the pole DC line current of the rectifier station is greater than the second preset threshold value, i.e., |IdL_op-IdL|>threshold value 2, within a period of time, it is determined that the DC transmission line has a single-pole-to-ground short circuit fault.

[0058] In the embodiment, a specific and feasible implementation manner is provided for determining that the DC transmission line has a single-pole-to-ground short circuit fault, so that the inter-pole short circuit fault monitoring method of the DC transmission line of the application has the ability to identify a single-pole-to-ground short circuit fault in addition to the function of identifying an inter-pole short circuit fault, and the normal operation of the DC transmission system is further ensured.

[0059] In one exemplary embodiment, the method further comprises:

[0060] In the case of determining that the DC transmission line has a single-pole-to-ground short circuit fault, the rectifier station is controlled to restart the DC line fault of the pole having the single-pole-to-ground short circuit fault of the DC line.

[0061] In the embodiment, in the case of determining that the DC transmission line has a single-pole-to-ground short circuit fault, the rectifier station restarts the DC line fault of the pole having the single-pole-to-ground short circuit fault of the DC line, so that measures can be taken in time when the single-pole-to-ground short circuit fault occurs, system collapse is avoided, and the normal operation of the DC transmission system is ensured.

[0062] It should be understood that although the steps in the flowcharts involved in the embodiments described above are shown in sequence according to the arrows, the steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, the execution of the steps is not strictly limited in sequence, and the steps can be executed in other sequences. Moreover, at least some of the steps in the flowcharts involved in the embodiments described above can include multiple steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of the steps or stages is not necessarily sequential, but can be alternately executed with other steps or steps or stages in other steps.

[0063] Based on the same inventive concept, the embodiments of the present application also provide a DC transmission line inter-pole short-circuit fault monitoring device for implementing the DC transmission line inter-pole short-circuit fault monitoring method described above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, so the specific limitations in one or more DC transmission line inter-pole short-circuit fault monitoring device embodiments provided below can refer to the limitations of the DC transmission line inter-pole short-circuit fault monitoring method described above, and will not be repeated here.

[0064] In one exemplary embodiment, as shown in Figure 7 A DC transmission line inter-pole short-circuit fault monitoring device is provided, comprising: a current acquisition module 702 and an inter-pole short-circuit fault determination module 704, wherein:

[0065] The current acquisition module 702 is configured to acquire the local DC line current and the opposite DC line current of the rectifier station, and the local DC line current and the opposite DC line current of the inverter station.

[0066] The inter-pole short-circuit fault determination module 704 is configured to, within a preset time, determine that the DC transmission line has an inter-pole short-circuit fault when the absolute value of the difference between the local DC line current of the rectifier station and the local DC line current of the inverter station is greater than a first preset threshold value, and the absolute value of the difference between the local DC line current of the rectifier station and the opposite DC line current of the rectifier station is less than a second preset threshold value. The first preset threshold value is less than the second preset threshold value.

[0067] In one exemplary embodiment, the DC transmission line inter-pole short-circuit fault monitoring device described above further comprises:

[0068] The first short-circuit protection module is configured to, in the case where it is determined that the DC transmission line has an inter-pole short-circuit fault, simultaneously control the two poles of the rectifier station to restart the DC line fault.

[0069] In an exemplary embodiment, the pole-to-pole short circuit fault monitoring device of the DC power transmission line further comprises:

[0070] The alarm module is configured to output an alarm signal when it is determined that the DC power transmission line has a pole-to-pole short circuit fault.

[0071] In an exemplary embodiment, the pole-to-pole short circuit fault monitoring device of the DC power transmission line further comprises:

[0072] The DC line single-pole-to-ground short circuit fault first determination module is configured to determine that the DC power transmission line has a DC line single-pole-to-ground short circuit fault when the absolute value of the difference between the DC line current of the pole of the rectifier station and the DC line current of the pole of the inverter station is greater than a first preset threshold value and the absolute value of the difference between the DC line current of the pole of the rectifier station and the DC line current of the opposite pole of the rectifier station is greater than a second preset threshold value within a preset time.

[0073] In an exemplary embodiment, the pole-to-pole short circuit fault monitoring device of the DC power transmission line further comprises:

[0074] The DC line single-pole-to-ground short circuit fault second determination module is configured to determine that the DC power transmission line has a DC line single-pole-to-ground short circuit fault when the absolute value of the difference between the DC line current of the opposite pole of the rectifier station and the DC line current of the opposite pole of the inverter station is greater than a first preset threshold value and the absolute value of the difference between the DC line current of the opposite pole of the rectifier station and the DC line current of the pole of the rectifier station is greater than a second preset threshold value within a preset time.

[0075] In an exemplary embodiment, the pole-to-pole short circuit fault monitoring device of the DC power transmission line further comprises:

[0076] The second short circuit protection module is configured to control the rectifier station to restart the DC line fault of the pole having the DC line single-pole-to-ground short circuit fault when it is determined that the DC power transmission line has a single-pole-to-ground short circuit fault.

[0077] The various modules in the pole-to-pole short circuit fault monitoring device of the DC power transmission line can be implemented in whole or in part by software, hardware, and combinations thereof. The various modules can be embedded in or independent of the processor in the computer device in hardware form, or stored in the memory in the computer device in software form, so as to be called and executed by the processor to perform the operations corresponding to the various modules.

[0078] In an exemplary embodiment, a computer device is provided, which can be a controller, and the internal structure diagram thereof can be as shown in Figure 8The controller includes a processor, a memory, an input / output interface (I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the controller is configured to provide computing and control capabilities. The memory of the controller includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for running the operating system and the computer program in the non-volatile storage medium. The database of the controller is configured to store the direct current line current and the input current of the rectifier station, and the direct current line current and the input current of the inverter station. The input / output interface of the controller is configured to exchange information between the processor and external devices. The communication interface of the controller is configured to communicate with external terminals through network connection. The computer program is executed by the processor to implement a method for monitoring an inter-pole short-circuit fault of a direct current transmission line.

[0079] Those skilled in the art can understand that, Figure 8 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0080] In an exemplary embodiment, a computer device is provided, including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps in the above method embodiments.

[0081] In an embodiment, a computer readable storage medium is provided, storing a computer program, and the computer program is executed by a processor to implement the steps in the above method embodiments.

[0082] In an embodiment, a computer program product is provided, including a computer program, and the computer program is executed by a processor to implement the steps in the above method embodiments.

[0083] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when executed, can include the processes of the above-mentioned embodiment methods. Any reference to memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile memory and volatile memory. The non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical storage, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. The volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration but not limitation, the RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The database involved in the embodiments provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in the embodiments provided in the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, an artificial intelligence (AI) processor, etc., without being limited thereto.

[0084] The technical features of the above embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not exist contradictions, they should be considered as the scope of the present application.

[0085] The above-described embodiments are merely illustrative of several embodiments of the present application, and the description is relatively specific and detailed, but should not be understood as a limitation on the scope of the patent. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of the present application. Therefore, the scope of protection of the present application should be subject to the appended claims.

Claims

1. A method of monitoring for a pole-to-pole short circuit fault of a DC power transmission line, characterized by, The direct current transmission line is a connection line between a rectifier station and an inverter station of a direct current transmission project, and the method comprises the following steps: obtaining the direct current line current of the rectifier station and the direct current line current of the inverter station; if the absolute value of the difference between the direct current line current of the rectifier station and the direct current line current of the inverter station is greater than a first preset threshold value and the absolute value of the difference between the direct current line current of the rectifier station and the direct current line current of the opposite pole of the rectifier station is less than a second preset threshold value within a preset time, it is determined that the direct current transmission line has an inter-pole short circuit fault; the first preset threshold value is different from the second preset threshold value.

2. The method of monitoring for a short circuit fault between poles of a DC power transmission line according to claim 1, characterized in that, The method further comprises the following steps: controlling the two poles of the rectifier station to restart the direct current line fault in the case that it is determined that the direct current transmission line has an inter-pole short circuit fault.

3. The method of monitoring for a short circuit fault between poles of a DC power transmission line according to claim 1, wherein, The method further comprises the following steps: outputting an alarm signal in the case that it is determined that the direct current transmission line has an inter-pole short circuit fault.

4. The method of monitoring for a short circuit fault between poles of a DC power transmission line according to claim 1, wherein, The method further comprises the following steps: if the absolute value of the difference between the direct current line current of the rectifier station and the direct current line current of the inverter station is greater than the first preset threshold value and the absolute value of the difference between the direct current line current of the rectifier station and the direct current line current of the opposite pole of the rectifier station is greater than the second preset threshold value within the preset time, it is determined that the direct current transmission line has a single-pole-to-ground short circuit fault.

5. The method of monitoring for a short circuit fault between poles of a DC power transmission line according to claim 1, wherein, The method further comprises the following steps: if the absolute value of the difference between the direct current line current of the rectifier station and the direct current line current of the inverter station is greater than the first preset threshold value and the absolute value of the difference between the direct current line current of the rectifier station and the direct current line current of the opposite pole of the rectifier station is greater than the second preset threshold value within the preset time, it is determined that the direct current transmission line has a single-pole-to-ground short circuit fault.

6. The method of monitoring for a short circuit fault between poles of a DC power transmission line according to claim 4 or 5, characterized in that, The method further comprises the following steps: controlling the rectifier station to restart the direct current line fault of the pole having the single-pole-to-ground short circuit fault in the case that it is determined that the direct current transmission line has a single-pole-to-ground short circuit fault.

7. A device for monitoring a short circuit fault between poles of a direct current transmission line, characterized in that The device comprises: a current collection module for obtaining the direct current line current of the rectifier station and the direct current line current of the inverter station; an inter-pole short circuit fault determination module for determining that the direct current transmission line has an inter-pole short circuit fault if the absolute value of the difference between the direct current line current of the rectifier station and the direct current line current of the inverter station is greater than a first preset threshold value and the absolute value of the difference between the direct current line current of the rectifier station and the direct current line current of the opposite pole of the rectifier station is less than a second preset threshold value within a preset time; the first preset threshold value is less than the second preset threshold value.

8. A controller comprising a memory and a processor, the memory storing a computer program, characterized in that, The processor executes the computer program to realize the steps of the method in any one of claims 1 to 6.

9. A computer readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to realize the steps of the method in any one of claims 1 to 6.

10. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to realize the steps of the method in any one of claims 1 to 6.

Images