Grounding electrode bus protection method and device for common grounding electrode converter station, computer device, readable storage medium and program product

Abstract

The application relates to a ground electrode bus protection method and device of a common ground electrode converter station, computer equipment, a computer readable storage medium and a computer program product. The method comprises the following steps: calculating a first current difference value between the current flowing into each current measuring point on the ground electrode bus and the current flowing out; in the case that the duration of the first current difference value being greater than a first threshold value is greater than a first time length, controlling the bipolar balanced operation of the first converter station; recalculating a second current difference value between the current flowing into each current measuring point and the current flowing out, and calculating a third current difference value between the current flowing into the current measuring point on two branches in parallel in the ground electrode line of the first converter station; in the case that the duration of the second current difference value and the third current difference value being greater than the first threshold value is greater than a second time length, controlling the lockout of the converter of the first converter station and outputting prompt information. The method can improve the accuracy of the ground electrode bus protection.

Description

Technical Field

[0001] This application relates to the field of DC power transmission technology, and in particular to a method, apparatus, computer equipment, computer-readable storage medium, and computer program product for protecting the grounding busbar of a common grounding converter station. Background Technology

[0002] A converter station is a station in a DC transmission system used to convert alternating current (AC) to direct current (DC) or vice versa. The grounding electrode is connected to the converter station, allowing direct current to be injected into the ground through the two grounding electrodes.

[0003] With the increasingly widespread application of DC transmission systems, the demand for grounding electrodes is also increasing. Since grounding electrodes typically occupy a large area, current DC transmission systems mainly use a shared grounding electrode method. Different converter stations converge at the grounding electrode location via grounding electrode lines. The line connecting the bipolar junction of the converter stations to the grounding electrode is called the grounding electrode busbar.

[0004] However, since converter stations sharing a common grounding electrode are actually interconnected through the grounding electrode, the protection methods for the grounding electrode busbar in related technologies are less effective, resulting in poor accuracy in identifying grounding electrode line faults and potential safety hazards. Summary of the Invention

[0005] Therefore, it is necessary to provide a method, apparatus, computer equipment, computer-readable storage medium, and computer program product for protecting the grounding busbar of a shared grounding electrode converter station, which can improve the accuracy of protection, in response to the above-mentioned technical problems.

[0006] Firstly, this application provides a method for protecting the grounding busbar of a common grounding electrode converter station, including:

[0007] The current at each current measuring point on the grounding electrode bus is obtained, and the deviation between the current flowing into and out of each current measuring point is calculated to obtain the first current difference value; each current measuring point is located at least on two parallel branches on the DC neutral bus of the first pole, the DC neutral bus of the second pole, the in-station grounding point of the first converter station, and the grounding electrode line of the first converter station.

[0008] If the duration for which the first current difference is greater than a preset first threshold is greater than a preset first duration, the first converter station is controlled to operate in bipolar balanced mode.

[0009] The current at each current measuring point on the grounding electrode bus is obtained again, and the deviation between the current flowing into and out of each current measuring point is recalculated to obtain the second current difference. The deviation between the current flowing into and out of the current at the current measuring points on the two parallel branches of the grounding electrode line of the first converter station is calculated to obtain the third current difference.

[0010] If the duration for which both the second current difference and the third current difference are greater than the first threshold is greater than a preset second duration, the first converter station is controlled to lock the converter and output a prompt message; the prompt message is used to indicate the blocking of fault current from the second converter station.

[0011] In one embodiment, after acquiring the current at each current measuring point on the grounding electrode bus again and recalculating the deviation between the current flowing into and out of each current measuring point to obtain a second current difference, and calculating the deviation between the current flowing into and out of the current at the current measuring points on the two parallel branches of the grounding electrode line of the first converter station to obtain a third current difference, the process then includes:

[0012] The deviation between the current flowing into and out of the current measuring point on the DC neutral bus of the first pole and the current measuring point on the DC neutral bus of the second pole is calculated to obtain a fourth current difference value; the fourth current difference value is used to determine whether the fault current of the grounding pole bus comes from the first converter station.

[0013] In one embodiment, when the duration for which both the second current difference and the third current difference are greater than the first threshold is greater than a preset second duration, controlling the first converter station to lock the converter and output a prompt message includes:

[0014] When both the second current difference and the third current difference are greater than the first threshold, and the duration for which the fourth current difference is less than the preset second threshold is greater than the preset second duration, the first converter station is controlled to lock the converter and output a first prompt message; the first prompt message is used to indicate switching the operating mode of the second converter station.

[0015] In one embodiment, switching the operating mode of the second converter station includes:

[0016] When the second converter station is in bipolar operation mode, control the bipolar balanced operation of the second converter station;

[0017] When the second converter station is in monopolar operation mode, control the second converter station to switch to monopolar metal operation mode.

[0018] In one embodiment, when the duration for which both the second current difference and the third current difference are greater than the first threshold is greater than a preset second duration, controlling the first converter station to lock the converter and output a prompt message includes:

[0019] When both the second current difference and the third current difference are greater than the first threshold, and the duration for which the fourth current difference is greater than the preset second threshold is greater than the preset second duration, the first converter station is controlled to lock the converter and output a second prompt message; the second prompt message is used to indicate the blocking of fault current from the first converter station and the second converter station.

[0020] In one embodiment, after acquiring the current at each current measuring point on the grounding electrode bus again and recalculating the deviation between the current flowing into and out of each current measuring point to obtain a second current difference, and calculating the deviation between the current flowing into and out of the current at the current measuring points on the two parallel branches of the grounding electrode line of the first converter station to obtain a third current difference, the process then includes:

[0021] If the second current difference is greater than the first threshold and the third current difference is less than the first threshold, the converter of the first converter station is locked.

[0022] Secondly, this application also provides a grounding electrode busbar protection device for a shared grounding electrode converter station, comprising:

[0023] The first processing module is used to acquire the current at each current measuring point on the grounding electrode bus, and calculate the deviation between the current flowing into and out of each current measuring point to obtain a first current difference value; each current measuring point is located at least on two parallel branches on the DC neutral bus of the first pole, the DC neutral bus of the second pole, the in-station grounding point of the first converter station, and the grounding electrode line of the first converter station.

[0024] The first control module is used to control the bipolar balanced operation of the first converter station when the duration of the first current difference being greater than a preset first threshold is greater than a preset first duration.

[0025] The second processing module is used to acquire the current of each current measuring point on the grounding electrode busbar again, and recalculate the deviation between the current flowing into and out of each current measuring point to obtain the second current difference value. It also calculates the deviation between the current flowing into and out of the current on the two branches connected in parallel in the grounding electrode line of the first converter station to obtain the third current difference value.

[0026] The second control module is used to control the first converter station to lock the converter and output a prompt message when the duration for which both the second current difference and the third current difference are greater than the first threshold is greater than a preset second duration; the prompt message is used to indicate the blocking of fault current from the second converter station.

[0027] Thirdly, this application also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method described in any of the above claims.

[0028] Fourthly, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in any of the preceding claims.

[0029] Fifthly, this application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described in any of the above claims.

[0030] The aforementioned grounding busbar protection method, device, computer equipment, computer-readable storage medium, and computer program product for a shared grounding electrode converter station can determine whether a fault current exists in the grounding busbar by measuring the current flowing into and out of the grounding busbar of the first converter station; by controlling the bipolar balanced operation of the first converter station after a fault current exists in the grounding busbar and persists for a period of time, it can block the fault current from the first converter station; by measuring the current flowing into and out of the grounding electrode line, it can determine whether the fault current flows in from the grounding electrode line, thus identifying the situation where the fault current originates from the shared grounding electrode; by controlling the first converter station to lock the converter and prompting the operators to take measures to block the fault current from the second converter station after the fault current persists and flows in from the grounding electrode line for a period of time, it achieves effective differential protection of the grounding busbar and improves the reliability of the DC transmission system. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram showing the location of the current measuring point on the grounding electrode bus in related technologies;

[0033] Figure 2This is a schematic diagram showing the location of each current measuring point on the grounding electrode bus in an embodiment where a common grounding electrode exists.

[0034] Figure 3 This is a flowchart illustrating a grounding busbar protection method for a shared grounding electrode converter station in one embodiment.

[0035] Figure 4 This is a flowchart illustrating a grounding busbar protection method for a shared grounding converter station in another embodiment.

[0036] Figure 5 This is a flowchart illustrating the grounding busbar protection method for a shared grounding electrode converter station in yet another embodiment.

[0037] Figure 6 This is a structural block diagram of a grounding busbar protection device for a common grounding converter station in one embodiment;

[0038] Figure 7 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0040] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0041] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0042] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0043] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0044] Please refer to Figure 1 , Figure 1 This is a schematic diagram showing the locations of current measuring points on the grounding electrode busbar in related technologies. The diagram illustrates that the first converter station is connected to the target grounding electrode via the grounding electrode busbar, and the first converter station includes a first pole and a second pole. The grounding electrode busbar includes the DC neutral busbar of the first pole, the DC neutral busbar of the second pole, connecting lines, and the grounding electrode line. The first end of the DC neutral busbar of the first pole and the first end of the DC neutral busbar of the second pole are respectively connected to the first pole and the second pole of the first converter station. The second end of the DC neutral busbar of the first pole and the second end of the DC neutral busbar of the second pole are connected and then connected to the first end of the connecting line. The first ends of the two parallel branches in the grounding electrode line are connected and then connected to the second end of the connecting line. The second ends of the two parallel branches in the grounding electrode line are connected to the grounding electrode through resistors.

[0045] For the protection method of the grounding bus in related technologies, please refer to Table 1, where: IdE is the current of the current measuring point on the DC neutral bus of the first pole, IdE_OP is the current of the current measuring point on the DC neutral bus of the second pole, IdSG is the current of the current measuring point at the grounding point of the first converter station on the connecting line, and Idee1 and Idee2 are the currents of the current measuring points on the two parallel branches in the grounding electrode line.

[0046] Table 1

[0047]

[0048] In this situation, since the criterion value |IdE - IdE_OP -Idee1 - Idee2 - IdSG| is not 0 when there is a ground fault in the grounding bus, the protection method for the grounding bus in related technologies, when the criterion value is greater than the preset first threshold, controls the bipolar balanced operation of the first converter station after a delay of t1 so that IdE equals IdE_OP, and the fault grounding point achieves arc extinguishing; when the bipolar balanced operation cannot reduce the fault current and the fault current continues to exist, after a delay of t2, controls the first converter station to lock the converter so as to eliminate the fault by power failure.

[0049] Please refer to Figure 2 , Figure 2 This is a schematic diagram showing the locations of current measuring points on the grounding busbar in one embodiment where a shared grounding electrode exists. The target grounding electrode is also connected to the second converter station. When the second converter station is operating in monopolar polarity mode, if a ground fault occurs on the grounding busbar of the first converter station, the ground current I1 of the second converter station will flow to the ground via the target grounding electrode. Figure 2 I in 1-G ), flowing to the ground via the grounding electrode line of the first converter station and the fault grounding point ( Figure 2 I in 1-F This forms a parallel grounding loop. The protection methods for the grounding busbar in related technologies cannot interrupt the current I flowing from the second converter station to the fault grounding point. 1-F This causes current to continuously flow through the faulty grounding point, which can easily damage the equipment.

[0050] In one embodiment, such as Figure 3 As shown, a method for protecting the grounding busbar of a shared grounding electrode converter station is provided. This embodiment illustrates the method by applying it to a terminal. It is understood that this method can also be applied to a server, and to a system including both a terminal and a server, and implemented through interaction between the terminal and the server. In this embodiment, the method includes the following steps:

[0051] Step S102: Obtain the current at each current measuring point on the grounding electrode bus, and calculate the deviation between the current flowing into and out of each current measuring point to obtain the first current difference value; each current measuring point is located at least on two parallel branches on the DC neutral bus of the first pole, the DC neutral bus of the second pole, the grounding point in the first converter station, and the grounding electrode line of the first converter station.

[0052] For example, please continue to refer to Figure 2 The current at each current measuring point on the grounding electrode busbar includes at least the current IdE at the current measuring point on the DC neutral busbar of the first electrode, the current IdE_OP at the current measuring point on the DC neutral busbar of the second electrode, the current IdSG at the current measuring point at the grounding point within the first converter station, and the currents Idee1 and Idee2 at the current measuring points on the two parallel branches in the grounding electrode line. The grounding electrode busbar can be considered as a current node. According to Kirchhoff's current law, when there is no grounding fault in the grounding electrode busbar, the current flowing into and out of the grounding electrode busbar is balanced; when there is a grounding fault in the grounding electrode busbar, the deviation between the current flowing into and out of the grounding electrode busbar is equal to the fault current.

[0053] Step S104: If the duration for which the first current difference is greater than a preset first threshold is greater than a preset first duration, control the first converter station to operate in bipolar balance.

[0054] Specifically, the first current difference can be calculated using the first formula. The first formula includes:

[0055] ;

[0056] When the first current difference If the current difference exceeds a preset first threshold I_set, it indicates a grounding fault in the grounding busbar. Therefore, at the first current difference... If the duration of the first threshold I_set is greater than the preset first duration t1, the first converter station can be controlled to operate in bipolar balance so that IdE equals IdE_OP.

[0057] Step S106: Obtain the current at each current measuring point on the grounding electrode busbar again, and recalculate the deviation between the current flowing into and out of each current measuring point to obtain the second current difference. Calculate the deviation between the current flowing into and out of the current at the current measuring points on the two parallel branches of the grounding electrode line of the first converter station to obtain the third current difference.

[0058] Similarly, after controlling the bipolar balanced operation of the first converter station, the current at each current measuring point on the grounding bus can be acquired again, and the deviation between the current flowing into and out of each current measuring point can be recalculated to obtain the second current difference value. .

[0059] Step S108: If the duration for which both the second current difference and the third current difference are greater than the first threshold is greater than the preset second duration, control the first converter station to lock the converter and output a prompt message; the prompt message is used to indicate the blocking of fault current from the second converter station.

[0060] Specifically, the third current difference can be calculated using the second formula. The second formula includes:

[0061] ;

[0062] When the second current difference If the value is greater than the first threshold I_set, it indicates that a grounding fault still exists in the grounding bus; when the third current difference... If the current difference is greater than the first threshold I_set, it indicates that the fault current is flowing into the grounding electrode line. Therefore, in the second current difference... and the difference between the third current If the duration of all values ​​exceeding the first threshold I_set is greater than the preset second duration t2, the first converter station can be controlled to lock the converter and output a prompt message, so as to eliminate the fault by cutting off the power to the first converter station and blocking the fault current from the second converter station.

[0063] In the above-mentioned protection method for the grounding busbar of a shared grounding electrode converter station, the presence of fault current in the grounding busbar can be determined by the current flowing into and out of the grounding busbar of the first converter station; by controlling the bipolar balanced operation of the first converter station after a fault current has existed in the grounding busbar for a period of time, the fault current from the first converter station can be blocked; by the current flowing into and out of the grounding electrode line, it can be determined whether the fault current flows in from the grounding electrode line, thus identifying the situation where the fault current originates from the shared grounding electrode; by controlling the first converter station to lock the converter and prompting the operators to take measures to block the fault current from the second converter station after the fault current has existed continuously and flowed in from the grounding electrode line for a period of time, effective differential protection of the grounding busbar is achieved, improving the reliability of the DC transmission system.

[0064] In one exemplary embodiment, such as Figure 4 As shown, the above method may further include:

[0065] Step S107: Calculate the deviation between the current flowing into and out of the current measuring point on the DC neutral bus of the first pole and the current measuring point on the DC neutral bus of the second pole, and obtain the fourth current difference value; the fourth current difference value is used to determine whether the fault current of the grounding electrode bus comes from the first converter station.

[0066] Specifically, the fourth current difference can be calculated using the third formula. The third formula includes:

[0067] ;

[0068] When the fourth current difference Reaching the preset second threshold Iset1 indicates that the fault current originates from the first converter station. The setting of the second threshold Iset1 mainly considers the control deviation and measurement deviation of controlling the bipolar balanced operation of the first converter station, while retaining a certain margin.

[0069] In this embodiment, the current flowing into and out of the bipolar DC neutral bus of the first converter station can be used to identify situations where the bipolar balanced operation of the first converter station cannot reduce the fault current.

[0070] For further information, please continue to refer to [link / reference]. Figure 4 The above step S108 may include:

[0071] Step S1081: When both the second current difference and the third current difference are greater than the first threshold, and the duration for which the fourth current difference is less than the preset second threshold is greater than the preset second duration, control the first converter station to lock the converter and output the first prompt information; the first prompt information is used to indicate the switching of the second converter station's operating mode.

[0072] Specifically, when the second current difference If the value is greater than the first threshold I_set, it indicates that a grounding fault still exists in the grounding bus; when the third current difference... If the current difference is greater than the first threshold I_set, it indicates that the fault current flows in from the grounding electrode line. At this time, the second converter station may be in bipolar or unipolar operation, etc. When the fourth current difference... If the value is less than the preset second threshold Iset1, it indicates that the bipolar balanced operation of the first converter station can reduce the fault current, and the fault current does not flow in from the converter valve of the first converter station. Therefore, the first converter station can be controlled to lock the converter and output a first prompt message to avoid damage to the equipment of the first converter station, and the fault current from the second converter station can be blocked by switching the operation mode of the second converter station.

[0073] In one possible implementation, the above-mentioned switching of the second converter station's operating mode includes:

[0074] Step A1: When the second converter station is in bipolar operation mode, control the bipolar balanced operation of the second converter station.

[0075] Among them, bipolar operation mode is a bipolar DC transmission operation mode in which the ground serves as the current return path between the neutral points of the high-voltage DC system. In bipolar operation mode, the DC current flows through the grounding electrode. During bipolar balanced operation, the voltage and current magnitudes of the two electrodes are equal, and there is basically no current flowing through the grounding electrode.

[0076] Step A2: When the second converter station is in monopolar operation mode, control the second converter station to switch to monopolar metal operation mode.

[0077] Among them, the monopolar polarity operation mode is a monopolar DC transmission operation mode in which the ground serves as the current return path between the neutral points of the HVDC converter station, and the DC current flows through the grounding electrode in the monopolar polarity operation mode. The monopolar metallic operation mode uses a metallic conductor as the current return path between the neutral points of the HVDC system, and basically no current flows through the grounding electrode in the monopolar metallic operation mode.

[0078] Alternatively, please continue to refer to Figure 4 The above step S108 may include:

[0079] In step S1082, if both the second current difference and the third current difference are greater than the first threshold, and the duration for which the fourth current difference is greater than the preset second threshold is greater than the preset second duration, the first converter station is controlled to lock the converter and output a second prompt message; the second prompt message is used to indicate the blocking of fault current from the first converter station and the second converter station.

[0080] Specifically, when the second current difference If the value is greater than the first threshold I_set, it indicates that a grounding fault still exists in the grounding bus; when the third current difference... Greater than the first threshold I_set, and the fourth current difference Reaching the preset second threshold Iset1 indicates that the bipolar balanced operation of the first converter station cannot reduce the fault current, and the source of the fault current cannot be determined. Therefore, the first converter station can be controlled to lock out the converter and output a second prompt message to avoid damage to the equipment of the first converter station and to further verify the source of the fault current, blocking the fault current from both the first and second converter stations. For example, the second prompt message can be used to remind operators to pay attention to the existence of a grounding point within the station and to verify the operating mode of the second converter station.

[0081] In one exemplary embodiment, such as Figure 5 As shown, the above method may further include:

[0082] Step S109: When the second current difference is greater than the first threshold and the third current difference is less than the first threshold, control the first converter station to lock the converter.

[0083] Specifically, when the second current difference If the value is greater than the first threshold I_set, it indicates that a grounding fault still exists in the grounding bus; when the third current difference... If the current is less than the first threshold I_set, it indicates that the fault current is not flowing in from the grounding electrode line. Therefore, the converter in the first converter station can be shut down to eliminate the fault by de-energizing the first converter station.

[0084] In an exemplary embodiment, the grounding bus protection method for a shared grounding electrode converter station is described in Table 2, where: |IdE - IdE_OP - Idee1 - Idee2 - IdSG| > I_set is used to characterize the presence of fault current on the grounding bus; |IdE - IdE_OP| < Iset1 is used to characterize that the bipolar balanced operation of the first converter station can reduce the fault current, and the fault current does not flow in from the converter valve of the first converter station; |Idee1 + Idee2| > I_set is used to characterize that the fault current flows in from the grounding electrode line; |Idee1 + Idee2| < I_set is used to characterize that the fault current does not flow in from the grounding electrode line; |IdE - IdE_OP| ≥ Iset1 & |Idee1 + Idee2| > I_set is used to characterize that the bipolar balanced operation of the first converter station cannot reduce the fault current, and the source of the fault current cannot be determined. The first notification message can be used to inform operators to switch the operating mode of the second converter station; the second notification message can be used to remind operators to pay attention to the existence of grounding points within the station and to verify the operating mode of the second converter station.

[0085] Table 2

[0086]

[0087] In this scenario, after acquiring the current at each current measuring point on the grounding busbar, if the current at each current measuring point satisfies criterion C0, after a delay of t1, the first converter station is controlled to operate in bipolar balanced mode. The current at each current measuring point on the grounding busbar is acquired again. If the current at each current measuring point satisfies criterion C11, after a delay of t2, the first converter station is controlled to lock the converter and output a first prompt message. If the current at each current measuring point satisfies criterion C12, after a delay of t2, the first converter station is controlled to lock the converter and output a second prompt message. It is understood that criteria C11, C12, and C13 are mutually exclusive.

[0088] In summary, the above-mentioned protection method for the grounding busbar of a shared grounding electrode converter station can determine whether a fault current exists in the grounding busbar by observing the current flowing into and out of the grounding busbar of the first converter station; by controlling the bipolar balanced operation of the first converter station after a fault current exists in the grounding busbar for a period of time, the fault current from the first converter station can be blocked; by observing the current flowing into and out of the grounding electrode line, it can be determined whether the fault current flows in from the grounding electrode line, thus identifying the situation where the fault current originates from the shared grounding electrode; by controlling the first converter station to lock the converter and prompting the operators to take measures to block the fault current from the second converter station after the fault current persists and flows in from the grounding electrode line for a period of time, effective differential protection of the grounding busbar is achieved, improving the reliability of the DC transmission system.

[0089] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0090] Based on the same inventive concept, this application also provides a grounding bus protection device for a shared grounding electrode converter station, used to implement the above-described method for protecting the grounding bus of a shared grounding electrode converter station. The solution provided by this device is similar to the solution described in the above method. Therefore, the specific limitations of one or more embodiments of the grounding bus protection device for a shared grounding electrode converter station provided below can be found in the limitations of the grounding bus protection method for a shared grounding electrode converter station described above, and will not be repeated here.

[0091] In one exemplary embodiment, such as Figure 6 As shown, a grounding busbar protection device 200 for a shared grounding electrode converter station is provided, comprising: a first processing module 201, a first control module 202, a second processing module 203, and a second control module 204, wherein:

[0092] The first processing module 201 is used to acquire the current at each current measuring point on the grounding electrode bus, and calculate the deviation between the current flowing into and out of each current measuring point to obtain the first current difference value; each current measuring point is located at least on two parallel branches on the DC neutral bus of the first pole, the DC neutral bus of the second pole, the in-station grounding point of the first converter station, and the grounding electrode line of the first converter station.

[0093] The first control module 202 is used to control the bipolar balanced operation of the first converter station when the duration of the first current difference being greater than a preset first threshold is greater than a preset first duration.

[0094] The second processing module 203 is used to acquire the current at each current measuring point on the grounding electrode busbar again, and recalculate the deviation between the current flowing into and out of each current measuring point to obtain the second current difference value. It also calculates the deviation between the current flowing into and out of the current at the current measuring points on the two parallel branches of the grounding electrode line of the first converter station to obtain the third current difference value.

[0095] The second control module 204 is used to control the first converter station to lock the converter and output a prompt message when the duration for which both the second current difference and the third current difference are greater than the first threshold is greater than a preset second duration; the prompt message is used to indicate the blocking of fault current from the second converter station.

[0096] In an exemplary embodiment, the grounding busbar protection device 200 of the aforementioned shared grounding electrode converter station includes:

[0097] The third processing module is used to calculate the deviation between the current flowing into and out of the current measuring point on the DC neutral bus of the first pole and the current measuring point on the DC neutral bus of the second pole, and obtain the fourth current difference value; the fourth current difference value is used to determine whether the fault current of the grounding electrode bus comes from the first converter station.

[0098] In one exemplary embodiment, the second control module 204 includes:

[0099] The first control submodule is used to control the first converter station to lock the converter and output a first prompt message when the second current difference and the third current difference are both greater than the first threshold, and the duration for which the fourth current difference is less than the preset second threshold is greater than the preset second duration; the first prompt message is used to indicate the switching of the second converter station's operating mode.

[0100] In an exemplary embodiment, the above-mentioned switching of the second converter station's operating mode includes:

[0101] When the second converter station is in bipolar operation mode, control the bipolar balanced operation of the second converter station;

[0102] When the second converter station is in monopolar operation mode, control the second converter station to switch to monopolar metal operation mode.

[0103] In one exemplary embodiment, the second control module 204 includes:

[0104] The second control submodule is used to control the first converter station to lock the converter and output a second prompt message when the second current difference and the third current difference are both greater than the first threshold, and the duration for which the fourth current difference is greater than the preset second threshold is greater than the preset second duration; the second prompt message is used to indicate the blocking of fault current from the first converter station and the second converter station.

[0105] In an exemplary embodiment, the grounding busbar protection device 200 of the aforementioned shared grounding electrode converter station includes:

[0106] The third control module is used to control the first converter station to lock the converter when the second current difference is greater than the first threshold and the third current difference is less than the first threshold.

[0107] Each module in the grounding busbar protection device of the aforementioned shared grounding electrode converter station can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0108] In one exemplary embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 7 As shown, the computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores current data. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements a grounding bus protection method for a shared grounding converter station.

[0109] Those skilled in the art will understand that Figure 7The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0110] In one exemplary embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0111] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps in the above method embodiments.

[0112] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0113] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0114] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0115] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for protecting the grounding busbar of a converter station sharing a grounding electrode, wherein a first converter station is connected to a target grounding electrode via a grounding busbar, and the target grounding electrode is also connected to a second converter station, the first converter station comprising a first electrode and a second electrode, characterized in that, The method includes: The current at each current measuring point on the grounding electrode bus is obtained, and the deviation between the current flowing into and out of each current measuring point is calculated to obtain the first current difference value; each current measuring point is located at least on two parallel branches on the DC neutral bus of the first pole, the DC neutral bus of the second pole, the in-station grounding point of the first converter station, and the grounding electrode line of the first converter station. If the duration for which the first current difference is greater than a preset first threshold is greater than a preset first duration, the first converter station is controlled to operate in bipolar balanced mode. The current at each current measuring point on the grounding electrode bus is obtained again, and the deviation between the current flowing into and out of each current measuring point is recalculated to obtain the second current difference. The deviation between the current flowing into and out of the current at the current measuring points on the two parallel branches of the grounding electrode line of the first converter station is calculated to obtain the third current difference. If the duration for which both the second current difference and the third current difference are greater than the first threshold is greater than a preset second duration, the first converter station is controlled to lock the converter and output a prompt message; the prompt message is used to indicate the blocking of fault current from the second converter station.

2. The method according to claim 1, characterized in that, The process involves: acquiring the current at each current measuring point on the grounding electrode busbar again, recalculating the deviation between the current flowing into and out of each current measuring point to obtain a second current difference, calculating the deviation between the current flowing into and out of the current at the current measuring points on the two parallel branches of the grounding electrode line of the first converter station to obtain a third current difference, and then including: The deviation between the current flowing into and out of the current measuring point on the DC neutral bus of the first pole and the current measuring point on the DC neutral bus of the second pole is calculated to obtain a fourth current difference value; the fourth current difference value is used to determine whether the fault current of the grounding pole bus comes from the first converter station.

3. The method according to claim 2, characterized in that, When the duration for which both the second current difference and the third current difference are greater than the first threshold is greater than a preset second duration, the first converter station is controlled to lock the converter and output a prompt message, including: When both the second current difference and the third current difference are greater than the first threshold, and the duration for which the fourth current difference is less than the preset second threshold is greater than the preset second duration, the first converter station is controlled to lock the converter and output a first prompt message; the first prompt message is used to indicate switching the operating mode of the second converter station.

4. The method according to claim 3, characterized in that, The switching of the second converter station's operating mode includes: When the second converter station is in bipolar operation mode, control the bipolar balanced operation of the second converter station; When the second converter station is in monopolar operation mode, control the second converter station to switch to monopolar metal operation mode.

5. The method according to claim 2, characterized in that, When the duration for which both the second current difference and the third current difference are greater than the first threshold is greater than a preset second duration, the first converter station is controlled to lock the converter and output a prompt message, including: When both the second current difference and the third current difference are greater than the first threshold, and the duration for which the fourth current difference is greater than the preset second threshold is greater than the preset second duration, the first converter station is controlled to lock the converter and output a second prompt message; the second prompt message is used to indicate the blocking of fault current from the first converter station and the second converter station.

6. The method according to claim 1, characterized in that, The process involves: acquiring the current at each current measuring point on the grounding electrode busbar again, recalculating the deviation between the current flowing into and out of each current measuring point to obtain a second current difference, calculating the deviation between the current flowing into and out of the current at the current measuring points on the two parallel branches of the grounding electrode line of the first converter station to obtain a third current difference, and then including: If the second current difference is greater than the first threshold and the third current difference is less than the first threshold, the converter of the first converter station is locked.

7. A grounding busbar protection device for a shared grounding electrode converter station, wherein a first converter station is connected to a target grounding electrode via a grounding busbar, and the target grounding electrode is also connected to a second converter station, the first converter station comprising a first electrode and a second electrode, characterized in that, The device includes: The first processing module is used to acquire the current at each current measuring point on the grounding electrode bus, and calculate the deviation between the current flowing into and out of each current measuring point to obtain a first current difference value; each current measuring point is located at least on two parallel branches on the DC neutral bus of the first pole, the DC neutral bus of the second pole, the in-station grounding point of the first converter station, and the grounding electrode line of the first converter station. The first control module is used to control the bipolar balanced operation of the first converter station when the duration of the first current difference being greater than a preset first threshold is greater than a preset first duration. The second processing module is used to acquire the current of each current measuring point on the grounding electrode busbar again, and recalculate the deviation between the current flowing into and out of each current measuring point to obtain the second current difference value. It also calculates the deviation between the current flowing into and out of the current on the two branches connected in parallel in the grounding electrode line of the first converter station to obtain the third current difference value. The second control module is used to control the first converter station to lock the converter and output a prompt message when the duration for which both the second current difference and the third current difference are greater than the first threshold is greater than a preset second duration; the prompt message is used to indicate the blocking of fault current from the second converter station.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

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

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

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