DC Resonance Suppression Method, Device, Equipment and Storage Medium for DC Transmission System

Abstract

The present application provides a method, device, equipment and storage medium for suppressing DC resonance in a DC power transmission system, which acquires the DC side current of the DC power transmission system and determines the harmonic current at the resonance point from the DC side current based on the operation mode of the DC power transmission system; calculates the rising rate of the DC current difference of the harmonic current within a preset time interval; when the DC side current is greater than a first preset threshold and the number of times that the rising rate of the DC current difference is greater than a second preset threshold within a preset time period is greater than a preset number of times, it is determined that resonance occurs on the DC side of the DC power transmission system; when the current of the DC filter disconnector on the rectifier side of the DC power transmission system does not exceed a preset limit value, the DC filter is removed to suppress resonance. When it is determined that resonance occurs on the DC side, the method changes the impedance characteristics of the DC side by removing the DC filter so as to destroy the resonance. This method can quickly and accurately determine and suppress resonance.

Description

Technical Field

[0001] The present application relates to the technical field of DC resonance suppression, and particularly relates to a method, device, equipment, and storage medium for suppressing DC resonance in a DC power transmission system. Background Art

[0002] A DC power transmission system is composed of the power electronic inverter side, and the operation of the inverter side mainly depends on the control system. The introduction of the control system may cause negative damping in the entire DC power transmission system. Especially in the case of relatively low primary impedance, it will increase the weak damping or negative damping of the DC power transmission system, resulting in resonance amplification rather than attenuation of the DC power transmission system under disturbance conditions. The DC side voltage of a conventional DC power transmission system is related to the AC side voltage. Usually, the AC side voltage changes little, so the DC side can be regarded as a harmonic voltage source. Then, when scanning for resonance in the DC loop, the low impedance point in parallel is usually concerned to prevent large harmonic currents from appearing on the DC side. However, in the actual operation of the DC power transmission system, there are still resonance oscillations on the DC side caused by the negative damping effect of the control system.

[0003] Currently, the resonance risk of the DC side loop is high, and the occurrence of resonance is often random and under extreme transient conditions, such as lightning strikes, faults, etc., which cause the DC side control system to enter an unstable operating point, thereby exciting resonance. Therefore, it is particularly important to suppress DC resonance. Currently, there is no relevant method for suppressing DC resonance. Summary of the Invention

[0004] In view of this, the embodiments of the present application provide a method, device, equipment, and storage medium for suppressing DC resonance in a DC power transmission system.

[0005] In a first aspect, the embodiments of the present application provide a method for suppressing DC resonance in a DC power transmission system, the method including:

[0006] Obtain the DC side current of the DC power transmission system, and determine the harmonic current at the resonance point from the DC side current based on the operation mode of the DC power transmission system;

[0007] Calculate the rising rate of the DC current difference of the harmonic current within a preset time interval;

[0008] When the DC side current is greater than a first preset threshold, and the number of times that the rising rate of the DC current difference is greater than a second preset threshold within a preset time period is greater than a preset number of times, it is determined that resonance occurs on the DC side of the DC power transmission system;

[0009] When the current of the DC filter disconnector on the rectifier side of the DC power transmission system does not exceed a preset limit value, disconnect the DC filter to suppress resonance.

[0010] Second aspect, an embodiment of the present application provides a DC resonance suppression device for a DC power transmission system, the device includes:

[0011] A DC side current acquisition module, configured to acquire the DC side current of the DC power transmission system;

[0012] A harmonic current determination module, configured to determine the harmonic current at the resonance point from the DC side current based on the operation mode of the DC power transmission system;

[0013] A difference rising rate calculation module, configured to calculate the rising rate of the DC current difference of the harmonic current within a preset time interval;

[0014] A resonance determination module, configured to determine that resonance occurs on the DC side of the DC power transmission system when the DC side current is greater than a first preset threshold and the number of times that the rising rate of the DC current difference is greater than a second preset threshold within a preset time period is greater than a preset number of times;

[0015] A DC filter cut-off module, configured to cut off the DC filter to suppress resonance when the current of the DC filter disconnector on the rectifier side of the DC power transmission system does not exceed a preset limit value.

[0016] Third aspect, an embodiment of the present application provides a terminal device, including: a memory; one or more processors, coupled to the memory; one or more application programs, wherein, one or more application programs are stored in the memory and configured to be executed by one or more processors, and one or more application programs are configured to execute the DC resonance suppression method for the DC power transmission system provided in the first aspect above.

[0017] Fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which program code is stored, and the program code can be called by a processor to execute the DC resonance suppression method for the DC power transmission system provided in the first aspect above.

[0018] The DC resonance suppression method, device, equipment and storage medium provided by the embodiments of the present application first acquire the DC side current of the DC power transmission system, and determine the harmonic current at the resonance point from the DC side current based on the operation mode of the DC power transmission system; then calculate the rising rate of the DC current difference of the harmonic current within a preset time interval; when the DC side current is greater than a first preset threshold and the number of times that the rising rate of the DC current difference is greater than a second preset threshold within a preset time period is greater than a preset number of times, determine that resonance occurs on the DC side of the DC power transmission system; when the current of the DC filter disconnector on the rectifier side of the DC power transmission system does not exceed a preset limit value, cut off the DC filter to suppress resonance.

[0019] The DC resonance suppression method provided by the embodiment of the present application, when it is determined that resonance occurs on the DC side, changes the impedance characteristics of the DC side by removing the DC filter to destroy the resonance. This method can quickly and accurately determine and suppress resonance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without creative efforts.

[0021] Figure 1 It is a schematic diagram of the application scenario of the DC resonance suppression method for the DC transmission system provided by the embodiment of the present application;

[0022] Figure 2 It is a schematic flowchart of the DC resonance suppression method for the DC transmission system provided by an embodiment of the present application;

[0023] Figure 3 It is a structural diagram of the DC resonance suppression device for the DC transmission system provided by an embodiment of the present application;

[0024] Figure 4 It is a schematic structural diagram of the terminal device provided by an embodiment of the present application;

[0025] Figure 5 It is a schematic structural diagram of the computer-readable storage medium provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0027] In order to describe the present application in more detail, the following will specifically describe a DC resonance suppression method, device, terminal device, and computer storage medium provided by the present application with reference to the drawings.

[0028] Please refer to Figure 1 , Figure 1FIG. 0 shows a schematic diagram of an application scenario of the DC resonance suppression method for a DC power transmission system provided by an embodiment of the present application. This application scenario includes a terminal device 100 provided by an embodiment of the present application. The terminal device 100 can be various electronic devices with a display screen (such as the structural diagrams of 102, 104, 106, and 108), including but not limited to smartphones and computer devices. Among them, the computer device can be at least one of devices such as a desktop computer, a portable computer, a laptop computer, and a tablet computer. A user operates the terminal device 100 to issue an operation instruction for suppressing DC resonance in the DC power transmission system. The terminal device 100 executes the DC resonance suppression method for the DC power transmission system of the present application. For the specific process, please refer to the embodiment of the DC resonance suppression method for the DC power transmission system.

[0029] Secondly, the terminal device 100 can generally refer to one of multiple terminal devices. In this embodiment, only the terminal device 100 is used as an example for illustration. Those skilled in the art can understand that the number of the above terminal devices can be more or less. For example, the above terminal devices can be only a few, or the above terminal devices can be dozens or hundreds, or a larger number. The embodiment of the present application does not limit the number and type of the terminal devices. The terminal device 100 can be used to execute a DC resonance suppression method provided in an embodiment of the present application.

[0030] In an alternative embodiment, in addition to the terminal device 100 provided by an embodiment of the present application, this application scenario may further include a server, where a network is provided between the server and the terminal device. The network is used as a medium for providing a communication link between the terminal device and the server. The network can include various connection types, such as wired, wireless communication links, or fiber optic cables, etc.

[0031] It should be understood that the numbers of the terminal device, the network, and the server are only illustrative. According to the implementation requirements, there can be any number of terminal devices, networks, and servers. For example, the server can be a server cluster composed of multiple servers, etc. Among them, the terminal device interacts with the server through the network to receive or send messages, etc. The server can be a server that provides various services. The server can be used to execute the steps of a DC resonance suppression method provided in an embodiment of the present application. In addition, when the terminal device executes a DC resonance suppression method provided in an embodiment of the present application, some steps can be executed on the terminal device, and some steps can be executed on the server, which is not limited here.

[0032] Based on this, an embodiment of the present application provides a DC resonance suppression method for a DC power transmission system. Please refer to Figure 2 , Figure 2 FIG. shows a schematic flowchart of a DC resonance suppression method for a DC power transmission system provided by an embodiment of the present application. Taking this method as applied toFigure 1 Taking the terminal device in

[0033] Step S110: Obtain the DC - side current of the HVDC system, and determine the harmonic current at the resonance point from the DC - side current based on the operation mode of the HVDC system.

[0034] Among them, there are various operation modes of the HVDC system, including but not limited to bipolar operation, monopole - to - ground, monopole - metal, etc. Different operation modes have different resonance points, that is, different resonance frequencies. In this embodiment, it means screening out the harmonic current corresponding to the resonance frequency according to different operation modes.

[0035] Harmonic current is a general term for the sine components whose frequencies are integer multiples of the original periodic current frequency when the non - sinusoidal periodic current function is expanded by Fourier series.

[0036] Step S120: Calculate the rising rate of the DC - current difference of the harmonic current within a preset time interval.

[0037] The rising rate of the DC - current difference refers to the ratio of the DC - current difference within a preset time interval to the preset time interval. Its calculation method is to determine the DC - current difference within the preset time interval according to the harmonic current; calculate the ratio of the DC - current difference to the preset time interval to obtain the rising rate of the DC - current difference.

[0038] Among them, the rising rate of the DC - current difference can be expressed by the following formula:

[0039]

[0040] Δt refers to the preset time interval, and ΔI(t) refers to the DC - current difference within the preset time interval; represents the rising rate of the DC - current difference within the preset time interval; I0(t) represents the harmonic current at time t, and I0(t - Δt) represents the harmonic current at time t - Δt.

[0041] Step S130: When the DC - side current is greater than the first preset threshold, and the number of times that the rising rate of the DC - current difference is greater than the second preset threshold within a preset time period is greater than the preset number of times, it is determined that resonance occurs on the DC - side of the HVDC system.

[0042] Among them, the first preset threshold, the second preset threshold, the preset time period, and the preset number of times are all pre - set values. When the DC - current on the DC - side is greater than the first preset threshold, it means that the DC - side current exceeds the protection warning value, and at this time, an alarm notification will be sent. Before the alarm notification, judge whether the number of times within the preset time period (that is, a period of time) (that is, the second preset threshold) is greater than the preset number of times N. If so, it is judged that resonance occurs on the DC - side.

[0043] Step S140: When the current of the DC filter disconnector on the rectifier side of the HVDC transmission system does not exceed the preset limit, the DC filter is removed to suppress resonance.

[0044] After determining that resonance occurs on the DC side, it is necessary to suppress the resonance. Specifically, first judge whether the current of the DC filter disconnector on the rectifier side of the HVDC transmission system exceeds the preset limit. If it does not exceed, the DC filter can be removed to change the impedance characteristics on the DC side and thus destroy or suppress the resonance.

[0045] It should be noted that the preset limit is usually a pre-set value, for example, it can be 100A.

[0046] In addition, the following explanations are made regarding the DC side, rectifier side, and inverter side. The HVDC transmission system rectifies alternating current into direct current, and the converter station that specifically performs this is called the rectifier side; the direct current is transmitted through the line to the target location, where the direct current is inverted back into alternating current, and the converter station that specifically performs this is called the inverter side. The part that transmits direct current in the middle is called the DC side.

[0047] The method for suppressing DC resonance in the HVDC transmission system provided by the embodiment of the present application first obtains the DC side current of the HVDC transmission system, and determines the harmonic current at the resonance point from the DC side current based on the operation mode of the HVDC transmission system; then calculates the rising rate of the DC current difference of the harmonic current within a preset time interval; when the DC side current is greater than the first preset threshold, and the number of times the rising rate of the DC current difference is greater than the second preset threshold within a preset time period is greater than the preset number of times, it is determined that resonance occurs on the DC side of the HVDC transmission system; when the current of the DC filter disconnector on the rectifier side of the HVDC transmission system does not exceed the preset limit, the DC filter is removed to suppress resonance.

[0048] The method for suppressing DC resonance in the HVDC transmission system provided by this embodiment, when it is determined that resonance occurs on the DC side, changes the impedance characteristics on the DC side by removing the DC filter to destroy the resonance. This method can quickly and accurately determine and suppress resonance.

[0049] Furthermore, several specific implementation manners for removing the DC filter are given and described as follows:

[0050] In one of the implementation manners, removing the DC filter includes: when the DC filter is a bipolar DC filter and both are in operation, select the pole of the bipolar DC filter with fewer removal times for removal.

[0051] Specifically, when the DC filter on the DC side is a bipolar DC filter, first determine whether each pole of the bipolar DC filter is in operation or use. If both are in use, the pole of the DC filter with fewer cut-off times can be selected for cut-off, that is, the DC filter that is easy to cut off can be selected for cut-off. Among them, the cut-off times can refer to the cut-off quantity of the DC filter recorded within a period of time, or the number of disconnector operations when the DC filter is cut off. By using this method, the DC filter can be quickly cut off, thereby suppressing resonance.

[0052] In another embodiment, cutting off the DC filter includes: when the DC filter is a bipolar DC filter and both are in operation, and the cut-off times of each pole of the bipolar DC filter are the same, cut off any one pole of the DC filter.

[0053] Specifically, when the bipolar DC filters are both in operation and the cut-off times are the same, it means that the difficulty of cutting off the bipolar DC filters is similar, then any one pole of the DC filter can be arbitrarily selected for cutting off.

[0054] Next, an embodiment of suppressing resonance is also given, which is described in detail as follows:

[0055] In one embodiment, the method for suppressing DC resonance in a DC power transmission system further includes: when the current of the disconnector of the DC filter on the rectifier side of the DC power transmission system exceeds a preset limit value, phase shift and blocking are sequentially performed on the inverter side and the rectifier side to suppress resonance.

[0056] In one embodiment, sequentially performing phase shift and blocking on the inverter side and the rectifier side includes: first performing phase shift and blocking on the inverter side, and after a preset time interval, performing phase shift and blocking on the rectifier side.

[0057] In one embodiment, after sequentially performing phase shift and blocking on the inverter side and the rectifier side, it includes: restarting the monopole on the DC side.

[0058] Specifically, when the current of the disconnector of the DC filter on the rectifier side of the DC power transmission system exceeds the preset limit value, phase shift and blocking can be performed on the inverter side, and then the rectifier side is blocked. Among them, after performing phase shift and blocking on the inverter side, phase shift and blocking can be immediately performed on the rectifier side; or after performing phase shift and blocking on the inverter side first, phase shift and blocking are performed on the rectifier side after a period of time (for example, about 100 ms).

[0059] After blocking the rectifier side, after a preset time interval (for example, 500 ms), the DC monopole on the DC side can be restarted.

[0060] In this embodiment, resonance on the DC side caused by extreme faults can be well suppressed by means of DC restart.

[0061] It should be understood that, although Figure 2 the steps in the flowchart are shown in sequence according to the indication of the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear description in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover Figure 2 at least a part of the steps in

[0062] include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same moment, but can be executed at different moments, and the execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or in turn with at least a part of other steps or sub-steps or stages of other steps.

[0063] Please refer to Figure 3 , which is a DC resonance suppression device for a DC transmission system disclosed in an embodiment of the present application, mainly including:

[0064] A DC side current acquisition module 310, configured to acquire the DC side current of the DC transmission system.

[0065] A harmonic current determination module 320, configured to determine the harmonic current at the resonance point from the DC side current based on the operation mode of the DC transmission system.

[0066] A difference rising rate calculation module 330, configured to calculate the rising rate of the DC current difference of the harmonic current within a preset time interval.

[0067] A resonance determination module 340, configured to determine that resonance occurs on the DC side of the DC transmission system when the DC side current is greater than a first preset threshold and the number of times that the rising rate of the DC current difference is greater than a second preset threshold within a preset time period is greater than a preset number of times.

[0068] A DC filter cut-off module 350, configured to cut off the DC filter to suppress resonance when the current of the DC filter disconnector on the rectifier side of the DC transmission system does not exceed a preset limit value.

[0069] In one embodiment, the DC filter cut-off module 350 is configured to, when the DC filter is a bipolar DC filter and both are in operation, select the pole of the bipolar DC filter with fewer cut-off times for cut-off.

[0070] In one embodiment, the DC filter cut-off module 350 is configured to cut off any one pole of the DC filter when the DC filter is a bipolar DC filter and both poles are in operation, and the cut-off times of the DC filters of each pole in the bipolar DC filter are the same.

[0071] In one embodiment, the device further includes: a blocking module, configured to perform phase-shift blocking on the inverter side and the rectifier side in sequence when the current of the DC filter disconnector on the rectifier side of the DC transmission system exceeds a preset limit value, so as to suppress resonance.

[0072] In one embodiment, the blocking module is configured to first perform phase-shift blocking on the inverter side, and after a preset time interval, perform phase-shift blocking on the rectifier side.

[0073] In one embodiment, the device further includes: a restart module, configured to perform single-pole restart on the DC side.

[0074] In one embodiment, the difference rising rate calculation module 330 is configured to determine the DC current difference within a preset time interval according to the harmonic current; calculate the ratio of the DC current difference to the preset time interval to obtain the DC current difference rising rate.

[0075] For the specific limitations of the DC resonance suppression device of the DC transmission system, reference may be made to the limitations on the method in the foregoing text, which will not be elaborated herein. Each module in the above device can be implemented in whole or in part by software, hardware, and their combination. The above modules can be embedded in the processor in the terminal device in hardware form or be independent of it, or can be stored in the memory in the terminal device in software form, so that the processor can call and execute the operations corresponding to the above modules.

[0076] Please refer to Figure 4 , Figure 4 which shows a structural block diagram of a terminal device provided by an embodiment of the present application. The terminal device 40 may be a computer device. The terminal device 40 in the present application may include one or more of the following components: a processor 42, a memory 44, and one or more application programs, where one or more application programs may be stored in the memory 44 and configured to be executed by one or more processors 42, and one or more application programs are configured to execute the methods described in the embodiments of the DC resonance suppression method of the DC transmission system.

[0077] The processor 42 may include one or more processing cores. The processor 42 connects various parts within the entire terminal device 40 through various interfaces and circuits. By running or executing instructions, programs, code sets, or instruction sets stored in the memory 44, and by invoking the data stored in the memory 44, it performs various functions of the terminal device 40 and processes data. Optionally, the processor 42 may be implemented in at least one hardware form of digital signal processing (DSP), field-programmable gate array (FPGA), or programmable logic array (PLA). The processor 42 may integrate a central processing unit (CPU), a graphics processing unit (GPU) for reporting and verifying buried-point data, a modem, etc., in one or several combinations. Among them, the CPU mainly processes the operating system, user interface, application programs, etc.; the GPU is responsible for rendering and drawing display content; the modem is used to process wireless communication. It can be understood that the above-mentioned modem may not be integrated into the processor 42 and may be implemented separately through a communication chip.

[0078] The memory 44 may include random access memory (RAM) and may also include read-only memory. The memory 44 can be used to store instructions, programs, code, code sets, or instruction sets. The memory 44 may include a program storage area and a data storage area. Among them, the program storage area may store instructions for implementing the operating system, instructions for implementing at least one function (such as touch function, sound playback function, image playback function, etc.), instructions for implementing the following various method embodiments, etc. The data storage area may also store data created during the use of the terminal device 40.

[0079] Those skilled in the art can understand that Figure 4 the structure shown in

[0080] merely represents a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the terminal device to which the solution of this application is applied. The specific terminal device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0081] Please refer to Figure 5, which shows a structural block diagram of a computer-readable storage medium provided by an embodiment of the present application. Program code is stored in the computer-readable storage medium 50, and the program code can be called by a processor to execute the method described in the embodiment of the DC resonance suppression method for a DC power transmission system.

[0082] The computer-readable storage medium 50 can be an electronic memory such as a flash memory, an EEPROM (electrically erasable programmable read-only memory), an EPROM, a hard disk, or a ROM. Optionally, the computer-readable storage medium 50 includes a non-transitory computer-readable storage medium. The computer-readable storage medium 50 has a storage space for the program code 52 that executes any method step in the above method. These program codes can be read out from or written into one or more computer program products. The program code 52 can be compressed in an appropriate form, for example.

[0083] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0084] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for suppressing DC resonance in a DC power transmission system, characterized in that, The method includes: Obtaining the DC - side current of the HVDC transmission system, and determining the harmonic current at the resonance point from the DC - side current based on the operation mode of the HVDC transmission system; Calculating the current difference rising rate of the harmonic current within a preset time interval; When the DC - side current is greater than a first preset threshold, and the number of times the current difference rising rate is greater than a second preset threshold within a preset time period is greater than a preset number, it is determined that resonance occurs on the DC - side of the HVDC transmission system; When the current of the DC filter disconnector on the rectifier side of the HVDC transmission system does not exceed a preset limit value, removing the DC filter to suppress resonance.

2. The method according to claim 1, wherein The removing the DC filter includes: When the DC filter is a bipolar DC filter and both are in operation, selecting the pole of the bipolar DC filter with fewer removal times for removal.

3. The method according to claim 1, wherein The removing the DC filter includes: When the DC filter is a bipolar DC filter and both are in operation, and the removal times of each pole of the bipolar DC filter are the same, removing any one pole of the DC filter.

4. The method according to any one of claims 1-3, characterized in that, The method further includes: When the current of the DC filter disconnector on the rectifier side of the HVDC transmission system exceeds a preset limit value, performing phase - shift locking on the inverter side and the rectifier side in sequence to suppress resonance.

5. The method according to claim 4, characterized in that The performing phase - shift locking on the inverter side and the rectifier side in sequence includes: First performing phase - shift locking on the inverter side, and after a preset time interval, performing phase - shift locking on the rectifier side.

6. The method according to claim 4, wherein After the performing phase - shift locking on the inverter side and the rectifier side in sequence, it includes: Performing single - pole restart on the DC - side.

7. The method according to claim 4, characterized in that The calculating the current difference rising rate of the harmonic current within a preset time interval includes: Determining the current difference within the preset time interval according to the harmonic current; Calculating the ratio of the current difference to the preset time interval to obtain the current difference rising rate.

8. A DC resonance suppression device for a DC power transmission system, characterized in that, The device includes: A DC - side current acquisition module for obtaining the DC - side current of the HVDC transmission system; A harmonic current determination module for determining the harmonic current at the resonance point from the DC - side current based on the operation mode of the HVDC transmission system; A difference rising rate calculation module for calculating the current difference rising rate of the harmonic current within a preset time interval; A resonance determination module for determining that resonance occurs on the DC - side of the HVDC transmission system when the DC - side current is greater than a first preset threshold, and the number of times the current difference rising rate is greater than a second preset threshold within a preset time period is greater than a preset number; A DC filter removal module for removing the DC filter to suppress resonance when the current of the DC filter disconnector on the rectifier side of the HVDC transmission system does not exceed a preset limit value.

9. A terminal device, characterized in that, It includes: A memory; One or more processors coupled to the memory; One or more applications, wherein one or more applications are stored in the memory and configured to be executed by one or more processors, and one or more applications are configured to execute the method according to any one of claims 1 - 7.

10. A computer-readable storage medium, characterized in that, The computer - readable storage medium stores program codes, and the program codes can be called by the processor to execute the method according to any one of claims 1 - 7.

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