Overvoltage threshold self-adaptive adjustment protection method and device for IGCT (integrated gate commutated thyristor)

Abstract

The invention relates to the technical field of high-voltage direct-current transmission, and particularly provides an overvoltage threshold self-adaptive adjustment protection method and device for an IGCT (integrated gate commutation current transformer), and the method comprises the steps: obtaining the real-time terminal voltage of a sub-module of a hybrid commutation current converter and the operation condition of the IGCT in the sub-module; and adjusting the overvoltage protection threshold of the IGCT in the sub-module of the hybrid commutation converter based on the real-time terminal voltage of the sub-module of the hybrid commutation converter and the operation condition of the IGCT in the sub-module. According to the technical scheme provided by the invention, a fuse can be omitted, the operation reliability of the converter valve is improved, the technical blank of related protection strategies of the lightning arrester of the hybrid commutation converter valve assembly is filled, and a reference basis is provided for the design of an engineering control protection system.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage direct current transmission, and in particular to an IGCT overvoltage threshold adaptive regulation protection method and device. Background Art

[0002] High-voltage direct current (HVDC) transmission technology based on line commutated converters (LCC-HVDC) boasts advantages such as large transmission capacity, long distances, high efficiency, low losses, and a small footprint, and is widely used worldwide. However, due to the semi-controlled nature of the thyristor, the fundamental component, when the AC voltage at the receiving-end converter station of an LCC-HVDC system distorts or drops due to AC system faults or other factors, the thyristors cannot reliably shut down, resulting in commutation failure in the converter. This is a unique failure mode of conventional LCC converters. To address commutation failure, a hybrid commutated converter (HCC) technology based on reverse-resistance IGCT (Integrated Gate-Commutated Thyristor) has been proposed. Unlike traditional LCCs, the HCC is essentially a combination of an LCC and a circuit breaker. When operating without triggering a lightning arrester and when the lightning arrester only serves to protect against shock, the HCC is equivalent to an LCC. However, when a fault on the AC side causes a voltage drop and commutation failure is imminent, the HCC needs to function as a circuit breaker, cutting off the current in its own arm and forcing it to commutate to the adjacent arm to complete commutation, thereby preventing commutation failure.

[0003] However, due to the large number of IGCT devices in the HCC connected in series and facing the high current shutdown condition, the voltage stress at both ends of the device is relatively harsh. The RC voltage equalization circuit of the conventional LCC is difficult to ensure the voltage equalization of a large number of direct-series devices, which can easily lead to the IGCT devices being broken down by the shutdown spike voltage. In order to overcome the voltage equalization problem of a large number of direct-series IGCT devices, discrete component lightning arresters are often used to protect a certain number of devices, that is, a component lightning arrester is connected in parallel with two IGCT devices and their dynamic and static voltage equalization circuits (hereinafter referred to as sub-modules). However, when the IGCT cannot be triggered to turn on normally due to communication failures, the bridge arm current will flow through the sub-module lightning arrester for a long time, causing abnormal energy absorption of the lightning arrester, which will be damaged to its energy limit and even affect the normal operation of the converter valve.

[0004] To prevent IGCT damage from overvoltage breakdown, existing technology uses a lightning arrester connected in series with a fuse and then connected in parallel with a single-stage IGCT. Alternatively, a lightning arrester connected in series with a fuse and then connected in parallel with a two-stage IGCT. If an overvoltage condition occurs in the entire module, the fuse immediately blows to prevent the lightning arrester from absorbing excessive energy. The introduction of fuses increases the risk and complexity of the converter valve, reducing reliability. Summary of the Invention

[0005] In order to overcome the above-mentioned defects, the present invention proposes a method and device for adaptively adjusting the overvoltage threshold protection of an IGCT.

[0006] In a first aspect, a method for adaptively adjusting an overvoltage threshold value of an IGCT for protection is provided. The method for adaptively adjusting an overvoltage threshold value of an IGCT for protection comprises:

[0007] Obtaining the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule;

[0008] An overvoltage protection threshold of the IGCT in the submodule of the hybrid commutation converter is adjusted based on the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule.

[0009] Preferably, the adjusting the overvoltage protection threshold of the IGCT in the submodule of the hybrid commutation converter based on the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule includes:

[0010] When the 2-level IGCT in the submodule of the hybrid commutation converter cannot be turned on normally and the real-time terminal voltage of the submodule of the hybrid commutation converter exceeds 2U for X consecutive cycles FOPI When the overvoltage protection threshold of the second-level IGCT is simultaneously reduced to U FOPII ;

[0011] When any IGCT in the submodule of the hybrid commutation converter fails to conduct normally and the Y-cycle real-time terminal voltage of any IGCT exceeds U FOPI When the overvoltage protection threshold of any level IGCT is reduced to U FOPI ;

[0012] Among them, U FOPI is the overvoltage level of the IGCT I section, X is the first preset threshold, Y is the second preset threshold, U FOPII It is the overvoltage level of section II of IGCT.

[0013] Furthermore, the overvoltage level of section I and the overvoltage level of section II of the IGCT satisfy:

[0014] U FOPII <U op <UFOPI

[0015] U MOVc >U FOPI +U FOPII

[0016] U MOVp <2U FOPI

[0017] In the above formula, U op is the long-term design operating voltage of a single-stage IGCT, U MOVc is the reference voltage level of the component arrester, U MOVp Provides protection voltage levels for component lightning arresters.

[0018] Furthermore, the first preset threshold is as follows:

[0019] X = min(M, N)

[0020] In the above formula, M is the upper limit of the number of times the IGCT can shut down the maximum current level, and N is the upper limit of the number of times the component lightning arrester can operate.

[0021] Furthermore, the upper limit of the number of available actions of the component arrester satisfies:

[0022] N≥W / Ws

[0023] In the above formula, W is the design rated energy of the module lightning arrester, and Ws is the maximum energy absorbed by the module lightning arrester per cycle when the converter is in forced commutation shutdown mode during a system AC fault.

[0024] Preferably, the submodule of the hybrid commutation converter is composed of a component lightning arrester connected in parallel with two IGCTs and their dynamic and static voltage balancing circuits.

[0025] In a second aspect, a device for adaptively adjusting an overvoltage threshold of an IGCT is provided, wherein the device for adaptively adjusting an overvoltage threshold of an IGCT comprises:

[0026] An acquisition module, used to obtain the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule;

[0027] The regulating module is used to regulate the overvoltage protection threshold of the IGCT in the submodule of the hybrid commutation converter based on the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule.

[0028] Preferably, the adjustment module is specifically used to:

[0029] When the 2-level IGCT in the submodule of the hybrid commutation converter cannot be turned on normally and the real-time terminal voltage of the submodule of the hybrid commutation converter exceeds 2U for X consecutive cycles FOPIWhen the overvoltage protection threshold of the second-level IGCT is simultaneously reduced to U FOPII ;

[0030] When any IGCT in the submodule of the hybrid commutation converter fails to conduct normally and the Y-cycle real-time terminal voltage of any IGCT exceeds U FOPI When the overvoltage protection threshold of any level IGCT is reduced to U FOPI ;

[0031] Among them, U FOPI is the overvoltage level of the IGCT I section, X is the first preset threshold, Y is the second preset threshold, U FOPII It is the overvoltage level of section II of IGCT.

[0032] Furthermore, the overvoltage level of section I and the overvoltage level of section II of the IGCT satisfy:

[0033] U FOPII <U op <U FOPI

[0034] U MOVc >U FOPI +U FOPII

[0035] U MOVp <2U FOPI

[0036] In the above formula, U op is the long-term design operating voltage of a single-stage IGCT, U MOVc is the reference voltage level of the component arrester, U MOVp Provides protection voltage levels for component lightning arresters.

[0037] Furthermore, the first preset threshold is as follows:

[0038] X = min(M, N)

[0039] In the above formula, M is the upper limit of the number of times the IGCT can shut down the maximum current level, and N is the upper limit of the number of times the component lightning arrester can operate.

[0040] Furthermore, the upper limit of the number of available actions of the component arrester satisfies:

[0041] N≥W / Ws

[0042] In the above formula, W is the design rated energy of the module lightning arrester, and Ws is the maximum energy absorbed by the module lightning arrester per cycle when the converter is in forced commutation shutdown mode during a system AC fault.

[0043] Preferably, the submodule of the hybrid commutation converter is composed of a component lightning arrester connected in parallel with two IGCTs and their dynamic and static voltage balancing circuits.

[0044] In a third aspect, a computer device is provided, comprising: one or more processors;

[0045] The processor is configured to execute one or more programs;

[0046] When the one or more programs are executed by the one or more processors, the IGCT overvoltage threshold adaptive adjustment protection method is implemented.

[0047] In a fourth aspect, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed, the IGCT overvoltage threshold adaptive adjustment protection method is implemented.

[0048] In a fifth aspect, a hybrid commutation converter is provided, wherein the IGCT in the hybrid commutation converter adopts the IGCT overvoltage threshold adaptive adjustment protection method to perform overvoltage threshold adaptive adjustment protection.

[0049] The above one or more technical solutions of the present invention have at least one or more of the following beneficial effects:

[0050] The present invention provides a method and device for adaptively adjusting the overvoltage threshold protection of an IGCT, comprising: obtaining the real-time terminal voltage of a submodule of a hybrid commutation converter and the operating status of the IGCT within the submodule; and adjusting the overvoltage protection threshold of the IGCT within the submodule of the hybrid commutation converter based on the real-time terminal voltage of the submodule and the operating status of the IGCT within the submodule. The technical solution provided by the present invention not only eliminates the need for fuses, thereby improving the operational reliability of the converter valve, but also fills a technical gap in the protection strategy for lightning arresters in hybrid commutation converter valve assemblies, providing a reference for the design of engineering control and protection systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 1 is a flow chart showing the main steps of the method for adaptively adjusting the overvoltage threshold protection of an IGCT according to an embodiment of the present invention;

[0052] Figure 2 2. It is a topological structure diagram of a hybrid phase-commutated converter valve according to an embodiment of the present invention;

[0053] Figure 3 It is a principle diagram of the working mode of the hybrid phase-commutated converter valve according to an embodiment of the present invention. DETAILED DESCRIPTION

[0054] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0056] As disclosed in the background, line commutated converter (LCC-HVDC) high-voltage direct current (HVDC) transmission technology based on line commutated converters (LCC-HVDC) boasts advantages such as large transmission capacity, long distances, high efficiency, low losses, and minimal footprint, and is widely used worldwide. Due to the semi-controlled nature of the thyristor, the fundamental component, when the AC voltage at the receiving-end converter station of an LCC-HVDC system distorts or drops due to an AC system fault or other reason, the thyristor cannot reliably shut down, resulting in commutation failure in the converter. This is a unique failure mode of conventional LCC converters. To address the commutation failure problem, a hybrid commutated converter (HCC) technology based on reverse-resistance IGCT (Integrated Gate-Commutated Thyristor) has been proposed. Unlike traditional LCCs, the HCC is essentially a combination of an LCC and a circuit breaker. When operating without triggering a lightning arrester and when the lightning arrester only serves to protect against shock, the HCC is equivalent to an LCC. However, when a fault on the AC side causes a voltage drop and commutation failure is imminent, the HCC needs to function as a circuit breaker, cutting off the current in its own arm and forcing it to commutate to the adjacent arm to complete commutation, thereby preventing commutation failure.

[0057] However, due to the large number of IGCT devices in the HCC connected in series and facing the high current shutdown condition, the voltage stress at both ends of the device is relatively harsh. The RC voltage equalization circuit of the conventional LCC is difficult to ensure the voltage equalization of a large number of direct-series devices, which can easily lead to the IGCT devices being broken down by the shutdown spike voltage. In order to overcome the voltage equalization problem of a large number of direct-series IGCT devices, discrete component lightning arresters are often used to protect a certain number of devices, that is, a component lightning arrester is connected in parallel with two IGCT devices and their dynamic and static voltage equalization circuits (hereinafter referred to as sub-modules). However, when the IGCT cannot be triggered to turn on normally due to communication failures, the bridge arm current will flow through the sub-module lightning arrester for a long time, causing abnormal energy absorption of the lightning arrester, which will be damaged to its energy limit and even affect the normal operation of the converter valve.

[0058] To prevent IGCT damage from overvoltage breakdown, existing technology uses a lightning arrester connected in series with a fuse and then connected in parallel with a single-stage IGCT. Alternatively, a lightning arrester connected in series with a fuse and then connected in parallel with a two-stage IGCT. If an overvoltage condition occurs in the entire module, the fuse immediately blows to prevent the lightning arrester from absorbing excessive energy. The introduction of fuses increases the risk and complexity of the converter valve, reducing reliability.

[0059] To address the aforementioned issues, the present invention provides a method and device for adaptively adjusting the overvoltage threshold protection of an IGCT, comprising: obtaining the real-time terminal voltage of a hybrid commutation converter submodule and the operating status of the IGCT within the submodule; and adjusting the overvoltage protection threshold of the IGCT within the hybrid commutation converter submodule based on the real-time terminal voltage of the hybrid commutation converter submodule and the operating status of the IGCT within the submodule. The technical solution provided by the present invention not only eliminates the need for fuses, thereby improving the operational reliability of the converter valve, but also fills a technical gap in the protection strategy for lightning arresters in hybrid commutation converter valve assemblies, providing a reference for the design of engineering control and protection systems.

[0060] The above scheme is described in detail below.

[0061] Example 1

[0062] See attached Figure 1 , Figure 1 FIG. 1 is a flow chart showing the main steps of the IGCT overvoltage threshold adaptive regulation protection method according to an embodiment of the present invention. Figure 1 As shown, the IGCT overvoltage threshold adaptive regulation protection method in the embodiment of the present invention mainly includes the following steps:

[0063] Step S101: obtaining the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule;

[0064] Step S102: adjusting an overvoltage protection threshold of an IGCT in a submodule of the hybrid commutation converter based on the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule.

[0065] In this embodiment, the hybrid commutation converter is a current source type converter valve with active shutdown capability. Its bridge arm circuit topology is similar to that of a traditional current source type converter valve and is composed of multiple submodules connected in series. Figure 2 shown.

[0066] The submodule of the hybrid commutation converter is composed of a component lightning arrester connected in parallel with two IGCTs and their dynamic and static voltage balancing circuits.

[0067] The HCC converter valve has two working modes:

[0068] Recovery-enhanced natural commutation mode: It can reduce the equivalent reverse recovery time of the device to microseconds, ensuring reliable commutation under normal working conditions and shallow fault conditions. In this mode, the IGCT does not actively shut down the current or shuts down a small current, such as Figure 3 As shown in A;

[0069] Forced commutation mode: Utilize the IGCT's repeated shutoff capability to actively shut down the bridge arm current, achieve rapid commutation under deep fault conditions, and resist the risk of commutation failure in the LCC converter valve. In this mode, the IGCT generally needs to shut down a large current, such as Figure 3 As shown in B.

[0070] In this embodiment, adjusting the overvoltage protection threshold of the IGCT in the submodule of the hybrid commutation converter based on the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule includes:

[0071] When the 2-level IGCT in the submodule of the hybrid commutation converter cannot be turned on normally and the real-time terminal voltage of the submodule of the hybrid commutation converter exceeds 2U for X consecutive cycles FOPI When the overvoltage protection threshold of the second-level IGCT is simultaneously reduced to U FOPII ;

[0072] When any IGCT in the submodule of the hybrid commutation converter fails to conduct normally and the Y-cycle real-time terminal voltage of any IGCT exceeds U FOPI When the overvoltage protection threshold of any level IGCT is reduced to U FOPI ;

[0073] Among them, U FOPI is the overvoltage level of the IGCT I section, X is the first preset threshold, Y is the second preset threshold, the value of Y depends on the tolerance of the IGCT dynamic voltage equalizing circuit, U FOPII It is the overvoltage level of section II of IGCT.

[0074] In one embodiment, the overvoltage level of section I and the overvoltage level of section II of the IGCT satisfy:

[0075] U FOPII <U op <U FOPI

[0076] U MOVc >U FOPI +U FOPII

[0077] U MOVp <2U FOPI

[0078] In the above formula, U opis the long-term design operating voltage of a single-stage IGCT, U MOVc is the reference voltage level of the component arrester, U MOVp Provides protection voltage levels for component lightning arresters.

[0079] In one embodiment, the first preset threshold is as follows:

[0080] X = min(M, N)

[0081] In the above formula, M is the upper limit of the number of times the IGCT can shut down the maximum current level, and N is the upper limit of the number of times the component lightning arrester can operate.

[0082] In one embodiment, the upper limit of the number of available operations of the component arrester satisfies:

[0083] N≥W / Ws

[0084] In the above formula, W is the design rated energy of the module lightning arrester, and Ws is the maximum energy absorbed by the module lightning arrester per cycle when the converter is in forced commutation shutdown mode during a system AC fault.

[0085] Example 2

[0086] Based on the same inventive concept, the present invention further provides an IGCT overvoltage threshold adaptive regulation protection device, the IGCT overvoltage threshold adaptive regulation protection device comprising:

[0087] An acquisition module, used to obtain the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule;

[0088] The regulating module is used to regulate the overvoltage protection threshold of the IGCT in the submodule of the hybrid commutation converter based on the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule.

[0089] Preferably, the adjustment module is specifically used to:

[0090] When the 2-level IGCT in the submodule of the hybrid commutation converter cannot be turned on normally and the real-time terminal voltage of the submodule of the hybrid commutation converter exceeds 2U for X consecutive cycles FOPI When the overvoltage protection threshold of the second-level IGCT is simultaneously reduced to U FOPII ;

[0091] When any IGCT in the submodule of the hybrid commutation converter fails to conduct normally and the Y-cycle real-time terminal voltage of any IGCT exceeds U FOPI When the overvoltage protection threshold of any level IGCT is reduced to U FOPI ;

[0092] Among them, U FOPIis the overvoltage level of the IGCT I section, X is the first preset threshold, Y is the second preset threshold, U FOPII It is the overvoltage level of section II of IGCT.

[0093] Furthermore, the overvoltage level of section I and the overvoltage level of section II of the IGCT satisfy:

[0094] U FOPII <U op <U FOPI

[0095] U MOVc >U FOPI +U FOPII

[0096] U MOVp <2U FOPI

[0097] In the above formula, U op is the long-term design operating voltage of a single-stage IGCT, U MOVc is the reference voltage level of the component arrester, U MOVp Provides protection voltage levels for component lightning arresters.

[0098] Furthermore, the first preset threshold is as follows:

[0099] X = min(M, N)

[0100] In the above formula, M is the upper limit of the number of times the IGCT can shut down the maximum current level, and N is the upper limit of the number of times the component lightning arrester can operate.

[0101] Furthermore, the upper limit of the number of available actions of the component arrester satisfies:

[0102] N≥W / Ws

[0103] In the above formula, W is the design rated energy of the module lightning arrester, and Ws is the maximum energy absorbed by the module lightning arrester per cycle when the converter is in forced commutation shutdown mode during a system AC fault.

[0104] Preferably, the submodule of the hybrid commutation converter is composed of a component lightning arrester connected in parallel with two IGCTs and their dynamic and static voltage balancing circuits.

[0105] Example 3

[0106] Based on the same inventive concept, the present invention also provides a computer device, comprising a processor and a memory, wherein the memory is configured to store a computer program, wherein the computer program includes program instructions, and the processor is configured to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc., and is the computing core and control core of the terminal. The processor is adapted to implement one or more instructions, specifically, to load and execute one or more instructions in the computer storage medium to implement a corresponding method flow or corresponding function, thereby implementing the steps of the overvoltage threshold adaptive adjustment protection method for an IGCT in the above-mentioned embodiment.

[0107] Example 4

[0108] Based on the same inventive concept, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It is understandable that the computer-readable storage medium here can include both built-in storage media in the computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space. These instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory (non-volatile memory), such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of the overvoltage threshold adaptive adjustment protection method of an IGCT in the above embodiment.

[0109] Example 5

[0110] Based on the same inventive concept, the present invention further provides a hybrid commutation converter, wherein the IGCT in the hybrid commutation converter adopts the IGCT overvoltage threshold adaptive regulation protection method to perform overvoltage threshold adaptive regulation protection.

[0111] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0112] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0113] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0114] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A method for adaptively adjusting the overvoltage threshold protection of an IGCT, characterized in that: The method comprises: Obtaining the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule; An overvoltage protection threshold of the IGCT in the submodule of the hybrid commutation converter is adjusted based on the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule.

2. The method according to claim 1, wherein The adjusting the overvoltage protection threshold of the IGCT in the submodule of the hybrid commutation converter based on the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule includes: When the 2-level IGCT in the submodule of the hybrid commutation converter cannot be turned on normally and the real-time terminal voltage of the submodule of the hybrid commutation converter exceeds 2U for X consecutive cycles FOPI When the overvoltage protection threshold of the second-level IGCT is simultaneously reduced to U FOPII ; When any IGCT in the submodule of the hybrid commutation converter fails to conduct normally and the Y-cycle real-time terminal voltage of any IGCT exceeds U FOPI When the overvoltage protection threshold of any level IGCT is reduced to U FOPI ; Among them, U FOPI is the overvoltage level of the IGCT I section, X is the first preset threshold, Y is the second preset threshold, U FOPII It is the overvoltage level of section II of IGCT.

3. The method according to claim 2, wherein The overvoltage level of section I and section II of the IGCT meet the following requirements: IN FOPII <In op <In FOPI IN MOVc >In FOPI +U FOPII And MOVp <2U FOPI In the above formula, U op is the long-term design operating voltage of a single-stage IGCT, U MOVc is the reference voltage level of the component arrester, U MOVp Provides protection voltage levels for component lightning arresters.

4. The method according to claim 2, wherein The first preset threshold is as follows: X = min(M, N) In the above formula, M is the upper limit of the number of times the IGCT can shut down the maximum current level, and N is the upper limit of the number of times the component lightning arrester can operate.

5. The method according to claim 4, wherein The upper limit of the number of available operations of the component arrester meets the following requirements: N≥W / Ws In the above formula, W is the design rated energy of the module lightning arrester, and Ws is the maximum energy absorbed by the module lightning arrester per cycle when the converter is in forced commutation shutdown mode during a system AC fault.

6. The method according to claim 1, wherein The submodule of the hybrid commutation converter is composed of a component lightning arrester connected in parallel with two IGCTs and their dynamic and static voltage balancing circuits.

7. An IGCT overvoltage threshold adaptive adjustment protection device, characterized in that: The device comprises: An acquisition module, used to obtain the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule; The regulating module is used to regulate the overvoltage protection threshold of the IGCT in the submodule of the hybrid commutation converter based on the real-time terminal voltage of the submodule of the hybrid commutation converter and the operating status of the IGCT in the submodule.

8. The device according to claim 7, wherein The adjustment module is specifically used for: When the 2-level IGCT in the submodule of the hybrid commutation converter cannot be turned on normally and the real-time terminal voltage of the submodule of the hybrid commutation converter exceeds 2U for X consecutive cycles FOPI When the overvoltage protection threshold of the second-level IGCT is simultaneously reduced to U FOPII ; When any IGCT in the submodule of the hybrid commutation converter fails to conduct normally and the Y-cycle real-time terminal voltage of any IGCT exceeds U FOPI When the overvoltage protection threshold of any level IGCT is reduced to U FOPI ; Among them, U FOPI is the overvoltage level of the IGCT I section, X is the first preset threshold, Y is the second preset threshold, U FOPII It is the overvoltage level of section II of IGCT.

9. The device according to claim 8, wherein The overvoltage level of section I and section II of the IGCT meet the following requirements: IN FOPII <In op <In FOPI IN MOVc >In FOPI +U FOPII And MOVp <2U FOPI In the above formula, U op is the long-term design operating voltage of a single-stage IGCT, U MOVc is the reference voltage level of the component arrester, U MOVp Provides protection voltage levels for component lightning arresters.

10. The device according to claim 8, wherein The first preset threshold is as follows: X = min(M, N) In the above formula, M is the upper limit of the number of times the IGCT can shut down the maximum current level, and N is the upper limit of the number of times the component lightning arrester can operate.

11. The device according to claim 10, wherein The upper limit of the number of available operations of the component arrester meets the following requirements: N≥W / Ws In the above formula, W is the design rated energy of the module lightning arrester, and Ws is the maximum energy absorbed by the module lightning arrester per cycle when the converter is in forced commutation shutdown mode during a system AC fault.

12. The device according to claim 7, wherein The submodule of the hybrid commutation converter is composed of a component lightning arrester connected in parallel with two IGCTs and their dynamic and static voltage balancing circuits.

13. A computer device, characterized in that: include: one or more processors; The processor is configured to execute one or more programs; When the one or more programs are executed by the one or more processors, the overvoltage threshold adaptive adjustment protection method for an IGCT according to any one of claims 1 to 6 is implemented.

14. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed, the overvoltage threshold adaptive adjustment protection method of the IGCT according to any one of claims 1 to 6 is implemented.

15. A hybrid commutation converter, characterized in that: The IGCT in the hybrid commutation converter adopts the IGCT overvoltage threshold adaptive adjustment protection method according to any one of claims 1 to 6 to perform overvoltage threshold adaptive adjustment protection.

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