Converter valve management and control method, device and equipment and computer readable storage medium

Abstract

The invention discloses a converter valve management and control method, device and equipment and a computer readable storage medium, and belongs to the technical field of power electronics. A first preset feature (a voltage change feature of a direct current energy storage capacitor in a power sub-module in a bypass switch off state of the power sub-module) can be set; after the power sub-module breaks down and the bypass switch is controlled to be closed, it can be judged that the bypass switch is in an open state (namely bypass failure) under the condition that the voltage value of the direct-current energy storage capacitor in the broken-down power sub-module conforms to the first preset characteristic, and therefore the converter valve is controlled to be locked, and the bypass switch is controlled to be closed. And when the bypass switch does not conform to the closed state, the bypass switch can be judged to be in the closed state (namely, the bypass is successful), and the state of the bypass switch can be accurately judged, so that the situation that the whole converter valve is locked under the condition that the bypass switch is successfully closed can be avoided, and the working efficiency of the converter valve is improved.

Description

Technical Field

[0001] The present invention relates to the field of power electronics technology, and in particular to a control method, device, equipment and computer-readable storage medium for a converter valve. Background Art

[0002] The converter valve is usually composed of multiple power sub-modules. A single power sub-module may usually include: a power electronic device (such as IGBT (Insulated-Gate Bipolar Transistor)) for controlling the state of the power sub-module, a DC energy storage capacitor for stabilizing the output voltage, and a bypass switch for bypassing the power sub-module when closed.

[0003] When a power sub-module in the converter valve fails, the bypass switch in the failed power sub-module can be controlled to close (equivalent to bypassing the failed power sub-module) so that the converter valve can continue to work. However, it is difficult to accurately determine whether the bypass switch is successfully closed in the related technology. This may result in the entire converter valve being controlled to be locked (stop working) even when the "bypass switch is successfully closed", thereby reducing the working efficiency of the converter valve.

[0004] Therefore, how to provide a solution to the above technical problems is a problem that those skilled in the art need to solve at present. Summary of the invention

[0005] The object of the present invention is to provide a control method, device, equipment and computer-readable storage medium for a converter valve. After a power sub-module fails and the bypass switch therein is controlled to close, when the voltage value of the DC energy storage capacitor in the failed power sub-module does not meet the first preset feature, it can be determined that the bypass switch is in a closed state (that is, the bypass is successful), and when it meets the first preset feature, it can be determined that the bypass switch is in an open state (that is, the bypass fails), thereby controlling the converter valve to be locked. Since the bypass switch state can be accurately determined, it is possible to avoid controlling the entire converter valve to be locked when the "bypass switch is successfully closed", thereby improving the working efficiency of the converter valve.

[0006] In order to solve the above technical problems, the present invention provides a control method of a converter valve, comprising:

[0007] When a power submodule failure occurs in the converter valve, the bypass switch in the failed power submodule is controlled to be closed;

[0008] Determine whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset feature, wherein the first preset feature refers to: the voltage change feature of the DC energy storage capacitor in the power submodule when the bypass switch of the power submodule is in the open position state;

[0009] If it is met, it is determined that the bypass switch of the faulty power submodule is in the open state, and the converter valve is controlled to be locked;

[0010] If not, it is determined that the bypass switch of the faulty power submodule is in the closed state;

[0011] The converter valve includes a plurality of power sub-modules, and the power sub-modules include: a power electronic device for controlling the state of the power sub-module, a DC energy storage capacitor for stabilizing the output voltage, and a bypass switch for bypassing the power sub-module when closed.

[0012] On the other hand, when a power submodule failure occurs in the converter valve, after controlling the bypass switch in the failed power submodule to close, before determining whether the voltage value of the DC energy storage capacitor in the failed power submodule meets the first preset feature, the control method of the converter valve further includes:

[0013] Determine whether the bypass switch in the faulty power submodule fails to close based on the switch state fed back by the bypass switch in the faulty power submodule;

[0014] If the closing fails, a step of determining whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset characteristic is performed;

[0015] If the closure fails, the process ends.

[0016] On the other hand, after judging the switch state feedback of the bypass switch in the faulty power submodule, it is determined that the bypass switch in the faulty power submodule fails to close, and before judging whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset feature, the control method of the converter valve also includes:

[0017] Determine whether the fault type of the faulty power submodule belongs to the first type of fault, wherein the first type of fault refers to: a fault type other than the second type of fault, wherein the second type of fault refers to: a fault that can cause a refusal signal of a bypass switch to be generated;

[0018] If yes, it is determined that the bypass switch of the faulty power submodule is in the open state, and the converter valve is controlled to be locked;

[0019] If not, a step of determining whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset characteristic is performed.

[0020] On the other hand, judging whether the bypass switch in the faulty power submodule fails to close according to the switch state fed back by the bypass switch in the faulty power submodule includes:

[0021] After controlling the bypass switch in the faulty power submodule to be closed for a first preset time period, determining whether the bypass switch in the faulty power submodule is in a closed state;

[0022] If it is not in the closed state, it is determined that the bypass switch in the faulty power submodule fails to close;

[0023] If it is in the closed state, it is determined that the bypass switch in the faulty power submodule is closed successfully.

[0024] On the other hand, after controlling the bypass switch in the faulty power submodule to close for the first preset time, after determining that the bypass switch in the faulty power submodule is not in a closed state, and before determining that the bypass switch in the faulty power submodule fails to close, the control method of the converter valve further includes:

[0025] Determine whether the bypass switch in the faulty power submodule can be switched to a closed state within a second preset time period;

[0026] If not, it is determined that the bypass switch in the faulty power submodule fails to close;

[0027] If so, then it ends.

[0028] On the other hand, the converter valve includes: a converter valve with a modular multi-level converter topology structure.

[0029] On the other hand, the first preset feature includes:

[0030] Whether the voltage of the DC energy storage capacitor can be raised to a preset voltage value within a third preset time period.

[0031] In order to solve the above technical problems, the present invention further provides a control device for a converter valve, comprising:

[0032] A first control module, configured to control the bypass switch in the failed power submodule to close when a power submodule failure occurs in the converter valve;

[0033] A first judgment module is used to judge whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset feature, wherein the first preset feature refers to: the voltage change feature of the DC energy storage capacitor in the power submodule when the bypass switch of the power submodule is in the split state. If it meets the requirement, the second control module is triggered, and if it does not meet the requirement, the first judgment module is triggered;

[0034] A second control module is used to determine that the bypass switch of the faulty power submodule is in an open state and control the converter valve to be locked;

[0035] A first determination module, used to determine whether the bypass switch of the faulty power submodule is in a closed state;

[0036] The converter valve includes a plurality of power sub-modules, and the power sub-modules include: a power electronic device for controlling the state of the power sub-module, a DC energy storage capacitor for stabilizing the output voltage, and a bypass switch for bypassing the power sub-module when closed.

[0037] In order to solve the above technical problems, the present invention further provides a control device for a converter valve, comprising:

[0038] Memory for storing computer programs;

[0039] A processor is used to implement the steps of the control method of the converter valve as described above when executing the computer program.

[0040] In order to solve the above technical problems, the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the control method of the converter valve as described above are implemented.

[0041] Beneficial effect: The present invention provides a control method for a converter valve. Taking into account that (1) the closing control of the bypass switch may fail and (2) the voltage change of the DC energy storage capacitor in the power sub-module can more accurately reflect whether the bypass is successful or not, the present invention can set a first preset feature (the voltage change feature of the DC energy storage capacitor in the power sub-module when the bypass switch of the power sub-module is in the open state). After a power sub-module failure occurs and the bypass switch therein is controlled to be closed, if the voltage value of the DC energy storage capacitor in the failed power sub-module meets the first preset feature, it can be determined that the bypass switch is in the open state (that is, the bypass fails), thereby controlling the converter valve to be locked. If it does not meet the requirement, it can be determined that the bypass switch is in the closed state (that is, the bypass is successful). Since the bypass switch state can be accurately determined, it is possible to avoid controlling the entire converter valve to be locked when the "bypass switch is successfully closed", thereby improving the working efficiency of the converter valve.

[0042] The present invention also provides a control device, equipment and computer-readable storage medium for a converter valve, which have the same beneficial effects as the control method for the converter valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the relevant technologies and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 A schematic flow chart of a control method for a converter valve provided by the present invention;

[0045] Figure 2 A schematic diagram of the structure of a power submodule in a converter valve provided by the present invention;

[0046] Figure 3 A schematic diagram of the structure of a converter valve provided by the present invention;

[0047] Figure 4 A schematic flow chart of another control method for a converter valve provided by the present invention;

[0048] Figure 5 A schematic structural diagram of a control device for a converter valve provided by the present invention;

[0049] Figure 6 A schematic structural diagram of a control device for a converter valve provided by the present invention. DETAILED DESCRIPTION

[0050] The core of the present invention is to provide a control method, device, equipment and computer-readable storage medium for a converter valve. After a power sub-module fails and the bypass switch therein is controlled to be closed, when the voltage value of the DC energy storage capacitor in the failed power sub-module does not meet the first preset feature, it can be determined that the bypass switch is in a closed state (that is, the bypass is successful), and when it meets the first preset feature, it can be determined that the bypass switch is in an open state (that is, the bypass fails), thereby controlling the converter valve to be locked. Since the bypass switch state can be accurately determined, it is possible to avoid controlling the entire converter valve to be locked when the "bypass switch is successfully closed", thereby improving the working efficiency of the converter valve.

[0051] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0052] Please refer to Figure 1 , Figure 1 A flow chart of a control method of a converter valve provided by the present invention is provided, and the control method of the converter valve includes:

[0053] S101: When a power submodule failure occurs in a converter valve, a bypass switch in the failed power submodule is controlled to be closed;

[0054] Specifically, the converter valve can usually be composed of multiple identical power sub-modules, and each power sub-module can perform commutation work. Therefore, even if a small number of power sub-modules stop working, it will not affect the normal operation of the converter valve, provided that the faulty power sub-module needs to be bypassed (short-circuited), and the bypass control of the power sub-module can be performed through the bypass switch inside the power sub-module. Therefore, in this step, when a power sub-module failure occurs in the converter valve, the bypass switch in the faulty power sub-module can be controlled to be closed, that is, an attempt can be made to bypass the faulty power sub-module.

[0055] Among them, some types of faults occurring in the power submodule can be detected and reported.

[0056] S102: Determine whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets a first preset characteristic, wherein the first preset characteristic refers to: a voltage change characteristic of the DC energy storage capacitor in the power submodule when the bypass switch of the power submodule is in a split state;

[0057] Specifically, considering that the closing control of the bypass switch of the power sub-module may not be normally implemented due to various reasons (such as a failure of the bypass switch itself), and the "normal closure or not" of the bypass switch is a hallmark feature of "bypassing the faulty power sub-module", only when the bypass switch is closed normally can the converter valve be controlled to continue working. Therefore, in order to accurately judge whether the bypass switch of the power sub-module is closed, considering that the DC energy storage capacitor inside the converter valve will exhibit specific characteristics when in the "bypass switch split state", a first preset feature is pre-set in the embodiment of the present invention, and after controlling the bypass switch to close, it can be judged whether the voltage value of the DC energy storage capacitor in the faulty power sub-module meets the first preset feature, so as to trigger subsequent judgment actions through the judgment result.

[0058] Among them, the voltage detection of the DC energy storage capacitor can be performed by setting up a corresponding voltage detection circuit. In particular, considering that certain fault types of the power sub-module cause "the original capacitor voltage detection function of the power sub-module to fail", a redundant voltage detection circuit can be additionally set to detect the voltage value of the DC energy storage capacitor. The specific type of the voltage detection circuit is not limited in the present invention.

[0059] S103: If the conditions are met, it is determined that the bypass switch of the faulty power submodule is in an open state, and the converter valve is controlled to be locked;

[0060] Specifically, since the first preset characteristic refers to: the voltage change characteristic of the DC energy storage capacitor in the power sub-module when the bypass switch of the power sub-module is in the split state, when the voltage value of the DC energy storage capacitor meets the first preset characteristic, it can be determined that the bypass switch of the faulty power sub-module is in the split state. In this case, since the bypass switch fails to close successfully, the faulty power sub-module cannot be bypassed successfully, and the converter valve cannot be supported to continue working, so the converter valve can be controlled to be locked.

[0061] In addition, when it is determined that the bypass switch fails to close successfully, a prompt or alarm may be given for "the bypass switch fails to close successfully" so that the staff can perform timely maintenance.

[0062] S104: If not, determining that the bypass switch of the faulty power submodule is in a closed state;

[0063] The converter valve includes a plurality of power sub-modules, and the power sub-modules include: power electronic devices for controlling the state of the power sub-modules, DC energy storage capacitors for stabilizing the output voltage, and bypass switches for bypassing the power sub-modules when closed.

[0064] Specifically, since the first preset characteristic refers to: the voltage change characteristic of the DC energy storage capacitor in the power sub-module when the bypass switch of the power sub-module is in the open state, when the voltage value of the DC energy storage capacitor does not meet the first preset characteristic, it can be determined that the bypass switch of the faulty power sub-module is in the closed state (or not in the open state).

[0065] In order to better illustrate the embodiments of the present invention, please refer to Figure 2 and Figure 3 , Figure 2 A schematic diagram of the structure of a power submodule in a converter valve provided by the present invention. Figure 3 A schematic diagram of the structure of a converter valve provided by the present invention, Figure 2 K1 is the bypass switch, C0 is the DC energy storage capacitor, u c is the voltage value of the DC energy storage capacitor, and the first diode D1, the second diode D2, the thyristor K2, the first power switch T1 and the second power switch T2 can be regarded as bidirectional controllable power electronic devices of the power submodule; Figure 3 The converter valve in the embodiment includes three phase units, each phase unit includes two bridge arm units (i.e., upper bridge arm and lower bridge arm), and each bridge arm unit includes several power sub-modules SM1 to SM N .

[0066] The present invention provides a control method for a converter valve. Considering that (1) the closing control of the bypass switch may fail and (2) the voltage change of the DC energy storage capacitor in the power submodule can more accurately reflect whether the bypass is successful or not, the present invention can set a first preset feature (the voltage change feature of the DC energy storage capacitor in the power submodule when the bypass switch of the power submodule is in the open position state). After a power submodule failure occurs and the bypass switch therein is controlled to be closed, if the voltage value of the DC energy storage capacitor in the failed power submodule meets the first preset feature, it can be determined that the bypass switch is in the open position state (that is, the bypass fails), thereby controlling the converter valve to be locked. If it does not meet the first preset feature, it can be determined that the bypass switch is in the closed position state (that is, the bypass is successful). Since the bypass switch state can be accurately determined, it can be avoided to control the entire converter valve to be locked when the "bypass switch is successfully closed", thereby improving the working efficiency of the converter valve.

[0067] Based on the above embodiments:

[0068] As an optional embodiment, when a power submodule failure occurs in the converter valve, after controlling the bypass switch in the failed power submodule to close, and before determining whether the voltage value of the DC energy storage capacitor in the failed power submodule meets the first preset feature, the control method of the converter valve also includes:

[0069] Determine whether the bypass switch in the faulty power submodule fails to close based on the switch state fed back by the bypass switch in the faulty power submodule;

[0070] If the closing fails, a step of determining whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset characteristic is performed;

[0071] If the closure fails, the process ends.

[0072] Specifically, considering that the bypass switch in the power sub-module itself may have a state feedback function, if the bypass switch can feedback normally, the closed state can be fed back to the controller, and if the bypass switch cannot feedback normally, the closed state fed back by it cannot be received, but this does not mean that "the bypass switch must not be closed normally", so in the embodiment of the present invention, only "the closed state fed back by the bypass switch" is adopted here, that is, the embodiment of the present invention can judge whether the bypass switch in the faulty power sub-module fails to close through the switch state fed back by the bypass switch in the faulty power sub-module. If it does not fail to close, it means that the bypass switch is closed successfully and can support the converter valve to continue working, so it can be ended. In the case of closing failure, it means that the state of the bypass switch needs to be further determined by the voltage value of the DC energy storage capacitor.

[0073] The state feedback function of the bypass switch may be implemented in a variety of ways, such as through a feedback contact, etc., which is not limited in the embodiment of the present invention.

[0074] As an optional embodiment, after judging the switch state feedback of the bypass switch in the faulty power submodule, it is determined that the bypass switch in the faulty power submodule fails to close, and before judging whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset feature, the control method of the converter valve also includes:

[0075] Determine whether the fault type of the faulty power submodule belongs to the first type of fault, wherein the first type of fault refers to: a fault type other than the second type of fault, and the second type of fault refers to: a fault that can cause a refusal signal of the bypass switch to be generated;

[0076] If yes, it is determined that the bypass switch of the faulty power submodule is in the open state, and the converter valve is controlled to be locked;

[0077] If not, a step of determining whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset characteristic is performed.

[0078] Specifically, considering that the power sub-module itself can report some types of faults of itself, including the first type of faults and the second type of faults, and when the fault does not belong to the second type of fault, it means that the "switch state fed back by the bypass switch in the faulty power sub-module" is accurate at this time, so there is no need to perform subsequent judgment. Therefore, in the embodiment of the present invention, it can be judged whether the fault type of the faulty power sub-module belongs to the first type of fault, wherein the first type of fault refers to: a fault type other than the second type of fault, and the second type of fault refers to: a fault that can cause a refusal signal of the bypass switch to be generated. If it belongs to the first type of fault, it can be determined that the bypass switch of the faulty power sub-module is in a split state (that is, the bypass switch does refuse to move). At this time, since the faulty power sub-module cannot be bypassed, the converter valve can be controlled to be locked. If it does not belong to the first type of fault, it means that the refusal signal fed back by the bypass switch at this time is not credible, so it is necessary to continue to execute the step of determining whether the voltage value of the DC energy storage capacitor in the faulty power sub-module meets the first preset feature.

[0079] Among them, the refusal signal refers to that after the first preset time period for controlling the bypass switch to close, if the bypass switch does not feedback the closed state, it means that the bypass switch generates a "refusal signal". The fault types included in the second type of fault can be set independently, such as the feedback contact failure of the bypass switch and the communication failure between the bypass switch and the controller, etc., which are not limited in the embodiments of the present invention.

[0080] As an optional embodiment, judging whether the bypass switch in the faulty power submodule fails to close according to the switch state fed back by the bypass switch in the faulty power submodule includes:

[0081] After controlling the bypass switch in the faulty power submodule to be closed for a first preset time period, determining whether the bypass switch in the faulty power submodule is in a closed state;

[0082] If it is not in the closed state, it is determined that the bypass switch in the faulty power submodule fails to close;

[0083] If it is in the closed state, it is determined that the bypass switch in the faulty power submodule is closed successfully.

[0084] Specifically, considering that both the "response of the bypass switch to the control action" and the "state feedback of the bypass switch" require time, the embodiments of the present invention can determine whether the bypass switch in the faulty power sub-module is in the closed state after controlling the first preset time length of the bypass switch in the faulty power sub-module to close. If it is not in the closed state, it is determined that the bypass switch in the faulty power sub-module has failed to close (equivalent to generating a refusal signal); if it is in the closed state, it is determined that the bypass switch in the faulty power sub-module has closed successfully, thereby being able to efficiently "determine whether the bypass switch in the faulty power sub-module has failed to close through the switch state fed back by the bypass switch in the faulty power sub-module."

[0085] As an optional embodiment, after controlling the bypass switch in the faulty power submodule to close for a first preset time, after determining that the bypass switch in the faulty power submodule is not in a closed state, and before determining that the bypass switch in the faulty power submodule fails to close, the control method of the converter valve further includes:

[0086] Determine whether the bypass switch in the faulty power submodule can be switched to a closed state within a second preset time period;

[0087] If not, it is determined that the bypass switch in the faulty power submodule fails to close;

[0088] If so, then it ends.

[0089] Specifically, considering that the state feedback signal of the bypass switch may not be true and persistent due to reasons such as signal jitter, in order to ensure that the true state of the bypass switch feedback is collected, in an embodiment of the present invention, after determining that the bypass switch in the faulty power sub-module is not in the closed state, it can be determined whether the bypass switch in the faulty power sub-module can jump to the closed state within a second preset time length. If not, it means that the switch state fed back by the bypass switch has been stable and true, so it can be determined that the bypass switch in the faulty power sub-module has failed to close.

[0090] To better illustrate the embodiments of the present invention, please refer to Figure 4 , Figure 4 FIG. 1 is a flow chart of another control method of a converter valve provided by the present invention. After the process starts, the power submodule fault can be first determined, and then the bypass switch in the faulty power submodule is controlled to be closed (this action belongs to the original action of the control system and is therefore not included in the control method). Figure 4 ), after T1 (i.e., the first preset time length), it is determined whether a refusal signal is received (i.e., whether the bypass switch does not feedback the closed state). If not received, it means that the bypass switch is closed successfully (i.e., the bypass is successful), and the converter valve can operate normally. If a refusal signal is received, it can be determined whether the refusal signal lasts for T2 time (the second preset time length). If it does not last for T2 time, it is determined that the bypass is successful and the converter valve can operate normally. If it lasts for T2 time, it means that "the bypass switch is indeed determined to be refused by the state feedback function of the bypass switch". At this time, it is necessary to further determine whether the fault belongs to the first type of fault. If it does, it can be determined that the bypass switch refuses to move, and the converter valve is requested to be locked. If it does not, it can be further determined (whether the voltage of the DC energy storage capacitor in the power sub-module meets the first preset feature). If it does not meet, it can be determined that the bypass is successful and the converter valve can operate normally. If it meets, it can be determined that the bypass switch refuses to move, and the converter valve is requested to be locked.

[0091] As an optional embodiment, the converter valve includes: a converter valve with a modular multi-level converter topology structure.

[0092] Specifically, a converter valve with an MMC (Modular Multilevel Converter) topology structure can be applied to a flexible DC converter station of a flexible DC power grid. It can be a half-bridge type or a full-bridge type, etc., which is not limited in the embodiments of the present invention.

[0093] Of course, in addition to this specific type, the converter valve may also be of many other types, which is not limited in the embodiment of the present invention.

[0094] As an optional embodiment, the first preset feature includes:

[0095] Whether the voltage of the DC energy storage capacitor can be raised to a preset voltage value within a third preset time period.

[0096] Specifically, considering that when the bypass switch is in the split state, the voltage value of the DC energy storage capacitor will rise, which means that within a certain period of time, the voltage value of the DC energy storage capacitor will basically rise by a certain amplitude. Therefore, by "whether the voltage of the DC energy storage capacitor can rise to the preset voltage value within the third preset time length", it can be determined that the DC energy storage capacitor is indeed in the split state. Therefore, the first preset feature in the embodiment of the present invention may include whether the voltage of the DC energy storage capacitor can rise to the preset voltage value within the third preset time length.

[0097] Of course, in addition to this form, the first preset feature can also be of many other types, which is not limited in the embodiment of the present invention.

[0098] Among them, the first preset time length to the third preset time length and the preset voltage value can all be set independently, and the embodiment of the present invention is not limited here.

[0099] Please refer to Figure 5 , Figure 5 A schematic diagram of the structure of a control device for a converter valve provided by the present invention, the control device for the converter valve comprises:

[0100] The first control module 51 is used to control the bypass switch in the faulty power submodule to close when a power submodule fault occurs in the converter valve;

[0101] The first judgment module 52 is used to judge whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset feature, wherein the first preset feature refers to: the voltage change feature of the DC energy storage capacitor in the power submodule when the bypass switch of the power submodule is in the split state. If it meets the requirement, the second control module is triggered, and if it does not meet the requirement, the first judgment module is triggered;

[0102] The second control module 53 is used to determine whether the bypass switch of the faulty power submodule is in an open state and control the converter valve to be locked;

[0103] A first determination module 54, used to determine whether the bypass switch of the faulty power submodule is in a closed state;

[0104] The converter valve includes a plurality of power sub-modules, and the power sub-modules include: power electronic devices for controlling the state of the power sub-modules, DC energy storage capacitors for stabilizing the output voltage, and bypass switches for bypassing the power sub-modules when closed.

[0105] For an introduction to the control device of the converter valve provided in the embodiment of the present invention, please refer to the embodiment of the control method of the converter valve described above, and the embodiment of the present invention will not be described in detail here.

[0106] Please refer to Figure 6 , Figure 6A schematic diagram of the structure of a control device for a converter valve provided by the present invention, the control device for the converter valve comprises:

[0107] A memory 61, used for storing computer programs;

[0108] The processor 62 is used to implement the steps of the control method of the converter valve in the above-mentioned embodiment when executing the computer program.

[0109] For an introduction to the control device of the converter valve provided in the embodiment of the present invention, please refer to the embodiment of the control method of the converter valve described above, and the embodiment of the present invention will not be described in detail here.

[0110] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the control method of the above-mentioned converter valve are implemented.

[0111] For an introduction to the computer-readable storage medium provided in an embodiment of the present invention, please refer to the aforementioned embodiment of the control method of the converter valve, and the embodiment of the present invention will not be described in detail here.

[0112] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. It should also be noted that in this specification, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements that are not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or equipment including the element.

[0113] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for a converter valve, characterized in that: include: When a power submodule failure occurs in the converter valve, the bypass switch in the failed power submodule is controlled to be closed; Determine whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset feature, wherein the first preset feature refers to: the voltage change feature of the DC energy storage capacitor in the power submodule when the bypass switch of the power submodule is in the open position state; If it is met, it is determined that the bypass switch of the faulty power submodule is in the open state, and the converter valve is controlled to be locked; If not, it is determined that the bypass switch of the faulty power submodule is in the closed state; The converter valve includes a plurality of power sub-modules, and the power sub-modules include: a power electronic device for controlling the state of the power sub-module, a DC energy storage capacitor for stabilizing the output voltage, and a bypass switch for bypassing the power sub-module when closed.

2. The control method of the converter valve according to claim 1, characterized in that: When a power submodule failure occurs in the converter valve, after controlling the bypass switch in the failed power submodule to close, and before determining whether the voltage value of the DC energy storage capacitor in the failed power submodule meets the first preset feature, the control method of the converter valve further includes: Determine whether the bypass switch in the faulty power submodule fails to close based on the switch state fed back by the bypass switch in the faulty power submodule; If the closing fails, a step of determining whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset characteristic is performed; If the closure fails, the process ends.

3. The control method of the converter valve according to claim 2, characterized in that: After judging the switch state feedback of the bypass switch in the faulty power submodule, it is determined that the bypass switch in the faulty power submodule fails to close, and before judging whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset feature, the control method of the converter valve also includes: Determine whether the fault type of the faulty power submodule belongs to the first type of fault, wherein the first type of fault refers to: a fault type other than the second type of fault, and the second type of fault refers to: a fault that can cause a refusal signal of the bypass switch to be generated; If yes, it is determined that the bypass switch of the faulty power submodule is in the open state, and the converter valve is controlled to be locked; If not, a step of determining whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset characteristic is performed.

4. The control method of the converter valve according to claim 2, characterized in that: Judging whether the bypass switch in the faulty power submodule fails to close by the switch state fed back by the bypass switch in the faulty power submodule includes: After controlling the bypass switch in the faulty power submodule to be closed for a first preset time period, determining whether the bypass switch in the faulty power submodule is in a closed state; If it is not in the closed state, it is determined that the bypass switch in the faulty power submodule fails to close; If it is in the closed state, it is determined that the bypass switch in the faulty power submodule is closed successfully.

5. The control method of the converter valve according to claim 4, characterized in that: After controlling the bypass switch in the faulty power submodule to close for a first preset time, after determining that the bypass switch in the faulty power submodule is not in a closed state, and before determining that the bypass switch in the faulty power submodule fails to close, the control method of the converter valve further includes: Determine whether the bypass switch in the faulty power submodule can be switched to a closed state within a second preset time period; If not, it is determined that the bypass switch in the faulty power submodule fails to close; If so, then it ends.

6. The control method of the converter valve according to claim 1, characterized in that: The converter valve comprises: a converter valve with a modular multi-level converter topology structure.

7. The control method of a converter valve according to any one of claims 1 to 6, characterized in that: The first preset feature includes: Whether the voltage of the DC energy storage capacitor can be raised to a preset voltage value within a third preset time period.

8. A control device for a converter valve, characterized in that: include: A first control module, configured to control the bypass switch in the failed power submodule to close when a power submodule failure occurs in the converter valve; A first judgment module is used to judge whether the voltage value of the DC energy storage capacitor in the faulty power submodule meets the first preset feature, wherein the first preset feature refers to: the voltage change feature of the DC energy storage capacitor in the power submodule when the bypass switch of the power submodule is in the split state. If it meets the requirement, the second control module is triggered, and if it does not meet the requirement, the first judgment module is triggered; A second control module is used to determine that the bypass switch of the faulty power submodule is in an open state and control the converter valve to be locked; A first determination module, used to determine whether the bypass switch of the faulty power submodule is in a closed state; The converter valve includes a plurality of power sub-modules, and the power sub-modules include: a power electronic device for controlling the state of the power sub-module, a DC energy storage capacitor for stabilizing the output voltage, and a bypass switch for bypassing the power sub-module when closed.

9. A control device for a converter valve, characterized in that: include: Memory for storing computer programs; A processor, configured to implement the steps of the control method of the converter valve according to any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the control method of the converter valve according to any one of claims 1 to 7 are implemented.

Images