Converter valve power module fault type identification method and device

Abstract

The invention relates to the technical field of direct current converter valves, in particular to a converter valve power module fault type identification method and device. The method comprises the following steps: acquiring a first target parameter, a second target parameter, a third target parameter, a bypass switch state, an issuing state of a bypass switch conduction instruction, and an issuing state of a conduction instruction of a target IGBT device; according to a comparison result of the first target parameter and a preset first parameter threshold value, a comparison result of the second target parameter and a preset second parameter threshold value, a bypass switch state and an issuing state of a bypass switch conduction instruction; according to a comparison result of the third target parameter and a preset third parameter threshold value, an issuing state of a conduction instruction of the target IGBT device, a comparison result of the third target parameter and a preset fourth parameter threshold value, and an issuing state of the conduction instruction of the target IGBT device, a fault type is identified; the existing fault identification method has the technical problems of long time consumption and low efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of direct current converter valves, and in particular to a method and device for identifying a fault type of a converter valve power module. Background Art

[0002] The converter valve power module (referred to as power module) is a device used for power conversion, which can convert AC into DC, or convert DC into AC. In the flexible DC transmission system, the control system can send control signals to the gate drive circuit of the converter valve power module according to the power conversion requirements, and the IGBT devices inside the converter valve power module are turned on and off in a certain order and time interval to achieve power conversion.

[0003] During operation, when the converter valve power module in the flexible DC transmission system is unlocked, it will be in the "engaged state". At this time, if a DC capacitor direct fault occurs in the converter valve power module, the power module control board in the system can only determine that a direct fault has occurred in the DC capacitor, and send the "IGBT direct fault" to the upper valve control system. It cannot accurately identify which specific component failure in the power module caused the direct fault. The existing technology can only wait until the transmission project is locked and shut down, remove the direct fault power module from the valve tower, and return it to the manufacturer. After the manufacturer disassembles and analyzes it, it can determine which component failure inside the power module caused the direct fault in the power module. However, this processing method results in too long time to determine the cause of the fault, and the efficiency of accident cause investigation is low. Summary of the invention

[0004] The present invention provides a method and device for identifying the fault type of a converter valve power module, which are used to solve the technical problems that the existing fault identification methods take a long time and have low efficiency.

[0005] On one hand, the present invention provides a method for identifying the fault type of a converter valve power module, wherein the power module includes a bypass thyristor, a bypass switch, and an IGBT component; the IGBT component includes a target IGBT device; when the power module is in an on-state and a through fault exists, the method includes:

[0006] Obtaining a first target parameter, a second target parameter, a third target parameter, a bypass switch state, a state of issuing a bypass switch on instruction, and a state of issuing a target IGBT device on instruction;

[0007] According to the comparison result of the first target parameter and the preset first parameter threshold, judging whether the bypass thyristor has a low-voltage breakdown fault, and if so, judging that the fault type is a bypass thyristor low-voltage breakdown;

[0008] According to the comparison result of the second target parameter and the preset second parameter threshold, the bypass switch state and the issuing state of the bypass switch conduction instruction, it is judged whether there is gap discharge of the bypass switch, and if so, it is determined that the fault type is gap discharge of the bypass switch;

[0009] According to the comparison result of the third target parameter and the preset third parameter threshold value and the issuing state of the target IGBT device conduction instruction, it is judged whether the target IGBT device has a false triggering fault, and if so, it is determined that the fault type is a false triggering of the IGBT device;

[0010] According to the comparison result of the third target parameter and the preset fourth parameter threshold value and the issuing status of the target IGBT device conduction instruction, it is judged whether the target IGBT device has a short circuit failure fault. If so, the fault type is determined to be an IGBT device short circuit failure fault.

[0011] Optionally, the first target parameter includes a current and a first duration of a bypass thyristor, a first inter-electrode voltage and a second duration of a target IGBT device; the first parameter threshold includes a first voltage threshold, a first current threshold, a first time threshold and a second time threshold;

[0012] The step of judging whether a low-voltage breakdown fault occurs in the bypass thyristor according to a comparison result between the first target parameter and a preset first parameter threshold value includes:

[0013] When the first inter-electrode voltage is less than the first voltage threshold and the second duration exceeds a first time threshold, and the current of the bypass thyristor is greater than the first current threshold and the first duration exceeds a second time threshold, it is determined that a low-voltage breakdown fault occurs in the bypass thyristor.

[0014] Optionally, the second target parameter includes a first inter-electrode voltage and a second duration of the target IGBT device, a current and a third duration of the bypass switch; the second parameter threshold includes the first voltage threshold, the first time threshold, the second current threshold and the third time threshold;

[0015] The step of judging whether there is gap discharge in the bypass switch according to the comparison result of the second target parameter and the preset second parameter threshold, the bypass switch state and the issuing state of the bypass switch conduction instruction includes:

[0016] When the first inter-pole voltage is less than the first voltage threshold and the first duration exceeds the first time threshold, and the current of the bypass switch is greater than the second current threshold and the third duration exceeds the third time threshold, and the issuance status of the bypass switch conduction instruction is not issued, and the bypass switch state is in the open state, it is determined that the bypass switch has gap discharge.

[0017] Optionally, the third target parameter includes: a first inter-electrode voltage and a second duration of a target IGBT device, a current and a fourth duration of a target IGBT device, a second inter-electrode voltage and a fifth duration of a target IGBT device; the third parameter threshold includes: the first voltage threshold, the first time threshold, the third current threshold, the fourth time threshold, the target on-voltage, and the fifth time threshold;

[0018] The step of judging whether the target IGBT device has a false triggering fault according to a comparison result of the third target parameter and a preset third parameter threshold value and a status of issuing a turn-on instruction of the target IGBT device comprises:

[0019] When the first inter-pole voltage is less than the first voltage threshold and the first duration exceeds the first time threshold, and the current of the target IGBT device is greater than the third current threshold and the fourth duration exceeds the fourth time threshold, and the sending status of the target IGBT device turn-on instruction is not sent, and the second inter-pole voltage is greater than the target turn-on voltage and the fifth duration is greater than the fifth time threshold, it is determined that the target IGBT device has a false triggering fault.

[0020] Optionally, the fourth parameter threshold includes the first voltage threshold, the first time threshold, the third current threshold, the fourth time threshold, the target on-voltage, and a sixth time threshold;

[0021] The step of judging whether the target IGBT device has a short-circuit failure fault according to the comparison result of the third target parameter and the preset fourth parameter threshold value and the issuing state of the target IGBT device conduction instruction comprises:

[0022] When the first inter-pole voltage is less than the first voltage threshold and the first duration exceeds the first time threshold, and the current of the target IGBT device is greater than the third current threshold and the fourth duration exceeds the fourth time threshold, and the sending status of the target IGBT device turn-on instruction is not sent, and the second inter-pole voltage is less than the target turn-on voltage and the fifth duration is greater than the fifth time threshold, it is determined that the target IGBT device has a short-circuit failure fault.

[0023] Optionally, when the power module is a full-bridge power module, the first target parameter includes the current and the first duration, the first inter-electrode voltage difference, the second inter-electrode voltage difference, and the sixth duration of the bypass thyristor; the first parameter threshold includes a first voltage threshold, a first current threshold, a first time threshold, and a second time threshold;

[0024] The step of judging whether a low-voltage breakdown fault occurs in the bypass thyristor according to a comparison result between the first target parameter and a preset first parameter threshold value includes:

[0025] When the first inter-electrode voltage difference and the second inter-electrode voltage difference are both smaller than the first voltage threshold and the sixth duration exceeds the first time threshold, and the current of the bypass thyristor is greater than the first current threshold and the first duration exceeds the second time threshold, it is determined that a low-voltage breakdown fault occurs in the bypass thyristor.

[0026] Optionally, the second target parameter includes the current and the third duration of the bypass switch, the first inter-electrode voltage difference, the second inter-electrode voltage difference, and the sixth duration; the second parameter threshold includes the first voltage threshold, the first time threshold, the second current threshold, and the third time threshold;

[0027] The step of judging whether there is gap discharge in the bypass switch according to the comparison result of the second target parameter and the preset second parameter threshold, the bypass switch state and the issuing state of the bypass switch conduction instruction includes:

[0028] When the first inter-pole voltage difference and the second inter-pole voltage difference are both smaller than the first voltage threshold and the sixth duration exceeds the first time threshold, and the current of the bypass switch is greater than the second current threshold and the third duration exceeds the third time threshold, and the issuance status of the bypass switch conduction instruction is not issued, and the bypass switch state is in the open state, it is determined that there is gap discharge in the bypass switch.

[0029] Optionally, when the power module is a half-bridge power module, the target IGBT device is an IGBT device in a cut-off state in the half-bridge power module in an on state.

[0030] Optionally, when the power module is a full-bridge power module, the target IGBT device includes any one of two IGBT devices in an off state in the full-bridge power module in an on state.

[0031] Another aspect of the present invention further provides a device for identifying a fault type of a converter valve power module, the device comprising a processor and a memory;

[0032] The memory is used to store program code and transmit the program code to the processor;

[0033] The processor is configured to execute any of the above methods according to instructions in the program code.

[0034] It can be seen from the above technical solutions that the present invention has the following advantages:

[0035] The present invention provides a method for identifying the fault type of a converter valve power module, wherein the power module comprises a bypass thyristor, a bypass switch, and an IGBT component; the IGBT component comprises a target IGBT device; when the power module is in an on-state and a through fault exists, the method comprises: obtaining a first target parameter, a second target parameter, a third target parameter, a bypass switch state, a state of issuing a bypass switch on instruction, and a state of issuing a target IGBT device on instruction; judging whether a low-voltage breakdown fault occurs in the bypass thyristor according to a comparison result between the first target parameter and a preset first parameter threshold, and if so, judging that the fault type is a bypass thyristor low-voltage breakdown; judging whether a low-voltage breakdown fault occurs in the bypass thyristor according to a comparison result between the second target parameter and a preset second parameter threshold According to the comparison result of the third target parameter and the preset third parameter threshold value and the issuing status of the on-instruction of the target IGBT device, it is judged whether there is a false triggering fault in the target IGBT device. If so, the fault type is judged to be a false triggering of the IGBT device; according to the comparison result of the third target parameter and the preset fourth parameter threshold value and the issuing status of the on-instruction of the target IGBT device, it is judged whether there is a short-circuit failure fault in the target IGBT device. If so, the fault type is judged to be a short-circuit failure fault of the IGBT device.

[0036] In the present invention, by acquiring the first target parameter, the second target parameter, the third target parameter, the bypass switch state, the issuing state of the bypass switch on-instruction, and the issuing state of the target IGBT device on-instruction, and based on the comparison result of the first target parameter and the preset first parameter threshold, it is determined whether the bypass thyristor has a low-voltage breakdown fault. If so, it is determined that the fault type is the bypass thyristor low-voltage breakdown, thereby realizing the identification of the bypass thyristor low-voltage breakdown; and based on the comparison result of the second target parameter and the preset second parameter threshold, the bypass switch state and the issuing state of the bypass switch on-instruction, it is determined whether the bypass switch has gap discharge. If so, it is determined that the fault type is the bypass switch gap discharge. , realizing the identification of the fault of bypass switch gap discharge; and judging whether the target IGBT device has a false trigger fault according to the comparison result of the third target parameter and the preset third parameter threshold value and the issuing state of the target IGBT device conduction instruction, if so, judging the fault type as IGBT device false trigger, realizing the identification of the fault of IGBT device false trigger; and judging whether the target IGBT device has a short circuit failure fault according to the comparison result of the third target parameter and the preset fourth parameter threshold value and the issuing state of the target IGBT device conduction instruction, if so, judging the fault type as IGBT device short circuit failure fault, realizing the identification of IGBT device short circuit failure fault. It can be seen from the above that when the power module is in the input state and there is a through fault, the faulty component and fault type can be quickly and accurately identified by adopting the identification method provided by the present invention, without disassembling the power module, solving the technical problems of the existing fault identification method taking a long time and low efficiency, achieving the technical effect of reducing the troubleshooting time and improving the troubleshooting efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be 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 paying creative labor.

[0038] Figure 1 A flow chart of a method for identifying a fault type of a converter valve power module provided in Embodiment 1 of the present invention;

[0039] Figure 2 A schematic diagram of the structure of a half-bridge power module provided in Embodiment 2 of the present invention;

[0040] Figure 3 A flow chart of a method for identifying a fault type of a converter valve power module provided in Embodiment 2 of the present invention;

[0041] Figure 4 A schematic diagram of the structure of a full-bridge power module provided in Embodiment 3 of the present invention;

[0042] Figure 5 A flow chart of a method for identifying a fault type of a converter valve power module provided in Embodiment 3 of the present invention. DETAILED DESCRIPTION

[0043] The embodiment of the present invention provides a method and device for identifying the fault type of a converter valve power module, which are used to solve the technical problem that the existing fault identification method takes a long time and has low efficiency.

[0044] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the drawings in the embodiments of the present invention. Obviously, the embodiments described below 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 creative work are within the scope of protection of the present invention.

[0045] Embodiment 1:

[0046] See also Figure 1 The embodiment of the present invention provides a method for identifying the fault type of a converter valve power module, wherein the power module includes a bypass thyristor, a bypass switch, and an IGBT component; the IGBT component includes a target IGBT device; when the power module is in an on-state and a through fault exists, the method includes:

[0047] 101. Obtain a first target parameter, a second target parameter, a third target parameter, a bypass switch state, a state of issuing a bypass switch on instruction, and a state of issuing a target IGBT device on instruction.

[0048] It should be noted that the first target parameter, the second target parameter, and the third target parameter can be collected from the power module. Among them, the first target parameter is used to identify the bypass thyristor low-voltage breakdown, the second target parameter is used to identify the bypass switch gap discharge fault, and the third target parameter is used to identify the IGBT device mis-triggering and IGBT device short-circuit failure fault. The bypass switch state includes the closed state and the open state, and the sending state of the target IGBT device conduction instruction includes not sent and sent.

[0049] 102. According to a comparison result between the first target parameter and a preset first parameter threshold, determine whether a low-voltage breakdown fault occurs in the bypass thyristor; if so, determine that the fault type is a low-voltage breakdown of the bypass thyristor.

[0050] It should be noted that the low-voltage breakdown of the bypass thyristor refers to a fault phenomenon in which the PN junction of the thyristor undergoes reverse breakdown under a voltage lower than the normal rated voltage of the bypass thyristor, causing it to lose its unidirectional conductivity and controllability.

[0051] 103. According to the comparison result between the second target parameter and the preset second parameter threshold, the bypass switch state and the issuing state of the bypass switch conduction instruction, determine whether there is gap discharge in the bypass switch; if so, determine that the fault type is gap discharge of the bypass switch.

[0052] It should be noted that the bypass switch gap discharge refers to a fault condition in which an unexpected discharge phenomenon occurs in the gap between electrodes of the bypass switch, thereby causing the bypass switch to fail to work normally or to degrade in performance.

[0053] 104. According to the comparison result between the third target parameter and the preset third parameter threshold value and the issuing status of the target IGBT device conduction instruction, determine whether the target IGBT device has a false triggering fault; if so, determine that the fault type is a false triggering of the IGBT device.

[0054] It should be noted that the false triggering of IGBT devices, whose full name is false triggering of IGBT devices due to interference, means that the IGBT device enters the conducting state due to interference when it should not be conducting.

[0055] 105. According to the comparison result between the third target parameter and the preset fourth parameter threshold value and the issuing status of the target IGBT device conduction instruction, determine whether the target IGBT device has a short circuit failure fault. If so, determine that the fault type is an IGBT device short circuit failure fault.

[0056] It should be noted that the short-circuit failure of IGBT devices is called short-circuit failure at rated voltage of IGBT devices. It means that when the voltage borne by the IGBT device is its rated voltage, due to a short-circuit failure, the device loses its normal function and cannot continue to work effectively.

[0057] It is understandable that there is no sequential order between step 102 and step 105, and they may be executed simultaneously or in a desired order as required. The specific value of each parameter threshold may be set according to actual conditions.

[0058] In this embodiment, by obtaining the first target parameter, the second target parameter, the third target parameter, the bypass switch state, the issuance state of the bypass switch turn-on instruction, and the issuance state of the target IGBT device turn-on instruction, and based on the comparison result of the first target parameter and the preset first parameter threshold, it is determined whether the bypass thyristor has a low-voltage breakdown fault. If so, the fault type is determined to be the bypass thyristor low-voltage breakdown, thereby realizing the identification of the bypass thyristor low-voltage breakdown; and based on the comparison result of the second target parameter and the preset second parameter threshold, the bypass switch state and the issuance state of the bypass switch turn-on instruction, it is determined whether the bypass switch has gap discharge. If so, the fault type is determined to be the bypass switch gap discharge , and the fault of bypass switch gap discharge is recognized; and according to the comparison result of the third target parameter and the preset third parameter threshold value, and the issuing state of the target IGBT device conduction instruction, it is judged whether the target IGBT device has a false trigger fault, and if so, the fault type is judged as the IGBT device false trigger, and the fault of IGBT device false trigger is recognized; and according to the comparison result of the third target parameter and the preset fourth parameter threshold value, and the issuing state of the target IGBT device conduction instruction, it is judged whether the target IGBT device has a short circuit failure fault, and if so, the fault type is judged as the IGBT device short circuit failure fault, and the fault of IGBT device short circuit failure is recognized. It can be seen from the above that when the power module is in the input state and there is a through fault, the faulty component and fault type can be quickly and accurately identified by adopting the identification method provided by the present invention, without disassembling the power module, solving the technical problems of the existing power module fault identification method taking a long time and low efficiency, and achieving the technical effect of reducing the troubleshooting time and improving the troubleshooting efficiency.

[0059] Further, the power module type includes a half-bridge power module or a full-bridge power module.

[0060] Embodiment 2:

[0061] When the power module is a half-bridge power module, Figure 2As shown, its structure includes: a bypass thyristor SCR, a bypass switch S, an IGBT component, a first capacitor C1 and a first resistor R1; the IGBT component includes a first IGBT device T1 and a second IGBT device T2; the first IGBT device T1 is also provided with a parasitic diode D1, and the second IGBT device T2 is also provided with a parasitic diode D2; the bypass thyristor SCR, the bypass switch S, and the second IGBT device T2 are sequentially connected in parallel, the first IGBT device T1 and the second IGBT device T2 are connected in series, the first capacitor C1 and the first IGBT device T1 and the second IGBT device T2 are connected in parallel, and the first resistor R1 and the first capacitor C1 are connected in parallel; wherein the bypass thyristor SCR, the bypass switch S, and the second IGBT device T2 are respectively connected in series with the Hall sensors CT1, CT2, and CT3; the Hall sensors CT1, CT2, and CT3 are connected to the power module control board for real-time measurement of the current value I flowing through the bypass thyristor SCR, the bypass switch S, and the second IGBT device T2 SCR ,I S ,I T2 , and sent to the power module control board; the driver board of the second IGBT device T2 is connected to the second IGBT device T2 and the power module control board, and is used to measure the collector-emitter voltage U of the second IGBT device T2 in real time ceT2 , the voltage U between the gate and emitter of the second IGBT device T2 geT2 , and sent to the power module control board in time.

[0062] Among them, the current I SCR ,I S ,I T2 Direction Figure 2 As shown, the direction indicated by the arrow is the positive direction. When the half-bridge power module is in the on-state, the first IGBT device T1 is turned on and the second IGBT device T2 is turned off. If a direct fault occurs in the DC capacitor of the half-bridge power module at this time, the fault type can be identified by the converter valve power module fault type identification method provided by the following embodiment of the present invention, thereby determining the cause of the direct fault of the half-bridge power module. In this embodiment, the target IGBT device is an IGBT device in the off state in the half-bridge power module in the on-state, that is, the target IGBT device in this embodiment is the second IGBT device T2.

[0063] Furthermore, if Figure 3 As shown, a method for identifying a fault type of a converter valve power module provided by an embodiment of the present invention is applied to a power module control board, and the steps specifically include:

[0064] 201. Obtain a first target parameter, a second target parameter, a third target parameter, a bypass switch state, a state of issuing a bypass switch on instruction, and a state of issuing a target IGBT device on instruction.

[0065] It should be noted that the first target parameter includes the current and the first duration of the bypass thyristor, the first inter-electrode voltage and the second duration of the target IGBT device; the first parameter threshold includes the first voltage threshold, the first current threshold, the first time threshold and the second time threshold.

[0066] The second target parameters include a first inter-electrode voltage and a second duration of the target IGBT device, a current and a third duration of the bypass switch; and the second parameter thresholds include a first voltage threshold, a first time threshold, a second current threshold and a third time threshold.

[0067] The third target parameters include: the first inter-electrode voltage and the second duration of the target IGBT device, the current and the fourth duration of the target IGBT device, the second inter-electrode voltage and the fifth duration of the target IGBT device; the third parameter thresholds include: the first voltage threshold, the first time threshold, the third current threshold, the fourth time threshold, the target on-voltage, and the fifth time threshold.

[0068] It can be understood that, in this step, the voltage, current and duration required for identifying the fault type can be acquired in advance and classified into a first target parameter, a second target parameter and a third target parameter.

[0069] 202. When the first inter-electrode voltage is less than the first voltage threshold and the second duration exceeds the first time threshold, and the current of the bypass thyristor is greater than the first current threshold and the first duration exceeds the second time threshold, it is determined that a low-voltage breakdown fault occurs in the bypass thyristor, and the fault type is a bypass thyristor low-voltage breakdown.

[0070] It should be noted that the first inter-electrode voltage refers to the voltage U between the collector and the emitter. ceT2 The second duration refers to the duration when the first inter-electrode voltage is less than the first voltage threshold. It can be understood that when the first inter-electrode voltage is less than the first voltage threshold, the timing of the duration is turned on, and the power module control board can obtain the first duration from the timing module inside it. The first duration refers to the duration when the current of the bypass thyristor is greater than the first current threshold. The acquisition principle can refer to the second duration, which will not be repeated here.

[0071] In this embodiment, when the power module control board detects the collector-emitter voltage U of the second IGBT device T2 ceT2 The measured value (i.e. the first inter-electrode voltage) is less than the set voltage threshold U set1(i.e. the first voltage threshold), and the duration exceeds the set time threshold T set1 (i.e. the first time threshold), and at the same time the bypass thyristor current I SCR Greater than the set current threshold I set1 (i.e. the first current threshold) and the duration exceeds the set time threshold T set2 (i.e., the second time threshold), after all the above conditions are met at the same time, the power module control board identifies the fault type as the "bypass thyristor low-voltage breakdown" of the half-bridge power module, and sends the identification result to the valve control system. Otherwise, the "bypass thyristor low-voltage breakdown" of the half-bridge power module will not be identified and will not be sent to the valve control system.

[0072] 203. When the first inter-pole voltage is less than the first voltage threshold and the first duration exceeds the first time threshold, and the current of the bypass switch is greater than the second current threshold and the third duration exceeds the third time threshold, and the issuance status of the bypass switch conduction instruction is not issued, and the bypass switch state is in the open state, it is determined that there is gap discharge in the bypass switch, and the fault type is gap discharge of the bypass switch.

[0073] It should be noted that the third duration refers to the duration during which the current of the bypass switch is greater than the second current threshold.

[0074] In this embodiment, the power module control board detects the voltage U between the collector and emitter of the second IGBT device T2. ceT2 The measured value is less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and at the same time detect the current value I of the bypass switch S S Greater than the set current threshold Iset2 And the duration exceeds the set time threshold T set3 At the same time, the power module control board has not issued a bypass switch conduction command and the bypass switch state sent by the bypass switch driver board is still in the open state. After the above conditions are met at the same time, the power module control board identifies the fault type as the half-bridge power module fault "bypass switch gap discharge" and sends the identification result to the valve control system. Otherwise, the "bypass switch gap discharge" of the half-bridge power module is not identified and is not sent to the valve control system.

[0075] If the power module control board detects that the measured value of the collector-emitter voltage UceT2 of the second IGBT device T2 is less than the set voltage threshold Uset1 and the duration exceeds the set time threshold Tset1, and at the same time detects the current value I of the bypass switch S S Greater than the set current threshold I set2 And the duration exceeds the set time threshold T set3At the same time, the power module control board has not issued a bypass switch conduction command and the bypass switch state sent by the bypass switch driver board is still in the open state. After the above conditions are met at the same time, the power module control board identifies the fault type as the "bypass switch gap discharge" of the half-bridge power module and sends the identification result to the valve control system. Otherwise, the "bypass switch gap discharge" of the half-bridge power module is not identified and is not sent to the valve control system.

[0076] 204. When the first inter-electrode voltage is less than the first voltage threshold and the first duration exceeds the first time threshold, and the current of the target IGBT device is greater than the third current threshold and the fourth duration exceeds the fourth time threshold, and the sending status of the target IGBT device turn-on instruction is not sent, and the second inter-electrode voltage is greater than the target turn-on voltage and the fifth duration is greater than the fifth time threshold, it is determined that the target IGBT device has a false triggering fault, and the fault type is false triggering of the IGBT device.

[0077] It should be noted that the fourth duration refers to the duration during which the current of the target IGBT device is greater than the third current threshold. The target on-voltage refers to the voltage value between the gate and the emitter required for turning on the target IGBT device.

[0078] In this embodiment, if the power module control board detects the collector-emitter voltage U of the second IGBT device T2 ceT2 The measured value is less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and at the same time detects the current value I of the second IGBT device T2 T2 Greater than the set current threshold I set3 And the duration exceeds the set time threshold T set4 At the same time, the power module control board did not issue the lower tube T2 conduction command, and detected the gate-emitter voltage U sent by the second IGBT device T2 driver board geT2 Greater than U ge开通 (The voltage between the gate and the emitter required to turn on the device, usually around +12V) and the duration exceeds the set time threshold T set5 When all the above conditions are met at the same time, the power module control board identifies the fault type as "the second IGBT device is falsely triggered by interference" of the half-bridge power module, and sends the identification result to the valve control system. Otherwise, the "second IGBT device is falsely triggered by interference" of the half-bridge power module will not be identified and will not be sent to the valve control system.

[0079] 205. When the first inter-electrode voltage is less than the first voltage threshold and the first duration exceeds the first time threshold, and the current of the target IGBT device is greater than the third current threshold and the fourth duration exceeds the fourth time threshold, and the sending status of the target IGBT device turn-on instruction is not sent, and the second inter-electrode voltage is less than the target turn-on voltage and the fifth duration is greater than the fifth time threshold, it is determined that the target IGBT device has a short-circuit failure fault, and the fault type is an IGBT device short-circuit failure fault.

[0080] It should be noted that the fourth parameter threshold includes a first voltage threshold, a first time threshold, a third current threshold, a fourth time threshold, a target on-voltage, and a sixth time threshold.

[0081] In this embodiment, if the power module control board detects the collector-emitter voltage U of the second IGBT device T2 ceT2 The measured value is less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and at the same time detects the current value I of the second IGBT device T2 T2 Greater than the set current threshold I set3 And the duration exceeds the set time threshold T set4 At the same time, the power module control board does not issue the second IGBT device T2 conduction instruction and detects the gate-emitter voltage U sent by the second IGBT device T2 drive board geT2 Less than U ge开通 (the voltage between the gate and the emitter required to turn on the device, usually around +12V) and the duration exceeds the set time threshold T set6 When all the above conditions are met at the same time, the power module control board identifies the fault type as "short circuit failure of the second IGBT device at rated voltage" of the half-bridge power module, and sends the identification result to the valve control system. Otherwise, the "short circuit failure of the second IGBT device at rated voltage" of the half-bridge power module will not be identified and will not be sent to the valve control system.

[0082] Based on the identification method provided by the embodiment of the present invention, the fault type of the through fault can be accurately identified, thereby accurately troubleshooting the faulty components and improving the fault identification efficiency. It can be understood that the identification method provided by this embodiment is applicable to both the identification scenario of a single fault type and the scenario where multiple fault types are superimposed. For example: Assuming that the detected through fault is caused by the superposition of multiple faults, the state of each component can still be identified according to the method of steps 201 to 205 above to obtain the corresponding identification results, and finally all the identification results are combined to obtain all the fault types that cause the through fault of the half-bridge power module.

[0083] It is understandable that there is no sequential order between step 202 to step 205, and they can be executed synchronously and in parallel.

[0084] Furthermore, the structure of the half-bridge power module may also include a third power switch device T3 and a second resistor R2, wherein the third power switch device T3 is provided with a parasitic diode D3; the third power switch device T3 is connected in series with the second resistor R2, and then connected in parallel with the first resistor R1.

[0085] Embodiment three:

[0086] When the power module is a full-bridge power module, such as Figure 4 As shown, its structure includes a bypass thyristor SCR, a bypass switch S, an IGBT component, a first capacitor C1 and a first resistor R1, a first power switch device T5 and a second resistor R2. The IGBT component includes a first IGBT device T1, a second IGBT device T2, a third IGBT device T3, and a fourth IGBT device T4. The first IGBT device T1 is also provided with a parasitic diode D1, the second IGBT device T2 is also provided with a parasitic diode D2, the third IGBT device T3 is also provided with a parasitic diode D3, and the fourth IGBT device T4 is also provided with a parasitic diode D4. The first power switch device T5 is also provided with a parasitic diode D5

[0087] The bypass thyristor SCR, the bypass switch S, and the second IGBT device T2 are connected in parallel in sequence, the first IGBT device T1 and the second IGBT device T2 are connected in series, the first capacitor C1 and the first IGBT device T1 and the second IGBT device T2 are connected in parallel, and the first resistor R1 is connected in parallel with the first capacitor C1; the third IGBT device T3 and the fourth IGBT device T4 are connected in series and in parallel with the first resistor R1, and the first power switch device T5 is connected in series with the second resistor R2 and in parallel with the first resistor R1.

[0088] Among them, the bypass thyristor SCR, the bypass switch S, the first IGBT device T1, the second IGBT device T2, the third IGBT device T3, and the fourth IGBT device T4 are respectively connected in series with the Hall sensors CT1, CT2, CT3, CT4, CT5, and CT6; the Hall sensors CT1, CT2, CT3, CT4, CT5, and CT6 are connected to the power module control board and are used to measure the current value I flowing through the bypass thyristor SCR, the bypass switch S, the first IGBT device T1, the second IGBT device T2, the third IGBT device T3, and the fourth IGBT device T4 in real time. SCR ,I S ,I T1 ,I T2 ,I T3 ,I T4 , and sent to the power module control board.

[0089] The driving board of the first IGBT device T1 is connected to the first IGBT device T1 and the power module control board, and is used to measure the collector-emitter voltage U of the first IGBT device T1 in real time. ceT1 , the gate-emitter voltage U of the first IGBT device T1 geT1 , and sent to the power module control board in time.

[0090] The driving board of the second IGBT device T2 is connected to the second IGBT device T2 and the power module control board, and is used to measure the collector-emitter voltage U of the second IGBT device T2 in real time. ceT2 , the gate-emitter voltage U of the second IGBT device T2 geT2 , and sent to the power module control board in time.

[0091] The driving board of the third IGBT device T3 is connected to the third IGBT device T3 and the power module control board, and is used to measure the collector-emitter voltage U of the third IGBT device T3 in real time. ceT3 , the gate-emitter voltage U of the third IGBT device T3 geT3 , and sent to the power module control board in time.

[0092] The drive board of the fourth IGBT device T4 is connected to the fourth IGBT device T4 and the power module control board, and is used to measure the collector-emitter voltage U of the fourth IGBT device T4 in real time. ceT4 , the gate-emitter voltage U of the fourth IGBT device T4 geT4 , and sent to the power module control board in time.

[0093] Among them, the current I SCR ,I S ,I T1 ,I T2 ,I T3 ,I T4 direction, such as Figure 4 As shown, the direction indicated by the arrow is the positive direction. The input state of the full-bridge power module includes a positive input state and a negative input state. When in the positive input state, the first IGBT device T1 and the fourth IGBT device T4 are turned on, and the second IGBT device T2 and the third IGBT device T3 are turned off. When in the negative input state, the first IGBT device T1 and the fourth IGBT device T4 are turned off, and the second IGBT device T2 and the third IGBT device T3 are turned on.

[0094] If a direct fault occurs to the DC capacitor of the full-bridge power module during the input state, the fault type can be identified by the converter valve power module fault type identification method provided by the following embodiment of the present invention, thereby determining the cause of the direct fault of the full-bridge power module. In this embodiment, the target IGBT device includes any one of the two IGBT devices in the off state in the full-bridge power module in the input state.

[0095] Furthermore, if Figure 5 As shown, a method for identifying a fault type of a converter valve power module provided by an embodiment of the present invention is applied to a power module control board, and the steps specifically include:

[0096] 301. Obtain a first target parameter, a second target parameter, a third target parameter, a bypass switch state, a status of issuing a bypass switch on instruction, and a status of issuing a target IGBT device on instruction.

[0097] It should be noted that the first target parameter of this step includes the current and the first duration, the first inter-electrode voltage difference, the second inter-electrode voltage difference, and the sixth duration of the bypass thyristor; the first parameter threshold includes the first voltage threshold, the first current threshold, the first time threshold, and the second time threshold. The second target parameter includes the current and the third duration, the first inter-electrode voltage difference, the second inter-electrode voltage difference, and the sixth duration of the bypass switch; the second parameter threshold includes the first voltage threshold, the first time threshold, the second current threshold, and the third time threshold.

[0098] The first inter-electrode voltage difference is U ceT2 -U ceT4 Among them, U ceT2 is the voltage between the collector and the emitter of the second IGBT device T2; U ceT4 is the collector-emitter voltage of the fourth IGBT device T4.

[0099] The second inter-electrode voltage difference is U ceT3 -U ceT1 Among them, U ceT3 is the collector-emitter voltage of the third IGBT device T3; U ceT1 is the collector-emitter voltage of the first IGBT device T1.

[0100] The sixth duration refers to the duration during which both the first inter-electrode voltage difference and the second inter-electrode voltage difference are smaller than the first voltage threshold.

[0101] It can be understood that the first parameter threshold, the second parameter threshold, the third parameter threshold, and the fourth parameter threshold are the same as those in the second embodiment, and the details can be referred to in the second embodiment.

[0102] 302. When the first inter-electrode voltage difference and the second inter-electrode voltage difference are both smaller than the first voltage threshold and the sixth duration exceeds the first time threshold, and the current of the bypass thyristor is greater than the first current threshold and the first duration exceeds the second time threshold, it is determined that a low-voltage breakdown fault occurs in the bypass thyristor, and the fault type is a bypass thyristor low-voltage breakdown.

[0103] It should be noted that in this step, when the first inter-electrode voltage difference and the second inter-electrode voltage difference are both less than the first voltage threshold and the sixth duration exceeds the first time threshold, and the current of the bypass thyristor is greater than the first current threshold and the first duration exceeds the second time threshold, it indicates that a low-voltage breakdown fault has occurred in the bypass thyristor at this time, and therefore it is determined that a low-voltage breakdown has occurred in the bypass thyristor, and the fault type at this time is a low-voltage breakdown of the bypass thyristor.

[0104] 303. When the first inter-pole voltage difference and the second inter-pole voltage difference are both smaller than the first voltage threshold and the sixth duration exceeds the first time threshold, and the current of the bypass switch is greater than the second current threshold and the third duration exceeds the third time threshold, and the bypass switch conduction instruction is not issued, and the bypass switch is in the open state, it is determined that there is gap discharge in the bypass switch, and the fault type is gap discharge of the bypass switch.

[0105] It should be noted that in this step, the first inter-pole voltage difference and the second inter-pole voltage difference are both smaller than the first voltage threshold and the sixth duration exceeds the first time threshold, and the current of the bypass switch is greater than the second current threshold and the third duration exceeds the third time threshold, and the issuance status of the bypass switch conduction instruction is not issued, and when the bypass switch state is in the open state, it indicates that there is gap discharge in the bypass switch, and therefore it is determined that there is gap discharge in the bypass switch, that is, the fault type at this time is gap discharge of the bypass switch.

[0106] 304. According to the comparison result between the third target parameter and the preset third parameter threshold value and the issuing status of the target IGBT device conduction instruction, determine whether the target IGBT device has a false triggering fault; if so, determine that the fault type is a false triggering of the IGBT device.

[0107] 305. According to the comparison result between the third target parameter and the preset fourth parameter threshold value and the issuing status of the target IGBT device conduction instruction, determine whether the target IGBT device has a short circuit failure fault; if so, determine that the fault type is an IGBT device short circuit failure fault.

[0108] It should be noted that the principle of step 304 is similar to that of step 204, and the principle of step 305 is similar to that of step 205. The difference is that in this embodiment, when in the positive input state, the target IGBT device is the second IGBT device T2 or the third IGBT device T3.

[0109] When the target IGBT device is the second IGBT device T2 , the current of the target IGBT device is the current of the second IGBT device T2 , and the first inter-electrode voltage of the target IGBT device is the collector-emitter voltage of the second IGBT device T2 .

[0110] When the target IGBT device is the third IGBT device T3 , the current of the target IGBT device is the current of the third IGBT device T3 , and the first inter-electrode voltage of the target IGBT device is the collector-emitter voltage of the third IGBT device T3 .

[0111] When in the negative input state, the target IGBT device is the first IGBT device T1 or the fourth IGBT device T4 .

[0112] When the target IGBT device is the first IGBT device T1 , the current of the target IGBT device is the current of the first IGBT device T1 , and the first inter-electrode voltage of the target IGBT device is the collector-emitter voltage of the first IGBT device T1 .

[0113] When the target IGBT device is the fourth IGBT device T4 , the current of the target IGBT device is the current of the fourth IGBT device T4 , and the first inter-electrode voltage of the target IGBT device is the collector-emitter voltage of the fourth IGBT device T4 .

[0114] It is understandable that in this embodiment, step 303 and step 304 may be performed for each target IGBT device respectively until a fault identification result of each target IGBT device is obtained. There is no sequence between step 302 and step 305, and they may be performed synchronously and in parallel.

[0115] Based on the above, it can be seen that when a straight-through fault occurs in the full-bridge power module, the identification method provided in this embodiment can accurately identify the faulty components and fault types that cause the straight-through fault in the full-bridge power module, thereby reducing the time required for troubleshooting and improving the efficiency of troubleshooting.

[0116] In one application example, the Figure 4 The structure shown further illustrates the identification method provided in Example 3.

[0117] In this application example, according to the input state of the full-bridge power module, it can be divided into a positive input state and a negative input state.

[0118] (I) When the full-bridge power module is in the positive input state, the first IGBT device T1 and the fourth IGBT device T4 are turned on, and the second IGBT device T2 and the third IGBT device T3 are turned off. At this time, if a direct fault occurs in the DC capacitor of the full-bridge power module, then:

[0119] (1) If the power module control board detects (U ceT2 -U ceT4 ) measured value and (U ceT3 -U ceT1 ) The measured values ​​are all less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and the bypass thyristor current I SCR Greater than the set current threshold I set1 And the duration exceeds the set time threshold T set2 When all the above conditions are met at the same time, the power module control board identifies the fault type as "bypass thyristor low-voltage breakdown" of the full-bridge power module and sends the identification result to the valve control system. Otherwise, the "bypass thyristor low-voltage breakdown" of the full-bridge power module is not identified and is not sent to the valve control system.

[0120] (2) If the power module control board detects (U ceT2 -U ceT4 ) measured value and (U ceT3 -U ceT1 ) The measured values ​​are all less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and at the same time detect the current value I of the bypass switch S S Greater than the set current threshold I set2 And the duration exceeds the set time threshold T set3 At the same time, the power module control board has not issued a bypass switch conduction command and the bypass switch state sent by the bypass switch driver board is still in the open state. After the above conditions are met at the same time, the power module control board identifies the fault type as the "bypass switch gap discharge" of the full-bridge power module and sends the identification result to the valve control system. Otherwise, the "bypass switch gap discharge" of the full-bridge power module is not identified and is not sent to the valve control system.

[0121] (3) If the power module control board detects the collector-emitter voltage U of the second IGBT device T2 (or the third IGBT device T3) ceT2 (or U ceT3 )The measured value is less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and at the same time detect the current value I of the second IGBT device T2 (or the third IGBT device T3) T2 (or IT3 ) is greater than the set current threshold I set3 And the duration exceeds the set time threshold T set4 At the same time, the power module control board does not issue the second IGBT device T2 (or the third IGBT device T3) conduction command, and detects the gate-emitter voltage U sent by the second IGBT device T2 (or the third IGBT device T3) drive board. geT2 (or U geT3 ) is greater than U ge开通 (The voltage between the gate and the emitter required to turn on the device, usually around +12V) and the duration exceeds the set time threshold T set5 When all the above conditions are met at the same time, the power module control board identifies the fault type as "IGBT device is falsely triggered by interference" of the second IGBT device T2 (or the third IGBT device T3) of the full-bridge power module, and sends the identification result to the valve control system. Otherwise, the second IGBT device T2 (or the third IGBT device T3) of the full-bridge power module "IGBT device is falsely triggered by interference" will not be identified and will not be sent to the valve control system.

[0122] (4) If the power module control board detects the collector-emitter voltage U of the second IGBT device T2 (or the third IGBT device T3) ceT2 (or U ceT3 )The measured value is less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and at the same time detect the current value I of the second IGBT device T2 (or the third IGBT device T3) T2 (or I T3 ) is greater than the set current threshold I set3 And the duration exceeds the set time threshold T set4 At the same time, the power module control board does not issue the second IGBT device T2 (or the third IGBT device T3) conduction instruction and detects the gate-emitter voltage U sent by the second IGBT device T2 (or the third IGBT device T3) drive board. geT2 (or U geT3 ) is less than U ge开通 (The voltage between the gate and the emitter required to turn on the device, usually around +12V) and the duration exceeds the set time threshold T set6 When all the above conditions are met at the same time, the power module control board identifies the fault type as "IGBT device short-circuit failure under rated voltage" of the second IGBT device T2 (or the third IGBT device T3) of the full-bridge power module, and sends the identification result to the valve control system. Otherwise, the second IGBT device T2 (or the third IGBT device T3) of the full-bridge power module "IGBT device short-circuit failure under rated voltage" will not be identified and will not be sent to the valve control system.

[0123] Based on the identification method provided by the embodiment of the present invention, the fault type of the through fault can be accurately identified, thereby accurately troubleshooting the faulty components and improving the fault identification efficiency. It can be understood that the identification method provided by this embodiment is applicable to both the identification scenario of a single fault type and the scenario where multiple fault types are superimposed. For example: Assuming that the detected through fault is caused by the superposition of multiple faults, the state of each component can still be identified according to the above method to obtain the corresponding identification result, and finally all the identification results are combined to obtain all the fault types that cause the through fault in the positive input state of the full-bridge power module.

[0124] (ii) When the full-bridge power module is in the negative input state, the second IGBT device T2 and the third IGBT device T3 are turned on, and the first IGBT device T1 and the fourth IGBT device T4 are turned off. At this time, if a direct fault occurs in the DC capacitor of the full-bridge power module, then:

[0125] (5) If the power module control board detects (U ceT2 -U ceT4 ) measured value and (U ceT3 -U ceT1 ) The measured values ​​are all less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and the bypass thyristor current I SCR Greater than the set current threshold I set1 And the duration exceeds the set time threshold T set2 When all the above conditions are met at the same time, the power module control board identifies the fault type as "bypass thyristor low-voltage breakdown" of the full-bridge power module and sends the identification result to the valve control system. Otherwise, the "bypass thyristor low-voltage breakdown" of the full-bridge power module is not identified and is not sent to the valve control system.

[0126] (6) If the power module control board detects (U ceT2 -U ceT4 ) measured value and (U ceT3 -U ceT1 ) The measured values ​​are all less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and at the same time detect the current value I of the bypass switch S S Greater than the set current threshold I set2 And the duration exceeds the set time threshold T set3At the same time, the power module control board has not issued a bypass switch conduction command and the bypass switch state sent by the bypass switch driver board is still in the open state. After the above conditions are met at the same time, the power module control board identifies the fault type as the "bypass switch gap discharge" of the full-bridge power module and sends the identification result to the valve control system. Otherwise, the "bypass switch gap discharge" of the full-bridge power module is not identified and is not sent to the valve control system.

[0127] (7) If the power module control board detects the collector-emitter voltage U of the first IGBT device T1 (or the fourth IGBT device T4) ceT1 (or U ceT4 )The measured value is less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and at the same time detect the current value I of IGBT T1 (or IGBT T4) T1 (or I T4 ) is greater than the set current threshold I set3 And the duration exceeds the set time threshold T set4 At the same time, the power module control board does not issue the first IGBT device T1 (or the fourth IGBT device T4) conduction instruction, and detects the gate-emitter voltage U sent by the first IGBT device T1 (or the fourth IGBT device T4) drive board. geT1 (or U geT4 ) is greater than U ge开通 (the voltage between the gate and the emitter required to turn on the device, usually around +12V) and the duration exceeds the set time threshold T set5 When all the above conditions are met at the same time, the power module control board identifies the fault type as "IGBT device is erroneously triggered by interference" of the first IGBT device T1 (or the fourth IGBT device T4) of the full-bridge power module, and sends the identification result to the valve control system; otherwise, the first IGBT device T1 (or the fourth IGBT device T4) of the full-bridge power module "IGBT device is erroneously triggered by interference" will not be identified and will not be sent to the valve control system.

[0128] (8) If the power module control board detects the collector-emitter voltage U of the first IGBT device T1 (or the fourth IGBT device T4) ceT1 (or U ceT4 )The measured value is less than the set voltage threshold U set1 And the duration exceeds the set time threshold T set1 , and at the same time detect the current value I of IGBT T1 (or IGBT T4) T1 (or I T4 ) is greater than the set current threshold I set3 And the duration exceeds the set time threshold T set4At the same time, the power module control board does not issue the first IGBT device T1 (or the fourth IGBT device T4) conduction instruction and detects the gate-emitter voltage U sent by the first IGBT device T1 (or the fourth IGBT device T4) drive board geT1 (or U geT4 ) is less than U ge开通 (the voltage between the gate and the emitter required to turn on the device, usually around +12V) and the duration exceeds the set time threshold T set6 When all the above conditions are met at the same time, the power module control board identifies the fault type as "IGBT device short-circuit failure under rated voltage" of the first IGBT device T1 (or the fourth IGBT device T4) of the full-bridge power module, and sends the identification result to the valve control system. Otherwise, the "IGBT device short-circuit failure under rated voltage" of the first IGBT device T1 (or the fourth IGBT device T4) of the full-bridge power module will not be identified and will not be sent to the valve control system.

[0129] Based on the identification method provided by the embodiment of the present invention, the fault type of the through fault can be accurately identified, thereby accurately troubleshooting the faulty components and improving the fault identification efficiency. It can be understood that the identification method provided by this embodiment is applicable to both the identification scenario of a single fault type and the scenario where multiple fault types are superimposed. For example: Assuming that the detected through fault is caused by the superposition of multiple faults, the state of each component can still be identified according to the above method to obtain the corresponding identification result, and finally all the identification results are combined to obtain all the fault types that cause the through fault under the negative input state of the full-bridge power module.

[0130] In one embodiment, a device for identifying a fault type of a converter valve power module is also provided, the device comprising a processor and a memory;

[0131] The memory is used to store the program code and transmit the program code to the processor;

[0132] The processor is configured to execute the method of any of the above embodiments according to the instructions in the program code.

[0133] The identification method and device proposed in the present invention can accurately identify which component failure in the module caused the through-fault when the flexible DC converter valve power module is in the "on-state" (half-bridge power module is in the on-state, full-bridge power module is in the positive on-state or negative on-state) after being unlocked. Among them, the identifiable component failure types include: IGBT device false triggering due to interference, short circuit failure under rated voltage of the device, bypass switch gap discharge, and thyristor low-voltage breakdown. Therefore, the present invention can accurately identify the faulty device and fault type that cause the through-fault, improve the efficiency of fault identification, and solve the technical problems of the existing fault identification method that takes a long time and is inefficient.

[0134] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0135] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0136] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0137] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each functional unit may be physically separate, or two or more functional units may be integrated into one processing unit. The above integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0138] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0139] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0140] It should also be noted that in the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present invention.

[0141] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for identifying fault types of converter valve power modules, characterized in that: The power module includes a bypass thyristor, a bypass switch, and an IGBT component; the IGBT component includes a target IGBT device; When the power module is in an on-state and a through fault occurs, the method includes: Obtaining a first target parameter, a second target parameter, a third target parameter, a bypass switch state, a state of issuing a bypass switch on instruction, and a state of issuing a target IGBT device on instruction; According to the comparison result of the first target parameter and the preset first parameter threshold, judging whether the bypass thyristor has a low-voltage breakdown fault, and if so, judging that the fault type is a bypass thyristor low-voltage breakdown; According to the comparison result of the second target parameter and the preset second parameter threshold, the bypass switch state and the issuing state of the bypass switch conduction instruction, it is judged whether there is gap discharge of the bypass switch, and if so, it is determined that the fault type is gap discharge of the bypass switch; According to the comparison result of the third target parameter and the preset third parameter threshold value and the issuing state of the target IGBT device conduction instruction, it is judged whether the target IGBT device has a false triggering fault, and if so, it is determined that the fault type is a false triggering of the IGBT device; According to the comparison result of the third target parameter and the preset fourth parameter threshold value and the issuing status of the target IGBT device conduction instruction, it is judged whether the target IGBT device has a short circuit failure fault. If so, the fault type is determined to be an IGBT device short circuit failure fault.

2. The method according to claim 1, characterized in that The first target parameter includes a current and a first duration of the bypass thyristor, a first inter-electrode voltage and a second duration of the target IGBT device; The first parameter threshold comprises a first voltage threshold, a first current threshold, a first time threshold and a second time threshold; The step of judging whether a low-voltage breakdown fault occurs in the bypass thyristor according to a comparison result between the first target parameter and a preset first parameter threshold value includes: When the first inter-electrode voltage is less than the first voltage threshold and the second duration exceeds a first time threshold, and the current of the bypass thyristor is greater than the first current threshold and the first duration exceeds a second time threshold, it is determined that a low-voltage breakdown fault occurs in the bypass thyristor.

3. The method according to claim 2, characterized in that The second target parameter includes a first inter-electrode voltage and a second duration of the target IGBT device, and a current and a third duration of the bypass switch; The second parameter threshold includes the first voltage threshold, the first time threshold, a second current threshold and a third time threshold; The step of judging whether there is gap discharge in the bypass switch according to the comparison result of the second target parameter and the preset second parameter threshold, the bypass switch state and the issuing state of the bypass switch conduction instruction includes: When the first inter-pole voltage is less than the first voltage threshold and the first duration exceeds the first time threshold, and the current of the bypass switch is greater than the second current threshold and the third duration exceeds the third time threshold, and the issuance status of the bypass switch conduction instruction is not issued, and the bypass switch state is in the open state, it is determined that the bypass switch has gap discharge.

4. The method according to claim 3, characterized in that The third target parameter includes: the first inter-electrode voltage and the second duration of the target IGBT device, the current and the fourth duration of the target IGBT device, the second inter-electrode voltage and the fifth duration of the target IGBT device; the third parameter threshold includes: the first voltage threshold, the first time threshold, the third current threshold, the fourth time threshold, the target on-voltage, and the fifth time threshold; The step of judging whether the target IGBT device has a false triggering fault according to a comparison result of the third target parameter and a preset third parameter threshold value and a status of issuing a turn-on instruction of the target IGBT device comprises: When the first inter-pole voltage is less than the first voltage threshold and the first duration exceeds the first time threshold, and the current of the target IGBT device is greater than the third current threshold and the fourth duration exceeds the fourth time threshold, and the sending status of the target IGBT device turn-on instruction is not sent, and the second inter-pole voltage is greater than the target turn-on voltage and the fifth duration is greater than the fifth time threshold, it is determined that the target IGBT device has a false triggering fault.

5. The method according to claim 4, characterized in that The fourth parameter threshold includes the first voltage threshold, the first time threshold, the third current threshold, the fourth time threshold, the target on-voltage, and a sixth time threshold; The step of judging whether the target IGBT device has a short-circuit failure fault according to the comparison result of the third target parameter and the preset fourth parameter threshold value and the issuing state of the target IGBT device conduction instruction comprises: When the first inter-pole voltage is less than the first voltage threshold and the first duration exceeds the first time threshold, and the current of the target IGBT device is greater than the third current threshold and the fourth duration exceeds the fourth time threshold, and the sending status of the target IGBT device turn-on instruction is not sent, and the second inter-pole voltage is less than the target turn-on voltage and the fifth duration is greater than the fifth time threshold, it is determined that the target IGBT device has a short-circuit failure fault.

6. The method according to claim 1, characterized in that When the power module is a full-bridge power module, the first target parameter includes the current and the first duration of the bypass thyristor, the first inter-electrode voltage difference, the second inter-electrode voltage difference, and the sixth duration; The first parameter threshold comprises a first voltage threshold, a first current threshold, a first time threshold and a second time threshold; The step of judging whether a low-voltage breakdown fault occurs in the bypass thyristor according to a comparison result between the first target parameter and a preset first parameter threshold value includes: When the first inter-electrode voltage difference and the second inter-electrode voltage difference are both smaller than the first voltage threshold and the sixth duration exceeds the first time threshold, and the current of the bypass thyristor is greater than the first current threshold and the first duration exceeds the second time threshold, it is determined that a low-voltage breakdown fault occurs in the bypass thyristor.

7. The method according to claim 6, characterized in that The second target parameter includes the current and the third duration of the bypass switch, the first inter-electrode voltage difference, the second inter-electrode voltage difference, and the sixth duration; The second parameter threshold includes the first voltage threshold, the first time threshold, a second current threshold and a third time threshold; The step of judging whether there is gap discharge in the bypass switch according to the comparison result of the second target parameter and the preset second parameter threshold, the bypass switch state and the issuing state of the bypass switch conduction instruction includes: When the first inter-pole voltage difference and the second inter-pole voltage difference are both smaller than the first voltage threshold and the sixth duration exceeds the first time threshold, and the current of the bypass switch is greater than the second current threshold and the third duration exceeds the third time threshold, and the issuance status of the bypass switch conduction instruction is not issued, and the bypass switch state is in the open state, it is determined that there is gap discharge in the bypass switch.

8. The method according to claim 5, characterized in that When the power module is a half-bridge power module, the target IGBT device is an IGBT device in a cut-off state in the half-bridge power module in an on state.

9. The method according to claim 5, characterized in that When the power module is a full-bridge power module, the target IGBT device includes any one of two IGBT devices in the off state in the full-bridge power module in the on state.

10. A device for identifying fault types of converter valve power modules, characterized in that: The device comprises a processor and a memory; The memory is used to store program code and transmit the program code to the processor; The processor is configured to execute the method according to any one of claims 1 to 9 according to the instructions in the program code.

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