Failure detection circuit and method for absorption diode in IGCT power module

Abstract

The invention discloses a failure detection circuit and method for an absorption diode in an IGCT power module, the circuit comprises a detection module and a control module which are connected in sequence, the detection module is electrically connected with a to-be-detected IGCT power module and is used for detecting current in a suppression reactor in the IGCT power module, the detection module is used for transmitting a detection signal to the control module, and the control module is used for controlling the absorption diode in the IGCT power module. And the control module is used for judging whether the absorption diode fails or not according to a detection signal of the detection module, outputting a control signal to the IGCT power module and controlling the working state of each IGCT device. The detection module detects the bus voltage of the converter, the pulse starting signal of the IGCT power module and the current signal on the suppression reactor, and judges whether the absorption diode fails or not according to the detection result of the current signal on the suppression reactor when the bus voltage is normal and the IGCT power module is started, so that the damage probability of the IGCT power module is reduced, and the service life of the IGCT power module is prolonged. And the operation reliability of the IGCT power module is enhanced.

Description

Technical Field

[0001] This invention relates to the field of IGCT power module technology, and in particular to a failure detection circuit and method for the absorption diode in an IGCT power module. Background Technology

[0002] Medium-voltage IGCT (Integrated Gate-commutated Thyristor) converters are widely used in metallurgy, shipbuilding, wind power, and other fields, where the application scenarios place extremely high demands on the converter's stability. In the metallurgical field, IGCT converters serve as the main drive system to complete steel rolling, and failures during the rolling process are not allowed to affect the continuity of production tasks. In the shipbuilding field, IGCT converters drive motors to provide power to ships, and failures during operation cannot affect the ship's navigation. In the wind power field, IGCT converters connect the electricity output from wind turbines to the grid, and shutdowns during power generation cannot affect the conversion of electrical energy.

[0003] To ensure the continuous and reliable operation of IGCT converters, both appropriate electrical component selection and circuit design are necessary, as is real-time monitoring and assessment of the entire converter's operating status. As the most crucial component of the converter, the medium-voltage IGCT power module requires careful monitoring and assessment of its operating status during converter operation. While a failure of the snubber diode in the snubber circuit may not immediately cause module failure, prolonged operation can lead to its eventual malfunction.

[0004] Therefore, real-time monitoring of the absorption diode status to reduce the probability of IGCT power module failure is an urgent problem to be solved. Summary of the Invention

[0005] The purpose of this invention is to solve at least one of the above problems.

[0006] This invention provides a failure detection circuit and method for the absorption diode in an IGCT power module. By detecting the current on the reactor in the IGCT power module in real time, it determines whether the absorption diode has failed. When the absorption diode failure is detected, an alarm is issued, which reduces the probability of damage to the IGCT power module and enhances the reliability of the IGCT power module operation.

[0007] In a first aspect, the present invention provides a failure detection circuit for the absorption diode in an IGCT power module, which is achieved through the following technical solution:

[0008] A failure detection circuit for the absorption diode in an IGCT power module includes: a detection module and a control module;

[0009] The detection module is used to detect the current signal of the suppression reactor in the IGCT power module, obtain the voltage signal, and transmit the detected voltage signal to the control module. The suppression reactor and the absorption diode are located together in the absorption circuit of the IGCT power module.

[0010] The control module is used to determine whether the absorption diode has failed based on the voltage signal detected by the detection module, and to output a control signal to the IGCT power module based on the determination result, so as to control the working state of each IGCT device in the IGCT power module.

[0011] The present invention is further configured such that the detection module includes a start-up detection circuit and a current detection circuit.

[0012] The startup detection circuit is used to detect the bus voltage signal of the converter where the IGCT power module is located and the pulse startup signal output by the converter for the IGCT power module, and transmit the detected signals to the control module.

[0013] The current detection circuit is used to receive the detection command signal issued by the control module, detect the current signal flowing through the suppression reactor according to the detection command signal, and transmit the detected voltage signal to the control module; the detection command is generated by the control module based on the bus voltage signal and the pulse start signal.

[0014] The present invention is further configured such that the current detection circuit includes: a current sensing unit and a signal processing unit connected in sequence;

[0015] The current sensing unit is used to sense the current signal in the suppression reactor and obtain the induced voltage signal;

[0016] The signal processing unit is used to perform amplitude conversion on the sensed voltage signal to obtain a voltage signal, and transmit the voltage signal to the control module;

[0017] The control module determines whether the absorption diode has failed based on the voltage signal received from the signal processing unit, and outputs a control signal to the IGCT power module according to the determination result, so as to control the working state of each IGCT device in the IGCT power module.

[0018] The present invention is further configured such that the current sensing unit includes a secondary coil, the secondary coil being used to form an air-core transformer with the suppression reactor, current flowing through the suppression reactor, and when there is voltage across the suppression reactor, the secondary coil generates an induced voltage signal proportional to the voltage across the suppression reactor.

[0019] The signal processing unit is used to perform amplitude conversion processing on the induced voltage signal to obtain a voltage signal, and then transmit the obtained voltage signal to the control module.

[0020] The present invention is further configured such that the signal processing unit includes a first voltage divider subunit and a voltage regulator subunit connected in sequence;

[0021] The first voltage divider subunit is used to divide the voltage signal in the secondary coil to generate a voltage divider signal;

[0022] The voltage regulator subunit is used to regulate the voltage divider signal and transmit the resulting regulated signal as the voltage signal to the control module.

[0023] The present invention is further configured such that the signal processing unit further includes:

[0024] The signal transmitting subunit is used to convert the regulated signal into a first light-emitting signal and transmit the first light-emitting signal to the control module;

[0025] The control module determines whether the absorption diode is faulty based on the first light emission signal received from the signal transmission subunit, and outputs a control signal to the IGCT power module according to the determination result, so as to control the working state of each IGCT device in the IGCT power module.

[0026] The present invention is further configured such that the start-up detection circuit includes: a bus voltage detection unit and a pulse start-up detection unit;

[0027] The bus voltage detection unit is used to detect the bus voltage signal of the converter where the IGCT power module is located, and transmit the bus voltage signal to the control module.

[0028] The pulse start detection unit is used to detect the pulse start signal of the converter for the IGCT power module and transmit the pulse start signal to the control module.

[0029] The control module is used to generate the detection command signal and send it to the current detection circuit when the bus voltage signal indicates that the bus voltage is within the normal operating range and the pulse start signal indicates that the IGCT power module is in normal operating condition.

[0030] Secondly, the failure detection aspect of the absorption diode in the IGCT power module of the present invention is achieved through the following technical solution:

[0031] A method for detecting the failure of the absorption diode in an IGCT power module, comprising:

[0032] The current signal of the suppression reactor in the IGCT power module is detected to obtain the voltage signal; the suppression reactor and the absorption diode are located together in the absorption circuit of the IGCT power module.

[0033] Based on the voltage signal, it is determined whether the absorption diode has failed, and the working state of each IGCT device in the IGCT power module is controlled according to the determination result.

[0034] The present invention is further characterized in that, before detecting the current signal of the suppression reactor in the IGCT power module, it further includes:

[0035] The bus voltage signal of the converter where the IGCT power module is located and the pulse start signal output by the converter for the IGCT power module are detected.

[0036] When it is determined that the bus voltage signal indicates that the bus voltage is within the normal operating range, and the pulse start signal indicates that the IGCT power module is in normal operating condition, the step of detecting the current signal of the suppression reactor in the IGCT power module is executed.

[0037] The present invention is further configured such that determining whether the absorption diode has failed based on the voltage signal, and controlling the operating state of each IGCT device in the IGCT power module based on the determination result, includes:

[0038] If the voltage signal is periodic, and the duration of the zero voltage signal exceeds a set time, the absorption diode is determined to be faulty; otherwise, the absorption diode is determined to be normal.

[0039] Thirdly, the computer device of the present invention is achieved through the following technical solution:

[0040] A computer device includes a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the method described in this application.

[0041] Fourthly, the present invention provides a computer-readable storage medium, which is implemented by the following technical solution: a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in this application.

[0042] Fifthly, a computer program product of the present invention is implemented by the following technical solution: a computer program product comprising a computer program that, when executed by a processor, implements the method described in this application.

[0043] Compared with the prior art, the beneficial technical effects of this application are as follows:

[0044] 1. This application detects the current in the suppression reactor and monitors the status of the absorption diode in real time, which can promptly detect absorption diode failure, reduce the probability of IGCT power module damage, and enhance the reliability of IGCT power module operation;

[0045] 2. Furthermore, this application determines the normal operation of the IGCT power module by detecting the bus voltage and pulse start signal, and detects the current in the damping reactor, thus preventing misjudgment when the IGCT power module has not started due to normal bus voltage, and improving the accuracy of detection reliability. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of a failure detection circuit structure according to a specific embodiment of this application;

[0047] Figure 2 This is a circuit structure diagram of an existing IGCT power module;

[0048] Figure 3 This is a schematic diagram of the signal processing unit structure according to a specific embodiment of this application;

[0049] Figure 4 This is a schematic diagram of the equivalent circuit structure of the suppression reactor and the secondary coil in a specific embodiment of this application;

[0050] Figure 5 This is a schematic diagram of a failure detection circuit according to a specific embodiment of this application;

[0051] Figure 6 This is a schematic diagram of the bus voltage detection unit structure according to a specific embodiment of this application. Detailed Implementation

[0052] The present invention will be further described in detail below with reference to the accompanying drawings.

[0053] This application discloses a failure detection circuit for the absorption diode in an IGCT power module, such as... Figure 1 As shown, it includes a detection module and a control module. The detection module is electrically connected to the IGCT power module under test and is used to detect the current signal in the suppression reactor of the IGCT power module to obtain a voltage signal. The detection module is connected to the control module and is used to transmit the detected voltage signal to the control module. The control module is used to determine whether the absorption diode has failed based on the voltage signal from the detection module, and outputs a control signal to the IGCT power module based on the determination result to control the conduction or cutoff of each IGCT device, thereby controlling the working state of the IGCT power module.

[0054] The IGCT power module is used in the converter. When there is current on the converter bus and the bus voltage is within the normal operating range, the converter control center sends a pulse start signal to the IGCT power module. After receiving the pulse start signal, the IGCT power module enters the working state. If the IGCT power module is damaged and cannot work, the converter will not work because it has detected the IGCT power module.

[0055] like Figure 2 As shown, the IGCT power module includes an upper half-bridge absorption circuit, a lower half-bridge absorption circuit, and a half-bridge circuit. The upper half-bridge absorption circuit and the lower half-bridge absorption circuit are connected together, and the combination of the upper half-bridge absorption circuit and the lower half-bridge absorption circuit is connected to the half-bridge circuit. The first terminal of the upper half-bridge absorption circuit and the first terminal of the lower half-bridge absorption circuit are respectively connected to the two ends of the DC power supply. The second terminal of the upper half-bridge absorption circuit and the second terminal of the lower half-bridge absorption circuit are respectively connected to the two ends of the half-bridge circuit. The third terminal of the upper half-bridge absorption circuit and the third terminal of the lower half-bridge absorption circuit are connected to the third terminal NP of the half-bridge circuit. The fourth terminal of the lower half-bridge absorption circuit serves as the output terminal of the IGCT power module.

[0056] The upper half-bridge absorption circuit includes a first suppression reactor L1, a first suppression resistor R1, a first absorption diode D7, and a first absorption capacitor C1. One end of the first suppression reactor and one end of the first suppression resistor are connected together as the first terminal of the upper half-bridge absorption circuit, which is connected to the positive terminal DC+ of the DC voltage. The other end of the first suppression reactor and the positive terminal of the first absorption diode are connected together as the second terminal of the upper half-bridge absorption circuit, which is connected to one end of the half-bridge circuit. The other end of the first suppression resistor and the negative terminal of the first absorption diode are connected to one end of the first absorption capacitor. The other end of the first absorption capacitor serves as the third terminal of the upper half-bridge absorption circuit, which is connected to the second terminal of the lower half-bridge absorption circuit and to the first terminal NP of the half-bridge circuit.

[0057] The lower half-bridge absorption circuit includes a second suppression reactor L2, a second suppression resistor R2, a second absorption diode D8, and a second absorption capacitor C2. One end of the first suppression reactor L2 and one end of the first suppression resistor R2 are connected together as the first terminal of the lower half-bridge absorption circuit, which is connected to the negative terminal DC- of the DC voltage. The other end of the second suppression reactor L2 and the negative terminal of the second absorption diode D8 are connected together as the second terminal of the lower half-bridge absorption circuit, which is connected to one end of the half-bridge circuit. The other end of the second suppression resistor and the positive terminal of the second absorption diode are connected to one end of the second absorption capacitor C2. The other end of the second absorption capacitor serves as the third terminal of the lower half-bridge absorption circuit, which is connected to the third terminal of the upper half-bridge absorption circuit and to the first terminal NP of the half-bridge circuit.

[0058] The half-bridge circuit includes four IGCT devices connected in sequence, four freewheeling diodes connected in sequence, and two clamping diodes connected in sequence. The anode of the first IGCT V1 and the cathode of the first freewheeling diode D1 are connected to the second terminal of the upper half-bridge absorption circuit. The cathode of the first IGCT V1, the anode of the first freewheeling diode D1, the anode of the second IGCT V2, and the cathode of the second freewheeling diode D2 are connected to the cathode of the first clamping diode D5. The cathode of the second IGCT V2, the anode of the second freewheeling diode D2, the anode of the third IGCT V3, and the third freewheeling diode D5 are connected to the second freewheeling diode D5. The negative terminals of diodes D3 are connected together and serve as the output terminal NP of the half-bridge circuit. The negative terminal of the third IGCT transistor V3, the positive terminal of the third freewheeling diode D3, the positive terminal of the fourth IGCT transistor V4, and the negative terminal of the fourth freewheeling diode D4 are connected to the positive terminal of the second clamping diode D6. The negative terminal of the fourth IGCT transistor V4 and the positive terminal of the fourth freewheeling diode D4 are connected to the second terminal of the lower half-bridge absorption circuit. The positive terminal of the first clamping diode D5 and the negative terminal of the second clamping diode D6 are connected to the output terminal NP of the half-bridge circuit. The control terminals of the four IGCT devices are respectively connected to the control circuit.

[0059] When the IGCT power module and the snubber diode are working normally, the current on the suppressor is a periodic signal, and a corresponding periodic voltage signal is generated across the suppressor. When the IGCT power module is working normally but the snubber diode fails, there is no current signal on the suppressor and no voltage across the suppressor. What is detected is a long zero signal. The failure of the snubber diode will not immediately lead to converter failure, but it will eventually lead to converter failure. Timely identification of the failure of the snubber diode D7 or D8 can be dealt with in a timely manner to prevent the fault from escalating further.

[0060] The detection module includes a current detection circuit for detecting the current signal in the suppression reactor. This circuit includes a current sensing unit and a signal processing unit. The signal processing unit comprises a sensing subunit, a first voltage divider subunit, and a voltage regulator subunit connected in sequence. Figure 3 As shown, the current sensing unit includes a secondary coil. A secondary coil is provided on each suppression reactor for sensing the voltage signal on the suppression reactor. The secondary coil is insulated from the suppression reactor. The two ends of the secondary coil are connected to the first voltage divider unit. The secondary coil senses the voltage of the suppression reactor to obtain an induced voltage signal.

[0061] The equivalent circuit of the suppression reactor and secondary coil is as follows: Figure 4As shown, the suppression reactor and the secondary coil are equivalent to a high-ratio air-core transformer. The suppression reactor is equivalent to the primary side of the transformer, and the secondary coil is equivalent to the secondary side of the transformer. By adjusting the turns ratio of the primary and secondary sides, the voltage generated by the large current flowing through the primary side can induce a smaller voltage on the secondary side.

[0062] The first voltage divider unit divides the induced voltage signal of the secondary coil to obtain a first voltage divider signal. The voltage regulator unit regulates the first voltage divider signal. The first voltage divider unit divides the induced voltage signal, and the voltage regulator unit regulates the voltage division result to obtain a stable voltage signal. The voltage regulator unit directly transmits the stable voltage signal to the control module.

[0063] The signal processing unit also includes a signal transmitting subunit, a sensing subunit, a first voltage divider subunit, a voltage stabilizing subunit, and a signal transmitting subunit connected in sequence. The sensing subunit senses the current signal in the suppression reactor to obtain an induced voltage signal. The first voltage divider subunit divides the induced voltage signal, and the voltage stabilizing subunit stabilizes the voltage division result to obtain a stable voltage signal. The signal transmitting subunit converts the stable voltage signal to obtain an optical signal or an electrical signal, and transmits the converted electrical signal or optical signal to the control module.

[0064] When the IGCT power module is working, a periodic large current flows through the suppression reactors L1 and L2, generating a periodic voltage signal across the suppression reactors. This periodic voltage signal is induced in the secondary coil. When the absorption diodes D7 and / or D8 are working normally, a periodic voltage signal is induced in the secondary coil, and the module is in an effective state. If the absorption diodes D7 and / or D8 are not working properly, no current flows through the suppression reactors in the malfunctioning half-bridge absorption circuit, resulting in no voltage across the suppression reactors. The secondary coil does not induce a voltage signal for a certain period, and therefore, there is no induced voltage signal across its terminals. The output is a zero signal exceeding the set duration, and the module is in an ineffective state.

[0065] By setting a secondary coil on the suppressor, the current signal on the suppressor can be detected in a timely manner. Furthermore, the secondary coil is insulated from the suppressor and will not affect the IGCT power module, thus reducing the probability of converter damage caused by the failure of the absorption diode in the IGCT power module.

[0066] After the converter bus voltage is within the normal voltage range and the converter control center sends a pulse start signal to the IGCT power module, the control module sends a detection command signal to the detection circuit. When the control module receives a zero signal that exceeds the set duration, it determines that the resistive reactor has failed according to the judgment conditions. When it receives a periodic signal, it determines that the resistive reactor is normal.

[0067] In one specific embodiment of this application, the failure detection circuit is as follows: Figure 5 As shown, a secondary coil is set on one side of the suppression reactor L1 to sense the current in the suppression reactor L1 and obtain an induced voltage signal. The induced voltage signal is transmitted to the first signal processing unit. The first signal processing unit performs voltage division and voltage stabilization on the induced voltage signal to obtain a voltage signal, which is sent to the control module. The control module determines whether the suppression reactor has failed based on the received voltage signal and the judgment conditions. When the received signal is a periodic signal, the suppression reactor is judged to be normal. When the received signal is a zero signal that exceeds the set duration, the suppression reactor is judged to have failed. When the suppression reactor fails, the control module issues an alarm and performs corresponding control operations.

[0068] Similarly, a secondary coil is also set on one side of the suppression reactor L2 to sense the current in the suppression reactor L2 and obtain an induced voltage signal. The induced voltage signal is transmitted to the second signal processing unit. The second signal processing unit performs voltage division and voltage regulation on the induced voltage signal to obtain a voltage signal, which is sent to the control module. The control module determines whether the suppression reactor has failed based on the received voltage signal and the judgment conditions. When the received signal is a periodic signal, the suppression reactor is judged to be normal. When the received signal is a zero signal that exceeds the set duration, the suppression reactor is judged to have failed. When the suppression reactor fails, the control module issues an alarm and performs corresponding control operations.

[0069] The first signal processing unit and the second signal processing unit have the same structure. For ease of description, they are referred to as signal processing units in this application, which correspond to the first signal processing unit and the second signal processing unit respectively.

[0070] The detection module also includes a startup detection circuit for detecting the startup status of the IGCT power module.

[0071] The startup detection circuit includes a bus voltage detection unit and a pulse startup detection unit.

[0072] The bus voltage detection unit is used to detect the bus voltage of the converter where the IGCT power module is located. It performs voltage division and amplification on the detected bus voltage signal to obtain an amplified signal, which is then transmitted to the control module.

[0073] Bus voltage detection unit, such as Figure 6 As shown, it includes a second voltage divider subunit, an amplification subunit, and a communication subunit connected in sequence. The second voltage divider subunit is used to divide the acquired bus voltage to obtain a second voltage divider signal. The amplification subunit amplifies the second voltage divider signal to obtain an amplified signal. The communication subunit transmits the amplified signal to the control module.

[0074] Specifically, the first voltage divider unit and the second voltage divider unit each include a series resistor combination for voltage division.

[0075] The amplification subunit includes a differential amplifier circuit for amplifying signals.

[0076] The voltage regulator subunit includes a voltage regulator circuit for voltage regulation of signals.

[0077] The control module determines whether the bus voltage is within the normal operating voltage range based on the amplified signal from the bus voltage detection unit.

[0078] The system judges the detected bus voltage. When the bus voltage rises to the normal operating voltage range, it is determined that the bus is within the normal operating voltage range and a normal bus voltage signal is output. When the detected bus voltage is not within the normal operating voltage range, an abnormal bus voltage signal is output.

[0079] The pulse start detection circuit detects the pulse start signal output by the converter to the IGCT power module and transmits the detection result of the pulse start signal to the control module. The control module determines whether the IGCT power module has started based on the pulse start signal.

[0080] According to the startup sequence of starting the low-voltage circuit first and then the high-voltage circuit, the IGCT power module has already started before there is voltage on the converter bus. After receiving the amplified signal of the bus voltage and the pulse start signal of the IGCT power module, the control module determines that the converter is working and the IGCT power module has started working. Then, based on the voltage signal received from the current detection circuit, it determines whether the absorption diode has failed. Based on the determination result, it outputs a control signal to the IGCT power transistor in the IGCT power module to control the working state of the IGCT power module.

[0081] By detecting the converter bus voltage and pulse start signal, the authenticity of the current detection circuit output signal is ensured, reducing the probability of the control module generating a false alarm based on the non-working signal output by the current detection circuit when the converter starts up but the IGCT power module has not yet started working.

[0082] The detection module includes a drive control unit (DCU).

[0083] In one specific embodiment of this application, the signal transmission subunit includes an electro-optic signal conversion sub-circuit, used to convert the regulated signal into an optical signal, and then transmit the optical signal to the control module for judgment.

[0084] In another specific embodiment of this application, the signal transmitting subunit includes a signal transmission subcircuit that transmits the regulated signal to the control module for judgment.

[0085] In another specific embodiment of this application, the signal transmitting subunit includes a light-emitting sub-circuit for emitting light according to the output signal of the voltage regulator subunit, and the controller determines whether the absorption diode is working properly based on the light-emitting signal.

[0086] In one specific embodiment of this application, the detection module includes a current sensor circuit, a first voltage divider subunit, and a voltage regulator subunit connected in sequence. The current sensor circuit is used to detect the magnitude of the current in the suppression reactor and obtain an induced voltage signal. The first voltage divider subunit performs voltage division processing on the induced voltage signal of the current sensor circuit to obtain a voltage divider signal. The voltage regulator subunit performs voltage regulation processing on the voltage divider signal to obtain a regulated signal. The regulated signal is then transmitted to the control module for judgment.

[0087] The detection module also includes a signal transmission subunit, which converts the regulated signal into a first signal and transmits it to the control module. The first signal may be an optical signal or an electrical signal.

[0088] This application discloses a method for detecting the failure of an absorption diode in an IGCT power module. The suppression reactor and the absorption diode in the IGCT power module are located in the absorption circuit. The method includes detecting the current signal of the suppression reactor in the IGCT power module to obtain an induced voltage signal; performing amplitude and voltage regulation processing on the induced voltage signal to obtain a voltage signal; determining whether the absorption diode has failed based on the voltage signal; and controlling the operating state of each IGCT device in the IGCT power module based on the determination result.

[0089] If the voltage signal is zero for a duration exceeding a set time, the absorption diode is determined to be faulty, and all IGCT power transistors in the IGCT power module are turned off and stopped working. If the voltage signal is periodic, the absorption diode is determined to be normal, and all IGCT power transistors in the IGCT power module are controlled to work normally.

[0090] This application discloses a method for detecting the failure of an absorption diode in an IGCT power module. The method includes detecting the bus voltage of the converter where the IGCT power module is located, processing the bus voltage detection signal to obtain a second signal of the converter bus voltage, determining whether the bus voltage is within the normal operating voltage range based on the second signal, acquiring the pulse start signal of the converter for the IGCT power module when the bus voltage is within the normal operating voltage range, detecting the current in the suppression reactor of the IGCT power module after confirming that the bus voltage is normal and the IGCT power module is started, detecting the current in the suppression reactor of the IGCT power module to obtain an induced voltage signal, processing the amplitude of the detected induced voltage signal to obtain a voltage signal for detecting the current in the suppression reactor, judging the voltage signal according to judgment conditions, determining that the absorption diode is working normally when the voltage signal is a periodic signal, determining that the absorption diode is failing when the first signal is a zero signal with a duration exceeding a set time, controlling each IGCT power transistor in the IGCT power module to turn off and stop working when the absorption diode is failing, and continuing detection when the absorption diode is normal to control each IGCT power transistor in the IGCT power module to work normally.

[0091] Specifically, it includes the following steps:

[0092] S1, Begin;

[0093] S2. Detect the converter bus voltage, and perform amplitude and amplification processing on the detection result to obtain the second signal;

[0094] S3. Based on the second signal, determine whether the bus voltage is within the normal operating range. If yes, proceed to the next step; otherwise, go to S2.

[0095] S4. The pulse start signal sent by the detection control module to the IGCT power module;

[0096] S5. Based on the detection result of the pulse start signal, determine whether the IGCT power module has started. If yes, proceed to the next step; otherwise, go to S4.

[0097] S6. Detect the current in the suppression reactor in the IGCT power module to obtain the induced voltage signal, and perform amplitude processing to obtain the voltage signal of the current detection circuit.

[0098] S7. Based on the voltage signal, determine whether the absorption diode has failed. If not, proceed to the next step; if yes, go to S9.

[0099] S8. Control each IGCT power transistor in the IGCT power module to work normally, then proceed to S2;

[0100] S9. Issue an alarm signal;

[0101] S2, End.

[0102] This application discloses a failure detection device for the absorption diode in an IGCT power module, comprising a detection module and a control module. The detection module detects the voltage on the converter bus, the pulse start signal from the control module for the IGCT power module, and the current on the suppression reactor, and transmits the detection results to the control module. The control module determines whether the converter is operating normally based on the voltage on the converter bus. After normal operation, it determines whether the IGCT power module is started based on the pulse start signal. When the converter is operating normally and the IGCT power module is started, it detects the current signal on the suppression reactor to obtain a voltage signal. Based on the voltage signal, it determines whether the absorption diode has failed. When the voltage signal is periodic, it indicates that the absorption diode is working normally, and the IGCT power module is controlled to operate normally. If the voltage signal is a zero signal exceeding a set duration, it is determined that the absorption diode has failed, and an alarm is issued.

[0103] The detection module includes a current detection circuit and a start-up detection circuit. The current detection circuit is used to detect the magnitude of the current on the suppression reactor and output a voltage signal. The start-up detection circuit includes a bus voltage detection unit and a pulse start-up detection unit. The bus voltage detection unit is used to detect the magnitude of the bus voltage, and the pulse start-up detection unit is used to detect the pulse start-up signal.

[0104] The control module includes a memory and a processor, which is used to receive the output signals from the detection module, including the bus voltage magnitude, pulse start signal and voltage signal, and determine whether the absorption diode has failed based on the received signals.

[0105] An embodiment of the present invention provides a failure detection terminal device for the absorption diode in an IGCT power module. The terminal device of this embodiment includes: a processor, a memory, and a computer program stored in the memory and executable on the processor, such as a failure judgment program. When the processor executes the computer program, it implements the judgment steps described in this application.

[0106] For example, the computer program may be divided into one or more modules / units, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units may be a series of computer program instruction segments capable of performing specific functions, which describe the execution process of the computer program in the failure detection terminal device for the absorption diode in the IGCT power module.

[0107] The failure detection terminal device for the absorption diode in the IGCT power module can be a computing device such as a desktop computer, laptop, handheld computer, or cloud server. The failure detection terminal device for the absorption diode in the IGCT power module may include, but is not limited to, a processor and memory. Those skilled in the art will understand that the above examples are merely examples of failure detection terminal devices for the absorption diode in the IGCT power module and do not constitute a limitation on the failure detection terminal device for the absorption diode in the IGCT power module. It may include more or fewer components than illustrated, or combine certain components, or different components. For example, the failure detection terminal device for the absorption diode in the IGCT power module may also include input / output devices, network access devices, buses, etc.

[0108] The processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), or application-specific integrated circuits (ASICs).

[0109] Application Specific Integrated Circuit (ASIC), Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc. This processor is the control center of the terminal device, connecting various parts of the IGCT power module's absorption diode failure detection terminal device via various interfaces and lines.

[0110] The memory can be used to store the computer program and / or modules. The processor, by running or executing the computer program and / or modules stored in the memory and calling the data stored in the memory, realizes various functions of the failure detection terminal device for the absorption diode in the IGCT power module. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created according to the use of the mobile phone (such as audio data, phonebook, etc.). In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital card (SD) card, flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0111] If the module / unit integrated into the failure detection terminal device for the absorption diode in the aforementioned IGCT power module is implemented as 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, all or part of the processes in the methods of the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content contained in the computer-readable medium may be appropriately added to or subtracted from the content as required by the legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium may not include electrical carrier signals and telecommunication signals.

[0112] In one embodiment, the at least one computer-executable instruction may also be compiled into or comprise a software product / computer program product, wherein one or more computer-executable instructions are executed by a processor to perform the steps of the various functions and / or methods in the embodiments described herein.

[0113] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A failure detection circuit for the absorption diode in an IGCT power module, characterized in that, include: Detection module and control module; The detection module is used to detect the current signal of the suppression reactor in the IGCT power module, obtain the voltage signal, and transmit the detected voltage signal to the control module. The suppression reactor and the absorption diode are located together in the absorption circuit of the IGCT power module. The control module is used to determine whether the absorption diode has failed based on the voltage signal detected by the detection module, and to output a control signal to the IGCT power module based on the determination result, so as to control the working state of each IGCT device in the IGCT power module.

2. The failure detection circuit for the absorption diode in the IGCT power module according to claim 1, characterized in that, The detection module includes a start-up detection circuit and a current detection circuit. The startup detection circuit is used to detect the bus voltage signal of the converter where the IGCT power module is located and the pulse startup signal output by the converter for the IGCT power module, and transmit the detected signals to the control module. The current detection circuit is used to receive the detection command signal issued by the control module, detect the current signal flowing through the suppression reactor according to the detection command signal, and transmit the detected voltage signal to the control module; the detection command is generated by the control module based on the bus voltage signal and the pulse start signal.

3. The failure detection circuit for the absorption diode in the IGCT power module according to claim 2, characterized in that, The current detection circuit includes: a current sensing unit and a signal processing unit connected in sequence; The current sensing unit is used to sense the current signal in the suppression reactor and obtain the induced voltage signal; The signal processing unit is used to perform amplitude conversion on the sensed voltage signal to obtain a voltage signal, and transmit the voltage signal to the control module; The control module determines whether the absorption diode has failed based on the voltage signal received from the signal processing unit, and outputs a control signal to the IGCT power module according to the determination result, so as to control the working state of each IGCT device in the IGCT power module.

4. The failure detection circuit for the absorption diode in the IGCT power module according to claim 3, characterized in that, The current sensing unit includes a secondary coil, which is used to form an air-core transformer with the suppression reactor. Current flows through the suppression reactor. When there is a voltage across the suppression reactor, the secondary coil generates an induced voltage signal that is proportional to the voltage across the suppression reactor. The signal processing unit is used to perform amplitude conversion processing on the induced voltage signal to obtain a voltage signal, and then transmit the obtained voltage signal to the control module.

5. The failure detection circuit for the absorption diode in the IGCT power module according to claim 4, characterized in that, The signal processing unit includes a first voltage divider subunit and a voltage regulator subunit connected in sequence. The first voltage divider subunit is used to divide the voltage signal in the secondary coil to generate a voltage divider signal; The voltage regulator subunit is used to regulate the voltage divider signal and transmit the resulting regulated signal as the voltage signal to the control module.

6. The failure detection circuit for the absorption diode in the IGCT power module according to claim 5, characterized in that, The signal processing unit further includes: The signal transmitting subunit is used to convert the regulated signal into a first light-emitting signal and transmit the first light-emitting signal to the control module; The control module determines whether the absorption diode is faulty based on the first light emission signal received from the signal transmission subunit, and outputs a control signal to the IGCT power module according to the determination result, so as to control the working state of each IGCT device in the IGCT power module.

7. The failure detection circuit for the absorption diode in the IGCT power module according to claim 2, characterized in that, The startup detection circuit includes: a bus voltage detection unit and a pulse startup detection unit; The bus voltage detection unit is used to detect the bus voltage signal of the converter where the IGCT power module is located, and transmit the bus voltage signal to the control module. The pulse start detection unit is used to detect the pulse start signal of the converter for the IGCT power module and transmit the pulse start signal to the control module. The control module is used to generate the detection command signal and send it to the current detection circuit when the bus voltage signal indicates that the bus voltage is within the normal operating range and the pulse start signal indicates that the IGCT power module is in normal operating condition.

8. A method for detecting the failure of an absorption diode in an IGCT power module, characterized in that, include: The current signal of the suppression reactor in the IGCT power module is detected to obtain the voltage signal; the suppression reactor and the absorption diode are located together in the absorption circuit of the IGCT power module. Based on the voltage signal, it is determined whether the absorption diode has failed, and the working state of each IGCT device in the IGCT power module is controlled according to the determination result.

9. The failure detection method for the absorption diode in the IGCT power module according to claim 8, characterized in that, Before detecting the current signal of the suppression reactor in the IGCT power module, the method further includes: The bus voltage signal of the converter where the IGCT power module is located and the pulse start signal output by the converter for the IGCT power module are detected. When it is determined that the bus voltage signal indicates that the bus voltage is within the normal operating range, and the pulse start signal indicates that the IGCT power module is in normal operating condition, the step of detecting the current signal of the suppression reactor in the IGCT power module is executed.

10. The failure detection method for the absorption diode in the IGCT power module according to claim 8, characterized in that, The step of determining whether the absorption diode has failed based on the voltage signal, and controlling the operating state of each IGCT device in the IGCT power module based on the determination result, includes: If the voltage signal is periodic, and the duration of the zero voltage signal exceeds a set time, the absorption diode is determined to be faulty; otherwise, the absorption diode is determined to be normal.

11. A computer device, comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the method of any one of claims 8-9.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method described in any one of claims 8-9.

13. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the method described in any one of claims 8-9.

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