Converter power device dynamic and static fault detection system and method

Abstract

The application provides a kind of converter power device static and dynamic fault detection system and method.Control unit static fault detection module receives the pulse generation state signal generated by drive pulse generation module, and collector-emitter voltage signal and support capacitor voltage Udc signal, whether converter power device exists static fault is judged;Dynamic fault detection module: receive the pulse generation state signal generated by drive pulse generation module, and collector-emitter voltage signal, whether converter power device exists dynamic fault is judged.The application executes converter power device static and dynamic fault detection function by control unit, detects the whole closed path of power device drive signal and drive feedback signal, can execute the protection action of blocking pulse trigger when there is dynamic fault or static fault.The detection function is independent of the fault detection mechanism of drive board itself, as the supplement of drive board itself detection.

Description

Technical Field

[0001] This invention belongs to the field of power electronics technology, and in particular relates to a dynamic and static fault detection system and method for converter power devices. Background Technology

[0002] Power electronic converters mainly consist of a control unit and the main circuit. Power devices (specifically, the commonly used fully controlled IGBTs) are a crucial component of the main circuit. These power devices are key components for energy conversion in power electronic converters. Drive signals control their switching on and off actions. Large voltage and current fluctuations occur during these processes, making the detection and protection of power devices extremely important. Existing power device detection and protection mechanisms primarily consist of two parts: first, the control unit collects analog signals from the main circuit related to the power device and performs rapid overvoltage and overcurrent fault diagnosis; second, the power device's own drive circuit board diagnoses and protects against faults related to the device's switching characteristics.

[0003] Existing power device drive fault detection technologies rely excessively on the self-detection function of the drive circuit board. The control unit generally directly receives the power device drive fault signal fed back by the drive circuit board, and the detection of possible fault problems in the transmission path of the drive signal and the fault feedback signal is not comprehensive. Summary of the Invention

[0004] The purpose of this invention is to solve one of the aforementioned technical problems and provide a converter power device dynamic and static fault detection system and method that does not rely on a drive circuit board, enabling rapid detection of power device faults.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A dynamic and static fault detection system for power devices in a converter, wherein the converter includes a control unit, a main circuit power device unit, and a DC-side support capacitor, wherein the DC-side support capacitor is connected in parallel with the main circuit power device unit;

[0007] The control unit includes: a drive pulse generation module, used to send pulse drive signals to the main circuit power device unit and generate pulse generation status signals;

[0008] The converter further includes: an analog signal acquisition component for acquiring the DC support capacitor voltage Udc; a signal feedback component for acquiring the collector-emitter voltage of the power device; and a drive component for receiving pulse drive signals and transmitting them to the power device.

[0009] The control unit further includes:

[0010] Static fault detection module: Receives pulse generation status signals generated by the drive pulse generation module, as well as collector-emitter voltage signals and supporting capacitor voltage Udc signals, to determine whether there are static faults in the converter power devices;

[0011] Dynamic fault detection module: Receives the pulse generation status signal generated by the drive pulse generation module and the collector-emitter voltage signal to determine whether there is a dynamic fault in the power device of the converter.

[0012] In some embodiments of the present invention, the control unit further includes a computing unit: for receiving static fault detection signals from a static fault detection module and dynamic fault detection signals from a dynamic fault detection module;

[0013] The arithmetic unit outputs a drive pulse start / stop signal to the drive pulse generation module to control the drive pulse generation module to output a pulse drive signal to the main circuit power unit. When the arithmetic unit detects a static fault signal or a dynamic fault signal, it outputs an output pulse stop signal to the drive pulse generation module.

[0014] In some embodiments of the present invention, a method for detecting dynamic and static faults in converter power devices is further provided, comprising the following steps:

[0015] Determine the state of the drive pulse enable signal; if it is 1, perform dynamic fault detection; if it is 0, perform static fault detection.

[0016] Dynamic fault detection methods include:

[0017] The collector-emitter voltage signal Vce is detected, and the presence of a dynamic fault is determined based on the pulse drive signal and the collector-emitter voltage signal.

[0018] Static fault detection methods include:

[0019] Detect the collector-emitter voltage signal Vce and the DC support capacitor voltage Udc signal to determine if there is a static fault.

[0020] In some embodiments of the present invention, during dynamic fault detection and static fault detection, the collector-emitter voltage signal Vce is detected and converted into an output feedback signal to determine whether a dynamic or static fault exists; the method for converting the collector-emitter voltage signal Vce into an output feedback signal includes:

[0021] Set the first comparison threshold U_up for the feedback voltage and the second comparison threshold U_low for the feedback voltage;

[0022] If the collector-emitter voltage signal Vce is greater than the first comparison threshold U_up of the feedback voltage, then the feedback signal 1 is output.

[0023] If the collector-emitter voltage signal Vce is less than the second comparison threshold U_low of the feedback voltage, then the output feedback signal is 0.

[0024] In some embodiments of the present invention, the dynamic fault detection method further includes:

[0025] When the drive pulse signal is 1, and the output feedback signal is 1;

[0026] or,

[0027] When the drive pulse signal is 0, and the output feedback signal is 0;

[0028] Then a dynamic fault is determined to exist.

[0029] In some embodiments of the present invention, the dynamic fault detection method further includes:

[0030] When the drive pulse signal is 1, and the output feedback signal is 1, and the duration exceeds t2;

[0031] or,

[0032] When the drive pulse signal is 0, and the output feedback signal is 0, and the duration exceeds t2;

[0033] Then a dynamic fault is determined to exist.

[0034] In some embodiments of the present invention, the static fault detection method further includes:

[0035] Set the first static fault voltage threshold Uth_1 and the second static fault voltage threshold Uth_2;

[0036] If the DC support capacitor voltage Udc signal is less than the first static fault voltage threshold Uth_1, output feedback signal 1;

[0037] or,

[0038] When the DC support capacitor voltage Udc signal is greater than the second static fault voltage threshold Uth_2, the output feedback signal is 0.

[0039] Then a static fault is determined to exist.

[0040] In some embodiments of the present invention, the static fault detection method further includes:

[0041] If the DC support capacitor voltage Udc signal is less than the first static fault voltage threshold Uth_1, the output feedback signal 1 is fed back, and the duration is greater than t1;

[0042] or,

[0043] When the DC support capacitor voltage Udc signal is greater than the second static fault voltage threshold Uth_2, the output feedback signal is 0, and the duration is greater than t1.

[0044] Then a static fault is determined to exist.

[0045] In some embodiments of the present invention, when a dynamic or static fault occurs, the transmission of drive signals to the converter power devices is stopped.

[0046] The converter power device dynamic and static fault detection system and method provided by this invention have the following advantages:

[0047] 1. The control unit performs dynamic and static fault detection functions for the converter power devices, detecting the entire closed-loop path of the power device drive signals and drive feedback signals. It can execute a protection action triggered by a blocking pulse in the event of a dynamic or static fault. This detection function is independent of the drive board's own fault detection mechanism and serves as a supplement to the drive board's own detection.

[0048] 2. It can simultaneously perform dynamic and static fault detection, with dynamic detection including both turn-on and turn-off processes. The protection mechanism for power devices is comprehensive, covering all operating states of the power devices.

[0049] 3. The dynamic and static drive fault detection mechanism described in this invention fully considers the characteristics of the power devices themselves and the operating state characteristics of the converter main circuit, and the judgment mechanism is stable and reliable. Attached Figure Description

[0050] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0051] Figure 1 This is a schematic diagram of the overall structure of the converter;

[0052] Figure 2 This is a schematic diagram of the dynamic and static fault detection system for a converter.

[0053] Figure 3 This is a schematic diagram of the main circuit structure of the converter;

[0054] Figure 4 This is a schematic diagram of the logic structure of the converter control unit;

[0055] Figure 5 This is a flowchart of the steps for detecting dynamic and static drive faults.

[0056] Figure 6 This is a graph showing the relative relationship between the pulse drive signal and the feedback signal from the power device.

[0057] Figure 7 This is a schematic diagram of the uncontrolled rectification operation. Detailed Implementation

[0058] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0059] refer to Figure 1 The structure of a converter includes a control unit, a main circuit power device unit, a DC link, and a converter.

[0060] Reference Figure 2 and Figure 3 The main circuit power device unit is a bridge circuit composed of power devices. These power devices are the main components of the converter's power conversion and also the objects being driven, detected, and protected. Each power device is connected to a drive unit. Each drive unit includes a drive component, a signal feedback component, and an isolation component. The drive component receives the drive signal from the control unit, provides the gate drive signal to the power device, and acquires its collector-emitter voltage Vce. After processing Vce, it transmits the feedback signal to the control unit. Simultaneously, the drive component also converts the drive signal output from the control unit into the gate-emitter control voltage signal Vge of the power device. The signal feedback component converts the collector-emitter voltage Vce of the power device into a feedback signal and feeds it back to the control unit. The isolation component provides electrical isolation.

[0061] The DC link includes DC-side support capacitors, which are energy storage elements connected in parallel across the power device units in the main circuit to provide power to the bridge circuit composed of power devices.

[0062] The analog signal acquisition unit is responsible for acquiring the DC voltage signal Udc of the DC link support capacitor and transmitting the signal to the control unit.

[0063] In addition to the above structures, the main circuit components of the converter are other components that realize the functions of the main circuit of the converter, such as stacked busbars and structural components. They are not related to drive fault detection and will not be described in detail.

[0064] Unlike existing technologies, the dynamic and static fault detection of the converter in this patent is accomplished through a control circuit.

[0065] refer to Figure 4The control unit includes a logic and algorithm operation unit, a drive pulse control unit, and a signal conversion interface unit. The logic and algorithm operation unit is usually implemented by a DSP chip, the drive pulse control unit is implemented by an FPGA, and the signal conversion interface unit is an interface circuit board that implements level conversion.

[0066] In order to enable the detection of dynamic and static faults in the converter, the function of the control unit is improved in this invention.

[0067] refer to Figure 4 The control unit includes a drive pulse generation module, which is used to send pulse drive signals to the main circuit power device unit and generate a pulse generation status signal; wherein, the pulse drive signal is used to drive the operation of the power device, and the pulse generation status signal is used to reflect whether the pulse generation module is issuing pulse drive signals in a normal state.

[0068] The control unit further includes:

[0069] Static fault detection module: Receives pulse generation status signals generated by the drive pulse generation module, as well as collector-emitter voltage signals and supporting capacitor voltage Udc signals, to determine whether there are static faults in the converter power devices;

[0070] Dynamic fault detection module: Receives the pulse generation status signal generated by the drive pulse generation module and the collector-emitter voltage signal to determine whether there is a dynamic fault in the power device of the converter.

[0071] In this embodiment, both the static fault detection module and the dynamic fault detection module are functional units integrated into the drive pulse generation module, and the fault detection function is performed by the drive pulse generation module.

[0072] In some embodiments of the present invention, the control unit further includes a computing unit: for receiving static fault detection signals from a static fault detection module and dynamic fault detection signals from a dynamic fault detection module;

[0073] The logic and algorithm operation unit outputs a drive pulse start / stop signal to the drive pulse generation module to control the drive pulse generation module to output a pulse drive signal to the main circuit power unit. When the operation unit detects a static fault signal or a dynamic fault signal, it outputs an output pulse stop signal to the drive pulse generation module.

[0074] Specifically, the drive pulse control unit implements drive pulse generation, static drive fault detection, and dynamic drive fault detection functions. The drive pulse generation module receives drive pulse start / stop signals and pulse width control signals from the logic and algorithm unit, performs PWM pulse modulation generation, and outputs the drive signal PS. 1-nThe drive pulse generation module directly receives the fast protection command FP_cmd from the static drive fault detection and dynamic drive fault detection modules. When a dynamic or static drive fault is detected, the pulse is quickly blocked. Additionally, the drive pulse generation module records the drive pulse generation status PL_st and the various drive signals PS. 1-n The data is transmitted to the dynamic and static driver fault detection module for use in driver fault detection.

[0075] In some embodiments of the present invention, the drive pulse generation module is equipped with a DC bus voltage undervoltage protection function. When the detected DC voltage signal Udc is less than the converter undervoltage threshold Udc_min, the switch drive pulse is blocked. The converter undervoltage threshold Udc_min is determined by the converter's inherent performance and satisfies Formula 1. Therefore, when the switch pulse is enabled, the DC voltage Udc is always greater than twice the hysteresis comparison upper limit threshold U_up. When the power device is not turned on, the collector-emitter voltage Vce is either Udc or 0.5*Udc, and Vce is always greater than the hysteresis comparison upper limit threshold U_up of the signal feedback component. Thus, in dynamic drive fault detection, only the switch pulse enable signal PL_st and the comparison relationship between the drive signal and the feedback signal are considered; there is no need to determine the DC voltage signal amplitude.

[0076] Udc_min>2×U_up (Formula 1)

[0077] Based on the foregoing principles, some embodiments of the present invention further provide a method for detecting dynamic and static faults in converter power devices, referencing... Figure 5 Specifically, it includes the following steps.

[0078] Determine the state of the drive pulse enable signal; if it is 1, perform dynamic fault detection; if it is 0, perform static fault detection.

[0079] Dynamic fault detection methods include:

[0080] The collector-emitter voltage signal Vce is detected, and the presence of a dynamic fault is determined based on the pulse drive signal and the collector-emitter voltage signal.

[0081] Static fault detection methods include:

[0082] Detect the collector-emitter voltage signal Vce and the DC support capacitor voltage Udc signal to determine if there is a static fault.

[0083] The drive pulse enable signal PL_st is a comprehensive judgment result. In simple terms, it means that the drive pulse generation unit can normally issue pulse drive signals and drive the power components normally. Specifically, positively, when the drive pulse start / stop signal is 1 (pulse command issued), the fast protection command FP_cmd is 0 (no drive fault occurred), and there are no other analog protection faults or other faults, PL_st is 1 (pulse issuance state). Conversely, from the result perspective, PL_st being 1 (pulse issuance state) means that at least one output drive signal PS1-n is 1 (power device enabled).

[0084] In some embodiments of the present invention, during dynamic fault detection and static fault detection, the collector-emitter voltage signal Vce is detected and converted into an output feedback signal to determine whether a dynamic or static fault exists; the method for converting the collector-emitter voltage signal Vce into an output feedback signal includes:

[0085] Set the first comparison threshold U_up for the feedback voltage and the second comparison threshold U_low for the feedback voltage;

[0086] If the collector-emitter voltage signal Vce is greater than the first comparison threshold U_up of the feedback voltage, then the feedback signal FB is output. 1-n Feedback 1;

[0087] If the collector-emitter voltage signal Vce is less than the second comparison threshold U_low of the feedback voltage, then the feedback signal FB is output. 1-n Feedback: 0.

[0088] Specifically, the signal feedback component acquires the collector-emitter voltage Vce of the power device and performs a hysteresis comparison operation on Vce. Specifically, if Vce is greater than the threshold U_up, the feedback signal FB is generated. 1-n Set to 1, which is a high level; if Vce is less than the threshold U_low, then the feedback signal FB is activated. 1-n Set to 0 for low level; if Vce is between the two thresholds U_up and U_low, maintain the original level (U_up > U_low). The use of hysteresis comparison enhances the signal processing's anti-interference capability.

[0089] Combined with the output feedback signal FB 1-n In some embodiments of the invention, the dynamic fault detection method further includes:

[0090] When the drive pulse signal PS 1-n The value is 1, and the output feedback signal FB is 1. 1-n Feedback 1;

[0091] or,

[0092] When the drive pulse signal PS 1-n The value is 0, and the output feedback signal FB is 0. 1-n Feedback: 0;

[0093] Then a dynamic fault is determined to exist.

[0094] Furthermore, in some embodiments of the present invention, the dynamic fault detection method further includes:

[0095] When the drive pulse signal is 1, and the output feedback signal is 1, and the duration exceeds t2;

[0096] or,

[0097] When the drive pulse signal is 0, and the output feedback signal is 0, and the duration exceeds t2;

[0098] Then it is determined that a dynamic fault exists, and the dynamic fault feedback signal DF is generated. 1-n The output is 1.

[0099] refer to Figure 6 Considering the turn-on delay t of the power device IGBT during the turn-on or turn-off process on and shutdown delay t off And drive signal PS 1-n and feedback signal FB 1-n The transmission has a transmission delay time t d Therefore, the dynamic drive fault detection duration t2 should satisfy the following formula.

[0100]

[0101] In some embodiments of the present invention, the static fault detection method further includes:

[0102] Set the first static fault voltage threshold Uth_1 and the second static fault voltage threshold Uth_2;

[0103] If the DC support capacitor voltage Udc signal is less than the first static fault voltage threshold Uth_1, output feedback signal 1;

[0104] or,

[0105] When the DC support capacitor voltage Udc signal is greater than the second static fault voltage threshold Uth_2, the output feedback signal is 0.

[0106] Then a static fault is determined to exist. At this time, the static fault signal SF... 1-n The feedback was 1.

[0107] In some embodiments of the present invention, the static fault detection method further includes:

[0108] If the DC support capacitor voltage Udc signal is less than the first static fault voltage threshold Uth_1, the output feedback signal 1 is fed back, and the duration is greater than t1;

[0109] or,

[0110] When the DC support capacitor voltage Udc signal is greater than the second static fault voltage threshold Uth_2, the output feedback signal is 0, and the duration is greater than t1.

[0111] Then a static fault is determined to exist. At this time, the static fault signal SF... 1-n The feedback was 1.

[0112] When the switch pulse enable signal PL_st = 0, the DC voltage Udc is normally shared equally between the upper and lower IGBTs of the bridge arm. Based on the comparison principle of the drive signal and feedback signal described above, the first static fault voltage threshold Uth_1 must be less than twice the lower limit threshold U_low of the signal feedback component's hysteresis comparison. Simultaneously, the second static fault voltage threshold Uth_2 must be greater than twice the upper limit threshold U_up of the signal feedback component's hysteresis comparison. That is:

[0113]

[0114] To broaden the DC voltage range for static drive fault detection as much as possible, it is recommended that the static drive fault detection threshold Uth_2 be less than the DC voltage undervoltage protection threshold Udc_min of the drive pulse generation function module, i.e., Uth_2 < Udc_min.

[0115] The choice of t1 can be determined based on the specific circumstances of the converter system.

[0116] For example: when the converter main circuit has pulse-uncontrolled rectification conditions such as intermediate stage pre-charging or pulse blocking but intermediate stage with load, refer to... Figure 7 The thick line indicates the current flow. Because the anti-parallel diode of the IGBT will conduct under uncontrolled rectification conditions, the collector and emitter voltage Vce of this IGBT will be pulled down to the diode forward voltage drop even without a drive signal. Meanwhile, the other IGBT in the same bridge arm bears the DC voltage Udc. Therefore, sufficient margin should be considered for the duration t1 of static drive fault detection under uncontrolled rectification conditions. The duration t1 of static drive fault detection can be set to > half the AC input voltage cycle. Taking 25kV traction power supply as an example, its supply voltage is AC at power frequency. Setting the duration t1 > 0.5 × 20ms, i.e., t1 > 0.5 × Ts, where Ts is the cycle of the AC input signal.

[0117] In some embodiments of the present invention, when a dynamic or static fault occurs, the transmission of drive signals to the converter power devices is stopped. Specifically, if the static fault signal SF is driven... 1-n 1 or drive dynamic fault signal DF 1-n If FP_cmd is 1, the fast protection command is set to 1; otherwise, it is set to 0. When the dynamic fault detection module detects a dynamic fault, or the static fault detection module detects a static fault, the control unit sends a fast protection command to the drive pulse module. When the drive pulse module detects that FP_cmd is 1, the drive pulse generation module controls the fast blocking of the switching pulse, stopping the transmission of drive signals to the power device; otherwise, the pulse state is maintained. At this time, the logic and algorithm operation unit also receives the drive static fault signal SF. 1-n 1 or drive dynamic fault signal DF 1-n If the value is 1, the drive pulse start / stop signal is sent to the drive pulse generation module to ensure that the drive pulse generation module controls the rapid blocking of the switching pulse and stops sending drive signals to the power device.

[0118] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A dynamic and static fault detection system for converter power devices, characterized in that, The converter includes a control unit, a main circuit power device unit, and a DC-side support capacitor, wherein the DC-side support capacitor is connected in parallel with the main circuit power device unit. The control unit includes: a drive pulse generation module, used to send pulse drive signals to the main circuit power device unit and generate pulse generation status signals; The converter further includes: an analog signal acquisition component for acquiring the DC support capacitor voltage signal Udc; a signal feedback component for acquiring the collector-emitter voltage of the power device; and a drive component for receiving pulse drive signals and transmitting them to the power device. The control unit further includes: Static fault detection module: Receives the pulse generation status signal generated by the drive pulse generation module, as well as the collector-emitter voltage signal and the support capacitor voltage signal Udc, to determine whether there is a static fault in the converter power device; Dynamic fault detection module: Receives the pulse generation status signal generated by the drive pulse generation module and the collector-emitter voltage signal to determine whether there is a dynamic fault in the power device of the converter; The pulse generation module is also configured to: block the pulse drive signal when the supported capacitor voltage signal Udc is detected to be less than the converter undervoltage threshold Udc_min. The control unit is configured to: The collector-emitter voltage signal Vce is detected and converted into an output feedback signal to determine whether a dynamic or static fault exists. Methods for converting the collector-emitter voltage signal Vce into an output feedback signal include: Set the first comparison threshold U_up for the feedback voltage and the second comparison threshold U_low for the feedback voltage; If the collector-emitter voltage signal Vce is greater than the first comparison threshold U_up of the feedback voltage, then the feedback signal 1 is output. If the collector-emitter voltage signal Vce is less than the second comparison threshold U_low of the feedback voltage, then the output feedback signal is 0. The dynamic fault detection module is configured as follows: When the drive pulse signal is 1, and the output feedback signal is 1; or, When the drive pulse signal is 0, and the output feedback signal is 0; Then a dynamic fault is determined to exist; The static fault detection module is configured as follows: Set the first static fault voltage threshold Uth_1 and the second static fault voltage threshold Uth_2; If the DC support capacitor voltage Udc signal is less than the first static fault voltage threshold Uth_1, and the output feedback signal is 1; or, The DC support capacitor voltage Udc signal is greater than the second static fault voltage threshold Uth_2, and the output feedback signal is 0. Then a static fault is determined to exist.

2. The converter power device dynamic and static fault detection system as described in claim 1, characterized in that, The control unit further includes a computing unit for receiving static fault detection signals from the static fault detection module and dynamic fault detection signals from the dynamic fault detection module. The arithmetic unit outputs a drive pulse start / stop signal to the drive pulse generation module to control the drive pulse generation module to output a pulse drive signal to the main circuit power unit. When the arithmetic unit detects a static fault signal or a dynamic fault signal, it outputs a pulse stop signal to the drive pulse generation module.

3. A method for detecting dynamic and static faults in converter power devices, characterized in that, The dynamic and static fault detection system described in claim 1 or 2 includes the following steps: Determine the state of the drive pulse enable signal; if it is 1, perform dynamic fault detection; if it is 0, perform static fault detection. Dynamic fault detection methods include: The collector-emitter voltage signal Vce is detected, and the presence of a dynamic fault is determined based on the pulse drive signal and the collector-emitter voltage signal. Static fault detection methods include: Detect the collector-emitter voltage signal Vce and the DC support capacitor voltage Udc signal to determine if there is a static fault. When the supporting capacitor voltage signal Udc is detected to be less than the converter undervoltage threshold Udc_min, the pulse drive signal is blocked. When performing dynamic and static fault detection, the collector-emitter voltage signal Vce is detected and converted into an output feedback signal to determine whether a dynamic or static fault exists. Methods for converting the collector-emitter voltage signal Vce into an output feedback signal include: Set the first comparison threshold U_up for the feedback voltage and the second comparison threshold U_low for the feedback voltage; If the collector-emitter voltage signal Vce is greater than the first comparison threshold U_up of the feedback voltage, then the feedback signal 1 is output. If the collector-emitter voltage signal Vce is less than the second comparison threshold U_low of the feedback voltage, then the output feedback signal is 0. The dynamic fault detection method further includes: When the drive pulse signal is 1, and the output feedback signal is 1; or, When the drive pulse signal is 0, and the output feedback signal is 0; Then a dynamic fault is determined to exist; Static fault detection methods further include: Set the first static fault voltage threshold Uth_1 and the second static fault voltage threshold Uth_2; If the DC support capacitor voltage Udc signal is less than the first static fault voltage threshold Uth_1, and the output feedback signal is 1; or, The DC support capacitor voltage Udc signal is greater than the second static fault voltage threshold Uth_2, and the output feedback signal is 0. Then a static fault is determined to exist.

4. The method for detecting dynamic and static faults in converter power devices as described in claim 3, characterized in that, The dynamic fault detection method further includes: When the drive pulse signal is 1, and the output feedback signal is 1, and the duration exceeds t2; or, When the drive pulse signal is 0, and the output feedback signal is 0, and the duration exceeds t2; Then a dynamic fault is determined to exist.

5. The method for detecting dynamic and static faults in converter power devices as described in claim 3, characterized in that, Static fault detection methods further include: If the DC support capacitor voltage Udc signal is less than the first static fault voltage threshold Uth_1, the output feedback signal 1 is fed back, and the duration is greater than t1; or, When the DC support capacitor voltage Udc signal is greater than the second static fault voltage threshold Uth_2, the output feedback signal is 0, and the duration is greater than t1. Then a static fault is determined to exist.

6. The method for detecting dynamic and static faults in converter power devices as described in claim 3, characterized in that, In the event of a dynamic or static fault, stop sending drive signals to the converter power devices.

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