Fault detection method and device for double-switch PFC circuit and electrical equipment

Abstract

The invention discloses a fault detection method and device for a double-switch PFC circuit and electrical equipment, the double-switch PFC circuit comprises a first switch tube and a second switch tube, the first end of the first switch tube is connected with the first end of the second switch tube, the second end of the first switch tube is connected with the second end of the second switch tube, and the first end of the first switch tube is connected with the second end of the second switch tube. The method comprises the following steps: inputting a control signal to a first switch tube and a second switch tube, so that the first switch tube and the second switch tube are conducted in a staggered manner; obtaining the current of a sampling point, wherein the sampling point is located between the first end of the first switch tube and the first end of the second switch tube or located between the second end of the first switch tube and the second end of the second switch tube; and determining whether the first switch tube and the second switch tube fail or not according to the control signal and the current. According to the method, whether the switch tube has a fault or not and the fault type can be detected according to the type of the control signal and the current of the sampling point, so that accurate identification of the switch tube fault with least signals is realized, and the reliability of the circuit is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical equipment, and in particular to a fault detection method for a dual-switch PFC (Power Factor Correction) circuit, a computer-readable storage medium, an electrical equipment, and a fault detection device for a dual-switch PFC circuit. Background Art

[0002] Most electrical products are designed with PFC circuits to meet the grid's requirements for harmonics. Currently, the most commonly used design for PFC is the Boost circuit. In high-frequency applications, high-frequency switching devices are required, but the high cost of such devices limits their application. The method of using multiple switching devices in parallel to increase the operating frequency is gradually being adopted.

[0003] The PFC circuit uses multiple switching devices in parallel and staggered conduction to increase the operating frequency of the PFC circuit. However, due to the increase in the number of switching devices, the possibility of failure of the switching devices will increase and the stability of the PFC circuit will decrease. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the first object of the present invention is to provide a fault detection method for a dual-switch PFC circuit, which can detect whether a switch tube fails and the type of fault according to the type of control signal and the current at the sampling point, thereby realizing accurate identification of the switch tube fault with the least signal and ensuring the reliability of the circuit.

[0005] A second object of the present invention is to provide a computer-readable storage medium.

[0006] The third object of the present invention is to provide an electrical device.

[0007] A fourth objective of the present invention is to provide a fault detection device for a dual-switch PFC circuit.

[0008] To achieve the above-mentioned purpose, an embodiment of a first aspect of the present invention proposes a fault detection method for a dual-switch PFC circuit, wherein the dual-switch PFC circuit includes a first switch tube and a second switch tube, wherein a first end of the first switch tube is connected to a first end of the second switch tube, and a second end of the first switch tube is connected to a second end of the second switch tube, and the method includes: inputting a control signal to the first switch tube and the second switch tube to make the first switch tube and the second switch tube alternately turned on; obtaining a current at a sampling point, wherein the sampling point is between the first end of the first switch tube and the first end of the second switch tube or between the second end of the first switch tube and the second end of the second switch tube; and determining whether the first switch tube and the second switch tube are faulty according to the control signal and the current.

[0009] According to the fault detection method of the dual-switch PFC circuit of the embodiment of the present invention, a control signal is first input to the first switch tube and the second switch tube to make the first switch tube and the second switch tube conduct alternately, and then the current at the sampling point is obtained, and whether the first switch tube and the second switch tube are faulty is determined according to the control signal and the current. Thus, the method can detect whether the switch tube has a fault and the fault type according to the type of the control signal and the current at the sampling point, thereby realizing accurate identification of the switch tube fault with the least signal, and ensuring the reliability of the circuit.

[0010] In addition, the fault detection method of the dual-switch PFC circuit according to the above embodiment of the present invention may also have the following additional technical features:

[0011] According to one embodiment of the present invention, determining whether the first switch tube and the second switch tube are faulty based on the control signal and the current includes: when the control signal is a turn-on control signal for the first switch tube, if the current is detected, determining that an open circuit fault occurs in the first switch tube; and when the control signal is a turn-off control signal for the first switch tube, if the current is not detected, determining that a short circuit fault occurs in the first switch tube.

[0012] According to another embodiment of the present invention, determining whether the first switch tube and the second switch tube are faulty based on the control signal and the current includes: when the control signal is a shutdown control signal of the first switch tube, if it is detected that the current is on an upward trend, determining that a short circuit fault occurs in the second switch tube; when the control signal is a conduction control signal of the second switch tube, if it is detected that the current is on a downward trend, determining that an open circuit fault occurs in the second switch tube.

[0013] According to one embodiment of the present invention, the method further includes: when an open circuit fault occurs in one of the first switch tube and the second switch tube, controlling the switch tube that has not had an open circuit fault so that the dual-switch PFC circuit continues to work; when a short circuit fault occurs in either the first switch tube or the second switch tube, controlling the dual-switch PFC circuit to stop working.

[0014] According to an embodiment of the present invention, the method further includes: controlling the switch tube that has not had an open circuit fault according to a first operating frequency, wherein the first operating frequency is greater than the operating frequency when both the first switch tube and the second switch tube are normal.

[0015] According to an embodiment of the present invention, when controlling the switch tube that has not had an open circuit failure so that the dual-switch PFC circuit continues to work, the method further includes: reducing the maximum allowable load of the dual-switch PFC circuit.

[0016] According to one embodiment of the present invention, the control signal is input to the first switch tube and the second switch tube so that the first switch tube and the second switch tube are turned on alternately, including: inputting a turn-on control signal to the first switch tube, and when the duration of the turn-on control signal reaches a first preset time, inputting a turn-off control signal to the first switch tube; when the duration of the turn-off control signal reaches a second preset time, inputting a turn-on control signal to the second switch tube, and when the duration of the turn-on control signal reaches a third preset time, inputting a turn-off control signal to the second switch tube; when the duration of the turn-off control signal reaches a fourth preset time, inputting a turn-on control signal to the first switch tube again, and repeating this process.

[0017] To achieve the above-mentioned purpose, a second aspect of the present invention provides a computer-readable storage medium having a program stored thereon, which implements the above-mentioned fault detection method for the dual-switch PFC circuit when executed by a processor.

[0018] According to the computer-readable storage medium of the embodiment of the present invention, through the above-mentioned fault detection method of the dual-switch PFC circuit, it is possible to accurately identify the fault of the switch tube with the least signal, thereby ensuring the reliability of the circuit.

[0019] To achieve the above-mentioned purpose, the third aspect of the present invention proposes an electrical device, comprising: a memory, a processor, and a program stored in the memory and executable on the processor, wherein when the processor executes the program, the fault detection method of the dual-switch PFC circuit is implemented.

[0020] According to the electrical equipment of the embodiment of the present invention, through the above-mentioned dual-switch PFC circuit fault detection method, it is possible to accurately identify the fault of the switch tube with the least signal, thereby ensuring the reliability of the circuit.

[0021] To achieve the above-mentioned purpose, a fourth aspect of the present invention provides a fault detection device for a dual-switch PFC circuit, wherein the dual-switch PFC circuit includes a first switch tube and a second switch tube, wherein a first end of the first switch tube is connected to a first end of the second switch tube, and a second end of the first switch tube is connected to a second end of the second switch tube, and the device includes: a control module, configured to input a control signal to the first switch tube and the second switch tube so that the first switch tube and the second switch tube are alternately turned on; an acquisition module, configured to acquire a current at a sampling point, wherein the sampling point is between the first end of the first switch tube and the first end of the second switch tube or between the second end of the first switch tube and the second end of the second switch tube; and the control module is further configured to determine whether the first switch tube and the second switch tube are faulty according to the control signal and the current.

[0022] According to the fault detection device of the dual-switch PFC circuit of the embodiment of the present invention, the control module inputs a control signal to the first switch tube and the second switch tube to make the first switch tube and the second switch tube conduct alternately; the acquisition module acquires the current at the sampling point, and the sampling point is between the first end of the first switch tube and the first end of the second switch tube or between the second end of the first switch tube and the second end of the second switch tube; the control module determines whether the first switch tube and the second switch tube are faulty according to the control signal and the current. Thus, the device can detect whether the switch tube is faulty and the fault type according to the type of the control signal and the current at the sampling point, thereby realizing accurate identification of the switch tube fault with the least signal, and ensuring the reliability of the circuit.

[0023] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a flow chart of a fault detection method for a dual-switch PFC circuit according to an embodiment of the present invention;

[0025] Figure 2 A hardware topology diagram of a dual-switch PFC circuit according to an embodiment of the present invention;

[0026] Figure 3 is a waveform diagram of a sampling current when the first switch tube and the second switch tube are both normal according to an embodiment of the present invention;

[0027] Figure 4is a waveform diagram of a sampling current when an open circuit fault occurs in the first switch tube according to an embodiment of the present invention;

[0028] Figure 5 is a waveform diagram of a sampling current when a short circuit fault occurs in a first switch tube according to an embodiment of the present invention;

[0029] Figure 6 is a waveform diagram of a sampling current when a short circuit fault occurs in the second switch tube according to an embodiment of the present invention;

[0030] Figure 7 is a waveform diagram of a sampling current when an open circuit fault occurs in the second switch tube according to an embodiment of the present invention;

[0031] Figure 8 A waveform diagram of a sampling current in various situations according to an embodiment of the present invention;

[0032] Fig. 9 is a flow chart of a fault detection method for a dual-switch PFC circuit according to an embodiment of the present invention;

[0033] Fig.10 is a block diagram of an electrical device according to an embodiment of the present invention;

[0034] Fig.11 FIG. 4 is a block diagram of a fault detection device for a dual-switch PFC circuit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0036] The following describes a dual-switch PFC circuit fault detection method, a computer-readable storage medium, an electrical device, and a dual-switch PFC circuit fault detection device according to embodiments of the present invention with reference to the accompanying drawings.

[0037] Figure 1 4 is a flow chart of a fault detection method for a dual-switch PFC circuit according to an embodiment of the present invention.

[0038] In one embodiment of the present invention, Figure 2As shown, the dual-switch PFC circuit includes a first switch tube S1 and a second switch tube S2, wherein the first end of the first switch tube S1 is connected to the first end of the second switch tube S2, and the second end of the first switch tube S1 is connected to the second end of the second switch tube S2. One end of the PFC inductor L is connected to the rectifier, and the other end is connected to the first end of the first switch tube S1. The anode of the diode D is connected to the first end of the second switch tube S2, and the cathode of the diode D is respectively connected to the positive electrode of the first capacitor C and one end of the load. The control unit is respectively connected to the third end of the first switch tube S1 and the third end of the second switch tube S2, and provides a control signal G1 to the first switch tube S1 and a control signal G2 to the second switch tube S2, so as to control the first switch tube S1 and the second switch tube S2 to be turned on or off.

[0039] like Figure 1 As shown, the fault detection method of the dual-switch PFC circuit of the embodiment of the present invention may include the following steps:

[0040] Step S1, inputting a control signal to a first switch tube and a second switch tube, so that the first switch tube and the second switch tube are turned on alternately.

[0041] According to an embodiment of the present invention, inputting a control signal to a first switch tube and a second switch tube so that the first switch tube and the second switch tube are alternately turned on includes: inputting a turn-on control signal to the first switch tube, and when the duration of the turn-on control signal reaches a first preset time, inputting a turn-off control signal to the first switch tube; when the duration of the turn-off control signal reaches a second preset time, inputting a turn-on control signal to the second switch tube, and when the duration of the turn-on control signal reaches a third preset time, inputting a turn-off control signal to the second switch tube; when the duration of the turn-off control signal reaches a fourth preset time, inputting a turn-on control signal to the first switch tube again, and repeating this process. The first preset time, the second preset time, the third preset time, and the fourth preset time can all be calibrated according to actual conditions.

[0042] Specifically, the timing sequence of the control signal G1 of the first switch tube and the control signal G2 of the second switch tube is as follows: Figure 2As shown, when the first switch tube and the second switch tube are both normal and without fault, the control unit outputs a high-level control signal G1 to the first switch tube to control the first switch tube to be turned on, and the PFC inductor is charged; after the first preset time is continued, the control signal G1 of the first switch tube becomes a low level, controls the first switch tube to be turned off, and the PFC inductor is discharged; after the second preset time is continued, the control unit outputs a high-level control signal G2 to the second switch tube to control the second switch tube to be turned on, and the PFC inductor is charged; after the third preset time is continued, the control signal G2 of the second switch tube becomes a low level, controls the second switch tube to be turned off, and the PFC inductor is discharged; after the fourth preset time is continued, the control unit outputs a high-level control signal G1 to the first switch tube again to control the first switch tube to be turned on, and this is repeated.

[0043] Step S2, obtaining the current at a sampling point, where the sampling point is between the first end of the first switch tube and the first end of the second switch tube or between the second end of the first switch tube and the second end of the second switch tube.

[0044] The current at the sampling point can be collected by a sampling resistor, a Hall sensor, a current transformer, etc. The sampling point can be set between the first end of the first switch tube and the first end of the second switch tube, that is, Figure 2 or between the second end of the first switch tube and the second end of the second switch tube, that is, Figure 2 The sampling point B in .

[0045] Step S3, determining whether the first switch tube and the second switch tube are faulty according to the control signal and the current.

[0046] Specifically, Figure 3 The waveform diagram of the sampling current shown in is the current waveform when the first switch tube and the second switch tube are both normal. When the control signal G1 is at a high level, the first switch tube is turned on, the PFC inductor is charged, and no current flows through the sampling point, that is, the current at the sampling point is zero. When the control signal G1 is at a low level, the first switch tube is turned off, the PFC inductor is discharged, and the current at the sampling point gradually decreases. When the control signal G2 is at a high level, the second switch tube is turned on, the PFC inductor is charged, and the current at the sampling point continues to increase. When the control signal G2 is at a low level, the second switch tube is turned off, the PFC inductor is discharged, and the current at the sampling point gradually decreases.

[0047] When the first switch tube or the second switch tube fails, the failed switch tube cannot operate according to the corresponding control signal, so that the current at the sampling point changes, and thus which switch tube fails and the type of failure can be determined based on the control signal and the current at the sampling point. For example, when the control signal G1 is at a low level, the current at the sampling point is zero, and it can be determined that the first switch tube fails to turn off and a short circuit failure occurs.

[0048] According to one embodiment of the present invention, determining whether the first switch tube and the second switch tube are faulty is performed based on a control signal and a current, including: when the control signal is a turn-on control signal of the first switch tube, if a current is detected, determining that an open circuit fault occurs in the first switch tube; when the control signal is a turn-off control signal of the first switch tube, if no current is detected, determining that a short circuit fault occurs in the first switch tube.

[0049] Specifically, when the first switch tube has an open circuit fault, when the control signal G1 is at a high level, the first switch tube cannot be turned on and remains in the off state, and the PFC inductor discharges. At this time, a current flows through the sampling point, and the current gradually decreases. When the control signal G1 becomes a low level, the current at the sampling point continues to decrease. When the control signal G2 is at a high level and the second switch tube is closed, the current at the sampling point rises again. The corresponding sampling current waveform is as follows: Figure 4 Therefore, when the control signal G1 is at a high level to control the first switch tube to be turned on, if the sampling point can detect the current, it can be determined that the first switch tube has an open circuit fault.

[0050] When the first switch tube has a short circuit fault, the current flows directly through the first switch tube without passing through the sampling point. Therefore, no matter how the control signal changes, the current at the sampling point is always zero. The corresponding sampling current waveform is as follows: Figure 5 Therefore, when the control signal G1 is at a low level to control the first switch tube to be turned off, if no current is detected at the sampling point, it can be determined that a short circuit fault occurs in the first switch tube.

[0051] According to one embodiment of the present invention, determining whether the first switch tube and the second switch tube are faulty is performed based on a control signal and a current, including: when the control signal is a shutdown control signal of the first switch tube, if it is detected that the current is increasing, determining that a short circuit fault occurs in the second switch tube; when the control signal is a conduction control signal of the second switch tube, if it is detected that the current is decreasing, determining that an open circuit fault occurs in the second switch tube.

[0052] Specifically, when the second switch tube has a short circuit fault, when the control signal G1 is at a high level, the first switch tube is turned on, and the current at the sampling point is zero. When the control signal G1 is at a low level, the first switch tube is turned off, the PFC inductor is charged, and the current flows through the second switch tube. The current at the sampling point continues to increase and shows an upward trend. Since the second switch tube is short-circuited, the PFC inductor continues to charge, and the control signal G2 cannot control the second switch tube. The current at the sampling point continues to increase and shows an upward trend until the next time the first switch tube is turned on. The corresponding sampling current waveform is as follows: Figure 6As shown. It can be seen from the analysis of the above embodiments that when the switch tube does not fail, when the first switch tube is turned off, the current at the sampling point continues to decrease and shows a downward trend. Therefore, when the control signal G1 is at a low level to control the first switch tube to be turned off, if the sampling point shows an upward trend, it can be determined that a short circuit failure occurs in the second switch tube.

[0053] When the second switch tube has an open circuit fault, when the control signal G1 is at a high level, the first switch tube is turned on, and the current at the sampling point is zero. When the control signal G1 is at a low level, the first switch tube is turned off, the PFC inductor is discharged, and the current at the sampling point continues to decrease and shows a downward trend. Since the second switch is open, when the control signal G2 is at a high level, the second switch tube cannot be turned on and remains in the off state, the PFC inductor continues to discharge, and the current at the sampling point continues to decrease and shows a downward trend until the next time the first switch tube is turned on. The corresponding sampling current waveform is as follows: Figure 7 Therefore, when the control signal G2 is at a high level, if the current at the sampling point continues to decrease and shows a downward trend, it can be determined that an open circuit fault occurs in the second switch tube.

[0054] It should be noted that Figure 8 This is a schematic diagram of the sampling current waveform under normal conditions of the switch tube and various faults of the switch tube. Figure 8 It can be found that as long as a switch tube fails, the waveform of the sampled current will change accordingly and is different from the current waveform under normal circumstances. Therefore, the control signal and current can accurately determine which switch tube has failed and the type of failure.

[0055] According to one embodiment of the present invention, the above method also includes: when an open circuit fault occurs in one of the first switch tube and the second switch tube, controlling the switch tube that has not had an open circuit fault so that the dual-switch PFC circuit continues to work; when a short circuit fault occurs in either the first switch tube or the second switch tube, controlling the dual-switch PFC circuit to stop working.

[0056] Specifically, it can be seen from the above analysis that when a short circuit occurs in the first switch tube or the second switch tube, the PFC inductor is in a continuous charging state and cannot supply power to the load, and the dual-switch PFC circuit cannot work normally, so it is necessary to control the dual-switch PFC circuit to stop working; when an open circuit occurs in the first switch tube or the second switch tube, the PFC inductor can discharge to the outside to supply power to the load, so the normal switch tube can be controlled to make the dual-switch PFC circuit continue to work. For example, when an open circuit occurs in the second switch tube, the control unit can output a control signal G1 to control the first switch tube so that the dual-switch PFC circuit continues to work.

[0057] Further, according to an embodiment of the present invention, the method further includes: controlling the switch tube that has not had an open circuit fault according to a first operating frequency, wherein the first operating frequency is greater than the operating frequency when both the first switch tube and the second switch tube are normal.

[0058] For example, when an open-circuit fault occurs in the second switch tube, the control unit can increase the frequency of the output control signal G1 to the first operating frequency, drive the first switch tube, and make the dual-switch PFC circuit maintain the original power factor and continue to work.

[0059] According to an embodiment of the present invention, when controlling the switch tube that has not had an open circuit failure so that the dual-switch PFC circuit continues to work, the method further includes: reducing the maximum allowable load of the dual-switch PFC circuit.

[0060] Specifically, when an open-circuit fault occurs in one of the first switch tube and the second switch tube, if the dual-switch PFC circuit still drives the load with the maximum allowable load output power when no fault occurs, the load continues to operate at the original power, which may cause the dual-switch PFC circuit to fail or even cause a safety accident. Therefore, when an open-circuit fault occurs in one of the first switch tube and the second switch tube, it is necessary to reduce the maximum allowable load of the dual-switch PFC circuit, reduce the output power of the dual-switch PFC circuit, prevent the dual-switch PFC circuit from failing, and ensure safety.

[0061] As a specific example, Fig. 9 As shown, the fault detection method of the dual-switch PFC circuit may include the following steps:

[0062] Step S201, input a control signal G1 to the first switch tube, and input a control signal G2 to the second switch tube.

[0063] Step S202, obtaining the current at the sampling point.

[0064] Step S203, determining whether current is detected when the control signal G1 is at a high level. If yes, execute step S204; if no, execute step S205.

[0065] Step S204: an open circuit failure occurs in the first switch tube, and the second switch tube is controlled according to the first operating frequency.

[0066] Step S205, determining whether current is detected when the control signal G1 is at a low level. If not, executing step S206; if yes, executing step S207.

[0067] Step S206: A short circuit fault occurs in the first switch tube, and the dual-switch PFC circuit is controlled to stop working.

[0068] Step S207, determine whether the current is on an upward trend. If yes, execute step S208; if no, execute step S209.

[0069] Step S208: a short circuit fault occurs in the second switch tube, and the dual-switch PFC circuit is controlled to stop working.

[0070] Step S209, determining whether the current detected when the control signal G2 is at a high level is in a downward trend. If yes, executing step S210; if no, returning to step S202.

[0071] Step S210: an open circuit failure occurs in the second switch tube, and the first switch tube is controlled according to the first operating frequency.

[0072] In summary, according to the fault detection method of the dual-switch PFC circuit of the embodiment of the present invention, a control signal is first input to the first switch tube and the second switch tube to make the first switch tube and the second switch tube conduct alternately, and then the current at the sampling point is obtained, and whether the first switch tube and the second switch tube are faulty is determined according to the control signal and the current. Therefore, the method can detect whether the switch tube has a fault and the fault type according to the type of the control signal and the current at the sampling point, thereby realizing accurate identification of the switch tube fault with the least signal, and ensuring the reliability of the circuit.

[0073] Corresponding to the above embodiment, the present invention also proposes a computer-readable storage medium.

[0074] The computer-readable storage medium of the present invention stores a program thereon, and when the program is executed by a processor, the fault detection method of the dual-switch PFC circuit described above is implemented.

[0075] According to the computer-readable storage medium of the embodiment of the present invention, through the above-mentioned fault detection method of the dual-switch PFC circuit, it is possible to accurately identify the fault of the switch tube with the least signal, thereby ensuring the reliability of the circuit.

[0076] Corresponding to the above embodiment, the present invention also proposes an electrical device.

[0077] Fig.10 FIG. 4 is a block diagram of an electrical device according to an embodiment of the present invention.

[0078] like Fig.10 As shown, the electrical device 200 of the embodiment of the present invention includes: a memory 210, a processor 220, and a program stored in the memory 210 and executable on the processor 220. When the processor 220 executes the program, the fault detection method of the dual-switch PFC circuit described above is implemented.

[0079] According to the electrical equipment of the embodiment of the present invention, through the above-mentioned dual-switch PFC circuit fault detection method, it is possible to accurately identify the fault of the switch tube with the least signal, thereby ensuring the reliability of the circuit.

[0080] Corresponding to the above embodiment, the present invention further proposes a fault detection device for a dual-switch PFC circuit.

[0081] Fig.11 FIG. 4 is a block diagram of a fault detection device for a dual-switch PFC circuit according to an embodiment of the present invention.

[0082] like Fig.11 As shown, a fault detection device 100 for a dual-switch PFC circuit according to an embodiment of the present invention, the dual-switch PFC circuit includes a first switch tube and a second switch tube, the first end of the first switch tube is connected to the first end of the second switch tube, and the second end of the first switch tube is connected to the second end of the second switch tube, and the device 100 includes: a control module 110 and an acquisition module 120.

[0083] The control module 110 is used to input a control signal to the first switch tube and the second switch tube so that the first switch tube and the second switch tube are turned on alternately. The acquisition module 120 is used to acquire the current at a sampling point, where the sampling point is between the first end of the first switch tube and the first end of the second switch tube or between the second end of the first switch tube and the second end of the second switch tube. The control module 110 is also used to determine whether the first switch tube and the second switch tube are faulty according to the control signal and the current.

[0084] According to one embodiment of the present invention, the control module 110 determines whether the first switch tube and the second switch tube are faulty based on the control signal and the current. Specifically, when the control signal is a turn-on control signal of the first switch tube, if the current is detected, it is determined that the first switch tube has an open circuit fault; when the control signal is a turn-off control signal of the first switch tube, if the current is not detected, it is determined that the first switch tube has a short circuit fault.

[0085] According to one embodiment of the present invention, the control module 110 determines whether the first switch tube and the second switch tube are faulty based on the control signal and the current. Specifically, when the control signal is a shutdown control signal of the first switch tube, if it is detected that the current is increasing, it is determined that a short circuit fault occurs in the second switch tube; when the control signal is a conduction control signal of the second switch tube, if it is detected that the current is decreasing, it is determined that an open circuit fault occurs in the second switch tube.

[0086] According to one embodiment of the present invention, the control module 110 is further used to, when an open circuit fault occurs in one of the first switch tube and the second switch tube, control the switch tube that has not had an open circuit fault so that the dual-switch PFC circuit continues to work; when a short circuit fault occurs in either the first switch tube or the second switch tube, control the dual-switch PFC circuit to stop working.

[0087] According to an embodiment of the present invention, the control module 110 is further used to control the switch tube without open circuit failure according to a first operating frequency, wherein the first operating frequency is greater than the operating frequency when both the first switch tube and the second switch tube are normal.

[0088] According to an embodiment of the present invention, when controlling the switch tube that has not had an open circuit fault so that the dual-switch PFC circuit continues to work, the control module 110 is further configured to reduce the maximum allowable load of the dual-switch PFC circuit.

[0089] According to one embodiment of the present invention, the control module 110 inputs a control signal to the first switch tube and the second switch tube so that the first switch tube and the second switch tube are turned on alternately, specifically, inputs a turn-on control signal to the first switch tube, and when the duration of the turn-on control signal reaches a first preset time, inputs a turn-off control signal to the first switch tube; when the duration of the turn-off control signal reaches a second preset time, inputs a turn-on control signal to the second switch tube, and when the duration of the turn-on control signal reaches a third preset time, inputs a turn-off control signal to the second switch tube; when the duration of the turn-off control signal reaches a fourth preset time, inputs a turn-on control signal to the first switch tube again, and repeats this process.

[0090] It should be noted that for details not disclosed in the fault detection device for the dual-switch PFC circuit in the embodiment of the present invention, please refer to the details disclosed in the fault detection method for the dual-switch PFC circuit in the embodiment of the present invention, and no further details will be given here.

[0091] According to the fault detection device of the dual-switch PFC circuit of the embodiment of the present invention, the control module inputs a control signal to the first switch tube and the second switch tube to make the first switch tube and the second switch tube conduct alternately; the acquisition module acquires the current at the sampling point, and the sampling point is between the first end of the first switch tube and the first end of the second switch tube or between the second end of the first switch tube and the second end of the second switch tube; the control module determines whether the first switch tube and the second switch tube are faulty according to the control signal and the current. Thus, the device can detect whether the switch tube is faulty and the fault type according to the type of the control signal and the current at the sampling point, thereby realizing accurate identification of the switch tube fault with the least signal, and ensuring the reliability of the circuit.

[0092] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0093] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0094] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0095] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0096] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0097] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A fault detection method for a dual-switch PFC circuit, characterized in that: The dual-switch PFC circuit includes a first switch tube and a second switch tube, wherein a first end of the first switch tube is connected to a first end of the second switch tube, and a second end of the first switch tube is connected to a second end of the second switch tube. The method includes: Inputting a control signal to the first switch tube and the second switch tube so that the first switch tube and the second switch tube are turned on alternately; Acquire a current at a sampling point, where the sampling point is between the first end of the first switch tube and the first end of the second switch tube or between the second end of the first switch tube and the second end of the second switch tube; It is determined whether the first switch tube and the second switch tube are faulty according to the control signal and the current.

2. The method according to claim 1, characterized in that The determining, according to the control signal and the current, whether the first switch tube and the second switch tube are faulty includes: When the control signal is a turn-on control signal of the first switch tube, if the current is detected, it is determined that an open circuit fault occurs in the first switch tube; When the control signal is a turn-off control signal of the first switch tube, if the current is not detected, it is determined that a short circuit fault occurs in the first switch tube.

3. The method according to claim 1, characterized in that The determining, according to the control signal and the current, whether the first switch tube and the second switch tube are faulty includes: When the control signal is a turn-off control signal of the first switch tube, if it is detected that the current is on an upward trend, it is determined that a short circuit fault occurs in the second switch tube; When the control signal is a turn-on control signal of the second switch tube, if it is detected that the current is in a downward trend, it is determined that an open circuit fault occurs in the second switch tube.

4. The method according to any one of claims 1 to 3, characterized in that: The method further comprises: When an open circuit fault occurs in one of the first switch tube and the second switch tube, controlling the switch tube that does not have the open circuit fault so that the dual-switch PFC circuit continues to work; When a short circuit fault occurs in any one of the first switch tube and the second switch tube, the dual-switch PFC circuit is controlled to stop working.

5. The method according to claim 4, characterized in that The method further comprises: The switch tube that has not had an open circuit fault is controlled according to a first operating frequency, wherein the first operating frequency is greater than the operating frequency when both the first switch tube and the second switch tube are normal.

6. The method according to claim 4, characterized in that When the switch tube that has not had an open circuit fault is controlled so that the dual-switch PFC circuit continues to work, the method further includes: The maximum allowable load of the dual-switch PFC circuit is reduced.

7. The method according to claim 1, characterized in that The step of inputting a control signal to the first switch tube and the second switch tube so as to make the first switch tube and the second switch tube conduct alternately includes: Inputting a conduction control signal to the first switch tube, and inputting a shutdown control signal to the first switch tube when the duration of the conduction control signal reaches a first preset time; When the duration of the shutdown control signal reaches a second preset time, a conduction control signal is input to the second switch tube, and when the duration of the conduction control signal reaches a third preset time, a shutdown control signal is input to the second switch tube; When the duration of the turn-off control signal reaches a fourth preset time, the turn-on control signal is input to the first switch tube again, and this process is repeated.

8. A computer-readable storage medium, characterized in that: A program is stored thereon, and when the program is executed by a processor, the fault detection method for a dual-switch PFC circuit according to any one of claims 1 to 7 is implemented.

9. An electrical device, characterized in that: include: A memory, a processor, and a program stored in the memory and executable on the processor, wherein when the processor executes the program, the fault detection method for the dual-switch PFC circuit according to any one of claims 1 to 7 is implemented.

10. A fault detection device for a dual-switch PFC circuit, characterized in that: The dual-switch PFC circuit includes a first switch tube and a second switch tube, wherein a first end of the first switch tube is connected to a first end of the second switch tube, and a second end of the first switch tube is connected to a second end of the second switch tube, and the device includes: A control module, used for inputting a control signal to the first switch tube and the second switch tube so as to make the first switch tube and the second switch tube conduct alternately; an acquisition module, configured to acquire a current at a sampling point, wherein the sampling point is between the first end of the first switch tube and the first end of the second switch tube or between the second end of the first switch tube and the second end of the second switch tube; The control module is further used to determine whether the first switch tube and the second switch tube are faulty according to the control signal and the current.

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