Fault detection method, circuit, medium, product, equipment, controller and vehicle

Abstract

The invention relates to a fault detection method and circuit, a medium, a product, equipment, a controller and a vehicle, and the method comprises the steps: obtaining a first current flowing through a first inductor and a second current flowing through a second inductor in a first mode; whether the first bridge arm and / or the second bridge arm are / is faulty is determined based on the direction comparison result of the first current and the second current, so that the fault detection process is simplified, fault detection is realized without adopting a desaturation detection function, the situation that fault detection cannot be realized due to the adoption of a driving chip is avoided, and the fault detection efficiency is improved. Therefore, the reliability of fault detection is improved.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to a fault detection method, circuit, medium, product, equipment, controller and vehicle. Background Art

[0002] A DC-DC converter is used to convert a DC input voltage into another DC output voltage, and usually includes multiple single-phase bridge arms connected in parallel.

[0003] The fault detection of transistors in these single-phase bridge arms needs to rely on the desaturation detection function of the driver chip to be implemented. It is necessary to specifically combine the fault detection signal of the upper bridge arm and the fault detection signal of the lower bridge arm in each phase bridge arm to diagnose the fault of the transistor.

[0004] This not only increases the complexity of fault detection, but also causes the driver chip to lose its fault detection function due to random failures of the driver chip, or interference that causes the driver chip to frequently falsely report faults, thereby turning off the desaturation detection function and reducing the reliability of fault detection. Summary of the invention

[0005] The embodiments of the present application provide a fault detection method, circuit, medium, product, equipment, controller and vehicle, which reduce the complexity of the fault detection method and improve the reliability of the fault detection method, so as to at least partially solve the above-mentioned technical problems.

[0006] In order to achieve the above-mentioned purpose, according to the first aspect of the present application, a fault detection method is provided, which is applied to a bidirectional DC converter, the bidirectional DC converter includes a first inductor and a second inductor, the bidirectional DC converter also includes a first bridge arm connected to the first inductor and a second bridge arm connected to the second inductor, the first bridge arm and the second bridge arm are connected in parallel, and the fault detection method includes: obtaining a first current flowing through the first inductor and a second current flowing through the second inductor in a first mode; based on a direction comparison result of the first current and the second current, determining whether the first bridge arm and / or the second bridge arm is faulty.

[0007] According to a second aspect of the present application, a fault detection circuit is provided, which executes the above-mentioned fault detection method.

[0008] According to a third aspect of the present application, a storage medium is provided, which stores a computer program, and the computer program implements the above-mentioned fault detection method when executed by a processor.

[0009] According to a fourth aspect of the present application, a computer program product is provided, the computer program product comprising a computer program, and the computer program implements the above-mentioned fault detection method when executed by a processor.

[0010] According to a fifth aspect of the present application, an electronic device is provided, the electronic device comprising the above-mentioned fault detection circuit, or the electronic device comprising the above-mentioned storage medium.

[0011] According to a sixth aspect of the present application, a controller is provided, which includes a memory and a processor, wherein a computer program is stored in the memory; the processor is used to execute the computer program in the memory to implement the above-mentioned fault detection method.

[0012] According to a seventh aspect of the present application, a vehicle is provided, which includes the above-mentioned electronic device or controller.

[0013] The fault detection method, circuit, medium, product, equipment, controller and vehicle of the embodiments of the present application obtain the first current flowing through the first inductor and the second current flowing through the second inductor in the first mode, and determine whether the first bridge arm and / or the second bridge arm is faulty based on the result of comparing the directions of the first current and the second current. This not only simplifies the fault detection process, but also avoids the situation where fault detection cannot be achieved due to the use of a driver chip because the desaturation detection function is not used to implement fault detection, thereby improving the reliability of fault detection.

[0014] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0016] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same figure numbers represent the same parts in the following description.

[0017] Figure 1 is a driving circuit diagram of an electric vehicle provided in an exemplary embodiment of the present disclosure;

[0018] Figure 2 is a first flow chart of a fault detection method provided in an exemplary embodiment of the present disclosure;

[0019] Figure 3 is a schematic diagram of current flow under a fault condition provided in an exemplary embodiment of the present disclosure;

[0020] Figure 4is a schematic diagram of current flow under a driving condition provided in an exemplary embodiment of the present disclosure;

[0021] Figure 5 is a schematic diagram of current flow under power generation conditions provided in an exemplary embodiment of the present disclosure;

[0022] Figure 6 is a second flow chart of a fault detection method provided in an exemplary embodiment of the present disclosure;

[0023] Figure 7 is a third flow chart of the fault detection method provided in the exemplary embodiment of the present disclosure.

[0024] Description of reference numerals:

[0025] 10. Bidirectional DC converter; 11. First bridge arm; 12. Second bridge arm. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0027] Figure 1 1 is a driving circuit diagram of an electric vehicle provided in an exemplary embodiment of the present disclosure. The electric vehicle includes a first inductor L1, a second inductor L2, and a bidirectional DC converter 10, wherein the bidirectional DC converter 10 includes a first bridge arm 11 connected to the first inductor L1 and a second bridge arm 12 connected to the second inductor L2, wherein the first bridge arm 11 and the second bridge arm 12 are connected in parallel.

[0028] The direction of the first current Im flowing through the first inductor L1 is defined as the direction from the first inductor L1 to the first bridge arm 11 as the positive direction, and the direction from the first inductor L1 to the first bridge arm 11 as the negative direction. The direction of the second current In flowing through the second inductor L2 is defined as the direction from the second inductor L2 to the second bridge arm 12 as the positive direction, and the direction from the second inductor L2 to the second bridge arm 12 as the negative direction.

[0029] The first bridge arm 11 and the second bridge arm 12 are both used as a single-phase bridge arm. The first power semiconductor device V1 is used as the upper bridge arm of the first bridge arm 11, and the second power semiconductor device V2 is used as the lower bridge arm of the first bridge arm 11. The third power semiconductor device V3 is used as the upper bridge arm of the second bridge arm 12, and the fourth power semiconductor device V4 is used as the lower bridge arm of the second bridge arm 12.

[0030] Optionally, the electric vehicle further includes a power battery B1, a fuse F1 and a first capacitor C2, the positive electrode of the power battery B1 is connected to one end of the fuse F1, the other end of the fuse F1 is connected to one end of the first capacitor C2, the first inductor L1 and the second inductor L2, and the negative electrode of the power battery B1 is connected to the other end of the first capacitor C2, one end of the first bridge arm 11 and one end of the second bridge arm 12. The voltage across the first capacitor C2 is U1.

[0031] Optionally, the electric vehicle further includes a second capacitor C1 and a DC motor M. The second capacitor C1 is connected in parallel to the first bridge arm 11 or the second bridge arm 12, and the DC motor M is connected in parallel to the second capacitor C1. The voltage across the second capacitor C1 is U2.

[0032] The present application provides a fault detection method, which is applied to a bidirectional DC converter 10 of an electric vehicle. Figures 1 to 7 ,like Figure 2 As shown, the fault detection method includes the following steps:

[0033] Step S10: obtaining a first current flowing through the first inductor and a second current flowing through the second inductor in the first mode.

[0034] Step S20: Based on the comparison result of the directions of the first current and the second current, determine whether the first bridge arm and / or the second bridge arm is faulty.

[0035] It can be understood that the fault detection method of the embodiment of the present application obtains the first current Im flowing through the first inductor L1 and the second current In flowing through the second inductor L2 in the first mode, and determines whether the first bridge arm 11 and / or the second bridge arm 12 are faulty based on the direction comparison result of the first current Im and the second current In. This not only simplifies the fault detection process, but also avoids the situation where fault detection cannot be achieved due to the use of a driver chip because the desaturation detection function is not used to implement fault detection, thereby improving the reliability of fault detection.

[0036] It should be noted that the first mode is the boost mode. Figure 1 In the embodiment, when U1 is used as the input voltage of the bidirectional DC converter 10 and U2 is used as the output voltage of the bidirectional DC converter 10, the case where U2 is greater than U1 is the boost mode; or, when U1 is used as the output voltage of the bidirectional DC converter 10 and U2 is used as the input voltage of the bidirectional DC converter 10, the case where U1 is greater than U2 is the boost mode.

[0037] Optionally, if the direction comparison result is that the direction of the first current Im is different from the direction of the second current In, it is determined that the first bridge arm 11 and / or the second bridge arm 12 is faulty.

[0038] It should be noted that the direction of the first current Im is the direction from the first inductor L1 to the first bridge arm 11 as the positive direction, and the direction of the first current Im is the direction from the first bridge arm 11 to the first inductor L1 as the negative direction. The direction of the second current In is the direction from the second inductor L2 to the second bridge arm 12 as the positive direction, and the direction of the second current In is the direction from the second bridge arm 12 to the second inductor L2 as the negative direction.

[0039] like Figure 3 As shown, when a system fault occurs, for example, when the desaturation detection function of the driver chip used to detect the fault condition of the fourth power semiconductor device V4 fails or is configured to be turned off, if a short circuit fault occurs in the fourth power semiconductor device V4, the driver chip cannot detect the short circuit fault and cannot shut down the fourth power semiconductor device V4 in time, which will cause the power battery B1 to short-circuit and the fuse F1 to blow.

[0040] If it is in the power generation state at this time, that is, the motor M is charging the power battery B1 through the bidirectional DC converter 10, the current flow direction at this time is as follows: Figure 3 As shown by the arrows in , the current flows from the positive pole of the motor M through the first power semiconductor device V1, the first inductor L1 and the second inductor L2 in sequence, merges with the current flowing through the third power semiconductor device V3, flows through the fourth power semiconductor device V4, and then flows to the negative pole of the motor M.

[0041] In this case, the direction of the first current Im is opposite to the direction of the second current In, that is, the direction of the first current Im is negative, and the direction of the second current In is positive. It can be determined that the bidirectional DC converter 10 is faulty.

[0042] Optionally, the direction comparison result is that the direction of the first current Im is different from the direction of the second current In, including: determining whether the first current Im is greater than a first preset current value, and whether the second current In is less than or equal to the second preset current value; if the first current Im is greater than the first preset current value, and the second current In is less than or equal to the second preset current value, then determining that the direction of the first current Im is different from the direction of the second current In.

[0043] It needs to be explained that if Figure 6 As shown, the first preset current value can be exemplarily 30 A, and the second preset current value can be exemplarily -30 A. The first preset current value and the second preset current value can be set as needed, in order to improve the accuracy of whether the direction of the first current Im is the same as the direction of the second current In, thereby improving the accuracy of fault judgment.

[0044] Optionally, if the first current Im is greater than a first preset current value, and the second current In is less than or equal to a second preset current value, then it is determined that the direction of the first current Im is different from the direction of the second current In, including: obtaining the duration of time during which the first current Im is greater than the first preset current value, and the second current In is less than or equal to the second preset current value; if the duration is greater than or equal to the first preset duration, then it is determined that the direction of the first current Im is different from the direction of the second current In.

[0045] It needs to be explained that if Figure 6 As shown, when the conditions that the first current Im is greater than the first preset current value and the second current In is less than or equal to the second preset current value are met, it indicates that a fault has occurred, and the fault will trigger the timer to obtain the duration of the first current Im being greater than the first preset current value and the second current In being less than or equal to the second preset current value. The first preset duration can be exemplarily 400us, and when the duration, i.e., the fault trigger timing, is greater than or equal to 400us, it is determined that the direction of the first current Im is opposite to the direction of the second current In, and it is determined to be a bridge arm fault.

[0046] Alternatively, if Figure 6 As shown, after determining whether the first current Im is greater than the first preset current value and whether the second current In is less than or equal to the second preset current value, it also includes: if not, determining whether the first current Im is less than the second preset current value and whether the second current In is greater than the first preset current value; if it is determined that the first current Im is less than the second preset current value and the second current In is greater than the first preset current value, then determining that the direction of the first current Im is different from the direction of the second current In.

[0047] Optionally, if it is determined that the first current Im is less than the second preset current value, and the second current In is greater than the first preset current value, then it is determined that the direction of the first current Im is different from the direction of the second current In, including: obtaining the duration of time that the first current Im is less than the second preset current value, and the second current In is greater than the first preset current value; if the duration is greater than or equal to the first preset duration, then it is determined that the direction of the first current Im is different from the direction of the second current In.

[0048] It needs to be explained that if Figure 6As shown, when the conditions that the first current Im is less than the second preset current value and the second current In is greater than the first preset current value are met, it indicates that a fault has occurred, and the fault will trigger the timer to obtain the duration of the first current Im being less than the second preset current value and the second current In being greater than the first preset current value. The first preset duration can be 400us by way of example. When the duration, i.e., the fault trigger timing, is greater than or equal to 400us, it is determined that the direction of the first current Im is opposite to the direction of the second current In, and it is determined to be a bridge arm fault.

[0049] Optionally, based on a direction comparison result of the first current Im and the second current In, determining whether the bidirectional DC converter 10 is faulty includes: if the direction comparison result is that the direction of the first current Im is the same as the direction of the second current In, determining that the bidirectional DC converter 10 is normal.

[0050] It needs to be explained that if Figure 4 As shown, according to Figure 4 In the topological structure shown, under normal circumstances, when the bidirectional DC converter 10 is in the driving condition of the first mode, the directions of the first current Im and the second current In are both positive directions, and the first current Im is approximately equal to the second current In.

[0051] like Figure 5 As shown, according to Figure 5 In the topological structure shown, under normal circumstances, when the bidirectional DC converter 10 is in the power generation condition in the first mode, the directions of the first current Im and the second current In are both negative, and the first current Im is approximately equal to the second current In. It can be seen that when the direction of the first current Im is the same as the direction of the second current In, it can be determined that the bidirectional DC converter 10 is normal and no fault occurs.

[0052] Optionally, the direction comparison result is that the direction of the first current Im is the same as the direction of the second current In, including: determining whether the first current Im is greater than a first preset current value, and whether the second current In is less than or equal to the second preset current value; if not, determining whether the first current Im is less than the second preset current value, and whether the second current In is greater than the first preset current value; if not, determining whether the current difference is less than a third preset current value, and the current difference is equal to the difference between the first current Im and the second current In; if so, determining that the direction of the first current Im is the same as the direction of the second current In.

[0053] It needs to be explained that if Figure 6 As shown, the third preset current value can be exemplarily 20 A. The current difference value is abs (MN current difference). If the current difference value is greater than or equal to the third preset current value, the process ends.

[0054] Optionally, if so, determining that the direction of the first current Im is the same as the direction of the second current In includes: recording the duration during which the current difference is less than a third preset current value; if the duration is greater than or equal to the second preset duration, determining that the direction of the first current Im is the same as the direction of the second current In.

[0055] It needs to be explained that if Figure 6 As shown, the second preset duration can be exemplarily 200ms. If the current difference is less than the third preset current value, it means that the bridge arm is normal or the fault has been restored, and the counter timing will be triggered to obtain the specific value of the duration. The specific value of the duration is the fault recovery timing. In this way, it can be confirmed that the current is not reversed and the bridge arm is normal.

[0056] The first current Im can be detected by a first current sensor, and the second current In can be detected by a second current sensor.

[0057] Alternatively, if Figure 7 As shown, the fault detection method further includes: determining whether there is an open circuit fault in the lower bridge arm of the first bridge arm 11 and the second bridge arm 12 based on the voltage regulation target value and the output voltage of the bidirectional DC converter 10.

[0058] Optionally, based on the voltage regulation target value and the output voltage of the bidirectional DC converter 10, determining whether there is an open circuit fault in the lower bridge arm of the first bridge arm 11 and the second bridge arm 12 includes: judging whether the bidirectional DC converter 10 is in the first mode; if (Y), judging whether the voltage regulation target value (VCU) is less than the maximum boost value of the bidirectional DC converter 10; if so, judging whether the difference between the voltage regulation target value and the output voltage is greater than or equal to the voltage preset value; if so, determining that the boost of the bidirectional DC converter 10 is abnormal, so as to indicate that there is an open circuit fault in the lower bridge arm of the first bridge arm 11 and the second bridge arm 12.

[0059] The voltage preset value can be set according to actual conditions, for example, 100 V. The output voltage is the bus voltage, which can be detected by a voltage sensor and can be represented by U1 or U2.

[0060] The maximum boost value can be determined according to the parameters of the bidirectional DC converter 10, for example, the conduction time of the upper bridge arm and / or the lower bridge arm in the first bridge arm 11 and the second bridge arm 12, the inductance of the first inductor L1, the inductance of the second inductor L2, etc. The maximum boost value is the maximum output voltage that the bidirectional DC converter 10 can provide.

[0061] The voltage regulation target value can be determined according to the duty cycle of the driving signal connected to the bidirectional DC converter 10, and the driving signal is connected to the control end of the upper bridge arm and / or the lower bridge arm in the first bridge arm 11 and the second bridge arm 12, and is used to control the upper bridge arm and / or the lower bridge arm to be turned on or off. The voltage regulation target value is the voltage value expected to be output by the bidirectional DC converter 10.

[0062] Optionally, if so, it is determined that the bidirectional DC converter 10 has a boost abnormality to indicate that an open circuit fault exists in the lower bridge arm of the first bridge arm 11 and the second bridge arm 12, including: if so, recording the duration for which the difference between the voltage regulation target value and the output voltage is greater than or equal to the voltage preset value; if the duration is greater than or equal to a third preset duration, it is determined that the bidirectional DC converter 10 has a boost abnormality to indicate that an open circuit fault exists in the lower bridge arm of the first bridge arm 11 and the second bridge arm 12.

[0063] It should be noted that the third preset duration can be exemplarily 100ms. By recording the duration that the difference between the voltage regulation target value and the output voltage is greater than or equal to the voltage preset value, an open circuit fault may occur when the difference between the voltage regulation target value and the output voltage is greater than or equal to the voltage preset value, thereby triggering the timer to obtain the third preset duration, i.e., the fault trigger timing.

[0064] Optionally, if so, after determining whether the difference between the voltage regulation target value and the output voltage is greater than or equal to the voltage preset value, it also includes: if the difference between the voltage regulation target value and the output voltage is less than the voltage preset value, it is determined that the bidirectional DC converter 10 boosts the voltage normally, to indicate that the lower bridge arm of the first bridge arm 11 and the second bridge arm 12 is normal.

[0065] Optionally, if the difference between the voltage regulation target value and the output voltage is less than the voltage preset value, it is determined that the bidirectional DC converter 10 boosts the voltage normally, so as to indicate that the lower bridge arm of the first bridge arm 11 and the second bridge arm 12 is normal, including: if the difference between the voltage regulation target value and the output voltage is less than the voltage preset value, recording the duration during which the difference between the voltage regulation target value and the output voltage is less than the voltage preset value; judging whether the duration is greater than or equal to a fourth preset duration; if the duration is greater than or equal to the fourth preset duration, it is determined that the bidirectional DC converter 10 boosts the voltage normally, so as to indicate that the lower bridge arm of the first bridge arm 11 and the second bridge arm 12 is normal.

[0066] It should be noted that the fourth preset time length can be 200ms by way of example. When the difference between the voltage regulation target value and the output voltage is less than the voltage preset value, it is considered that no open circuit fault has occurred or the fault has been recovered, thereby triggering the timer to obtain the fourth preset time length, i.e., the fault recovery time.

[0067] In some of the embodiments, the present embodiment provides a fault detection circuit, which executes the above-mentioned fault detection method.

[0068] It can be understood that since the fault detection circuit of the embodiment of the present application executes the above-mentioned fault detection method, it is also possible to determine whether the first bridge arm 11 and / or the second bridge arm 12 are faulty by obtaining the first current Im flowing through the first inductor L1 and the second current In flowing through the second inductor L2 in the first mode, based on the direction comparison result of the first current Im and the second current In. This not only simplifies the fault detection process, but also avoids the situation where fault detection cannot be achieved due to the use of a driver chip because the desaturation detection function is not used to implement fault detection, thereby improving the reliability of fault detection.

[0069] In some of the embodiments, the present embodiment provides a storage medium storing a computer program, and the computer program implements the above-mentioned fault detection method when executed by a processor.

[0070] It can be understood that since the embodiment of the present application implements the above-mentioned fault detection method, it is also possible to determine whether the first bridge arm 11 and / or the second bridge arm 12 are faulty by obtaining the first current Im flowing through the first inductor L1 and the second current In flowing through the second inductor L2 in the first mode, based on the direction comparison result of the first current Im and the second current In. This not only simplifies the fault detection process, but also avoids the situation where fault detection cannot be achieved due to the use of a driver chip because the desaturation detection function is not used to implement fault detection, thereby improving the reliability of fault detection.

[0071] In some of the embodiments, the present embodiment provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, the above-mentioned fault detection method is implemented.

[0072] It can be understood that since the embodiment of the present application implements the above-mentioned fault detection method, it is also possible to determine whether the first bridge arm 11 and / or the second bridge arm 12 are faulty by obtaining the first current Im flowing through the first inductor L1 and the second current In flowing through the second inductor L2 in the first mode, based on the direction comparison result of the first current Im and the second current In. This not only simplifies the fault detection process, but also avoids the situation where fault detection cannot be achieved due to the use of a driver chip because the desaturation detection function is not used to implement fault detection, thereby improving the reliability of fault detection.

[0073] In some of the embodiments, the present embodiment provides an electronic device, which includes the above-mentioned fault detection circuit, or the electronic device includes the above-mentioned storage medium.

[0074] It can be understood that since the electronic device of the embodiment of the present application includes the above-mentioned fault detection circuit or storage medium, it is also possible to determine whether the first bridge arm 11 and / or the second bridge arm 12 are faulty by obtaining the first current Im flowing through the first inductor L1 and the second current In flowing through the second inductor L2 in the first mode, based on the direction comparison result of the first current Im and the second current In. This not only simplifies the fault detection process, but also avoids the situation where fault detection cannot be achieved due to the use of a driver chip because the desaturation detection function is not used to implement fault detection, thereby improving the reliability of fault detection.

[0075] In some of the embodiments, the present embodiment provides a controller, which includes a memory and a processor, wherein a computer program is stored in the memory; the processor is used to execute the computer program in the memory to implement the above-mentioned fault detection method.

[0076] It can be understood that since the embodiment of the present application implements the above-mentioned fault detection method, it is also possible to determine whether the first bridge arm 11 and / or the second bridge arm 12 are faulty by obtaining the first current Im flowing through the first inductor L1 and the second current In flowing through the second inductor L2 in the first mode, based on the direction comparison result of the first current Im and the second current In. This not only simplifies the fault detection process, but also avoids the situation where fault detection cannot be achieved due to the use of a driver chip because the desaturation detection function is not used to implement fault detection, thereby improving the reliability of fault detection.

[0077] In some of the embodiments, the present embodiment provides a vehicle comprising the electronic device or controller described above.

[0078] It can be understood that since the embodiment of the present application implements the above-mentioned fault detection method, it is also possible to determine whether the first bridge arm 11 and / or the second bridge arm 12 are faulty by obtaining the first current Im flowing through the first inductor L1 and the second current In flowing through the second inductor L2 in the first mode, based on the direction comparison result of the first current Im and the second current In. This not only simplifies the fault detection process, but also avoids the situation where fault detection cannot be achieved due to the use of a driver chip because the desaturation detection function is not used to implement fault detection, thereby improving the reliability of fault detection.

[0079] In the description of this application, 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 technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0080] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0081] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0082] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A fault detection method, characterized in that: The fault detection method is applied to a bidirectional DC converter; The bidirectional DC converter includes a first inductor and a second inductor; The bidirectional DC converter further comprises a first bridge arm connected to the first inductor and a second bridge arm connected to the second inductor, wherein the first bridge arm is connected in parallel with the second bridge arm; The fault detection method comprises: Acquire a first current flowing through the first inductor and a second current flowing through the second inductor in a first mode; Based on a result of comparing the directions of the first current and the second current, it is determined whether the first bridge arm and / or the second bridge arm is faulty.

2. The fault detection method according to claim 1, characterized in that: The determining whether the first bridge arm and / or the second bridge arm is faulty based on a result of comparing the directions of the first current and the second current includes: If the direction comparison result is that the direction of the first current is different from the direction of the second current, it is determined that the first bridge arm and / or the second bridge arm is faulty.

3. The fault detection method according to claim 2, characterized in that: The direction comparison result is that the direction of the first current is different from the direction of the second current, including: Determining whether the first current is greater than a first preset current value, and whether the second current is less than a second preset current value; If the first current is greater than the first preset current value and the second current is less than the second preset current value, it is determined that the direction of the first current is different from the direction of the second current.

4. The fault detection method according to claim 3, characterized in that: If the first current is greater than the first preset current value, and the second current is less than the second preset current value, determining that the direction of the first current is different from the direction of the second current includes: Obtaining a duration during which the first current is greater than the first preset current value and the second current is less than the second preset current value; If the duration is greater than or equal to a first preset duration, it is determined that the direction of the first current is different from the direction of the second current.

5. The fault detection method according to claim 3, characterized in that: After determining whether the first current is greater than a first preset current value and whether the second current is less than or equal to a second preset current value, the method further includes: If the first current is less than a first preset current value, and the second current is greater than a second preset current value, determining whether the first current is less than the second preset current value, and whether the second current is greater than the first preset current value; If it is determined that the first current is less than the second preset current value, and the second current is greater than the first preset current value, it is determined that the direction of the first current is different from the direction of the second current.

6. The fault detection method according to claim 5, characterized in that: If it is determined that the first current is less than the second preset current value and the second current is greater than the first preset current value, determining that the direction of the first current is different from the direction of the second current includes: Obtaining a duration during which the first current is less than the second preset current value and the second current is greater than the first preset current value; If the duration is greater than or equal to a first preset duration, it is determined that the direction of the first current is different from the direction of the second current.

7. The fault detection method according to claim 1, characterized in that: The determining whether the first bridge arm and / or the second bridge arm is faulty based on a result of comparing the directions of the first current and the second current includes: If the direction comparison result is that the direction of the first current is the same as the direction of the second current, it is determined that the first bridge arm and / or the second bridge arm is normal.

8. The fault detection method according to claim 7, characterized in that: The direction comparison result is that the direction of the first current is the same as the direction of the second current, including: Determining whether the first current is greater than a first preset current value, and whether the second current is less than a second preset current value; If not, determining whether the first current is less than the second preset current value, and whether the second current is greater than the first preset current value; If not, determining whether the current difference is less than a third preset current value, the current difference being equal to the difference between the first current and the second current; If so, it is determined that the direction of the first current is the same as the direction of the second current.

9. The fault detection method according to claim 8, characterized in that: If yes, determining that the direction of the first current is the same as the direction of the second current includes: Recording the duration of time during which the current difference is less than the third preset current value; If the duration is greater than or equal to a second preset duration, it is determined that the direction of the first current is the same as the direction of the second current.

10. The fault detection method according to claim 8, characterized in that: The obtaining a first current flowing through the first inductor and a second current flowing through the second inductor in the first mode includes: Detecting the first current by a first current sensor; The second current is detected by a second current sensor.

11. The fault detection method according to any one of claims 1 to 10, characterized in that: The fault detection method further comprises: Based on the voltage regulation target value and the output voltage of the bidirectional DC converter, it is determined whether an open circuit fault occurs in a lower bridge arm of the first bridge arm and / or the second bridge arm.

12. The fault detection method according to claim 11, characterized in that: The determining whether there is an open circuit fault in the lower bridge arm of the first bridge arm and the second bridge arm based on the voltage regulation target value and the output voltage of the bidirectional DC converter includes: determining whether the bidirectional DC converter is in a first mode; If so, determining whether the voltage regulation target value is less than the maximum boost value of the bidirectional DC converter; If so, determining whether the difference between the voltage regulation target value and the output voltage is greater than or equal to a voltage preset value; If so, it is determined that an open circuit fault exists in the lower bridge arm of the first bridge arm and / or the second bridge arm.

13. The fault detection method according to claim 12, characterized in that: If yes, determining that an open circuit fault exists in the lower bridge arm of the first bridge arm and / or the second bridge arm includes: If the difference between the voltage regulation target value and the output voltage is greater than or equal to the voltage preset value, record the duration for which the difference between the voltage regulation target value and the output voltage is greater than or equal to the voltage preset value; If the duration is greater than or equal to a third preset duration, it is determined that an open circuit fault exists in the lower bridge arm of the first bridge arm and / or the second bridge arm.

14. The fault detection method according to claim 12, characterized in that: If yes, after determining whether the difference between the voltage regulation target value and the output voltage is greater than or equal to the voltage preset value, the method further includes: If the difference between the voltage regulation target value and the output voltage is smaller than the preset voltage value, it is determined that the lower bridge arm in the first bridge arm and / or the second bridge arm is normal.

15. The fault detection method according to claim 14, characterized in that: If the difference between the voltage regulation target value and the output voltage is less than the preset voltage value, determining that the lower bridge arm in the first bridge arm and / or the second bridge arm is normal includes: If the difference between the voltage regulation target value and the output voltage is less than the preset voltage value, record the duration of the difference between the voltage regulation target value and the output voltage being less than the preset voltage value; Determining whether the duration is greater than or equal to a fourth preset duration; If the duration is greater than or equal to the fourth preset duration, it is determined that the lower bridge arm of the first bridge arm and / or the second bridge arm is normal.

16. The fault detection method according to claim 12, characterized in that: The fault detection method further comprises: Determining the maximum boost value according to the parameters of the bidirectional DC converter; Determining a voltage regulation target value according to a duty cycle of a drive signal connected to the bidirectional DC converter; The output voltage is detected by a voltage sensor.

17. A fault detection circuit, characterized in that: The fault detection circuit executes the fault detection method as described in any one of claims 1-16.

18. A storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the fault detection method according to any one of claims 1 to 16 is implemented.

19. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the fault detection method according to any one of claims 1 to 16 is implemented.

20. An electronic device, characterized in that: The electronic device comprises the fault detection circuit according to claim 17, or the electronic device comprises the storage medium according to claim 18, or the electronic device comprises the computer program product according to claim 19.

21. A controller, characterized in that: The controller comprises: A memory having a computer program stored therein; A processor, configured to execute the computer program in the memory to implement the fault detection method according to any one of claims 1 to 16.

22. A vehicle, characterized in that: The vehicle includes the electronic device as claimed in claim 20, or the vehicle includes the controller as claimed in claim 21.

Images