DC conversion circuit, switch control method, controller and vehicle

Abstract

The invention relates to a direct-current conversion circuit, a switch control method, a controller and a vehicle, the direct-current conversion circuit comprises a first energy storage module, a second energy storage module and a switch module, and the switch module is controlled to be switched on under the condition that the voltage difference between the two ends of the switch module is smaller than a first voltage threshold value. The voltage difference between the first energy storage module and the second energy storage module, namely the voltage difference between the two ends, can be reduced, so that instantaneous large current flowing through the switch module can be avoided, and the interference phenomenon is improved.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to a direct current conversion circuit, a switch control method, a controller and a vehicle. Background Art

[0002] A DC conversion circuit (DC / DC conversion circuit) is an electronic circuit that converts one DC voltage into another DC voltage.

[0003] Among them, the DC conversion circuit usually uses some energy storage elements, which will cause instantaneous large current in some cases and cause unnecessary interference to the outside. Summary of the invention

[0004] The embodiments of the present application provide a DC conversion circuit, a switch control method, a controller and a vehicle, which reduce instantaneous large currents and improve interference phenomena.

[0005] In order to achieve the above-mentioned purpose, according to the first aspect of the present application, there is provided a DC conversion circuit, comprising a first energy storage module, a second energy storage module and a switch module, wherein the first energy storage module and the second energy storage module are both arranged at the output end of the DC conversion module; the switch module is connected to the first energy storage module and the second energy storage module so as to be controlled to be turned on when the voltage difference between the two ends of the switch module is less than a first voltage threshold.

[0006] Optionally, the DC conversion circuit also includes a DC conversion module and a drive control module. The DC conversion module is connected to the first energy storage module, and the DC conversion module is used to convert the DC input voltage into a corresponding DC output voltage; the drive control module is connected to the switch module, and the drive control module is used to control the switch module to be turned on when the voltage difference between the two ends of the switch module is less than the first voltage threshold.

[0007] Optionally, the drive control module is further configured to control the switch module to disconnect when a short circuit occurs in the DC conversion module.

[0008] Optionally, when the potential of at least one of the two ends of the switch module is less than the second voltage threshold and the current flowing through the switch module is greater than the current threshold, the short circuit judgment result is that the DC conversion module is in a short circuit state.

[0009] Optionally, the drive control module is further configured to control the switch module to turn on after the voltage difference between the two ends is greater than or equal to the first voltage threshold for a preset period of time when the DC conversion module is in a normal state.

[0010] Optionally, the switch module includes a first switch tube or multiple first switch tubes connected in parallel, the first pole of the first switch tube is connected to the other end of the first energy storage module, the second pole of the first switch tube is connected to the other end of the second energy storage module, and the control pole of the first switch tube is connected to the output end of the drive control module.

[0011] Optionally, the first energy storage module includes a first capacitor, the second energy storage module includes a second capacitor, one end of the first capacitor is connected to one end of the second capacitor, the other end of the first capacitor is connected to the first pole of the first switching tube, and the other end of the second capacitor is connected to the second pole of the first switching tube.

[0012] Optionally, the drive control module includes a pressure difference calculation unit, a comparison unit and a drive unit, an input end of the pressure difference calculation unit is connected to one end of the switch module and the first energy storage module, the other input end of the pressure difference calculation unit is connected to the other end of the switch module and the second energy storage module, and the pressure difference calculation unit is used to calculate the pressure difference between the two ends of the switch module; the comparison unit is connected to the output end of the pressure difference calculation unit, and the comparison unit is used to compare the pressure difference between the two ends with the size of the first voltage threshold; the drive unit is connected to the comparison unit and the switch module, and the drive unit is used to control the switch module to be turned on when the pressure difference between the two ends is less than the first voltage threshold.

[0013] Optionally, the drive control module also includes a short-circuit judgment unit, which is connected to the switch module and the drive unit. The short-circuit judgment unit is used to obtain a short-circuit judgment result of the DC conversion module based on the potential of at least one of the two ends of the switch module and the current flowing through the switch module.

[0014] Optionally, the drive control module also includes a timing unit, which is connected to the drive unit and is used to calculate the duration that the voltage difference between the two ends is greater than or equal to the first voltage threshold; when the duration is greater than the preset duration, the timing unit controls the switch module to turn on through the drive unit.

[0015] According to a second aspect of the present application, a switch control method is provided, which is applied to the above-mentioned DC conversion circuit. The switch control method includes: judging the relationship between the voltage difference between the two ends of the switch module and the first voltage threshold; when the voltage difference between the two ends is less than the first voltage threshold, controlling the switch module to be turned on.

[0016] Optionally, the switch control method further includes: determining whether a short circuit occurs in the DC conversion module; and controlling the switch module to be disconnected when a short circuit occurs in the DC conversion module.

[0017] Optionally, the switch control method further includes: when the DC conversion module is not short-circuited, calculating the duration of time that the voltage difference between the two ends is greater than or equal to the first voltage threshold; when the duration is greater than a preset duration, controlling the switch module to turn on.

[0018] Optionally, determining the magnitude relationship between the voltage difference across the switch module and the first voltage threshold includes: calculating the voltage difference across the switch module; and comparing the magnitude relationship between the voltage difference across the switch module and the first voltage threshold.

[0019] According to a third aspect of the present application, a controller is provided, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the above-mentioned switch control method when executing the computer program.

[0020] According to a fourth aspect of the present application, a vehicle is provided, which includes the above-mentioned DC conversion circuit or controller.

[0021] The DC conversion circuit, switch control method, controller and vehicle of the embodiments of the present application can reduce the voltage difference between the first energy storage module and the second energy storage module, i.e., the voltage difference between the two ends, by controlling the switch module to be turned on when the voltage difference between the two ends of the switch module is less than the first voltage threshold, thereby avoiding the occurrence of instantaneous large current in the current flowing through the switch module and improving interference.

[0022] Furthermore, by adding a switch module, when the potential of the other end of the switch module is higher than the potential of one end of the switch module, current can be prevented from flowing back from the other end of the switch module to one end of the switch module. In other words, the switch module can also prevent current from flowing back.

[0023] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] 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.

[0025] 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.

[0026] Figure 1 is a principle block diagram of a DC conversion circuit provided in an exemplary embodiment of the present disclosure;

[0027] Figure 2 is a first principle block diagram of a drive control module provided in an exemplary embodiment of the present disclosure;

[0028] Figure 3is a second principle block diagram of a drive control module provided in an exemplary embodiment of the present disclosure;

[0029] Figure 4 is a third principle block diagram of a drive control module provided in an exemplary embodiment of the present disclosure;

[0030] Figure 5 is a circuit schematic diagram of a DC conversion circuit provided in an exemplary embodiment of the present disclosure;

[0031] Figure 6 is another circuit schematic diagram of a switch module provided in an exemplary embodiment of the present disclosure;

[0032] Figure 7 is a flow chart of a switch control method provided in an exemplary embodiment of the present disclosure.

[0033] Description of reference numerals:

[0034] 100. DC conversion circuit;

[0035] 10. DC conversion module;

[0036] 20. A first energy storage module;

[0037] 30. A second energy storage module;

[0038] 40. Switch module;

[0039] 50. Drive control module; 51. Pressure difference calculation unit; 52. Comparison unit; 53. Drive unit; 54. Short circuit judgment unit; 55. Timing unit. DETAILED DESCRIPTION

[0040] 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.

[0041] The present application provides a DC conversion circuit 100. Figures 1 to 7 ,like Figure 1 As shown, the DC conversion circuit 100 includes a first energy storage module 20, a second energy storage module 30 and a switch module 40. The first energy storage module 20 and the second energy storage module 30 are both arranged at the output end of the DC conversion module 10. The switch module 40 is connected between the first energy storage module 20 and the second energy storage module 30 so as to be controlled to be turned on when the voltage difference between the two ends of the switch module 40 is less than the first voltage threshold.

[0042] It can be understood that the DC conversion circuit 100 of the embodiment of the present application can reduce the voltage difference between the first energy storage module 20 and the second energy storage module 30, that is, the voltage difference between the two ends, by controlling the switch module 40 to be turned on when the voltage difference between the two ends of the switch module 40 is less than the first voltage threshold, thereby avoiding the occurrence of instantaneous large current in the current flowing through the switch module 40 and improving the interference phenomenon.

[0043] Furthermore, by adding the switch module 40, when the potential at the other end of the switch module 40 is higher than the potential at one end of the switch module 40, current can be prevented from flowing back from the other end of the switch module 40 to one end of the switch module 40. That is, the switch module 40 can also prevent current from flowing back.

[0044] It should be noted that one end of the second energy storage module 30 is connected to one end of the first energy storage module 20 ; one end of the switch module 40 is connected to the other end of the first energy storage module 20 , and the other end of the switch module 40 is connected to the other end of the second energy storage module 30 .

[0045] In one embodiment, if Figure 1 As shown, the DC conversion circuit 100 includes a DC conversion module 10 and a drive control module 50. The DC conversion module 10 is connected to the first energy storage module 20, and the DC conversion module 10 is used to convert the DC input voltage into the corresponding DC output voltage; the drive control module 50 is connected to the switch module 40, and the drive control module 50 is used to control the switch module 40 to be turned on when the voltage difference between the two ends of the switch module 40 is less than the first voltage threshold.

[0046] It should be noted that, compared with the need to configure a corresponding pre-charging circuit for the first energy storage module 20 separately, the present application can reuse the DC conversion module 10 to pre-charge the first energy storage module 20 when the switch module 40 is disconnected, thereby saving the pre-charging circuit and reducing the cost and design complexity.

[0047] In one embodiment, if Figure 2 As shown, the drive control module 50 includes a pressure difference calculation unit 51, a comparison unit 52 and a drive unit 53. One input end of the pressure difference calculation unit 51 is connected to one end of the switch module 40, and the other input end of the pressure difference calculation unit 51 is connected to the other end of the switch module 40. The pressure difference calculation unit 51 is used to calculate the pressure difference between the two ends of the switch module 40; the comparison unit 52 is connected to the output end of the pressure difference calculation unit 51, and the comparison unit 52 is used to compare the pressure difference between the two ends with the first voltage threshold; the drive unit 53 is connected to the comparison unit 52 and the switch module 40, and the drive unit 53 is used to control the switch module 40 to be turned on when the pressure difference between the two ends is less than the first voltage threshold.

[0048] It should be noted that the pressure difference calculation unit 51 can be connected to both ends of the switch module 40 to detect the potentials at both ends of the switch module 40 in real time, and then obtain the pressure difference at both ends of the switch module 40 according to the difference between the potentials at both ends. One input end of the comparison unit 52 is connected to the pressure difference at both ends, and the other end of the comparison unit 52 is connected to the first voltage threshold, and then the driving unit 53 is controlled according to the comparison result of the pressure difference at both ends and the first voltage threshold.

[0049] It is understandable that the first voltage threshold can be used to limit the maximum instantaneous current flowing through the switch module 40. The larger the first voltage threshold, the larger the maximum instantaneous current allowed; conversely, the smaller the first voltage threshold, the smaller the maximum instantaneous current allowed. In order to reduce the instantaneous current flowing through the switch module 40 and reduce the pre-charging time of the first energy storage module 20, the first voltage threshold can be exemplarily set to 1V, 1.5V, 2V, 2.5V or 3V, etc.

[0050] In one embodiment, the driving control module 50 is further configured to control the switch module 40 to be disconnected when a short circuit occurs in the DC conversion module 10 .

[0051] It should be noted that, when a short circuit occurs in the DC conversion module 10 , the drive control module 50 can control the switch module 40 to be disconnected, thereby realizing a short circuit protection function.

[0052] In one embodiment, if Figure 3 As shown, the drive control module 50 also includes a short-circuit judgment unit 54, which is connected to the switch module 40 and the drive unit 53. The short-circuit judgment unit 54 is used to obtain a short-circuit judgment result of the DC conversion module 10 based on the potential of at least one of the two ends of the switch module 40 and the current flowing through the switch module 40.

[0053] It should be noted that the current flowing through the switch module 40 can be measured based on the shunt plug or the Hall sensor. When the potential of at least one of the two ends of the switch module 40 is less than the second voltage threshold, and the current flowing through the switch module 40 is greater than the current threshold, the short-circuit judgment result is that the DC conversion module 10 is in a short-circuit state; when the potential of at least one of the two ends of the switch module 40 is greater than or equal to the second voltage threshold, and the current flowing through the switch module 40 is less than or equal to the current threshold, the short-circuit judgment result is that the DC conversion module 10 is in a normal state. Among them, the second voltage threshold can be set according to the specific structure of the DC conversion module 10 to obtain a more accurate short-circuit judgment result.

[0054] In one embodiment, if Figure 4As shown, the drive control module 50 is also used to control the switch module 40 to turn on when the DC conversion module 10 is in a normal state and the voltage difference between the two ends is greater than or equal to the first voltage threshold for a preset period of time.

[0055] It should be noted that, in this embodiment, when the DC conversion module 10 is not short-circuited, after the voltage difference between the two ends is greater than or equal to the first voltage threshold for a preset period of time, the switch module 40 is controlled to be turned on, which can avoid the situation where the switch module 40 cannot be turned on due to the error in the sampling result of the potential between the two ends of the switch module 40. This not only reduces the cost, but also ensures the safety of the circuit.

[0056] The longer the preset time is, the higher the safety is; the shorter the preset time is, the higher the working efficiency of the DC conversion circuit is. Based on this, the range of the preset time can be 0.5 seconds to 10 seconds, such as 1 second, 2 seconds, 3 seconds, 4 seconds or 5 seconds.

[0057] In one embodiment, if Figure 4 As shown, the drive control module 50 also includes a timing unit 55, which is connected to the drive unit 53. The timing unit 55 is used to calculate the duration of time that the voltage difference between the two ends is greater than or equal to the first voltage threshold; when the duration is greater than the preset duration, the timing unit 55 controls the switch module 40 to turn on through the drive unit 53.

[0058] It should be noted that, when the duration is less than or equal to the preset duration, it is continued to be determined whether the voltage difference between the two ends is less than the first voltage threshold.

[0059] In one embodiment, if Figure 5 As shown, the first energy storage module 20 includes a first capacitor C1, and the second energy storage module 30 includes a second capacitor C2. One end of the first capacitor C1 is connected to one end of the second capacitor C2, the other end of the first capacitor C1 is connected to the first electrode of the first switch tube M1, and the other end of the second capacitor C2 is connected to the second electrode of the first switch tube M1.

[0060] It should be noted that, in other embodiments, the first energy storage module 20 or the second energy storage module 30 may also be at least two capacitors and / or at least one inductor.

[0061] In one embodiment, if Figure 5 , Figure 6As shown, the switch module 40 includes a first switch tube M1 or multiple first switch tubes M1 connected in parallel, the first pole of the first switch tube M1 is connected to the other end of the first energy storage module 20, the second pole of the first switch tube M1 is connected to the other end of the second energy storage module 30, and the control pole of the first switch tube M1 is connected to the output end of the drive control module 50.

[0062] It should be noted that the first switch tube M1 may be a field effect switch tube or a bipolar junction switch tube. Figure 5 , Figure 6 In the example, a P-channel switch tube is used, and in other embodiments, an N-channel switch tube may also be used.

[0063] For a field effect switch, the first electrode may be one of the source and the drain, the second electrode may be the other of the source and the drain, and the control electrode may be the gate. For a bipolar junction switch, the first electrode may be one of the emitter and the collector, the second electrode may be the other of the emitter and the collector, and the control electrode may be the base.

[0064] In one embodiment, if Figure 5 As shown, the DC conversion module 10 includes a third capacitor C3, a second switch tube Q1, a third switch tube Q2, a fourth switch tube Q3, a fifth switch tube Q4, a sixth switch tube Q5, a seventh switch tube Q6, a transformer T1 and a first inductor L1.

[0065] The second switch tube Q1, the third switch tube Q2, the fourth switch tube Q3 and the fifth switch tube Q4 constitute an inverter, and the sixth switch tube Q5 and the seventh switch tube Q6 constitute a full-wave rectification circuit.

[0066] The third capacitor C3 is connected in parallel to the input end of the inverter and connected to the DC voltage. The output end of the inverter is connected to the primary side of the transformer T1. The two ends of the secondary side of the transformer T1 are respectively connected to the sixth switch tube Q5 and the seventh switch tube Q6. The middle tap of the secondary side of the transformer T1 is connected to the first energy storage module 20 through the first inductor L1.

[0067] In one embodiment, if Figure 5 As shown, the DC conversion module 10 further includes a power filter 11, and the power filter 11 is used to filter the connected DC voltage.

[0068] In one embodiment, if Figure 5 As shown, the DC conversion module 10 further includes a fuse F1, and the fuse F1 is used to improve the safety of the circuit.

[0069] The above-mentioned DC conversion module 10 is a hard-switch full-bridge structure, which adopts duty cycle control. The second switch tube Q1 and the fifth switch tube Q4 are turned on at the same time, and the third switch tube Q2 and the fourth switch tube Q3 are turned on at the same time. The duty cycle of the third switch tube Q2 lags behind the second switch tube Q1 by 180°. The duty cycle adjustment range is 0-50%. The larger the duty cycle, the higher the output voltage.

[0070] The embodiment of the present application provides a switch control method, which is applied to the above-mentioned DC conversion circuit 100. The switch control method includes the following steps:

[0071] The relationship between the voltage difference across the switch module 40 and the first voltage threshold is determined.

[0072] When the voltage difference between the two ends is less than the first voltage threshold, the switch module 40 is controlled to be turned on.

[0073] It can be understood that the switch control method of the embodiment of the present application can reduce the voltage difference between the first energy storage module 20 and the second energy storage module 30, that is, the voltage difference between the two ends, by controlling the switch module 40 to be turned on when the voltage difference between the two ends of the switch module 40 is less than the first voltage threshold, thereby avoiding the occurrence of instantaneous large current in the current flowing through the switch module 40 and improving the interference phenomenon.

[0074] Furthermore, by adding the switch module 40, when the potential at the other end of the switch module 40 is higher than the potential at one end of the switch module 40, current can be prevented from flowing back from the other end of the switch module 40 to one end of the switch module 40. That is, the switch module 40 can also prevent current from flowing back.

[0075] It should be noted that determining the magnitude relationship between the voltage difference between the two ends of the switch module 40 and the first voltage threshold includes the following steps:

[0076] The voltage difference between both ends of the switch module 40 is calculated.

[0077] The magnitude relationship between the voltage difference between the two ends and the first voltage threshold is compared.

[0078] In one embodiment, the switch control method further includes the following steps:

[0079] It is determined whether the DC conversion module 10 is short-circuited.

[0080] When a short circuit occurs in the DC conversion module 10 , the switch module 40 is controlled to be disconnected.

[0081] In one embodiment, the switch control method further includes the following steps:

[0082] When the DC conversion module 10 is not short-circuited, the duration during which the voltage difference between the two ends is greater than or equal to the first voltage threshold is calculated.

[0083] When the duration is longer than the preset duration, the switch module 40 is controlled to be turned on.

[0084] like Figure 7 As shown, the above switch control method is specifically as follows:

[0085] Start: One of the scenarios starts with power on.

[0086] Detecting the pressure difference between the two ends: that is, detecting the pressure difference between the two ends of the switch module 40 .

[0087] Voltage difference between the two ends <2V: Determine whether the voltage difference between the two ends is less than 2V.

[0088] The switch module 40 is turned on: when the voltage difference between the two ends is less than 2V, the switch module 40 is controlled to be turned on.

[0089] Determine whether there is a short circuit: When the voltage difference between the two ends is greater than or equal to 2V, determine whether the DC conversion module 10 is short-circuited.

[0090] The switch module 40 is turned off: when a short circuit occurs in the DC conversion module 10 , the switch module 40 is controlled to be turned off.

[0091] Timing <3S (seconds): When the DC conversion module 10 is not short-circuited and the voltage difference between the two ends is greater than or equal to the first voltage threshold for a duration greater than 3S, the switch module 40 is controlled to be turned on. Alternatively, when the DC conversion module 10 is not short-circuited and the voltage difference between the two ends is greater than or equal to the first voltage threshold for a duration less than or equal to 3S, it is continued to be determined whether the voltage difference between the two ends is less than 2V.

[0092] In some embodiments, when the voltage difference between the two ends is greater than or equal to a first voltage threshold (eg, 2V), the switch module 40 can be controlled to be disconnected to avoid an instantaneous large current.

[0093] In some embodiments, when the voltage difference between the two ends is greater than or equal to a first voltage threshold (eg, 2V) and the DC conversion module 10 is short-circuited, the switch module 40 is controlled to be disconnected to avoid instantaneous high current and implement short-circuit protection.

[0094] An embodiment of the present application provides a controller, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the above-mentioned switch control method is implemented.

[0095] It can be understood that the switch control method of the embodiment of the present application can reduce the voltage difference between the first energy storage module 20 and the second energy storage module 30, that is, the voltage difference between the two ends, by controlling the switch module 40 to be turned on when the voltage difference between the two ends of the switch module 40 is less than the first voltage threshold, thereby avoiding the occurrence of instantaneous large current in the current flowing through the switch module 40 and improving the interference phenomenon.

[0096] Furthermore, by adding the switch module 40, when the potential at the other end of the switch module 40 is higher than the potential at one end of the switch module 40, current can be prevented from flowing back from the other end of the switch module 40 to one end of the switch module 40. That is, the switch module 40 can also prevent current from flowing back.

[0097] The embodiment of the present application provides a vehicle, which includes the above-mentioned DC conversion circuit 100. It can be understood that since the vehicle of the embodiment of the present application includes the DC conversion circuit 100, the voltage difference between the first energy storage module 20 and the second energy storage module 30, i.e., the voltage difference between the two ends, can be reduced by controlling the switch module 40 to be turned on when the voltage difference between the two ends of the switch module 40 is less than the first voltage threshold, thereby avoiding the instantaneous large current flowing through the switch module 40 and improving the interference phenomenon.

[0098] Furthermore, by adding the switch module 40, when the potential at the other end of the switch module 40 is higher than the potential at one end of the switch module 40, current can be prevented from flowing back from the other end of the switch module 40 to one end of the switch module 40. That is, the switch module 40 can also prevent current from flowing back.

[0099] 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.

[0100] 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.

[0101] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0102] 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 DC conversion circuit, characterized in that: The DC conversion circuit comprises: A first energy storage module and a second energy storage module, wherein the first energy storage module and the second energy storage module are both arranged at an output end of a DC conversion module; A switch module is connected between the first energy storage module and the second energy storage module to be controlled to be turned on when the voltage difference between the two ends of the switch module is less than a first voltage threshold.

2. The DC conversion circuit according to claim 1, characterized in that: The DC conversion circuit also includes: A DC conversion module, the DC conversion module is connected to the first energy storage module, and the DC conversion module is used to convert a DC input voltage into a corresponding DC output voltage; A drive control module is connected to the switch module, and is used to control the switch module to conduct when the voltage difference between the two ends of the switch module is less than a first voltage threshold.

3. The DC conversion circuit according to claim 2, characterized in that: The drive control module is also used to control the switch module to disconnect when a short circuit occurs in the DC conversion module.

4. The DC conversion circuit according to claim 3, characterized in that: When the potential of at least one of the two ends of the switch module is less than the second voltage threshold and the current flowing through the switch module is greater than the current threshold, the short circuit judgment result is that the DC conversion module is in a short circuit state.

5. The DC conversion circuit according to claim 2, characterized in that: The drive control module is also used to control the switch module to turn on after the DC conversion module is in a normal state and the voltage difference between the two ends is greater than or equal to the first voltage threshold for a preset period of time.

6. The DC conversion circuit according to any one of claims 1 to 5, characterized in that: The switch module includes a first switch tube or multiple first switch tubes connected in parallel, the first pole of the first switch tube is connected to the other end of the first energy storage module, the second pole of the first switch tube is connected to the other end of the second energy storage module, and the control pole of the first switch tube is connected to the output end of the drive control module.

7. The DC conversion circuit according to claim 6, characterized in that: The first energy storage module includes a first capacitor, the second energy storage module includes a second capacitor, one end of the first capacitor is connected to one end of the second capacitor, the other end of the first capacitor is connected to the first electrode of the first switch tube, and the other end of the second capacitor is connected to the second electrode of the first switch tube.

8. The DC conversion circuit according to claim 2, characterized in that: The drive control module comprises: a pressure difference calculation unit, wherein one input end of the pressure difference calculation unit is connected to one end of the switch module and the first energy storage module, and the other input end of the pressure difference calculation unit is connected to the other end of the switch module and the second energy storage module, and the pressure difference calculation unit is used to calculate the pressure difference between the two ends of the switch module; A comparison unit, the comparison unit is connected to the output end of the voltage difference calculation unit, and the comparison unit is used to compare the voltage difference between the two ends with the first voltage threshold; A driving unit, wherein the driving unit is connected to the comparing unit and the switching module, and the driving unit is used to control the switching module to be turned on when the voltage difference between the two ends is less than the first voltage threshold.

9. The DC conversion circuit according to claim 8, characterized in that: The drive control module also includes a short-circuit judgment unit, which is connected to the switch module and the drive unit. The short-circuit judgment unit is used to obtain a short-circuit judgment result of the DC conversion module based on the potential of at least one of the two ends of the switch module and the current flowing through the switch module.

10. The DC conversion circuit according to claim 9, characterized in that: The driving control module further includes a timing unit, which is connected to the driving unit and is used to calculate the duration of time during which the voltage difference between the two ends is greater than or equal to the first voltage threshold; When the duration is greater than the preset duration, the timing unit controls the switch module to be turned on through the driving unit.

11. A switch control method, characterized in that: The switch control method is applied to the DC conversion circuit according to any one of claims 1 to 10, and the switch control method comprises: Determine the magnitude relationship between the voltage difference between the two ends of the switch module and the first voltage threshold; When the voltage difference between the two ends is less than the first voltage threshold, the switch module is controlled to be turned on.

12. The switch control method according to claim 11, characterized in that: The switch control method further includes: Determining whether the DC conversion module is short-circuited; When a short circuit occurs in the DC conversion module, the switch module is controlled to be disconnected.

13. The switch control method according to claim 12, characterized in that: The switch control method further includes: When the DC conversion module is not short-circuited, calculating the duration of time during which the voltage difference between the two ends is greater than or equal to the first voltage threshold; When the duration is longer than a preset duration, the switch module is controlled to be turned on.

14. The switch control method according to claim 11, characterized in that: The determining of the relationship between the voltage difference between the two ends of the switch module and the first voltage threshold includes: Calculating the pressure difference between the two ends of the switch module; The magnitude relationship between the voltage difference between the two ends and the first voltage threshold is compared.

15. A controller, characterized in that: The controller includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the switch control method according to any one of claims 11 to 14 is implemented.

16. A vehicle, characterized in that: The vehicle includes the DC conversion circuit as claimed in any one of claims 1 to 10, or includes the controller as claimed in claim 15.

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