Protection circuit, battery management system and electric device

Abstract

The utility model discloses a protection circuit, a battery management system and an electric device. The protection circuit comprises a detection module and a control module, the detection module is connected with a power supply and the control module, the control module is connected with a power utilization circuit, and the power utilization circuit comprises a power supply processor and a load. The detection module is used for detecting the voltage of the power supply, the control module is used for controlling the load to be in a turn-off state when the voltage of the power supply is within a preset voltage range, and the minimum voltage of the preset voltage range is smaller than the normal working voltage of the power supply processor. The maximum voltage of the preset voltage range is greater than or equal to the normal working voltage of the power processor. According to the embodiment of the invention, the load can be controlled to be in a turn-off state under the condition that the power supply voltage is under-voltage, so that the problem that the load state is out of control during under-voltage is solved.

Description

Technical Field

[0001] The present application relates to the technical field of undervoltage protection, and in particular to a protection circuit, a battery management system and an electrical device. Background Art

[0002] The drive control module may be used to control the state of the load, and the drive control module may include some chips.

[0003] However, the normal operating voltage range of the chip is limited. For example, the power processor chip in the drive control module can only work normally at 4V to 36V. When the power supply voltage is lower than 4V, the chip cannot work normally, and the chip output signal cannot be guaranteed to be low or high, causing the load to be in the on state or off state, and unable to maintain the off state. In this way, when the power supply voltage is undervoltage, the load state may be out of control. Utility Model Content

[0004] The present application provides a protection circuit, a battery management system and an electrical device, which can control the load to be in an off state when the power supply voltage is undervoltage, thereby improving the problem of load state loss of control during undervoltage.

[0005] In a first aspect, the present application provides a protection circuit, comprising a detection module and a control module: the detection module is connected to a power supply and a control module, the control module is connected to a power-consuming circuit, and the power-consuming circuit includes a power supply processor and a load; the detection module is used to detect the voltage of the power supply, and the control module is used to control the load to be in an off state when the voltage of the power supply is within a preset voltage range, the minimum voltage of the preset voltage range is less than the normal operating voltage of the power supply processor, and the maximum voltage of the preset voltage range is greater than or equal to the normal operating voltage of the power supply processor.

[0006] In an embodiment of the present application, a detection module and a control module are set up, the detection module is used to detect the voltage of the power supply to determine whether the power supply is under-voltage. When the power supply is under-voltage, the control module is used to control the load to be in an off state, so that when the power supply voltage is under-voltage, the load can be controlled to remain in an off state, thereby improving the problem of load state out of control during under-voltage.

[0007] In a possible implementation of the first aspect, the detection module includes a voltage division submodule and a first switch submodule;

[0008] The first end of the voltage divider submodule is connected to the power supply, the second end of the voltage divider submodule is grounded, the voltage dividing node of the voltage divider submodule is connected to the control end of the first switch submodule, the first switch submodule is connected to the power supply, the second end of the first switch submodule is grounded, and the second end of the first switch submodule is connected to the control module.

[0009] In an embodiment of the present application, the voltage dividing node of the voltage dividing submodule is connected to the control end of the first switch submodule, and the voltage of the control end of the first switch submodule changes with the change of the power supply voltage. The voltage of the control end of the first switch submodule can control the state of the first switch submodule, so as the voltage of the power supply changes, the first switch submodule can execute different states. When the first switch submodule is turned off, the voltage of the second end of the first switch submodule is equal to the ground voltage. When the first switch submodule is closed, the voltage of the second end of the first switch submodule is equal to the power supply voltage. The control module is connected to the second end of the first switch submodule, so in different states of the first switch submodule, the voltage connected to the control module is different, so that the detection module can control the control module to execute different states according to the different voltages of the power supply.

[0010] In a possible implementation manner of the first aspect, the control module includes a second switch submodule and a third switch submodule;

[0011] The control end of the second switch submodule is connected to the detection module, the first end of the second switch submodule is connected to the power supply, and the second end of the second switch submodule is grounded;

[0012] The control end of the third switch submodule is connected to the first end or the second end of the second switch submodule, the first end of the third switch submodule is grounded, and the second end of the third switch submodule is connected to the power circuit.

[0013] In the embodiment of the present application, as the voltage of the power supply changes, the voltage detected by the detection module changes, and the voltage of the control end of the second switch submodule also changes. Therefore, as the voltage of the power supply changes, the second switch submodule can execute different states. In addition, the control end of the third switch submodule is connected to the first end or the second end of the second switch submodule, and in different states of the second switch submodule, the voltage of the control end of the third switch submodule is different. Therefore, as the voltage of the power supply changes, the third switch submodule can also execute different states.

[0014] In a possible implementation manner of the first aspect, the detection module further includes a first current limiting submodule, and the second end of the first switch submodule is grounded through the first current limiting submodule.

[0015] When the first switch submodule is closed, the first current limiting submodule can be used to limit the current flowing through the first switch submodule, thereby protecting the first switch submodule.

[0016] In a possible implementation manner of the first aspect, the control module further includes a second current limiting submodule;

[0017] The control end of the third switch submodule is connected to the first end of the second switch submodule, and the first end of the second switch submodule is connected to the power supply through the second current limiting submodule;

[0018] Alternatively, the control end of the third switch submodule is connected to the second end of the second switch submodule, and the second end of the second switch submodule is grounded through the second current limiting submodule.

[0019] When the second switch submodule is closed, the second current limiting submodule can be used to limit the current flowing through the second switch submodule, thereby protecting the second switch submodule. In addition, the second current limiting submodule can also be used to limit the current flowing through the third switch submodule, thereby protecting the third switch submodule.

[0020] In a possible implementation manner of the first aspect, the voltage divider submodule includes a first resistor and a second resistor connected in series, and a connection node between the first resistor and the second resistor is a voltage divider node of the voltage divider submodule.

[0021] In the embodiment of the present application, the voltage division of the power supply can be achieved by setting two resistors connected in series, that is, the detection of the power supply voltage can be achieved, and the structure is relatively simple.

[0022] In a possible implementation manner of the first aspect, when the voltage of the power supply is within a preset voltage range, the first switch submodule and the second switch submodule are turned off, and the third switch submodule is turned on;

[0023] When the voltage of the power supply is less than the minimum voltage of the preset voltage range, the first switch submodule, the second switch submodule and the third switch submodule are turned off;

[0024] When the voltage of the power source is greater than the maximum voltage of the preset voltage range, the first switch submodule and the second switch submodule are closed, and the third switch submodule is turned off.

[0025] In this way, when the voltage of the power supply is within the preset voltage range, the protection circuit can input a control signal to the power circuit to control the load to be in the off state. When the voltage of the power supply is less than the minimum voltage of the preset voltage range, the power circuit cannot work, and the control module can be used to stop inputting the control signal to the power circuit. When the voltage of the power supply is greater than the maximum voltage of the preset voltage range, the power circuit works normally, and the control module can be used to control the stop of inputting the control signal to the power circuit.

[0026] In a possible implementation manner of the first aspect, the control module includes a second switch submodule and a third switch submodule;

[0027] The first switch submodule, the second switch submodule and the third switch submodule include field effect transistors or triodes.

[0028] In a possible implementation manner of the first aspect, the control module includes a second switch submodule and a third switch submodule;

[0029] The first switch submodule and the second switch submodule include field effect transistors or triodes, and the third switch submodule includes a photo-controlled transistor or a photocoupler switch.

[0030] In a second aspect, based on the same inventive concept, an embodiment of the present application further provides a battery management system, including:

[0031] Power circuits; and

[0032] A protection circuit as described in any embodiment of the first aspect.

[0033] In a possible implementation of the second aspect, the power circuit includes a load, a power processor, a controller, and a driver;

[0034] The power processor and the controller are connected to a first node, the controller and the driver are connected to a second node, and the driver and the load are connected to a third node;

[0035] The control module of the protection circuit is connected to any one of the first node, the second node, and the third node.

[0036] In a third aspect, based on the same inventive concept, an embodiment of the present application further provides an electrical device, comprising a battery management system as described in any embodiment of the second aspect.

[0037] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0039] Figure 1 This is a schematic diagram of the structure of a protection circuit according to an embodiment of the present application;

[0040] Figure 2 This is a structural schematic diagram of a protection circuit according to another embodiment of the present application;

[0041] Figure 3 This is a structural schematic diagram of a protection circuit according to another embodiment of the present application;

[0042] Figure 4 This is a structural schematic diagram of a protection circuit according to another embodiment of the present application;

[0043] Figure 5 This is a structural schematic diagram of a protection circuit according to another embodiment of the present application;

[0044] Figure 6 This is a structural schematic diagram of a protection circuit according to another embodiment of the present application;

[0045] Figure 7 This is a structural schematic diagram of a protection circuit according to another embodiment of the present application;

[0046] Figure 8 This is a structural schematic diagram of a protection circuit according to another embodiment of the present application;

[0047] Fig. 9 This is a structural schematic diagram of a protection circuit according to another embodiment of the present application;

[0048] Fig.10 A schematic diagram of the structure of a battery management system according to an embodiment of the present application.

[0049] Description of reference numerals:

[0050] 100. Protection circuit;

[0051] 11. Detection module; 111. Voltage dividing submodule; 112. First switch submodule; 113. First current limiting submodule;

[0052] 12. Control module; 121. Second switch submodule; 122. Third switch submodule; 123. Second current limiting submodule;

[0053] 200. Power circuit;

[0054] 211, power processor; 212, controller; 213, driver;

[0055] 22. Load;

[0056] 300, power supply;

[0057] 1000. Battery management system. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0059] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0060] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" 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 direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0061] The embodiments of the present application provide a protection circuit, a battery management system and an electric device. The protection circuit, the battery management system and the electric device provided in the embodiments of the present application will be described in detail below in conjunction with the accompanying drawings.

[0062] The protection circuit provided by the embodiment of the application is first introduced below.

[0063] like Figure 1 As shown, the protection circuit 100 includes a detection module 11 and a control module 12 .

[0064] The detection module 11 is connected to the power supply 300 and the control module 12 . The control module 12 is connected to the power circuit 200 . The power circuit 200 includes a power processor 211 and a load 22 .

[0065] The detection module 11 is used to detect the voltage of the power supply 300, and the control module 12 is used to control the load 22 to be in an off state when the voltage of the power supply 300 is within a preset voltage range. The minimum voltage of the preset voltage range is less than the normal working voltage of the power supply processor 211, and the maximum voltage of the preset voltage range is greater than or equal to the normal working voltage of the power supply processor 211.

[0066] Exemplarily, the maximum voltage of the preset voltage range may be slightly greater than the normal operating voltage of the power processor 211 .

[0067] The power circuit 200 is also connected to a power source 300 , and the power source 300 is used to supply power to the power circuit 200 .

[0068] It is understandable that when the voltage of the power supply 300 is within the preset voltage range, it can be understood that the power circuit 200 is in a state of undervoltage of the power supply voltage. The power circuit 200 can still work, but the working state is unstable.

[0069] Exemplarily, when the voltage of the power supply 300 is less than the minimum voltage of the preset voltage range, the power circuit 200 cannot work, the voltages of the first node A, the second node B, and the third node C of the power circuit 200 are all maintained at the default voltage, and the load 22 remains in the default off state.

[0070] When the voltage of the power source 300 is greater than the maximum voltage of the preset voltage range, the power supply voltage of the power-consuming circuit 200 is normal, and the power-consuming circuit 200 can operate normally.

[0071] The detection module 11 can control the control module 12 to execute different states according to different voltages of the power source 300 .

[0072] When the voltage of the power source 300 is within the preset voltage range, the control module 12 inputs a control signal to the power-consuming circuit 200 to control the load 22 to be in an off state.

[0073] When the voltage of the power source 300 is less than the minimum voltage of the preset voltage range, the power circuit 200 cannot work, and the control module 12 can be used to stop inputting control signals to the power circuit 200 .

[0074] When the voltage of the power source 300 is greater than the maximum voltage of the preset voltage range, the power-consuming circuit 202 operates normally, and the control module can be used to control the stop of inputting the control signal to the power-consuming circuit 202 .

[0075] As mentioned in the background art, in the case of an undervoltage of the power supply voltage, the state of the load may be out of control.

[0076] For example, Figure 1 As shown, the power processor 211 is used to drive the load 22, and the power supply 300 supplies power to the power processor 211. Exemplarily, the power circuit 20 may also include a controller 212 and a driver 213, and the power processor 211, the controller 212, and the driver 213 may be chips or circuits that perform related actions according to instructions.

[0077] In the absence of the protection circuit 100, when the voltage of the external power supply 300 drops below the normal operating voltage range of the power processor 211, the voltage output of the first node A will drop, and the controller 212 will not be able to maintain normal operation. Therefore, the potential of the second node B is uncontrollable, resulting in the potential of the third node C being uncontrollable as well, causing the voltage output by the driver 213 to possibly cause the load 22 to turn on or turn off, thereby causing the load 22 to be unable to remain in the off state, and the state of the load 22 may be out of control.

[0078] In the embodiment of the present application, a detection module 11 and a control module 12 are provided, the detection module 11 is used to detect the voltage of the power supply 300, so as to determine whether the power supply 300 is under-voltage powered. When the power supply 300 is under-voltage powered, the control module 12 is used to control the load 22 to be in an off state, so that when the power supply 300 voltage is under-voltage, the load 22 can be controlled to remain in an off state, thereby improving the problem of load state out of control during under-voltage.

[0079] The implementation details of the protection circuit of this embodiment are specifically described below. The following content is only provided for easy understanding of the implementation details and is not necessary for implementing this solution.

[0080] In some embodiments, Figure 2 As shown, the detection module 11 may include a voltage division submodule 111 and a first switch submodule 112 .

[0081] The first end of the voltage divider submodule 111 is connected to the power supply 300, the second end of the voltage divider submodule 111 is grounded GND, the voltage dividing node N1 of the voltage divider submodule 111 is connected to the control end of the first switch submodule 112, the first switch submodule 112 is connected to the power supply 300, the second end of the first switch submodule 112 is grounded GND, and the second end of the first switch submodule 112 is connected to the control module 12.

[0082] The voltage of the voltage dividing node N1 of the voltage dividing submodule 111 is the voltage divided between the power supply 300 and the ground GND. When the voltage of the power supply 300 changes, the voltage of the voltage dividing node N1 of the voltage dividing submodule 111 changes accordingly. It is understandable that the voltage of the voltage dividing node N1 of the voltage dividing submodule 111 is the voltage detected by the detection module 11.

[0083] The voltage dividing node N1 of the voltage dividing submodule 111 is connected to the control end of the first switch submodule 112, and the voltage of the control end of the first switch submodule 112 changes with the voltage of the power supply 300. The voltage of the control end of the first switch submodule 112 can control the state of the first switch submodule 112, so as the voltage of the power supply 300 changes, the first switch submodule 112 can execute different states.

[0084] For example, when the voltage of the power source 300 is within a preset voltage range, the first switch submodule 112 may be in an off state.

[0085] When the voltage of the power source 300 is less than the minimum voltage of the preset voltage range, the first switch submodule 112 may be in the off state.

[0086] When the voltage of the power source 300 is greater than the maximum voltage of the preset voltage range, the first switch submodule 112 may be in a closed state.

[0087] When the first switch submodule 112 is turned off, the voltage at the second end of the first switch submodule 112 is equal to the ground GND voltage. When the first switch submodule 112 is closed, the voltage at the second end of the first switch submodule 112 is equal to the voltage of the power supply 300. The control module 12 is connected to the second end of the first switch submodule 112, so in different states of the first switch submodule 112, the voltage connected to the control module 12 is different, so that the detection module 11 can control the control module 12 to execute different states according to different voltages of the power supply 300.

[0088] It should be noted that the structure of the detection module 11 in this application may include Figure 2 For example, in other examples, the detection module 11 may also be other structures, as long as the detection module 11 can detect the power supply voltage and instruct the control module 12 to perform different actions when the power supply voltage is different.

[0089] In some embodiments, Figure 3 or Figure 4 As shown, the control module 12 includes a second switch submodule 121 and a third switch submodule 122 .

[0090] The control end of the second switch submodule 121 is connected to the detection module 11 , the first end of the second switch submodule 121 is connected to the power source 300 , and the second end of the second switch submodule 121 is grounded GND.

[0091] Exemplarily, the control end of the second switch submodule 121 is connected to the second end of the first switch submodule 112 in the detection module 11 .

[0092] like Figure 3 As shown, the control end of the third switch submodule 122 is connected to the first end of the second switch submodule 121, or Figure 4 As shown, the control end of the third switch submodule 122 is connected to the second end of the second switch submodule 121 . In addition, the first end of the third switch submodule 122 is grounded GND, and the second end of the third switch submodule 122 is connected to the power circuit 200 .

[0093] As the voltage of the power source 300 changes, the voltage detected by the detection module 11 changes, and the voltage of the control end of the second switch submodule 121 also changes. Therefore, as the voltage of the power source 300 changes, the second switch submodule 121 can execute different states. In addition, the control end of the third switch submodule 122 is connected to the first end or the second end of the second switch submodule 121. In different states of the second switch submodule 121, the voltage of the control end of the third switch submodule 122 is different. Therefore, as the voltage of the power source 300 changes, the third switch submodule 122 can also execute different states.

[0094] As an example, Figure 3 As shown, the control end of the third switch submodule 122 is connected to the first end of the second switch submodule 121. When the voltage of the power supply 300 is within the preset voltage range, the second switch submodule 121 may be in an open state, and the third switch submodule 122 may be in a closed state. When the voltage of the power supply 300 is less than the minimum voltage of the preset voltage range, the second switch submodule 121 may be in an open state, and the third switch submodule 122 may be in an open state. When the voltage of the power supply 300 is greater than the maximum voltage of the preset voltage range, the second switch submodule 121 may be in a closed state, and the third switch submodule 122 may be in an open state.

[0095] As another example, Figure 4 As shown, the control end of the third switch submodule 122 is connected to the second end of the second switch submodule 121. When the voltage of the power supply 300 is within the preset voltage range, the second switch submodule 121 can be in a closed state, and the third switch submodule 122 can be in a closed state. When the voltage of the power supply 300 is less than the minimum voltage of the preset voltage range, the second switch submodule 121 can be in an open state, and the third switch submodule 122 can be in an open state. When the voltage of the power supply 300 is greater than the maximum voltage of the preset voltage range, the second switch submodule 121 can be in an open state, and the third switch submodule 122 can be in an open state.

[0096] For example, the second end of the third switch submodule 122 is connected to the second node B. When the third switch submodule 122 is closed, the second node B is connected to the ground GND, and the second node B is pulled down to a low level, thereby ensuring that the driver 213 cannot be enabled, that is, ensuring that the driver 213 is not enabled, so that the load 22 is in an off state. When the third switch submodule 122 is closed, the control module 12 cannot transmit a signal to the second node B, so that the level of the second node B is not affected by the control module 12.

[0097] It should be noted that the structure of the control module 12 in the present application may include: Figure 3 or Figure 4 For example, in other examples, the control module 12 may also be other structures, as long as the control module 12 can perform different actions under different power supply voltages.

[0098] In some embodiments, Figure 3 or Figure 4 As shown, the detection module 11 further includes a first current limiting submodule 113, and the second end of the first switch submodule 112 is grounded GND through the first current limiting submodule 113. When the first switch submodule 112 is closed, the first current limiting submodule 113 can be used to limit the current flowing through the first switch submodule 112, thereby protecting the first switch submodule 112.

[0099] Exemplarily, the control end of the second switch submodule 121 is connected to the second end of the first switch submodule 112 in the detection module 11, and the control end of the second switch submodule 121 can be grounded GND through the first current limiting submodule 113. It can be understood that the first current limiting submodule 113 can be used to limit the current flowing through the second switch submodule 121, thereby protecting the second switch submodule 121.

[0100] In some embodiments, Figure 3 or Figure 4 As shown, the control module 12 further includes a second current limiting submodule 123 .

[0101] As an example, Figure 3 As shown, the control end of the third switch submodule 122 is connected to the first end of the second switch submodule 121 , and the first end of the second switch submodule 121 is connected to the power supply through the second current limiting submodule 123 .

[0102] As another example, Figure 4 As shown, the control end of the third switch submodule 122 is connected to the second end of the second switch submodule 121 , and the second end of the second switch submodule 121 is grounded through the second current limiting submodule 123 .

[0103] When the second switch submodule 121 is closed, the second current limiting submodule 123 can be used to limit the current flowing through the second switch submodule 121, thereby protecting the second switch submodule 121. In addition, the second current limiting submodule 123 can also be used to limit the current flowing through the third switch submodule 122, thereby protecting the third switch submodule 122.

[0104] In some embodiments, Figure 5 or Figure 6 As shown, the voltage dividing submodule 111 includes a first resistor R1 and a second resistor R2 connected in series, and a connection node between the first resistor R1 and the second resistor R2 is a voltage dividing node N1 of the voltage dividing submodule 111 .

[0105] The first end of the first resistor R1 is the first end of the voltage divider module 111 , the second end of the first resistor R1 and the first end of the second resistor R2 are connected to the voltage divider node N1 , and the second end of the second resistor R2 is the second end of the voltage divider module 111 .

[0106] In the embodiment of the present application, the voltage division of the power supply can be achieved by setting two resistors connected in series, that is, the detection of the power supply voltage can be achieved, and the structure is relatively simple.

[0107] The resistance values ​​of the first resistor R1 and the second resistor R2 affect the voltage of the voltage-dividing node N1, thereby affecting the state of the first switch submodule 112. When the voltage of the power supply is within or outside the preset voltage range, the first switch submodule 112 can execute different states. That is, the resistance values ​​of the first resistor R1 and the second resistor R2 affect the size of the preset voltage range, and the ratio of the resistance values ​​of the first resistor R1 and the second resistor R2 can be adjusted to set the preset voltage range.

[0108] In some embodiments, when the voltage of the power supply 300 is within a preset voltage range, the first switch submodule 112 and the second switch submodule 121 are turned off, and the third switch submodule 122 is closed; when the voltage of the power supply 300 is less than the minimum voltage of the preset voltage range, the first switch submodule 112, the second switch submodule 121 and the third switch submodule 122 are turned off; when the voltage of the power supply 300 is greater than the maximum voltage of the preset voltage range, the first switch submodule 112 and the second switch submodule 121 are closed, and the third switch submodule 122 is turned off.

[0109] In this way, when the voltage of the power source 300 is within the preset voltage range, the protection circuit can input a control signal to the power circuit 200 to control the load 22 to be in the off state. When the voltage of the power source 300 is less than the minimum voltage of the preset voltage range, the power circuit 200 cannot work, and the control module 12 can be used to stop inputting the control signal to the power circuit 200. When the voltage of the power source 300 is greater than the maximum voltage of the preset voltage range, the power circuit 202 works normally, and the control module can be used to control the stop of inputting the control signal to the power circuit 200.

[0110] In some embodiments, Figure 5 or Figure 6 As shown, the first switch submodule 112, the second switch submodule 121 and the third switch submodule 122 include field effect transistors. It should be noted that, although not shown in the drawings of the present application, in other examples, the first switch submodule 112, the second switch submodule 121 and the third switch submodule 122 may include triodes.

[0111] For example, Figure 5or Figure 6 As shown, the first switch submodule 112 includes a first switch tube S1, and the first switch tube S1 includes a PMOS transistor. The gate of the first switch tube S1 serves as the control end of the first switch submodule 112, the source of the first switch tube S1 serves as the first end of the first switch submodule 112, and the drain of the first switch tube S1 serves as the second end of the first switch submodule 112.

[0112] The condition for the PMOS transistor to be closed is Vgs_P≤Vth_P, where Vgs_P is the voltage difference between the gate and the source of the PMOS transistor, and Vth_P is the threshold voltage of the transistor. The threshold voltage of the PMOS transistor is less than 0.

[0113] For example, Figure 5 or Figure 6 As shown, the second switch submodule 121 includes a second switch tube S2, and the third switch submodule 122 includes a third switch tube S3. The third switch tube S3 includes an NMOS transistor. The gate of the third switch tube S3 serves as the control end of the third switch submodule 122, the source of the third switch tube S3 serves as the first end of the third switch submodule 122, and the drain of the third switch tube S3 serves as the second end of the third switch submodule 122.

[0114] The condition for the NMOS transistor to be closed is Vgs_N≥Vth_N, where Vgs_N is the voltage difference between the gate and the source of the transistor, and Vth_N is the threshold voltage of the transistor. The threshold voltage of the NMOS transistor is greater than 0.

[0115] As an example, Figure 5 As shown, the control end of the third switch submodule 122 is connected to the first end of the second switch submodule 121, and the second switch tube S2 includes an NMOS transistor. The gate of the second switch tube S2 serves as the control end of the second switch submodule 121, the source of the second switch tube S2 serves as the second end of the second switch submodule 121, and the drain of the second switch tube S2 serves as the first end of the second switch submodule 121.

[0116] As an example, Figure 6 As shown, the control end of the third switch submodule 122 is connected to the second end of the second switch submodule 121, and the second switch tube S2 includes a PMOS transistor. The gate of the second switch tube S2 serves as the control end of the second switch submodule 121, the source of the second switch tube S2 serves as the first end of the second switch submodule 121, and the drain of the second switch tube S2 serves as the second end of the second switch submodule 121.

[0117] In some embodiments, Figure 5 or Figure 6As shown, the first current limiting submodule 113 includes a third resistor R3, and the second current limiting submodule 123 includes a fourth resistor R4.

[0118] The power supply 300 may include a power-on process and a power-off process. The voltage of the power supply 300 is recorded as Vin, the threshold voltage of the first switch tube S1 is recorded as Vth_S1, the threshold voltage of the third switch tube S3 is recorded as Vth_S3, Vth_S1<0, Vth_S3>0.

[0119] Below we first Figure 5 As an example, the working principle of the protection circuit 100 is explained.

[0120] The power-on process of the power supply 300 includes the following scenarios:

[0121] Scenario 1: When Vin is less than Vth_S3, the first switch tube S1, the second switch tube S2 and the third switch tube S3 can all remain disconnected, and the second node B maintains the voltage in the default state. In this case, Vin is relatively small, and the power circuit 200 cannot work, so the load 22 can be guaranteed to be in the off state. Exemplarily, the second node B is at a high level in the default state.

[0122] It should be noted that the absolute value of the threshold voltage of the first switch tube S1 and the threshold voltage of the third switch tube S3 may be in the same horizontal range, that is, the absolute value of Vth_S1 and Vth_S3 may be substantially the same, so when Vin<Vth_S3,

[0123] Scene 2, When the first switch tube S1 and the second switch tube S2 remain turned off, the third switch tube S3 is closed, and the second node B is pulled down to a low level, which can ensure that the driver 213 is not enabled, thereby controlling the load 22 to remain in the off state.

[0124] Scene three, When the first switch tube S1 and the second switch tube S2 are closed, the third switch tube S3 is open, and the level of the second node B is not affected by the control module 12. In this case, Vin is within the policy operating voltage range of the power circuit 200, and the power circuit 200 can work normally.

[0125] The power-off process of the power supply 300 includes the following scenarios:

[0126] Scene 4, When the first switch tube S1 and the second switch tube S2 are closed, the third switch tube S3 is open, and the level of the second node B is not affected by the control module 12. In this case, Vin is within the policy operating voltage range of the power circuit 200, and the power circuit 200 can work normally.

[0127] Scene Five, When the first switch tube S1 and the second switch tube S2 remain turned off, the third switch tube S3 is closed, and the second node B is pulled down to a low level, which can ensure that the driver 213 is not enabled, thereby controlling the load 22 to remain in the off state.

[0128] Scenario 6: When Vin is less than Vth_S3, the first switch tube S1, the second switch tube S2 and the third switch tube S3 can all remain disconnected, and the second node B maintains the voltage in the default state. In this case, Vin is relatively small, and the power circuit 200 cannot work, so the load 22 can be guaranteed to be in the off state. Exemplarily, the second node B is at a high level in the default state.

[0129] Then Figure 6 As an example, the working principle of the protection circuit 100 is explained.

[0130] The power-on process of the power supply 300 includes the following scenarios:

[0131] Scenario 7: When Vin is less than Vth_S3, the first switch tube S1, the second switch tube S2 and the third switch tube S3 can all remain disconnected, and the second node B maintains the voltage in the default state. In this case, Vin is relatively small, and the power circuit 200 cannot work, so the load 22 can be guaranteed to be in the off state. Exemplarily, the second node B is at a high level in the default state.

[0132] Scene 8, When the first switch tube S1 is turned off, the second switch tube S2 is turned on, the third switch tube S3 is turned on, and the second node B is pulled down to a low level, which can ensure that the driver 213 is not enabled, thereby controlling the load 22 to remain in the off state.

[0133] Scene Nine, When the first switch tube S1 is closed, the second switch tube S2 is opened, the third switch tube S3 is opened, and the level of the second node B is not affected by the control module 12. In this case, Vin is within the policy operating voltage range of the power circuit 200, and the power circuit 200 can work normally.

[0134] The power-off process of the power supply 300 includes the following scenarios:

[0135] Scene 10, When the first switch tube S1 is closed, the second switch tube S2 is opened, the third switch tube S3 is opened, and the level of the second node B is not affected by the control module 12. In this case, Vin is within the policy operating voltage range of the power circuit 200, and the power circuit 200 can work normally.

[0136] Scene 11, When the first switch tube S1 is turned off, the second switch tube S2 is turned on, the third switch tube S3 is turned on, and the second node B is pulled down to a low level, which can ensure that the driver 213 is not enabled, thereby controlling the load 22 to remain in the off state.

[0137] Scenario 12: When Vin is less than Vth_S3, the first switch tube S1, the second switch tube S2 and the third switch tube S3 can all remain disconnected, and the second node B maintains the voltage in the default state. In this case, Vin is relatively small, and the power circuit 200 cannot work, so the load 22 can be guaranteed to be in the off state. Exemplarily, the second node B is at a high level in the default state.

[0138] It is understandable that the input voltage Vin of the external power supply 300 is During the interval, the driver 213 can be ensured not to be enabled, thereby controlling the load 22 to remain in the off state. The preset voltage range can be The specific upper and lower limits of the preset voltage range can be adjusted by selecting the first switch tube S1 and the third switch tube S3 and the resistance ratio of the first resistor R1 and the second resistor R2.

[0139] In other embodiments, Figure 7 or Figure 8 As shown, the first switch submodule 112 and the second switch submodule 121 include field effect transistors, and the third switch submodule 122 may include a photo-controlled transistor or a photo-coupler switch. It should be noted that, although not shown in the drawings of the present application, in other examples, the first switch submodule 112 and the second switch submodule 121 may include a triode, and the third switch submodule 122 may include a photo-controlled transistor or a photo-coupler switch.

[0140] Below we first Figure 7 or Figure 8 As an example, the working principle of the protection circuit 100 is explained.

[0141] The power-on process of the power supply 300 includes the following scenarios:

[0142] Scenario 13, when Vin<IFoff×R4+VF, the first switch tube S1, the second switch tube S2 and the third switch tube S3 can all remain disconnected, and the second node B maintains the voltage in the default state. In this case, Vin is relatively small, and the power circuit 200 cannot work, so the load 22 can be guaranteed to be in the off state. Exemplarily, the second node B is at a high level in the default state. IFoff is the off current of the photo-controlled transistor or the photo-coupler switch, and VF is the voltage drop of the light-emitting diode in the photo-controlled transistor or the photo-coupler switch.

[0143] Scene 14, When the first switch tube S1 and the second switch tube S2 remain turned off, the third switch tube S3 is closed, and the second node B is pulled down to a low level, which can ensure that the driver 213 is not enabled, thereby controlling the load 22 to remain in the off state.

[0144] Scene 15, When the first switch tube S1 and the second switch tube S2 are closed, the third switch tube S3 is open, and the level of the second node B is not affected by the control module 12. In this case, Vin is within the policy operating voltage range of the power circuit 200, and the power circuit 200 can work normally.

[0145] The power-off process of the power supply 300 includes the following scenarios:

[0146] Scene 16, When the first switch tube S1 and the second switch tube S2 are closed, the third switch tube S3 is open, and the level of the second node B is not affected by the control module 12. In this case, Vin is within the policy operating voltage range of the power circuit 200, and the power circuit 200 can work normally.

[0147] Scene 17, When the first switch tube S1 and the second switch tube S2 remain turned off, the third switch tube S3 is closed, and the second node B is pulled down to a low level, which can ensure that the driver 213 is not enabled, thereby controlling the load 22 to remain in the off state.

[0148] Scenario 18, when Vin<Vth_S3, the first switch tube S1, the second switch tube S2 and the third switch tube S3 can all remain disconnected, and the second node B maintains the voltage in the default state. In this case, Vin is relatively small, and the power circuit 200 cannot work, so the load 22 can be guaranteed to be in the off state. Exemplarily, the second node B is at a high level in the default state.

[0149] For example, Figures 5 to 9 As shown, the power circuit 200 includes a power processor 211, a controller 212 and a driver 213. The power processor 211 and the controller 212 are connected to a first node A, the controller 212 and the driver 213 are connected to a second node B, and the driver 213 and the load 22 are connected to a third node C.

[0150] The control module 12 of the protection circuit 100 can be connected to any one of the first node A, the second node B, and the third node C. That is to say, the protection circuit 100 can be used to control the potential of any one of the first node A, the second node B, and the third node C, and can ensure that the direct drive signal controlling the load maintains a low level under undervoltage conditions to avoid malfunction of the load.

[0151] It should be noted that Figures 5 to 8The control module 12 is connected to the second node B. Fig. 9 The control module 12 is connected to the third node C for illustration, which is not intended to limit the present application.

[0152] It should be noted that the switch types included in each switch module in the embodiment of the present application are only examples and are not intended to limit the present application. Other structures that can achieve the same function are also within the protection scope of the present application.

[0153] In addition, in the embodiments of the present application, the voltage divider module includes resistors connected in series, and the current limiting module includes resistors. Other devices that can be used for voltage division or current limiting are also within the protection scope of the present application.

[0154] Based on the same inventive concept, the present application also provides a battery management system. Fig.10 As shown, the battery management system 1000 includes a power circuit 200 and a protection circuit 100, and the protection circuit 100 includes the protection circuit in any of the above embodiments. It can be understood that the battery management system has the beneficial effects of the protection circuit provided in the embodiments of the present application, and the specific description of the protection circuit in the above embodiments can be referred to, and this embodiment will not be repeated here.

[0155] In some embodiments, Figures 5 to 9 As shown, the power circuit 200 includes a power processor 211, a controller 212 and a driver 213. The power processor 211 and the controller 212 are connected to a first node A, the controller 212 and the driver 213 are connected to a second node B, and the driver 213 and the load 22 are connected to a third node C.

[0156] The control module 12 of the protection circuit 100 can be connected to any one of the first node A, the second node B, and the third node C. That is to say, the protection circuit 100 can be used to control the potential of any one of the first node A, the second node B, and the third node C, and can ensure that the direct drive signal controlling the load maintains a low level under undervoltage conditions to avoid malfunction of the load.

[0157] Exemplarily, the power supply 300 may be a low voltage power supply of 12V or 24V.

[0158] The power processor 211 converts the voltage received from the power source 300 and then supplies power to the controller 212 and the driver 213. For example, the power processor 211 may be a DC / DC converter.

[0159] The controller 212 may be a main control chip of the BMS, and is used to output a driving signal to control the driver 213 .

[0160] Exemplarily, the controller 212 may be a chip or circuit that performs related actions according to instructions. For example, the controller 212 may be a microcontroller unit (MCU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. For another example, the controller 212 may include an external clock, a random access memory (RAM), a read-only memory (ROM), etc. The present application does not limit the specific structure of the controller 212.

[0161] The driver 213 can be used as a power switch to control the path of the external power output to the load 22 .

[0162] The load 22 may be a general term for driving loads, for example, the load may be a relay, a lamp, a sensor, etc.

[0163] Based on the same inventive concept, the present application also provides an electric device. The electric device includes a battery management system, and the battery management system includes the protection circuit in any of the above embodiments. It can be understood that the electric device has the beneficial effects of the protection circuit provided in the embodiments of the present application, and the specific description of the protection circuit in the above embodiments can be referred to, and this embodiment will not be repeated here.

[0164] It should be noted that in the embodiments shown in the above figures, the resistor is represented by a single resistor, and the capacitor is represented by a single capacitor. In other embodiments, the resistor may be an integration of series, parallel or mixed resistors, and the capacitor may be an integration of series, parallel or mixed capacitors. The specific parameters of each device can be set according to actual needs, and this application does not limit this.

[0165] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0166] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present application, and should be understood that the protection scope of the present application is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present application based on the technical revelations disclosed in the present application, and these variations and combinations are still within the protection scope of the present application.

[0167] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A protection circuit, characterized in that: Including detection module and control module: The detection module is connected to the power supply and the control module, the control module is connected to the power circuit, and the power circuit includes a power processor and a load; The detection module is used to detect the voltage of the power supply, and the control module is used to control the load to be in an off state when the voltage of the power supply is within a preset voltage range, the minimum voltage of the preset voltage range is less than the normal working voltage of the power processor, and the maximum voltage of the preset voltage range is greater than or equal to the normal working voltage of the power processor.

2. The protection circuit according to claim 1, characterized in that: The detection module includes a voltage division submodule and a first switch submodule; The first end of the voltage divider submodule is connected to the power supply, the second end of the voltage divider submodule is grounded, the voltage dividing node of the voltage divider submodule is connected to the control end of the first switch submodule, the first switch submodule is connected to the power supply, the second end of the first switch submodule is grounded, and the second end of the first switch submodule is connected to the control module.

3. The protection circuit according to claim 2, characterized in that: The control module includes a second switch submodule and a third switch submodule; The control end of the second switch submodule is connected to the detection module, the first end of the second switch submodule is connected to the power supply, and the second end of the second switch submodule is grounded; The control end of the third switch submodule is connected to the first end or the second end of the second switch submodule, the first end of the third switch submodule is grounded, and the second end of the third switch submodule is connected to the power circuit.

4. The protection circuit according to claim 2, characterized in that: The detection module further includes a first current limiting submodule, and the second end of the first switch submodule is grounded through the first current limiting submodule.

5. The protection circuit according to claim 3, characterized in that: The control module also includes a second current limiting submodule; The control end of the third switch submodule is connected to the first end of the second switch submodule, and the first end of the second switch submodule is connected to the power supply through the second current limiting submodule; Alternatively, the control end of the third switch submodule is connected to the second end of the second switch submodule, and the second end of the second switch submodule is grounded through the second current limiting submodule.

6. The protection circuit according to claim 2, characterized in that: The voltage dividing submodule includes a first resistor and a second resistor connected in series, and a connection node between the first resistor and the second resistor is a voltage dividing node of the voltage dividing submodule.

7. The protection circuit according to claim 3, characterized in that: When the voltage of the power supply is within the preset voltage range, the first switch submodule and the second switch submodule are turned off, and the third switch submodule is closed; When the voltage of the power supply is less than the minimum voltage of the preset voltage range, the first switch submodule, the second switch submodule and the third switch submodule are turned off; When the voltage of the power source is greater than the maximum voltage of the preset voltage range, the first switch submodule and the second switch submodule are closed, and the third switch submodule is turned off.

8. The protection circuit according to claim 2, characterized in that: The control module includes a second switch submodule and a third switch submodule; The first switch submodule, the second switch submodule and the third switch submodule include field effect transistors or triodes.

9. The protection circuit according to claim 2, characterized in that: The control module includes a second switch submodule and a third switch submodule; The first switch submodule and the second switch submodule include field effect transistors or triodes, and the third switch submodule includes a photo-controlled transistor or a photocoupler switch.

10. A battery management system, characterized in that: include: Power circuits; as well as, A protection circuit as claimed in any one of claims 1 to 9.

11. The battery management system according to claim 10, characterized in that: The power circuit includes a load, a power processor, a controller, and a driver; The power processor and the controller are connected to a first node, the controller and the driver are connected to a second node, and the driver and the load are connected to a third node; The control module of the protection circuit is connected to any one of the first node, the second node, and the third node.

12. An electrical device, characterized in that: Comprising a battery management system as claimed in claim 10 or 11.

Images