Charging protection circuit, control method thereof and electronic equipment

Abstract

The invention relates to a charging protection circuit and a control method thereof, and electronic equipment, and the charging protection circuit is characterized in that an AC / DC power converter is used for providing an output electric signal for charging for a load; the on-off control circuit is connected with the AC / DC power converter and is used for disconnecting a loop for charging the load by the AC / DC power converter according to the disconnection control signal; the adjusting loop is connected with the AC / DC power converter and used for responding to the adjusting control signal and generating an adjusting electric signal used for adjusting amplitude reduction of the output electric signal according to the output electric signal. The controller is connected with the on-off control circuit and the adjusting loop and is used for generating an adjusting control signal before the off control signal is generated; and the output electric signal is continuously adjusted for the preset time according to the adjusting electric signal, so that after the amplitude of the output electric signal is reduced, the disconnection control signal is generated, surge peak voltage and charging stress can be obviously reduced or avoided, and the working performance and reliability of the AC / DC power converter are improved.

Description

Technical Field

[0001] The present invention relates to the field of power electronics technology, and particularly to a charging protection circuit, a control method thereof, and an electronic device. Background Art

[0002] As an important tool for modern urban travel, the battery life of electric vehicles has always been the focus of user attention. The correct charging method can not only extend the service life of the battery, but also ensure the stable performance of the electric vehicle.

[0003] However, in the traditional technology, when it is necessary to turn off the output in the normal charging state of the electric vehicle charger, the method of directly turning off the output switching device is usually adopted to stop charging, which is likely to cause a surge peak voltage inside the charger, bring greater stress to the internal circuit of the charger, and even cause the charger to stop due to overvoltage protection or device damage, seriously reducing the performance and reliability of the charger operation. Summary of the Invention

[0004] Based on this, in view of the problems in the above background art, it is necessary to provide a charging protection circuit, a control method thereof, and an electronic device, which can significantly reduce or avoid the generation of surge peak voltage and charging stress by continuously adjusting the amplitude of the output electrical signal of the charger and then disconnecting the charging loop of the charger to the load, and improve the performance and reliability of the charger operation.

[0005] The first aspect of the present application provides a charging protection circuit, including an AC / DC power converter, a switching control circuit, an adjustment loop, and a controller. The AC / DC power converter is used to provide an output electrical signal for charging to a load, and the output electrical signal includes a voltage signal and / or a current signal. The switching control circuit is connected to the AC / DC power converter and is used to disconnect the charging loop of the AC / DC power converter to the load according to a disconnection control signal. The adjustment loop is connected to the AC / DC power converter and is used to respond to an adjustment control signal and generate an adjustment electrical signal for adjusting the amplitude reduction of the output electrical signal according to the output electrical signal. The controller is connected to both the switching control circuit and the adjustment loop and is configured to: generate an adjustment control signal before generating a disconnection control signal; continuously adjust the output electrical signal for a preset time according to the adjustment electrical signal so that the amplitude of the output electrical signal is reduced, and then generate a disconnection control signal for controlling the operation of the switching control circuit.

[0006] In the charging protection circuit in the above embodiments, before the controller generates a disconnection control signal for controlling the on-off control circuit to disconnect the loop for the AC / DC power converter to charge the load, an adjustment control signal is generated; according to the adjustment electrical signal, the output electrical signal of the AC / DC power converter is continuously adjusted for a preset time, so that after the amplitude of the output electrical signal of the AC / DC power converter decreases, a disconnection control signal for controlling the on-off control circuit to act is generated, and according to this disconnection control signal, the loop for the AC / DC power converter to charge the load is disconnected, significantly reducing or avoiding the generation of surge peak voltage and charging stress, avoiding the occurrence of charger overvoltage protection shutdown or device damage events, and improving the performance and reliability of the charger operation.

[0007] In some embodiments, the adjustment control signal includes at least one of a current control signal, a positive feedback reference voltage, or a negative feedback reference voltage; before generating the disconnection control signal, the controller generates a gradually decreasing positive feedback reference voltage or a gradually increasing negative feedback reference voltage. By the controller generating a gradually decreasing positive feedback reference voltage or a gradually increasing negative feedback reference voltage, the voltage loop continuously adjusts the output electrical signal for a preset time according to the gradually decreasing positive feedback reference voltage or the gradually increasing negative feedback reference voltage, so that after the amplitude of the output electrical signal of the AC / DC power converter decreases, the controller is triggered to generate a disconnection control signal, and thus according to this disconnection control signal, the loop for the AC / DC power converter to charge the load is disconnected, significantly reducing or avoiding the generation of surge peak voltage and charging stress.

[0008] In some embodiments, the adjustment loop includes a voltage loop, and the voltage loop is connected to both the AC / DC power converter and the controller and is configured to: after continuously adjusting the output electrical signal for a preset time according to the gradually decreasing positive feedback reference voltage or the gradually increasing negative feedback reference voltage, trigger the controller to generate a disconnection control signal.

[0009] In some embodiments, the adjustment loop includes a current loop, and the current loop is connected to both the AC / DC power converter and the controller and is configured to: after continuously adjusting the current signal for a preset time according to the current control signal, generate a disconnection control signal, and then trigger the controller to generate a disconnection control signal

[0010] In some embodiments, the charging protection circuit further includes an output voltage detection circuit and / or an output current detection circuit; the output voltage detection circuit is connected to both the AC / DC power converter and the controller. When the output voltage detection circuit detects that the amplitude of the voltage signal decreases, a first indication signal is generated to indicate the controller to generate a disconnection control signal; the output current detection circuit is connected to both the AC / DC power converter and the controller. When the output current detection circuit detects that the amplitude of the current signal decreases, a second indication signal is generated to indicate the controller to generate a disconnection control signal. After the output voltage detection circuit detects that the amplitude of the voltage signal output by the AC / DC power converter decreases, a first indication signal is generated to indicate the controller to generate a disconnection control signal; or after the output current detection circuit detects that the amplitude of the current signal output by the AC / DC power converter decreases, a second indication signal is generated to indicate the controller to generate a disconnection control signal, significantly reducing or avoiding the generation of surge peak voltage and charging stress.

[0011] In some embodiments, when the output voltage detection circuit detects that the amplitude of the voltage signal decreases and the amplitude is within a preset range, a first indication signal is generated to indicate the controller to generate a disconnection control signal, so as to significantly reduce or avoid the generation of surge peak voltage and charging stress.

[0012] In some embodiments, when the output current detection circuit detects that the amplitude of the current signal decreases and is less than a preset threshold, a second indication signal is generated to indicate the controller to generate a disconnection control signal, so as to significantly reduce or avoid the generation of surge peak voltage and charging stress.

[0013] In some embodiments, the charging protection circuit further includes a voltage loop detection circuit. The voltage loop detection circuit is connected to both the voltage loop and the controller. After the controller generates a positive feedback reference voltage or a negative feedback reference voltage, when the voltage loop detection circuit detects that the voltage loop is normally activated, a third indication signal is generated to indicate the controller to generate a disconnection control signal. Thus, after the normally activated voltage loop continuously adjusts the output electrical signal for a preset time, when the amplitude of the output electrical signal of the AC / DC power converter decreases, the controller is triggered to generate a disconnection control signal, so as to reduce the surge peak voltage and charging stress.

[0014] In some embodiments, the preset time is a fixed time determined according to historical data of the output electrical signal and / or the adjustment electrical signal; before generating the adjustment electrical signal, the controller obtains the fixed time, so that after the adjustment loop continuously adjusts the output electrical signal of the AC / DC power converter for the fixed time, the amplitude of the voltage signal output by the AC / DC power converter is reduced and the amplitude is within a preset range, or the amplitude of the current signal output by the AC / DC power converter is reduced and is less than a preset threshold, thereby significantly reducing or avoiding the generation of surge peak voltage and charging stress, and improving the performance and reliability of the charger operation.

[0015] In some embodiments, the amplitude of the positive feedback reference voltage or the negative feedback reference voltage is related to the target amplitude of the voltage signal; the target amplitude is greater than the minimum operating voltage amplitude for the normal uninterrupted operation of the AC / DC power converter, which is convenient for the adjustment loop to linearly decrease the amplitude of the output electrical signal of the AC / DC power converter and avoid the generation of surge peak voltage and charging stress.

[0016] In some embodiments, the controller includes a digital-to-analog converter, and the digital-to-analog converter is connected to the adjustment loop and is used to generate a positive feedback reference voltage or a negative feedback reference voltage;

[0017] In some embodiments, the controller includes a pulse width modulator, and the pulse width modulator is connected to the adjustment loop and is used to generate a positive feedback reference voltage or a negative feedback reference voltage, so that the adjustment loop adjusts the amplitude of the output electrical signal of the AC / DC power converter to decrease based on the positive feedback reference voltage or the negative feedback reference voltage, and avoid the generation of surge peak voltage and charging stress.

[0018] In some embodiments, the charging protection circuit further includes a filtering circuit, and the filtering circuit is connected to both the digital-to-analog converter and the voltage loop, or is connected to both the pulse width modulator and the voltage loop, and is used to provide a filtered positive feedback reference voltage or a filtered negative feedback reference voltage to the voltage loop, to avoid adverse effects of noise or interference waves on the adjustment loop, resulting in the AC / DC power converter generating an output electrical signal with an increasing amplitude after continuous adjustment by the regulated loop, thereby avoiding events such as charger overvoltage protection shutdown or device damage.

[0019] In some embodiments, after generating the disconnection control signal and before the AC / DC power converter charges the load again, the controller generates a positive feedback reference voltage with an amplitude less than a first threshold or a negative feedback reference voltage with an amplitude greater than a second threshold; the first threshold is less than the second threshold, to avoid high energy consumption of the adjustment loop during the period when the AC / DC power converter does not charge the load.

[0020] In some embodiments, the positive feedback reference voltage is positively correlated with the amplitude of the regulation electrical signal, so that the regulation loop adjusts the amplitude of the output electrical signal of the AC / DC power converter to linearly or gradually decrease according to the positive feedback reference voltage.

[0021] In some embodiments, the negative feedback reference voltage is negatively correlated with the amplitude of the regulation electrical signal, so that the regulation loop adjusts the amplitude of the output electrical signal of the AC / DC power converter to linearly or gradually decrease according to the negative feedback reference voltage.

[0022] In some embodiments, the on-off control circuit includes an output switching device, a control switching device, and a voltage conversion circuit. The first end of the output switching device is connected to the DC power supply and is used as the positive output terminal of the charger. The second end is connected to the output end of the current loop and is used as the negative output terminal of the charger. The third end is connected to the output end of the voltage loop. The first end of the control switching device is connected to both the second end and the control end of the output switching device. The second end is connected to the third DC power supply. The first end of the voltage conversion circuit is connected to the control end of the control switching device, the second end is grounded, and the control end is used to receive the disconnection control signal. The voltage conversion circuit converts the amplitude of the disconnection control signal to the appropriate operating voltage amplitude range required by the control switching device, so as to turn on the control switching device according to the disconnection control signal, thereby controlling the output switching device to disconnect the charging circuit of the AC / DC power converter to the load.

[0023] In some embodiments, the output switching device includes a first switching transistor and a second switching transistor. The first end of the first switching transistor is connected to the first DC power supply. The first end of the second switching transistor is connected to the second end of the first switching transistor. The second end is connected to the second DC power supply and is used as the positive output terminal of the charger. The control end is connected to the first end of the control switching device and is connected to the control end of the first switching transistor. The first switching transistor and the second switching transistor are used to isolate the first DC power supply and the second DC power supply, avoiding the adverse effects of the electrical signals on the load side on the second DC power supply, and also avoiding the adverse effects of the first DC power supply on the load side. Moreover, the first switching transistor and the second switching transistor cooperate with each other and work together, which can also improve the working stability and reliability of the charging protection circuit.

[0024] In some embodiments, the control switching device includes a third switching transistor. The first end of the third switching transistor is connected to the control end of the second switching transistor and is connected to the first end of the second switching transistor via a first voltage-dividing resistor. The second end is connected to the third DC power supply via a first current-limiting resistor. The control end is connected to the first end of the voltage conversion circuit via a second current-limiting resistor. The third switching transistor is used to transmit the disconnection control signal to the first switching transistor and the second switching transistor, so as to control the disconnection of the charging circuit of the AC / DC power converter to the load according to the disconnection control signal.

[0025] In some embodiments, the voltage conversion circuit includes a fourth switching transistor. The first end of the fourth switching transistor is connected to the control end of the third switching transistor via a second current-limiting resistor, the second end is grounded, and the control end is connected to a disconnection control signal via a third current-limiting resistor. The third current-limiting resistor is used to protect the fourth switching transistor from being adversely affected by the disconnection control signal; the fourth switching transistor can convert the amplitude of the disconnection control signal to an appropriate operating voltage amplitude range required for controlling the switching device.

[0026] In some embodiments, the voltage loop includes a first operational amplifier. The inverting input terminal of the first operational amplifier is sequentially connected to a first DC power supply via a fourth current-limiting resistor and a fifth current-limiting resistor, and the non-inverting input terminal is connected to a positive feedback reference voltage or a negative feedback reference voltage via a sixth current-limiting resistor; wherein, the connection node of the fourth current-limiting resistor and the fifth current-limiting resistor is used as the output terminal of the voltage loop. The non-inverting input terminal of the first operational amplifier receives the positive feedback reference voltage or the negative feedback reference voltage, the inverting input terminal of the first operational amplifier is sequentially connected to the first DC power supply via the fourth current-limiting resistor and the fifth current-limiting resistor, and the connection node of the fourth current-limiting resistor and the fifth current-limiting resistor is used as the output terminal of the voltage loop, so as to continuously adjust the output electrical signal to reduce the amplitude of the output electrical signal.

[0027] In some embodiments, the current loop includes a second operational amplifier. The inverting input terminal of the second operational amplifier is sequentially connected to a current signal via a seventh current-limiting resistor and an eighth current-limiting resistor, and the non-inverting input terminal is connected to a current control signal via a ninth current-limiting resistor; wherein, the connection node of the seventh current-limiting resistor and the eighth current-limiting resistor is connected to the controller, so that after the non-inverting input terminal of the second operational amplifier receives the adjustment control signal provided by the controller, a current adjustment signal for continuously adjusting the output electrical signal of the AC / DC power converter is output via the inverting input terminal and the seventh current-limiting resistor.

[0028] According to some embodiments, a second aspect of the present application provides a method for controlling a charging protection circuit, including:

[0029] Before generating the disconnection control signal, generate an adjustment control signal;

[0030] According to the adjustment control signal, control the adjustment loop to generate an adjustment electrical signal, and the adjustment electrical signal is used to adjust the amplitude of the output electrical signal for charging provided by the AC / DC power converter to the load to decrease;

[0031] According to the adjustment electrical signal, continuously adjust the output electrical signal for a preset time, so that after the amplitude of the output electrical signal decreases, generate a disconnection control signal;

[0032] According to the disconnection control signal, control the on-off control circuit to disconnect the loop for the AC / DC power converter to charge the load.

[0033] In the charging protection circuit control method in the above embodiments, before generating a disconnection control signal for controlling the disconnection of the loop for the AC / DC power converter to charge the load by the on-off control circuit, an adjustment control signal is generated; the output electrical signal of the AC / DC power converter is continuously adjusted according to the adjustment electrical signal for a preset time, so that after the amplitude of the output electrical signal of the AC / DC power converter decreases, a disconnection control signal is generated, and according to the disconnection control signal, the loop for the AC / DC power converter to charge the load is disconnected, significantly reducing or avoiding the generation of surge spike voltage and charging stress, avoiding the occurrence of charger overvoltage protection shutdown or device damage events, and improving the performance and reliability of the charger operation.

[0034] In some embodiments, the adjustment control signal includes at least one of a current control signal, a positive feedback reference voltage, or a negative feedback reference voltage; before generating the disconnection control signal, a gradually decreasing positive feedback reference voltage or a gradually increasing negative feedback reference voltage is generated; according to the gradually decreasing positive feedback reference voltage or the gradually increasing negative feedback reference voltage, after the adjustment loop is controlled to continuously adjust the output electrical signal for a preset time, a disconnection control signal is generated. By controlling the adjustment loop to continuously adjust the output electrical signal for a preset time according to the gradually decreasing positive feedback reference voltage or the gradually increasing negative feedback reference voltage, the output electrical signal of the AC / DC power converter is gradually reduced to a preset value, and then a disconnection control signal is generated, so that according to the disconnection control signal, the loop for the AC / DC power converter to charge the load is disconnected, significantly reducing or avoiding the generation of surge spike voltage and charging stress.

[0035] In some embodiments, after the adjustment loop is controlled to continuously adjust the current signal for a preset time according to the current control signal, so that the amplitude of the output electrical signal of the AC / DC power converter decreases, a disconnection control signal is generated, and according to the disconnection control signal, the loop for the AC / DC power converter to charge the load is disconnected, significantly reducing or avoiding the generation of surge spike voltage and charging stress.

[0036] According to some embodiments, a third aspect of the present application provides an electronic device, including: the charging protection circuit described in any of the foregoing embodiments; or the charging protection circuit control method described in any of the foregoing embodiments.

[0037] According to some embodiments, a fourth aspect of the present application provides an electronic device, including: a processor and a memory, the memory stores a computer program, and when the processor runs the computer program, the charging protection circuit control method described in any of the foregoing embodiments is implemented.

[0038] Before generating a disconnection control signal for controlling a loop that disconnects an AC / DC power converter from charging a load, the output electrical signal of the AC / DC power converter is continuously regulated according to a regulated electrical signal for a preset time, so that the amplitude of the output electrical signal of the AC / DC power converter is reduced, significantly reducing or avoiding the generation of surge spike voltages and charging stresses, avoiding events such as overvoltage protection shutdown or device damage of the AC / DC power converter, and improving the performance and reliability of the charger operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0040] Figure 1 Schematic diagram of the circuit principle of a charging protection circuit provided in the first embodiment of the present application.

[0041] Figure 2 Schematic diagram of the circuit principle of a charging protection circuit provided in the second embodiment of the present application.

[0042] Figure 3 Schematic diagram of the circuit principle of a charging protection circuit provided in the third embodiment of the present application.

[0043] Figure 4 Schematic diagram of the circuit principle of a charging protection circuit provided in the fourth embodiment of the present application.

[0044] Figure 5 Schematic diagram of the circuit principle of a charging protection circuit provided in the fifth embodiment of the present application.

[0045] Figure 6 Schematic diagram of the circuit principle of a charging protection circuit provided in the sixth embodiment of the present application.

[0046] Figure 7 Schematic diagram of the circuit of an AC / DC power converter and a switching control circuit in a charging protection circuit provided in an embodiment of the present application.

[0047] Figure 8 Schematic diagram of the circuit of an adjustment loop in a charging protection circuit provided in an embodiment of the present application.

[0048] Reference Signs and Descriptions:

[0049] 100. Charging protection circuit; 200. Load; 11. AC / DC power converter; 20. Regulation loop; 30. Controller; 31. Digital-to-analog converter; 40. On-off control circuit; 41. Output switching device; 42. Control switching device; 43. Voltage conversion circuit; 21. Voltage loop; 22. Current loop; 51. Output voltage detection circuit; 52. Output current detection circuit; 60. Voltage loop detection circuit; 70. Filter circuit. Specific embodiments

[0050] For ease of understanding of the present application, the present application will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the understanding of the disclosure of the present application is more thorough and comprehensive.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0052] In cases where "including", "having", and "comprising" as described herein are used, unless a clear limiting term such as "only", "consisting of", etc. is used, another component may also be added. Unless otherwise mentioned, terms in the singular form may include the plural form and should not be construed as having a quantity of one.

[0053] It should be understood that although terms such as "first" and "second" may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, the first element may be referred to as the second element, and similarly, the second element may be referred to as the first element.

[0054] In this application, unless otherwise clearly specified and limited, terms such as "connected" and "coupled" should be understood in a broad sense. For example, they may be directly connected or indirectly connected through an intermediate medium, and may be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances. Please refer to Figure 1, in some embodiments of the present application, a charging protection circuit 100 is provided, which includes an AC / DC power converter 11, a switching control circuit 40, an adjustment loop 20, and a controller 30. The AC / DC power converter 11 is configured to provide an output electrical signal for charging to a load 200, and the output electrical signal includes a voltage signal and / or a current signal. The switching control circuit 40 is connected to the AC / DC power converter 11 and is configured to disconnect the charging loop of the AC / DC power converter 11 to the load 200 according to a disconnection control signal. The adjustment loop 20 is connected to the AC / DC power converter 11 and is configured to respond to an adjustment control signal and generate an adjustment electrical signal for reducing the amplitude of the output electrical signal according to the output electrical signal. The controller 30 is connected to both the switching control circuit 40 and the adjustment loop 20 and is configured to: generate an adjustment control signal before generating a disconnection control signal; after continuously adjusting the output electrical signal for a preset time according to the adjustment electrical signal to reduce the amplitude of the output electrical signal, generate a disconnection control signal.

[0055] Exemplarily, please continue to refer to Figure 1 , after the load 200 is electrically connected to the AC / DC power converter 11 in the charger, the AC / DC power converter 11 can provide an output electrical signal for charging to the load 200. The load 200 can be a device or apparatus that needs to be charged, such as an electric vehicle, a household appliance, or a wearable electronic device. Since a charging control loop needs to be configured in these devices or apparatuses to cooperate with the corresponding AC / DC power converter for charging, the charging current of a device with a larger power is generally larger. If the charging loop is directly disconnected, the charging current with a relatively large amplitude instantaneously may have an adverse effect on the device or the charger, and seriously, it may damage the battery life or the charger life. By generating an adjustment control signal by the controller 30 before generating a disconnection control signal for controlling the switching control circuit 40 to disconnect the charging loop of the AC / DC power converter 11 to the load 200; continuously adjusting the output electrical signal of the AC / DC power converter 11 for a preset time according to the adjustment electrical signal, after the amplitude of the output electrical signal of the AC / DC power converter 11 is reduced, generating a disconnection control signal, and disconnecting the charging loop of the AC / DC power converter 11 to the load 200 according to the disconnection control signal, the generation of surge spike voltage and charging stress can be significantly reduced or avoided, the overvoltage protection shutdown or device damage event of the AC / DC power converter 11 can be avoided, and the performance and reliability of the charger operation can be improved.

[0056] Exemplarily, a charger generally includes an AC / DC power converter, and the AC / DC power converter may include an AC / DC power conversion circuit. The core functions of the AC / DC power converter include at least one of voltage conversion, current adaptation, safety isolation, ripple suppression, etc. The AC / DC power converter in the charger can at least convert alternating current (AC, such as mains 220V / 50Hz) into stable direct current (DC, such as 5V / 12V), and its design directly affects the charging efficiency, volume, heat generation, and safety.

[0057] Please refer to Figure 2 , in some embodiments, the adjustment control signal includes a current control signal and / or a voltage control signal, and the voltage control signal includes a positive feedback reference voltage or a negative feedback reference voltage; before generating the disconnection control signal, the controller 30 generates a gradually decreasing positive feedback reference voltage or a gradually increasing negative feedback reference voltage; the adjustment loop 20 includes a voltage loop 21, and the voltage loop 21 is connected to both the AC / DC power converter 11 and the controller 30. The voltage loop 21 continuously adjusts the output electrical signal for a preset time according to the gradually decreasing positive feedback reference voltage or the gradually increasing negative feedback reference voltage. After the amplitude of the output electrical signal decreases, a disconnection control signal is generated, so as to disconnect the charging circuit of the AC / DC power converter 11 to the load 200 according to the disconnection control signal, significantly reducing or avoiding the generation of surge spike voltage and charging stress.

[0058] Please continue to refer to Figure 2 , in some embodiments, the adjustment loop 20 includes a current loop 22, and the current loop 22 is connected to both the AC / DC power converter 11 and the controller 30. The current loop 22 continuously adjusts the current signal for a preset time according to the current control signal. After the amplitude of the output electrical signal of the AC / DC power converter 11 decreases, the controller 30 is triggered to generate a disconnection control signal, so as to disconnect the charging circuit of the AC / DC power converter 11 to the load 200 according to the disconnection control signal, significantly reducing or avoiding the generation of surge spike voltage and charging stress.

[0059] Please refer to Figure 3 , in some embodiments, the charging protection circuit 100 further includes an output voltage detection circuit 51, and the output voltage detection circuit 51 is connected to both the AC / DC power converter 11 and the controller 30. When it detects that the amplitude of the voltage signal decreases, the output voltage detection circuit 51 generates a first indication signal for instructing the controller 30 to generate a disconnection control signal; after detecting that the amplitude of the voltage signal output by the AC / DC power converter 11 decreases through the output voltage detection circuit 51, a first indication signal for instructing the controller 30 to generate a disconnection control signal is generated, so as to significantly reduce or avoid the generation of surge spike voltage and charging stress.

[0060] Please refer toFigure 3 In some embodiments, the charging protection circuit 100 further includes an output current detection circuit 52. The output current detection circuit 52 is connected to both the AC / DC power converter 11 and the controller 30. After detecting a decrease in the amplitude of the current signal, the output current detection circuit 52 generates a second indication signal for instructing the controller 30 to generate a disconnection control signal. After detecting a decrease in the amplitude of the current signal output by the AC / DC power converter 11 through the output current detection circuit 52, a second indication signal for instructing the controller 30 to generate a disconnection control signal is generated, so as to significantly reduce or avoid the generation of surge spike voltages and charging stresses.

[0061] Please continue to refer to Figure 3 In some embodiments, when the output voltage detection circuit 51 detects that the amplitude of the voltage signal decreases and the amplitude is within a preset range, a first indication signal for instructing the controller 30 to generate a disconnection control signal is generated, so as to significantly reduce or avoid the generation of surge spike voltages and charging stresses.

[0062] Please continue to refer to Figure 3 In some embodiments, when the output current detection circuit 52 detects that the amplitude of the current signal decreases and is less than a preset threshold, a second indication signal for instructing the controller 30 to generate a disconnection control signal is generated, so as to significantly reduce or avoid the generation of surge spike voltages and charging stresses.

[0063] Please refer to Figure 4 In some embodiments, the charging protection circuit 100 further includes a voltage loop detection circuit 60. The voltage loop detection circuit 60 is connected to both the voltage loop 21 and the controller 30. After the controller 30 generates a positive feedback reference voltage or a negative feedback reference voltage, when the voltage loop detection circuit 60 detects that the voltage loop 21 is normally activated, a third indication signal for instructing the controller 30 to generate a disconnection control signal is generated. Thus, after the normally activated voltage loop 21 continuously adjusts the output electrical signal for a preset time, when the amplitude of the output electrical signal of the AC / DC power converter 11 decreases, the controller 30 is triggered to generate a disconnection control signal, so as to reduce the surge spike voltage and the charging stress.

[0064] Please continue to refer to Figure 4, in some embodiments, the preset time is a fixed time determined according to historical data of the output electrical signal and / or the regulated electrical signal; the controller 30 also obtains the fixed time before generating the regulated electrical signal, so that after the regulation loop 20 continuously regulates the output electrical signal of the AC / DC power converter 11 for this fixed time, the amplitude of the voltage signal output by the AC / DC power converter 11 is reduced and the amplitude is within a preset range, or the amplitude of the current signal output by the AC / DC power converter 11 is reduced and is less than a preset threshold, thereby significantly reducing or avoiding the generation of surge spike voltages and charging stresses, and improving the performance and reliability of the charger operation.

[0065] Please continue to refer to Figure 4 , in some embodiments, the amplitude of the positive feedback reference voltage or the negative feedback reference voltage is related to the target amplitude of the voltage signal; the target amplitude is greater than the minimum operating voltage amplitude at which the AC / DC power converter 11 operates normally without interruption, which facilitates the regulation loop 20 to linearly decrease the amplitude of the output electrical signal of the AC / DC power converter 11 and avoid the generation of surge spike voltages and charging stresses.

[0066] Please refer to Figure 5 , in some embodiments, the controller 30 includes a digital-to-analog converter 31, and the digital-to-analog converter 31 is used to generate a positive feedback reference voltage or a negative feedback reference voltage, so that the regulation loop 20 adjusts the amplitude of the output electrical signal of the AC / DC power converter 11 to decrease based on the positive feedback reference voltage or the negative feedback reference voltage, and avoid the generation of surge spike voltages and charging stresses.

[0067] In some embodiments, the controller includes a pulse width modulator, and the pulse width modulator is used to generate a positive feedback reference voltage or a negative feedback reference voltage, so that the regulation loop adjusts the amplitude of the output electrical signal of the AC / DC power converter to decrease based on the positive feedback reference voltage or the negative feedback reference voltage, and avoid the generation of surge spike voltages and charging stresses.

[0068] Please continue to refer to Figure 5 , in some embodiments, the charging protection circuit 100 further includes a filter circuit 70, and the filter circuit 70 is connected to both the digital-to-analog converter 31 and the voltage loop 21, or is connected to both the pulse width modulator and the voltage loop 21, and is used to provide the filtered positive feedback reference voltage or the filtered negative feedback reference voltage to the voltage loop 21, to avoid the adverse effects of noise or interference waves on the regulation loop 20, resulting in the AC / DC power converter 11 generating an output electrical signal with an increasing amplitude after continuous regulation by the regulated loop 20, thereby avoiding the occurrence of overvoltage protection shutdown or device damage events of the AC / DC power converter 11.

[0069] In some embodiments, the charging protection circuit further includes a filtering circuit. The filtering circuit is connected to both the pulse width modulator and the voltage loop, and is configured to provide a filtered positive feedback reference voltage or a filtered negative feedback reference voltage to the voltage loop, so as to avoid adverse effects of noise or interference waves on the regulation loop, which may cause the AC / DC power converter after continuous regulation of the regulated loop to generate an output electrical signal with an increased amplitude, thereby avoiding overvoltage protection shutdown or device damage events of the AC / DC power converter.

[0070] Please continue to refer to Figure 5 , in some embodiments, after the controller 30 generates the disconnection control signal and before the AC / DC power converter 11 charges the load 200 again, a positive feedback reference voltage with an amplitude less than a first threshold or a negative feedback reference voltage with an amplitude greater than a second threshold is generated; the first threshold is less than the second threshold to avoid high energy consumption of the regulation loop 20 during the period when the AC / DC power converter 11 does not charge the load 200.

[0071] In some embodiments, the positive feedback reference voltage is positively correlated with the amplitude of the regulation electrical signal, so that the regulation loop can adjust the amplitude of the output electrical signal of the AC / DC power converter to decrease linearly or in a gradient manner according to the positive feedback reference voltage.

[0072] In some embodiments, the negative feedback reference voltage is negatively correlated with the amplitude of the regulation electrical signal, so that the regulation loop can adjust the amplitude of the output electrical signal of the AC / DC power converter to decrease linearly or in a gradient manner according to the negative feedback reference voltage.

[0073] Please refer to Figures 6 - 7 , in some embodiments, the on-off control circuit 40 includes an output switching device 41, a control switching device 42, and a voltage conversion circuit 43. The first end of the output switching device 41 is connected to the DC power supply of the AC / DC power converter 11 and is used as the positive output terminal OUT+ of the charger. The second end of the output switching device 41 is connected to the output end of the current loop 22 and is used as the negative output terminal OUT- of the charger. The third end of the output switching device 41 is connected to the output end of the voltage loop 21. The first end of the control switching device 42 is connected to both the second end and the control end of the output switching device 41. The second end of the control switching device 42 is connected to the third DC power supply V3. The first end of the voltage conversion circuit 43 is connected to the control end of the control switching device 42. The second end of the voltage conversion circuit 43 is grounded. The control end of the voltage conversion circuit 43 is configured to receive the disconnection control signal. The voltage conversion circuit 43 is used to convert the amplitude of the disconnection control signal to a suitable operating voltage amplitude range required by the control switching device 42, so as to turn on the control switching device 42 according to the disconnection control signal, thereby controlling the output switching device 41 to disconnect the charging circuit of the AC / DC power converter 11 to the load 200.

[0074] Please continue to refer to Figures 6 - 7 , in some embodiments, the output switching device 41 includes a first switching transistor Q1 and a second switching transistor Q2. The first end of the first switching transistor Q1 is connected to the first DC power supply V1 of the AC / DC power converter 11; the first end of the second switching transistor Q2 is connected to the second end of the first switching transistor Q1, and the second end of the second switching transistor Q2 is connected to the second DC power supply V2 of the AC / DC power converter 11 and is used as the positive output terminal OUT+ of the AC / DC power converter 11. The control end of the second switching transistor Q2 is connected to the first end of the control switching device 42 and is connected to the control end of the first switching transistor Q1. The first switching transistor Q1 and the second switching transistor Q2 are used to isolate the first DC power supply V1 and the second DC power supply V2, avoiding the adverse effects of the load-side electrical signals on the second DC power supply V2, and also avoiding the adverse effects of the first DC power supply V1 on the load side. Moreover, the first switching transistor Q1 and the second switching transistor Q2 cooperate with each other and work together to improve the working stability and reliability of the charging protection circuit.

[0075] Please continue to refer to Figure 7 , in some embodiments, the control switching device 42 includes a third switching transistor Q3. The first end of the third switching transistor Q3 is connected to the control end of the second switching transistor Q2 and is connected to the first end of the second switching transistor Q2 via a first voltage-dividing resistor R2. The second end of the third switching transistor Q3 is connected to the third DC power supply V3 via a first current-limiting resistor R7. The control end of the third switching transistor Q3 is connected to the first end of the voltage conversion circuit 43 via a second current-limiting resistor R4. The third switching transistor Q3 is used to transmit the disconnection control signal to the first switching transistor Q1 and the second switching transistor Q2, so as to realize the control of disconnecting the charging loop of the AC / DC power converter 11 to the load according to the disconnection control signal.

[0076] Please continue to refer to Figure 7 , in some embodiments, the voltage conversion circuit 43 includes a fourth switching transistor Q4. The first end of the fourth switching transistor Q4 is connected to the control end of the third switching transistor Q3 via a second current-limiting resistor R4. The second end of the fourth switching transistor Q4 is grounded to GND. The control end of the fourth switching transistor Q4 is connected to the disconnection control signal OFF via a third current-limiting resistor R6. The third current-limiting resistor R6 is used to protect the fourth switching transistor Q4 from being adversely affected by the disconnection control signal OFF; the fourth switching transistor Q4 can convert the amplitude of the disconnection control signal OFF to the appropriate working voltage amplitude range required by the control switching device 42.

[0077] Please refer to Figure 8, in some embodiments, the voltage loop includes a first operational amplifier IC1B1. The inverting input terminal of the first operational amplifier IC1B1 is sequentially connected to the first DC power supply V1 of the AC / DC power converter 11 via a fourth current-limiting resistor R10 and a fifth current-limiting resistor R9. The non-inverting input terminal of the first operational amplifier IC1B1 is connected to the voltage control signal V-Ctrl via a sixth current-limiting resistor R12. The voltage control signal V-Ctrl includes a positive feedback reference voltage or a negative feedback reference voltage. Among them, the connection node of the fourth current-limiting resistor R10 and the fifth current-limiting resistor R9 is used as the output terminal Vsense1 of the voltage loop. The inverting input terminal of the first operational amplifier IC1B1 is sequentially connected to the ground terminal SGND via the fourth current-limiting resistor R10 and a resistor R11. The non-inverting input terminal of the first operational amplifier IC1B1 receives a positive feedback reference voltage or a negative feedback reference voltage. The inverting input terminal of the first operational amplifier IC1B1 is sequentially connected to the first DC power supply V1 of the AC / DC power converter 11 via the fourth current-limiting resistor R10 and the fifth current-limiting resistor R9. The connection node of the fourth current-limiting resistor R10 and the fifth current-limiting resistor R9 is used as the output terminal Vsense1 of the voltage loop 21, so as to continuously adjust the output electrical signal to reduce the amplitude of the output electrical signal.

[0078] Please continue to refer to Figure 8 , in some embodiments, the current loop includes a second operational amplifier IC1B2. The inverting input terminal of the second operational amplifier IC1B2 is sequentially connected to the current signal Isen via a seventh current-limiting resistor R14 and an eighth current-limiting resistor R15. The non-inverting input terminal of the second operational amplifier IC1B2 is connected to the current control signal I-Ctrl via a ninth current-limiting resistor R16. Among them, the connection node of the seventh current-limiting resistor R14 and the eighth current-limiting resistor R15 is connected to the controller 30, so that after the non-inverting input terminal of the second operational amplifier IC1B2 receives the adjustment control signal provided by the controller 30, a current adjustment signal Isense for continuously adjusting the output electrical signal of the AC / DC power converter 11 is output via the inverting input terminal and the seventh current-limiting resistor R14.

[0079] Please continue to refer to Figure 8 , in some embodiments, the non-inverting input terminal of the second operational amplifier IC1B2 is grounded to GND via a capacitor C4. The capacitor C4 is used to filter out the AC noise signal mixed in the current control signal I-Ctrl. The non-inverting input terminal of the first operational amplifier IC1B1 is grounded to GND via a capacitor C3. The capacitor C3 is used to filter out the AC noise signal in the voltage control signal V-Ctrl.

[0080] Please continue to refer to Figure 8, in some embodiments, the output terminal of the first operational amplifier IC1B1 is connected to the cathode of the diode D1, the anode of the diode D1 is connected to the cathode of the light-emitting diode O1A, the output terminal of the second operational amplifier IC1B2 is connected to the cathode of the diode D2, the anode of the diode D2 is connected to the cathode of the light-emitting diode O1A, and the anode of the light-emitting diode O1A is connected to the third DC power supply V3 via the resistor R13.

[0081] Please continue to refer to Figure 7 , in some embodiments, the first DC power supply V1 is grounded to GND via the capacitor C2, and the capacitor C2 is used to protect the first DC power supply V1. The connection node of the first end of the second switching transistor Q2 and the second end of the first switching transistor Q1 is connected to the third DC power supply V3 via the capacitor C1, and the capacitor C1 is used to protect the third switching transistor Q3. The control terminal of the third switching transistor Q3 is sequentially connected to the third DC power supply V3 via the second current-limiting resistor R4 and the resistor R8.

[0082] Please continue to refer to Figure 7 , in some embodiments, the second DC power supply V2 is grounded via the resistor R2 and the resistor R3 in sequence. The connection node of the resistor R2 and the resistor R3 is used to be connected to the connection terminal 1 of the controller for outputting the detection voltage signal Vsense2. The grounded terminal of the resistor R3 is also connected to the negative input terminal OUT- of the load via the resistor R5. The output terminal of the resistor R5 is used to output the current signal Isen.

[0083] Please continue to refer to Figure 8 , in some embodiments, the connection terminal 1 of the controller is used to connect the detection voltage signal Vsense2, the connection terminal 2 of the controller is used to connect the disconnection control signal OFF, the connection terminal 3 of the controller is used to connect the output terminal Vsense1 of the voltage loop 21, the connection terminal 4 of the controller is used to connect the current control signal I-Ctrl, the connection terminal 5 of the controller is used to connect the current regulation signal Isense, the connection terminal 6 of the controller is used to connect the voltage control signal V-Ctrl, and the connection terminal 7 of the controller is grounded to GND.

[0084] In some embodiments, a charging protection circuit control method is provided, including:

[0085] Step S20: Generate an adjustment control signal before generating the disconnection control signal;

[0086] Step S40: Control the adjustment loop to generate an adjustment electrical signal according to the adjustment control signal, and the adjustment electrical signal is used to adjust the amplitude of the output electrical signal for charging provided by the AC / DC power converter to the load to decrease;

[0087] Step S60: Continuously adjust the output electrical signal for a preset time according to the adjustment electrical signal, so that after the amplitude of the output electrical signal decreases, a disconnection control signal is generated;

[0088] Step S80: Control the on-off control circuit to disconnect the loop for the AC / DC power converter to charge the load according to the disconnection control signal.

[0089] Specifically, before generating the disconnection control signal for controlling the on-off control circuit to disconnect the loop for the AC / DC power converter to charge the load, a regulation control signal is generated; the output electrical signal of the charger is continuously adjusted for a preset time according to the adjustment electrical signal, so that after the amplitude of the output electrical signal of the AC / DC power converter decreases, a disconnection control signal is generated, and the loop for the charger to charge the load is disconnected according to the disconnection control signal, significantly reducing or avoiding the generation of surge peak voltage and charging stress, and avoiding the occurrence of charger overvoltage protection shutdown or device damage events, improving the performance and reliability of the charger operation.

[0090] In some embodiments, the regulation control signal includes at least one of a current control signal, a positive feedback reference voltage, or a negative feedback reference voltage; before generating the disconnection control signal, a gradually decreasing positive feedback reference voltage or a gradually increasing negative feedback reference voltage is generated; according to the gradually decreasing positive feedback reference voltage or the gradually increasing negative feedback reference voltage, the regulation loop is controlled to continuously adjust the output electrical signal for a preset time, and then a disconnection control signal is generated. By controlling the regulation loop to continuously adjust the output electrical signal for a preset time according to the gradually decreasing positive feedback reference voltage or the gradually increasing negative feedback reference voltage, after the output electrical signal of the AC / DC power converter gradually decreases to a preset value, a disconnection control signal is generated, and then the loop for the charger to charge the load is disconnected according to the disconnection control signal, significantly reducing or avoiding the generation of surge peak voltage and charging stress.

[0091] In some embodiments, after the regulation loop is controlled to continuously adjust the current signal for a preset time according to the current control signal, so that the amplitude of the output electrical signal of the charger decreases, a disconnection control signal is generated, and then the loop for the charger to charge the load is disconnected according to the disconnection control signal, significantly reducing or avoiding the generation of surge peak voltage and charging stress.

[0092] In some embodiments, a charger is provided, including: the charging protection circuit described in any of the foregoing embodiments; or the charging protection circuit control method described in any of the foregoing embodiments.

[0093] In some embodiments, an electronic device is provided, including: the charging protection circuit described in any of the foregoing embodiments; or the charging protection circuit control method described in any of the foregoing embodiments.

[0094] In some embodiments, an electronic device is provided, including: a processor and a memory. The memory stores a computer program, and when the processor runs the computer program, it implements the charging protection circuit control method described in any of the foregoing embodiments.

[0095] Before generating a disconnection control signal for controlling the disconnection of the loop for the charger to charge the load, the output electrical signal of the charger is continuously adjusted according to the adjustment electrical signal for a preset time, so that the amplitude of the output electrical signal of the charger is reduced, significantly reducing or avoiding the generation of surge spike voltages and charging stresses, and avoiding the occurrence of charger overvoltage protection shutdown or device damage events, thereby improving the performance and reliability of the charger operation.

[0096] The electronic device is, for example but not limited to, consumer electronic products, home electronic products, electric vehicles, financial terminal products and other suitable types of electronic products. Consumer electronic products such as mobile phones, tablet computers, laptop computers, desktop monitors, all-in-one computers, etc. Home electronic products such as smart door locks, televisions, refrigerators, wearable devices, etc. Financial terminal products such as ATMs, terminals for self-service business handling, etc.

[0097] For the specific limitations of the charging protection circuit control method in the above embodiments, reference may be made to the limitations on the charging protection circuit in the foregoing text, which will not be elaborated herein.

[0098] To verify the effect of this embodiment, we conducted the following experiment: Use an electric vehicle charger with a rated power of 200W to connect a 48V lead-acid battery for testing. Connect the charger and the lead-acid battery and turn on the charger for charging. During the charging process, trigger the shutdown protection device of the electric vehicle charger to start working through a control signal. Observe and record the changes in the output voltage and current of the charger, as well as the cut-off timing of the preset time T. The experimental results include: During the shutdown process of the charger, the output voltage decreases smoothly without sudden voltage surges. At the same time, the output current also gradually decreases until it tends to zero. There is no sharp rebound in the voltage on the output capacitor after the output switching device is turned off. The cut-off timing of the preset time T is accurate and consistent with the preset value. The measured voltage on the output capacitor remains low after shutdown.

[0099] Through the above experiments, it is proved that the charging protection circuit and its control method provided in this embodiment can effectively perform preprocessing before the charger is turned off, protecting the charger and its connected devices from the impact of instantaneous voltage or current. At the same time, the device has a simple structure, comprehensive functions, is safe and reliable, and is applicable to various electric vehicle charger products.

[0100] It should be understood that, unless otherwise clearly stated herein, there is no strict order limit for the execution of the described steps, and these steps can be executed in other orders. Moreover, at least a part of the described steps may include multiple sub-steps or multiple stages. These sub-steps or stages do not necessarily need to be executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or in turn with at least a part of other steps or sub-steps or stages of other steps.

[0101] In some embodiments, the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the steps of the charging protection circuit control method described in the above embodiments.

[0102] In some embodiments, the present application further provides a computer program product, including a computer program. When the computer program is executed by a processor, it implements the steps of the charging protection circuit control method described in the above embodiments.

[0103] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it may include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the various embodiments provided in the present application may include non-volatile and / or volatile memories.

[0104] Please note that the above embodiments are for illustrative purposes only and do not imply any limitation to the present invention.

[0105] Each embodiment in this specification is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other.

[0106] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0107] The above-described embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A charging protection circuit, characterized in that, Comprising: An AC / DC power converter that provides an output electrical signal for charging to a load, the output electrical signal including a voltage signal and / or a current signal; An on-off control circuit connected to the AC / DC power converter to disconnect the circuit for the AC / DC power converter to charge the load according to a disconnection control signal; An adjustment loop connected to the AC / DC power converter, responsive to an adjustment control signal, and generating an adjustment electrical signal for adjusting the amplitude of the output electrical signal to decrease according to the output electrical signal; A controller connected to both the on-off control circuit and the adjustment loop, generating the adjustment control signal before generating the disconnection control signal; continuously adjusting the output electrical signal according to the adjustment electrical signal for a preset time, so that after the amplitude of the output electrical signal decreases, generating the disconnection control signal for controlling the operation of the on-off control circuit.

2. The charging protection circuit according to claim 1, wherein The adjustment control signal includes at least one of a current control signal, a positive feedback reference voltage, or a negative feedback reference voltage; Before generating the disconnection control signal, the controller generates a gradually decreasing positive feedback reference voltage or a gradually increasing negative feedback reference voltage.

3. The charging protection circuit according to claim 2, wherein The adjustment loop includes: A voltage loop connected to both the AC / DC power converter and the controller, and triggering the controller to generate the disconnection control signal after continuously adjusting the voltage signal for a preset time according to the gradually decreasing positive feedback reference voltage or the gradually increasing negative feedback reference voltage.

4. The charging protection circuit according to claim 3, wherein The adjustment loop includes: A current loop connected to both the AC / DC power converter and the controller, and triggering the controller to generate the disconnection control signal after continuously adjusting the current signal for a preset time according to the current control signal.

5. The charging protection circuit according to claim 1, wherein It further includes an output voltage detection circuit and / or an output current detection circuit; The output voltage detection circuit is connected to both the AC / DC power converter and the controller, and generates a first indication signal indicating the controller to generate the disconnection control signal when detecting that the amplitude of the voltage signal decreases; The output current detection circuit is connected to both the AC / DC power converter and the controller, and generates a second indication signal indicating the controller to generate the disconnection control signal when detecting that the amplitude of the current signal decreases.

6. The charging protection circuit according to claim 5, characterized in that, When the output voltage detection circuit detects that the amplitude of the voltage signal decreases and the amplitude is within a preset range, generating the first indication signal; Or When the output current detection circuit detects that the amplitude of the current signal decreases and is less than a preset threshold, generating the second indication signal.

7. The charging protection circuit according to claim 3, characterized in that It further includes: A voltage loop detection circuit connected to both the voltage loop and the controller, and generating a third indication signal indicating the controller to generate the disconnection control signal when detecting that the voltage loop is normally activated after the controller generates the positive feedback reference voltage or the negative feedback reference voltage.

8. The charging protection circuit according to claim 1, wherein The preset time is a fixed time determined according to historical data of the output electrical signal and / or the adjustment electrical signal; Before generating the regulation electrical signal, the controller obtains the fixed time.

9. The charging protection circuit according to claim 2, wherein The magnitude of the positive feedback reference voltage or the negative feedback reference voltage is associated with the target magnitude of the voltage signal; the target magnitude is greater than the minimum operating voltage magnitude at which the AC / DC power converter operates normally without interruption.

10. The charging protection circuit according to claim 3, wherein The controller includes: A digital-to-analog converter, connected to the regulation loop, generating the positive feedback reference voltage or the negative feedback reference voltage.

11. The charging protection circuit according to claim 10, characterized in that The controller includes: A pulse width modulator, connected to the regulation loop, generating the positive feedback reference voltage or the negative feedback reference voltage.

12. The charging protection circuit according to claim 11, wherein, It further includes: A filter circuit, connected to both the digital-to-analog converter and the voltage loop, or connected to both the pulse width modulator and the voltage loop, providing the filtered positive feedback reference voltage or the filtered negative feedback reference voltage to the voltage loop.

13. The charging protection circuit according to claim 2, wherein After generating the disconnection control signal and before the AC / DC power converter charges the load again, the controller generates the positive feedback reference voltage with a magnitude less than a first threshold or the negative feedback reference voltage with a magnitude greater than a second threshold; the first threshold is less than the second threshold.

14. The charging protection circuit according to any one of claims 2-13, characterized in that, The positive feedback reference voltage is positively correlated with the magnitude of the regulation electrical signal; or The negative feedback reference voltage is negatively correlated with the magnitude of the regulation electrical signal.

15. The charging protection circuit according to any one of claims 4-13, characterized in that, The on-off control circuit includes: An output switching device, with its first end connected to a DC power supply and serving as the positive output terminal of the charger, its second end connected to the output end of the current loop and serving as the negative output terminal of the charger, and its third end connected to the output end of the voltage loop; A control switching device, with its first end connected to both the second end and the control end of the output switching device, and its second end connected to a third DC power supply; A voltage conversion circuit, with its first end connected to the control end of the control switching device, its second end grounded, and its control end receiving the disconnection control signal.

16. The charging protection circuit according to claim 15, wherein The output switching device includes: A first switching transistor, with its first end connected to a first DC power supply; A second switching transistor, with its first end connected to the second end of the first switching transistor, its second end connected to a second DC power supply and serving as the positive output terminal of the charger, and its control end connected to the first end of the control switching device and connected to the control end of the first switching transistor.

17. The charging protection circuit according to claim 16, wherein The control switching device includes: A third switching transistor, with its first end connected to the control end of the second switching transistor and connected to the first end of the second switching transistor via a first voltage-dividing resistor, its second end connected to a third DC power supply via a first current-limiting resistor, and its control end connected to the first end of the voltage conversion circuit via a second current-limiting resistor.

18. The charging protection circuit according to claim 17, wherein The voltage conversion circuit includes: A fourth switching transistor, with its first end connected to the control end of the third switching transistor via the second current-limiting resistor, its second end grounded, and its control end connected to the disconnection control signal via a third current-limiting resistor.

19. The charging protection circuit according to any one of claims 3-13, characterized in that, The voltage loop includes: A first operational amplifier, the inverting input terminal is sequentially connected to a first DC power supply via a fourth current-limiting resistor and a fifth current-limiting resistor, and the non-inverting input terminal is connected to the positive feedback reference voltage or the negative feedback reference voltage via a sixth current-limiting resistor; wherein, the connection node of the fourth current-limiting resistor and the fifth current-limiting resistor serves as the output terminal of the voltage loop.

20. The charging protection circuit according to any one of claims 2-13, characterized in that, The current loop includes: A second operational amplifier, the inverting input terminal is sequentially connected to the current signal via a seventh current-limiting resistor and an eighth current-limiting resistor, and the non-inverting input terminal is connected to the current control signal via a ninth current-limiting resistor; wherein, the connection node of the seventh current-limiting resistor and the eighth current-limiting resistor is connected to the controller.

21. A method for controlling a charging protection circuit, characterized in that, Including: Before generating the disconnection control signal, generate an adjustment control signal; According to the adjustment control signal, control the adjustment loop to generate an adjustment electrical signal, and the adjustment electrical signal adjusts the amplitude of the output electrical signal for charging provided by the AC / DC power converter to the load to decrease; According to the adjustment electrical signal, continuously adjust the output electrical signal for a preset time, so that after the amplitude of the output electrical signal decreases, generate a disconnection control signal; According to the disconnection control signal, control the on-off control circuit to disconnect the loop for the AC / DC power converter to charge the load.

22. The charging protection circuit control method according to claim 21, wherein The adjustment control signal includes at least one of a current control signal, a positive feedback reference voltage or a negative feedback reference voltage; Before generating the disconnection control signal, generate a gradually decreasing positive feedback reference voltage, or a gradually increasing negative feedback reference voltage; According to the gradually decreasing positive feedback reference voltage or the gradually increasing negative feedback reference voltage, control the adjustment loop to continuously adjust the voltage signal for a preset time, and then generate the disconnection control signal; Or According to the current control signal, control the adjustment loop to continuously adjust the current signal for a preset time, and then generate the disconnection control signal.

23. An electronic device, characterized in that, The electronic device includes the charging protection circuit according to any one of claims 1-20; or The electronic device includes a processor and a memory, the memory stores a computer program, and when the processor runs the computer program, it implements the charging protection circuit control method according to claim 21 or 22.

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