Charging protection circuit

Abstract

The utility model relates to a charging protection circuit, which comprises an on-off control circuit and an adjusting circuit, and is characterized in that the on-off control circuit is connected with a charging power supply and is used for disconnecting a loop for charging a battery by the charging power supply under the condition that a disconnection control signal is received; and the adjusting circuit is connected with the on-off control circuit and is used for adjusting the amplitude of the charging signal provided by the on-off control circuit to the battery before the off control signal is generated, so that surge peak voltage and charging stress can be obviously reduced or avoided, and the working performance and reliability of the charging power supply are improved.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, and in particular to a charging protection circuit. Background Technology

[0002] As an important tool for modern urban transportation, the battery life of electric vehicles has always been a key concern for users. Proper charging methods can not only extend battery life but also ensure stable performance of the electric vehicle.

[0003] However, in traditional technology, when the output of an electric vehicle charger needs to be turned off during normal charging, the method of directly turning off the output switching device is usually used to stop charging. This can easily lead to surge voltage spikes inside the charger, putting great stress on the internal circuitry of the charger, and even causing the charger to shut down due to overvoltage protection or damage to the devices, seriously reducing the performance and reliability of the charger. Utility Model Content

[0004] Therefore, it is necessary to provide a charging protection circuit to address the problems mentioned above in the background technology. By continuously adjusting the amplitude of the output electrical signal of the charging power supply to reduce it before disconnecting the charging circuit from the charging power supply to the battery, the surge voltage and charging stress can be significantly reduced or avoided, thereby improving the performance and reliability of the charging power supply.

[0005] The first aspect of this application provides a charging protection circuit connected between a battery and a charging power source, including an on / off control circuit and an adjustment circuit. The on / off control circuit is connected to the charging power source and the battery, and is used to disconnect the charging circuit from the charging power source to the battery when a disconnection control signal is received. The adjustment circuit is connected to the on / off control circuit and is used to reduce the amplitude of the charging signal provided to the battery via the on / off control circuit before the disconnection control signal is generated.

[0006] The charging protection circuit in the above embodiments reduces or avoids surge voltage spikes and charging stress by adjusting the amplitude of the charging signal provided by the charging power supply to the battery through the on / off control circuit before generating the disconnection control signal for controlling the on / off control circuit to disconnect the charging power supply to the battery charging circuit. This avoids overvoltage protection shutdown or device damage events, and improves the performance and reliability of the charging power supply.

[0007] In some embodiments, the regulating circuit includes a regulating loop and a controller. The regulating loop is connected to the on / off control circuit and is used to reduce the amplitude of the charging signal provided by the charging power supply to the battery via the on / off control circuit upon receiving a regulating control signal. The controller is connected to both the on / off control circuit and the regulating loop and is used to generate a regulating control signal before generating a disconnection control signal. By generating the regulating control signal before generating the disconnection control signal, the regulating loop reduces the amplitude of the charging signal provided by the on / off control circuit to the battery.

[0008] In some embodiments, the charging protection circuit further includes an AC / DC power converter and an output current detection circuit. The AC / DC power converter is used to convert the electrical energy provided by the charging power supply into a DC signal. The output voltage detection circuit is connected to both the charging power supply and the controller, and is used to generate a first indication signal to instruct the controller to generate a disconnection control signal when the amplitude of the charging signal is detected to decrease.

[0009] In some embodiments, the charging protection circuit further includes an output current detection circuit; the output current detection circuit is connected to both the AC / DC power converter and the controller, and is used to generate a second indication signal to instruct the controller to generate a disconnection control signal when a decrease in the amplitude of the charging signal is detected. This can significantly reduce or avoid surge voltage spikes and charging stress.

[0010] In some embodiments, the controller includes a digital-to-analog converter connected to a regulation loop for generating a positive feedback reference voltage or a negative feedback reference voltage; the positive feedback reference voltage or the negative feedback reference voltage is used to reduce the amplitude of the charging signal provided to the battery by the on / off control circuit.

[0011] In some embodiments, the controller includes a pulse width modulator connected to an adjustment loop for generating a positive feedback reference voltage or a negative feedback reference voltage, which is used to reduce the amplitude of the charging signal supplied to the battery by the on / off control circuit.

[0012] In some embodiments, the charging protection circuit further includes a filtering circuit, which is connected to both the digital-to-analog converter and the adjustment loop, or to both the pulse width modulator and the adjustment loop. The filtering circuit provides a filtered positive feedback reference voltage or a filtered negative feedback reference voltage to the adjustment loop. This prevents noise or interference waves from adversely affecting the adjustment loop, thus avoiding the generation of an output signal with increased amplitude after continuous adjustment by the loop, and preventing overvoltage protection shutdown or device damage.

[0013] In some embodiments, the on / off control circuit includes an output switching device, a control switching device, and a voltage conversion circuit. The first terminal of the output switching device is connected to a first DC power supply and serves as the positive output terminal of the charger; the second terminal is connected to the output terminal of the current loop and serves as the negative output terminal of the charging power supply; and the third terminal is connected to the output terminal of the voltage loop. The first terminal of the control switching device is connected to both the second terminal and the control terminal of the output switching device, and the second terminal is connected to the third DC power supply. The first terminal of the voltage conversion circuit is connected to the control terminal of the control switching device, and the second terminal is grounded. The control terminal is used to receive a disconnection control signal. The voltage conversion circuit converts the amplitude of the disconnection control signal to a suitable operating voltage range required by the control switching device, thereby enabling the control switching device to be turned on according to the disconnection control signal, thus controlling the output switching device to disconnect the charging power supply from the battery charging loop.

[0014] In some embodiments, the output switching device includes a first switching transistor and a second switching transistor. A first terminal of the first switching transistor is connected to a first DC power supply; a first terminal of the second switching transistor is connected to a second terminal of the first switching transistor, and the second terminal is connected to a second DC power supply of the charging power supply and serves as the positive output terminal of the charger. A control terminal is connected to the first terminal of the control switching device and also to the control terminal of the first switching transistor. The first and second switching transistors isolate the first and second DC power supplies, preventing adverse effects from the battery-side electrical signals on the second DC power supply, and also preventing adverse effects from the first DC power supply on the battery side. Furthermore, the first and second switching transistors cooperate and work together to improve the operational stability and reliability of the charging protection circuit.

[0015] In some embodiments, the control switching device includes a third switching transistor. The first terminal of the third switching transistor is connected to the control terminal of the second switching transistor and is also connected to the first terminal of the second switching transistor via a first voltage divider resistor. The second terminal of the third switching transistor is connected to a third DC power supply via a first current-limiting resistor. The control terminal is connected to the first terminal of the voltage conversion circuit via a second current-limiting resistor. The third switching transistor transmits a disconnection control signal to the first and second switching transistors, thus realizing a circuit that controls the disconnection of the charging power supply to the battery based on the disconnection control signal.

[0016] In some embodiments, the voltage conversion circuit includes a fourth switching transistor. The first terminal of the fourth switching transistor is connected to the control terminal of a third switching transistor via a second current-limiting resistor, and the second terminal is grounded. The control terminal is connected to a disconnect control signal via the third current-limiting resistor. The third current-limiting resistor protects the fourth switching transistor from adverse effects caused by the disconnect control signal. The fourth switching transistor can convert the amplitude of the disconnect control signal to a suitable operating voltage range required to control the switching device.

[0017] In some embodiments, a charger is provided, including the charging protection circuit described in any of the foregoing embodiments.

[0018] In some embodiments, an electronic device is provided, including the charging protection circuit described in any of the foregoing embodiments. By reducing the amplitude of the charging signal of the charging power supply before generating a disconnection control signal for controlling the disconnection of the charging power supply from the battery, surge voltage spikes and charging stress are significantly reduced or avoided, preventing overvoltage protection shutdown or device damage events of the charging power supply, thereby improving the performance and reliability of the charging power supply. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other embodiments can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the circuit principle of a charging protection circuit provided in the first embodiment of this application.

[0021] Figure 2a This is a schematic diagram of the circuit principle of a charging protection circuit provided in the second embodiment of this application.

[0022] Figure 2b This is a schematic diagram of the circuit principle of a charging protection circuit provided in the third embodiment of this application.

[0023] Figure 3 This is a schematic diagram of the circuit principle of a charging protection circuit provided in the fourth embodiment of this application.

[0024] Figure 4 This is a schematic diagram of the circuit principle of a charging protection circuit provided in the fifth embodiment of this application.

[0025] Figure 5 This is a schematic diagram of the circuit principle of a charging protection circuit provided in the sixth embodiment of this application.

[0026] Figure 6 This is a schematic diagram of the circuit principle of a charging protection circuit provided in the seventh embodiment of this application.

[0027] Figure 7 This is a circuit diagram of a charging protection circuit and a switching control circuit provided in one embodiment of this application.

[0028] Figure 8 This is a circuit diagram of the adjustment loop in a charging protection circuit provided in one embodiment of this application.

[0029] Figure labels and descriptions:

[0030] 100. Charging protection circuit; 200. Load; 11. AC / DC power converter; 12. Regulation circuit; 20. Regulation loop; 30. Controller; 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. Filtering circuit. Detailed Implementation

[0031] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0033] When using the terms “including,” “having,” and “comprising” as described herein, another component may be added unless explicitly qualifying terms such as “only,” “consisting of,” etc. are used. Unless otherwise stated, singular terms may include plural forms and should not be construed as having a quantity of one.

[0034] It should be understood that although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the scope of this application, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

[0035] In this application, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a direct connection or an indirect connection through an intermediate medium, or they can refer to the internal connection of two elements or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0036] Please refer to Figure 1In some embodiments, a charging protection circuit 100 is provided, including an on / off control circuit 40 and an adjustment circuit 12. The on / off control circuit 40 is connected to a charging power supply and is used to disconnect the charging circuit from the charging power supply to the load 200 when a disconnection control signal is received. The adjustment circuit 12 is connected to the on / off control circuit 40 and is used to reduce the amplitude of the charging signal provided to the load 200 via the on / off control circuit 40 before the disconnection control signal is generated.

[0037] For example, please continue to refer to Figure 1 The charging protection circuit 100 is connected between the battery and the charging power supply. Before the adjustment circuit 12 generates the disconnection control signal for controlling the on / off control circuit 40 to disconnect the charging circuit from the charging power supply to the battery, it reduces the amplitude of the charging signal provided by the charging power supply to the battery through the on / off control circuit 40. This significantly reduces or avoids the generation of surge voltage spikes and charging stress, prevents the charger from shutting down due to overvoltage or damage to components, and improves the performance and reliability of the charger.

[0038] Please refer to Figure 2a In some embodiments, the regulating circuit 12 includes a regulating loop 20 and a controller 30. The regulating loop 20 is connected to the charging power supply and is used to reduce the amplitude of the charging signal provided by the charging power supply to the load 200 upon receiving a regulating control signal. The controller 30 is connected to both the on / off control circuit 40 and the regulating loop 20 and is used to generate a regulating control signal before generating a disconnection control signal. By generating the regulating control signal before generating the disconnection control signal, the controller 30 causes the regulating loop 20 to reduce the amplitude of the charging signal provided by the charging power supply to the load 200, such as a battery, via the on / off control circuit 40.

[0039] Please refer to Figure 2b In some embodiments, a charging protection circuit 100 is provided, including a charging power supply, an on / off control circuit 40, an adjustment loop 20, and a controller 30. The charging power supply provides an output electrical signal for charging to a load 200, the output electrical signal including a voltage signal and / or a current signal. The on / off control circuit 40 is connected to the charging power supply and is used to disconnect the charging circuit from the charging power supply to the load 200 according to a disconnection control signal. The adjustment loop 20 is connected to the charging power supply and is used to generate an adjustment electrical signal to reduce the amplitude of the output electrical signal according to the output electrical signal in response to the adjustment control signal. The controller 30 is connected to both the on / off control circuit 40 and the adjustment loop 20. The controller 30 generates the adjustment control signal before generating the 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, the controller 30 generates the disconnection control signal.

[0040] For example, please continue to refer to Figure 2bAfter the load 200 is electrically connected to the charging power supply, the charging power supply can provide an output electrical signal for charging to the load 200 via the on / off control circuit 40. The load 200 can be an electric vehicle, household appliance, or wearable electronic device that needs to be charged, or it can be a battery. Since these devices need to be equipped with a charging control circuit to cooperate with the corresponding charging power supply for charging, the higher the power of the device, the larger the charging current. If the charging circuit is directly disconnected, the large instantaneous charging current may have an adverse effect on the device or the charging power supply, and in severe cases, it may damage the battery life or the life of the charging power supply. Before generating a disconnection control signal to control the on / off control circuit 40 to disconnect the charging power supply from the load 200, the controller 30 generates an adjustment control signal. Based on this adjustment signal, the controller continuously adjusts the output signal of the charging power supply for a preset time, so that the amplitude of the output signal of the charging power supply is reduced. Then, the controller generates a disconnection control signal, and based on this disconnection control signal, the charging power supply disconnects the charging power supply from the load 200. This significantly reduces or avoids surge voltage spikes and charging stress, prevents overvoltage protection shutdown of the charging power supply or device damage, and improves the performance and reliability of the charging power supply.

[0041] Please refer to Figure 2b In some embodiments, the adjustment control signal includes a current control signal and / or a voltage control signal, the voltage control signal including a positive feedback reference voltage or a negative feedback reference voltage; the controller 30 is configured to generate a gradually decreasing positive feedback reference voltage or a gradually increasing negative feedback reference voltage before generating a disconnection control signal; the adjustment loop 20 includes a voltage loop 21, which is connected to both the AC / DC power converter 11 and the controller 30, and is configured 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, so that the amplitude of the output electrical signal decreases, and then generate a disconnection control signal, thereby disconnecting the circuit of the AC / DC power converter 11 charging the load 200 according to the disconnection control signal, significantly reducing or avoiding the generation of surge voltage spikes and charging stress.

[0042] Please continue to refer to this. Figure 2b In some embodiments, the regulating loop 20 includes a current loop 22, which 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 so that the amplitude of the output electrical signal of the AC / DC power converter 11 is reduced, and then generates a disconnection control signal. According to the disconnection control signal, the circuit of the AC / DC power converter 11 charging the load 200 is disconnected, which significantly reduces or avoids the generation of surge voltage and charging stress.

[0043] Please refer to Figure 3In some embodiments, the charging protection circuit 100 further includes an output voltage detection circuit 51, which is connected to both the AC / DC power converter 11 and the controller 30. When the output voltage detection circuit 51 detects a decrease in the amplitude of the voltage signal, it generates a first indication signal to instruct the controller 30 to generate a disconnection control signal. After the output voltage detection circuit 51 detects a decrease in the amplitude of the voltage signal output by the AC / DC power converter 11, it generates another first indication signal to instruct the controller 30 to generate a disconnection control signal, thereby significantly reducing or avoiding the generation of surge voltage spikes and charging stress.

[0044] Please refer to Figure 3 In some embodiments, the charging protection circuit 100 further includes an output current detection circuit 52, which is connected to both the AC / DC power converter 11 and the controller 30. When the output current detection circuit 52 detects a decrease in the amplitude of the current signal, it generates a second indication signal to instruct the controller 30 to generate a disconnection control signal. By detecting a decrease in the amplitude of the current signal output by the AC / DC power converter 11, and then generating a second indication signal to instruct the controller 30 to generate a disconnection control signal, the generation of surge voltage spikes and charging stress can be significantly reduced or avoided.

[0045] Please continue to refer to this. 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, it generates a first indication signal to instruct the controller 30 to generate a disconnection control signal, so as to significantly reduce or avoid the generation of surge voltage spikes and charging stress.

[0046] Please continue to refer to this. 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, it generates a second indication signal to instruct the controller 30 to generate a disconnection control signal, so as to significantly reduce or avoid the generation of surge voltage spikes and charging stress.

[0047] 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, it generates a third indication signal to instruct the controller 30 to generate a disconnection control signal. Thus, after the normally activated voltage loop 21 continuously adjusts the output electrical signal for a preset time, the amplitude of the output electrical signal of the AC / DC power converter 11 is reduced, and then a disconnection control signal is generated to reduce surge voltage spikes and charging stress.

[0048] Please continue to refer to this. Figure 4 In some embodiments, the AC / DC power converter 11 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, and ripple suppression. The AC / DC power converter in the charger can at least convert alternating current (AC, such as 220V / 50Hz mains power) into stable direct current (DC, such as 5V / 12V). Its design directly affects charging efficiency, size, heat generation, and safety. The preset time is a fixed time determined based on historical data of the output electrical signal and / or the regulating electrical signal. Before generating the regulating electrical signal, the controller 30 acquires the fixed time, so that the regulating loop 20 continuously adjusts the output electrical signal of the charging power supply. After the fixed time, the amplitude of the voltage signal output by the charging power supply is reduced and the amplitude is within a preset range, or the amplitude of the current signal output by the charging power supply is reduced and is less than a preset threshold, thereby significantly reducing or avoiding the generation of surge voltage spikes and charging stress, and improving the performance and reliability of the charging power supply.

[0049] Please continue to refer to this. Figure 4 In some embodiments, the amplitude of the positive feedback reference voltage or the negative feedback reference voltage is associated with the target amplitude of the voltage signal; the target amplitude is greater than the minimum operating voltage amplitude of the AC / DC power converter 11 for normal and uninterrupted operation, so that the regulating loop 20 can adjust the output electrical signal amplitude of the AC / DC power converter 11 to decrease linearly, thereby avoiding the generation of surge voltage spikes and charging stress.

[0050] Please refer to Figure 5 In some embodiments, the controller 30 includes a digital-to-analog converter 31, which generates a positive feedback reference voltage or a negative feedback reference voltage, thereby enabling the regulation loop 20 to adjust the amplitude of the output electrical signal of the AC / DC power converter 11 based on the positive feedback reference voltage or the negative feedback reference voltage, thereby avoiding the generation of surge voltage spikes and charging stress.

[0051] In some embodiments, the controller includes a pulse width modulator for generating a positive feedback reference voltage or a negative feedback reference voltage, thereby enabling the regulation loop to adjust the amplitude of the charging power supply output signal based on the positive or negative feedback reference voltage to reduce the amplitude and avoid surge voltage spikes and charging stress.

[0052] Please continue to refer to this. Figure 5In some embodiments, the charging protection circuit 100 further includes a filter circuit 70, which is connected to both the digital-to-analog converter 31 and the voltage loop 21, or to both the pulse width modulator and the voltage loop 21. The filter circuit 70 is used to provide the voltage loop 21 with a filtered positive feedback reference voltage or a filtered negative feedback reference voltage to avoid noise or interference waves from adversely affecting the regulation loop 20, which would cause the AC / DC power converter 11 after continuous regulation by the regulation loop 20 to generate an output electrical signal with increased amplitude, thereby avoiding overvoltage protection shutdown of the AC / DC power converter 11 or device damage events.

[0053] In some embodiments, the charging protection circuit further includes a filtering circuit, which is connected to both the pulse width modulator and the voltage loop. The filtering circuit is used to provide the voltage loop with a filtered positive feedback reference voltage or a filtered negative feedback reference voltage to avoid noise or interference waves from adversely affecting the regulation loop. This prevents the charging power supply after continuous regulation from generating an output electrical signal with increased amplitude, thereby avoiding overvoltage protection shutdown or device damage events.

[0054] Please continue to refer to this. Figure 5 In some embodiments, after generating a disconnect control signal and before the AC / DC power converter 11 recharges the load 200, the controller 30 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 the regulation loop 20 consuming more power when the AC / DC power converter 11 is not charging the load 200.

[0055] In some embodiments, the positive feedback reference voltage is positively correlated with the amplitude of the regulating electrical signal, so that the regulating loop adjusts the amplitude of the charging power supply output electrical signal to decrease linearly or gradually according to the positive feedback reference voltage.

[0056] In some embodiments, the negative feedback reference voltage is negatively correlated with the amplitude of the regulating electrical signal, so that the regulating loop adjusts the amplitude of the charging power supply output electrical signal to decrease linearly or gradually according to the negative feedback reference voltage.

[0057] Please refer to Figures 6-7In some embodiments, the on / off control circuit 40 includes an output switch 41, a control switch 42, and a voltage conversion circuit 43. The first terminal of the output switch 41 is connected to the DC power supply of the AC / DC power converter 11 and serves as the positive output terminal OUT+ of the charger. The second terminal of the output switch 41 is connected to the output terminal of the current loop 22 and serves as the negative output terminal OUT- of the charger. The third terminal of the output switch 41 is connected to the output terminal of the voltage loop 21. The first terminal of the control switch 42 is connected to both the second terminal and the control terminal of the output switch 41, and the second terminal of the control switch 42 is connected to the third DC power supply V3. The first terminal of the voltage conversion circuit 43 is connected to the control terminal of the control switch 42, and the second terminal of the voltage conversion circuit 43 is grounded. The control terminal of the voltage conversion circuit 43 is used to receive a disconnection control signal. The voltage conversion circuit 43 converts the amplitude of the disconnection control signal to a suitable operating voltage range required by the control switch 42, thereby enabling the control switch 42 to be turned on according to the disconnection control signal, thus controlling the output switch 41 to disconnect the charging circuit from the load 200.

[0058] Please continue to refer to this. Figures 6-7 In some embodiments, the output switching device 41 includes a first switch Q1 and a second switch Q2. The first terminal of the first switch Q1 is connected to the first DC power supply V1; the first terminal of the second switch Q2 is connected to the second terminal of the first switch Q1, and the second terminal of the second switch Q2 is connected to the second DC power supply V2 and serves as the positive output terminal OUT+ of the charger. The control terminal of the second switch Q2 is connected to the first terminal of the control switching device 42 and also to the control terminal of the first switch Q1. The first switch Q1 and the second switch Q2 isolate the first DC power supply V1 and the second DC power supply V2, preventing the load-side electrical signal from adversely affecting the second DC power supply V2, and also preventing the first DC power supply V1 from adversely affecting the load side. Furthermore, the first switch Q1 and the second switch Q2 cooperate with each other, improving the operational stability and reliability of the charging protection circuit.

[0059] Please continue to refer to this. Figure 7 In some embodiments, the control switching device 42 includes a third switch Q3. The first terminal of the third switch Q3 is connected to the control terminal of the second switch Q2 and is also connected to the first terminal of the second switch Q2 via a first voltage divider resistor R2. The second terminal of the third switch Q3 is connected to the third DC power supply V3 via a first current-limiting resistor R7. The control terminal of the third switch Q3 is connected to the first terminal of the voltage conversion circuit 43 via a second current-limiting resistor R4. The third switch Q3 is used to transmit a disconnection control signal to the first switch Q1 and the second switch Q2, thereby realizing a loop that controls the disconnection of the charging power supply to charge the load according to the disconnection control signal.

[0060] Please continue to refer to this. Figure 7 In some embodiments, the voltage conversion circuit 43 includes a fourth switch Q4. The first terminal of the fourth switch Q4 is connected to the control terminal of the third switch Q3 via a second current-limiting resistor R4. The second terminal of the fourth switch Q4 is grounded to GND. The control terminal of the fourth switch Q4 is connected to the disconnection control signal OFF via a third current-limiting resistor R6. The third current-limiting resistor R6 protects the fourth switch Q4 from adverse effects caused by the disconnection control signal OFF. The fourth switch Q4 can convert the amplitude of the disconnection control signal OFF to the appropriate operating voltage amplitude range required by the control switching device 42.

[0061] Please refer to Figure 8 In some embodiments, the voltage loop includes a first operational amplifier IC1B1. The inverting input of the first operational amplifier IC1B1 is connected to the first DC power supply V1 of the charging power supply via a fourth current-limiting resistor R10 and a fifth current-limiting resistor R9. The non-inverting input of the first operational amplifier IC1B1 is connected to a 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. 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 of the first operational amplifier IC1B1 is connected to the ground terminal SGND via the fourth current-limiting resistor R10 and a resistor R11. The positive or negative feedback reference voltage is received at the positive input terminal of the first operational amplifier IC1B1. The inverting input terminal of the first operational amplifier IC1B1 is connected to the first DC power supply V1 of the charging power supply 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, thereby continuously adjusting the output electrical signal to reduce the amplitude of the output electrical signal.

[0062] Please continue to refer to this. Figure 8 In some embodiments, the current loop includes a second operational amplifier IC1B2. The inverting input of the second operational amplifier IC1B2 is connected to the current signal Isen via a seventh current-limiting resistor R14 and an eighth current-limiting resistor R15. The non-inverting input of the second operational amplifier IC1B2 is connected to the current control signal I-Ctrl via a ninth current-limiting resistor R16. 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 receiving the adjustment control signal provided by the controller 30, the non-inverting input of the second operational amplifier IC1B2 outputs a current adjustment signal Isense for continuously adjusting the output electrical signal of the charger 10 via the inverting input and the seventh current-limiting resistor R14.

[0063] Please continue to refer to this. Figure 8 In some embodiments, the positive input terminal of the second operational amplifier IC1B2 is grounded to GND via capacitor C4, which is used to filter out AC noise signals mixed in the current control signal I-Ctrl. The positive input terminal of the first operational amplifier IC1B1 is grounded to GND via capacitor C3, which is used to filter out AC noise signals in the voltage control signal V-Ctrl.

[0064] Please continue to refer to this. Figure 8 In some embodiments, the output of the first operational amplifier IC1B1 is connected to the cathode of diode D1, the anode of diode D1 is connected to the cathode of light-emitting diode O1A, the output of the second operational amplifier IC1B2 is connected to the cathode of diode D2, the anode of diode D2 is connected to the cathode of light-emitting diode O1A, and the anode of light-emitting diode O1A is connected to the third DC power supply V3 via resistor R13.

[0065] Please continue to refer to this. Figure 7 In some embodiments, the first DC power supply V1 is grounded to GND via capacitor C2, which protects the first DC power supply V1. The connection node between the first terminal of the second switch Q2 and the second terminal of the first switch Q1 is connected to the third DC power supply V3 via capacitor C1, which protects the third switch Q3. The control terminal of the third switch Q3 is connected to the third DC power supply V3 in sequence via the second current-limiting resistor R4 and resistor R8.

[0066] Please continue to refer to this. Figure 7 In some embodiments, the second DC power supply V2 is grounded sequentially via resistors R2 and R3. The connection point of resistors R2 and R3 is used to connect to connection terminal 1 of the controller for outputting a detection voltage signal Vsense2. The grounding terminal of resistor R3 is also connected to the negative input terminal OUT- of the load via resistor R5. The output terminal of resistor R5 is used to output a current signal Isen. OUT+ can be the positive output terminal of the charger, and OUT- can be the negative output terminal of the charger.

[0067] Please continue to refer to this. Figure 8 In some embodiments, the controller's connection terminal 1 is used to connect to the detection voltage signal Vsense2, the controller's connection terminal 2 is used to connect to the disconnect control signal OFF, the controller's connection terminal 3 is used to connect to the output terminal Vsense1 of the voltage loop 21, the controller's connection terminal 4 is used to connect to the current control signal I-Ctrl, the controller's connection terminal 5 is used to connect to the current adjustment signal Isense, the controller's connection terminal 6 is used to connect to the voltage control signal V-Ctrl, and the controller's connection terminal 7 is grounded to GND.

[0068] In some embodiments, an electronic device is provided, including the charging protection circuit described in any of the foregoing embodiments. By reducing the amplitude of the charger's charging signal before generating a disconnection control signal for controlling the disconnection of the charger's circuit to a load such as a battery, surge voltage spikes and charging stress are significantly reduced or avoided, preventing charger overvoltage protection shutdown or device damage events, thereby improving the charger's performance and reliability.

[0069] This electronic device includes, but is not limited to, suitable types of electronic products such as consumer electronics, home electronics, electric vehicles, and financial terminals. Consumer electronics include mobile phones, tablets, laptops, desktop monitors, and all-in-one computers. Home electronics include smart locks, televisions, refrigerators, and wearable devices. Financial terminals include ATMs and self-service terminals.

[0070] To verify the effectiveness of this embodiment, we conducted the following experiment: A 200W rated power electric vehicle charger was connected to a 48V lead-acid battery for testing. The charger and lead-acid battery were connected, and the charger was turned on for charging. During charging, a control signal triggered the electric vehicle charger's shutdown protection device to start working. The changes in the charger's output voltage and current, as well as the cutoff timing of the preset time T, were observed and recorded. The experimental results include: During the charger's shutdown process, the output voltage decreased smoothly without any sudden voltage surges. Simultaneously, the output current also gradually decreased until it approached zero. After the output switching device was turned off, there was no voltage spike on the output capacitor. The cutoff timing of the preset time T was accurate and consistent with the preset value. After shutdown, the voltage measured on the output capacitor remained low.

[0071] The above experiments demonstrate that the charging protection circuit and its control method provided in this embodiment can effectively perform pre-processing before the charger is turned off, protecting the charger and its connected devices from the effects of instantaneous voltage or current surges. Furthermore, this device is simple in structure, comprehensive in function, safe and reliable, and suitable for various electric vehicle charger products.

[0072] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Furthermore, any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory.

[0073] Please note that the above embodiments are for illustrative purposes only and do not imply any limitation on the present invention.

[0074] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0075] The technical features of the embodiments described above can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. The embodiments described above only illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A charging protection circuit, characterized in that, Connected between the battery and the charging power source, the charging protection circuit includes: An on / off control circuit is connected to the charging power supply and the battery. Upon receiving a disconnection control signal, it disconnects the charging circuit from the charging power supply to the battery. An adjustment circuit, connected to the on / off control circuit, reduces the amplitude of the charging signal supplied to the battery via the on / off control circuit before generating the off control signal.

2. The charging protection circuit according to claim 1, characterized in that, The regulating circuit includes: An adjustment loop, connected to the on / off control circuit, reduces the amplitude of the charging signal supplied to the battery via the on / off control circuit upon receiving an adjustment control signal. The controller is connected to both the on / off control circuit and the adjustment loop, and generates the adjustment control signal before generating the off control signal.

3. The charging protection circuit according to claim 2, characterized in that, Also includes: An AC / DC power converter converts the electrical energy provided by the charging power supply into a DC signal. The output voltage detection circuit is connected to both the AC / DC power converter and the controller. When it detects a decrease in the amplitude of the charging signal, it generates a first indication signal that instructs the controller to generate the disconnection control signal.

4. The charging protection circuit according to claim 3, characterized in that, Also includes: The output current detection circuit is connected to both the AC / DC power converter and the controller. When it detects a decrease in the amplitude of the charging signal, it generates a second indication signal that instructs the controller to generate the disconnection control signal.

5. The charging protection circuit according to claim 2, characterized in that, The controller includes: A digital-to-analog converter, connected to the adjustment loop, generates a positive feedback reference voltage or a negative feedback reference voltage; the positive feedback reference voltage or the negative feedback reference voltage reduces the amplitude of the charging signal provided to the battery by the on / off control circuit.

6. The charging protection circuit according to claim 5, characterized in that, The controller includes: A pulse width modulator, connected to the regulation loop, generates a positive feedback reference voltage or a negative feedback reference voltage, which reduces the amplitude of the charging signal provided to the battery by the on / off control circuit.

7. The charging protection circuit according to claim 6, characterized in that, Also includes: The filtering circuit is connected to both the digital-to-analog converter and the adjustment loop, or to both the pulse width modulator and the adjustment loop, and provides the adjustment loop with a filtered positive feedback reference voltage or a filtered negative feedback reference voltage.

8. The charging protection circuit according to any one of claims 2-6, characterized in that, The on / off control circuit includes: The output switching device has a first terminal connected to a first DC power supply and serving as the positive output terminal of the charger, a second terminal connected to the output terminal of the adjustment loop and serving as the negative output terminal of the charger, and a third terminal connected to the output terminal of the adjustment loop. The control switching device has its first terminal connected to both the second terminal and the control terminal of the output switching device, and its second terminal connected to a third DC power supply. The voltage conversion circuit has a first terminal connected to the control terminal of the control switching device, a second terminal grounded, and the control terminal receiving the disconnection control signal.

9. The charging protection circuit according to claim 8, characterized in that, The output switching device includes: The first switching transistor has its first terminal connected to the first DC power supply. The second switching transistor has a first terminal connected to the second terminal of the first switching transistor, a second terminal connected to the second DC power supply and serving as the positive output terminal of the charger, and a control terminal connected to the first terminal of the control switching device and the control terminal of the first switching transistor.

10. The charging protection circuit according to claim 9, characterized in that, The control switching device includes: The third switching transistor has its first terminal connected to the control terminal of the second switching transistor and connected to the first terminal of the second switching transistor via a first voltage divider resistor. Its second terminal is connected to the third DC power supply via a first current limiting resistor, and its control terminal is connected to the first terminal of the voltage conversion circuit via a second current limiting resistor.

11. The charging protection circuit according to claim 10, characterized in that, The voltage conversion circuit includes: The fourth switching transistor has its first terminal connected to the control terminal of the third switching transistor via the second current-limiting resistor, its second terminal grounded, and its control terminal connected to the disconnection control signal via the third current-limiting resistor.

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