Charging control circuit and charging control method

Abstract

The invention discloses a charging control circuit and a control method. The charging control circuit comprises an output module, a voltage control loop, a current control loop and a control module. The control module is coupled with the output module and is configured to receive the output current and the output voltage of the output module; the first input end of the voltage control loop is used for receiving the power supply voltage of the output module, and the second input end is coupled with the first output pin of the control module; the first input end of the current control loop is coupled to the second output pin of the control module, the second input end of the current control loop is coupled to the third output pin of the control module, and the control module is configured to provide a value representing the output current to the first input end of the current control loop; wherein the control module is used for reducing the value at the second input end of the voltage control loop and / or increasing the value at the first input end of the current control loop. The charging control circuit provided by the invention can be prevented from being damaged by hot plug operation.

Description

Technical Field

[0001] The present invention relates to the technical field of chargers, and in particular to a charging control circuit and a charging control method. Background Art

[0002] During the charging process, especially in constant current mode, if a hot-swap operation (i.e., plugging or unplugging the output cable while the battery is powered) occurs suddenly in the charging control circuit, the voltage control loop cannot react quickly enough, causing a sharp rise in the internal output voltage. This can easily generate a large voltage spike, causing a transient voltage or current shock to internal components and potentially damaging the charging control circuit. Because the voltage spike occurs very quickly from unplugging the battery (typically within a few milliseconds or even less), it is crucial to design a charging control circuit that is immune to hot-swap operations. Summary of the Invention

[0003] The present invention provides a charging control circuit and a charging control method, which can avoid damage caused by hot plugging and unplugging operations.

[0004] In a first aspect, an embodiment of the present invention provides a charging control circuit, comprising: an output module, a voltage control loop, a current control loop, and a control module; the control module is coupled to the output module and configured to receive the output current and output voltage of the output module; the voltage control loop has a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal is used to receive the power supply voltage of the output module, and the second input terminal is coupled to the first output pin of the control module, and the control module is configured to provide a reference voltage to the second input terminal of the voltage control loop; the current control loop has a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal is coupled to the second output pin of the control module, and the second input terminal is coupled to the third output pin of the control module, and the control module is configured to provide a value representing the output current to the first input terminal of the current control loop, and provide a reference current to the second input terminal of the current control loop; wherein the control module is used to pull down the value at the second input terminal of the voltage control loop and / or pull up the value at the first input terminal of the current control loop.

[0005] Optionally, the voltage control loop includes a first operational amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor and a second capacitor; the first end of the first resistor is used to receive the power supply voltage of the output module, and the second end of the first resistor is connected to the first end of the second resistor and the first end of the third resistor; the second end of the second resistor is connected to the first input end of the first operational amplifier, and the second end of the third resistor is grounded; the first end of the fourth resistor is connected to the first output pin of the control module, the second end of the fourth resistor is connected to the second input end of the first operational amplifier and the first end of the first capacitor, and the second end of the first capacitor is grounded; the first end of the second capacitor is connected to the first input end of the first operational amplifier, the second end of the second capacitor is connected to the first end of the fifth resistor, and the second end of the fifth resistor is connected to the output end of the first operational amplifier.

[0006] Optionally, the current control loop includes a second operational amplifier, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a third capacitor and a fourth capacitor; the first end of the sixth resistor is connected to the first input terminal of the second operational amplifier, the second end of the sixth resistor is connected to the first end of the seventh resistor, and the second end of the seventh resistor is connected to the second output pin of the control module; the first end of the eighth resistor is connected to the third output pin of the control module, the second end of the eighth resistor is connected to the second input terminal of the second operational amplifier and the first end of the third capacitor, and the second end of the third capacitor is grounded; the first end of the fourth capacitor is connected to the first input terminal of the second operational amplifier, the second end of the fourth capacitor is connected to the first end of the ninth resistor, and the second end of the ninth resistor is connected to the output terminal of the second operational amplifier.

[0007] Optionally, the control module further has a fourth output pin, which is coupled to the second input end of the voltage control loop. The control module is used to provide a low-level voltage control signal to the second input end of the voltage control loop and / or pull down the reference voltage.

[0008] Optionally, the control module further has a fifth output pin, which is coupled to the first input terminal of the current control loop. The control module is used to provide a high-level current control signal to the first input terminal of the current control loop.

[0009] Optionally, the control module is further configured to lower the reference current.

[0010] Optionally, the output module includes a switch circuit and a voltage conversion unit; the voltage conversion unit is coupled to the output ends of the voltage control loop and the current control loop, and the voltage conversion unit is further coupled to the switch circuit.

[0011] Optionally, the control module is further configured to adjust a reference voltage at the second input terminal of the voltage control loop to be greater than the output voltage, and to adjust a difference between the reference voltage and the output voltage to a preset value.

[0012] In a second aspect, an embodiment of the present invention provides a charging control method, which is applied to the charging control circuit provided by any embodiment of the present invention. The charging control method includes: collecting the output voltage and output current of the output module and controlling the constant current output of the output module through a current control loop or controlling the constant voltage output of the output module through a voltage control loop; if the change in the output voltage and / or output current meets the preset conditions, the value at the second input end of the voltage control loop is lowered and / or the value at the first input end of the current control loop is raised to control the output module to stop working.

[0013] Optionally, the preset conditions include: within a set time, the output voltage increases by a magnitude greater than a first set value; and / or, within a set time, the output current decreases by a magnitude greater than a third set value; and the step of lowering the value at the second input of the voltage control loop includes providing a low-level voltage control signal to the second input of the voltage control loop and / or lowering a reference voltage. The step of raising the value at the first input of the current control loop includes providing a high-level current control signal to the first input of the current control loop.

[0014] Optionally, the charging control method further includes: if the output voltage rises by more than a first set value within a set time, and / or the output current drops by more than a second set value within a set time, lowering the reference current of the current control loop.

[0015] Optionally, the charging control method further includes: when the change in the output voltage and / or output current does not meet a preset condition, controlling the reference voltage of the second input terminal of the voltage control loop to be greater than the output voltage, and controlling the difference between the reference voltage and the output voltage to be a preset value.

[0016] Optionally, the charging control method further comprises: delaying a preset time after the change of the output voltage and / or the output current meets a preset condition, and restoring the value at the second input terminal of the voltage control loop and / or the value at the first input terminal of the current control loop after the delay of the preset time.

[0017] Optionally, the charging control method also includes: delaying a preset time after the change in the output voltage and / or output current meets a preset condition, and after the preset delay time, restoring the value at the second input terminal of the voltage control loop and / or the value at the first input terminal of the current control loop, and also restoring the reference current of the current control loop.

[0018] The charging control circuit provided by an embodiment of the present invention includes an output module, a voltage control loop, a current control loop and a control module. The control module collects the output voltage and output current of the output module, and when the change in the output voltage and / or output current meets a preset condition, the value at the second input end of the voltage control loop is lowered and / or the value at the first input end of the current control loop is raised to control the output module to stop working. This can promptly respond and control the voltage that rises sharply after the output interface of the charging control circuit is hot-plugged and unplugged, eliminate or reduce the possibility of spike voltage generated at the output interface of the charging control circuit, reduce the stress of electronic components, and further reduce the risk of damage to the charging control circuit due to hot-plug operations, thereby improving the safety and reliability of the charging control circuit.

[0019] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 1 is a schematic structural diagram of a charging control circuit provided by an embodiment of the present invention;

[0022] Figure 2 Provided is a schematic diagram of the structure of a current control loop in one embodiment;

[0023] Figure 3 Provided is a schematic diagram of the structure of a voltage control loop in one embodiment;

[0024] Figure 4 This is a structural diagram of another charging control circuit provided by an embodiment of the present invention;

[0025] Figure 5 This is a structural diagram of another charging control circuit provided by an embodiment of the present invention;

[0026] Figure 6 is a flow chart of a charging control method provided by an embodiment of the present invention;

[0027] Figure 7 This is a measurement diagram of the output voltage waveform during hot plugging and unplugging of a charging control circuit in related technology;

[0028] Figure 8This is a measurement diagram of the output voltage waveform during the hot plug and unplug process of the charging control circuit provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0030] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment". The term "coupled" means that it can be a direct connection or an indirect connection.

[0031] Figure 1 FIG. 1 is a schematic diagram of a charging control circuit provided by an embodiment of the present invention. Figure 1 As shown, the charging control circuit includes: an output module 10 , a voltage control loop 20 , a current control loop 30 and a control module 40 .

[0032] The control module 40 is coupled to the output module 10 and configured to receive the output current and output voltage of the output module 10 .

[0033] The voltage control loop 20 has a first input terminal, a second input terminal and an output terminal. The first input terminal is used to receive the power supply voltage V1 of the output module 10, and the second input terminal is coupled to the first output pin of the control module 40. The control module 40 is configured to provide a reference voltage V-Ctrl to the second input terminal of the voltage control loop 20.

[0034] The current control loop 30 has a first input terminal, a second input terminal and an output terminal. The first input terminal is coupled to the second output pin of the control module 40, and the second input terminal is coupled to the third output pin of the control module 40. The control module 40 is configured to provide a value representing the output current to the first input terminal of the current control loop 30 and to provide a reference current I-Ctrl to the second input terminal of the current control loop 30.

[0035] The control module 40 is configured to lower the value at the second input terminal of the voltage control loop 20 and / or raise the value at the first input terminal of the current control loop 30 .

[0036] Specifically, the output module 10 is the final output part of the charging control circuit, providing power to an external load or charging device.

[0037] The voltage control loop 20 is used to regulate the output voltage of the output module 10. The output voltage of the output module 10 is sampled and formed into a feedback voltage, which is compared with the reference voltage V-Ctrl provided by the control module 40. The output voltage is then adjusted based on the comparison result to maintain it near a stable value set by the reference voltage according to the voltage divider ratio. If the feedback voltage of the output voltage is higher than the reference voltage, that is, the actual output voltage is higher than the output voltage value set by the reference voltage, the voltage control loop 20 will cause the output module 10 to reduce the output voltage through a feedback signal. Conversely, if the feedback voltage of the output voltage is lower than the reference voltage, the voltage control loop 20 will cause the output module 10 to increase the output voltage through a feedback signal. In one embodiment, the voltage control loop 20 can regulate the output voltage by providing a feedback signal to the AC / DC power converter 1022 via an optocoupler 1021, etc., to ensure that the output voltage is stable at the level set by the reference voltage.

[0038] The current control loop 30 is used to regulate the output current of the output module 10. By comparing the output current of the output module 10 with the set value of the reference current I-Ctrl provided by the control module 40, the output current is adjusted according to the comparison result so that it remains near the output current set by the desired reference current. If the feedback voltage formed after sampling the output current is higher than the reference voltage provided by the reference current I-Ctrl, that is, the actual output current is higher than the output current value set by the reference current, the current control loop 30 will cause the output module 10 to reduce the output current through a feedback signal; conversely, if the feedback voltage formed after sampling the output current is lower than the reference voltage provided by the reference current I-Ctrl, the current control loop 30 will cause the output module 10 to increase the output current through a feedback signal. In one embodiment, the current control loop 30 can achieve output current regulation by providing a feedback signal to the AC / DC power converter 1022 through an optocoupler 1021, etc., to ensure that the output current is stable at the value set by the reference current.

[0039] The control module 40 may include a microcontroller. Optionally, the control module 40 may include a single chip microcomputer, a digital signal processor (DSP) or a field programmable gate array (FPGA).

[0040] In one embodiment, the control module 40 can collect the output voltage and output current of the output module 10 and control the output module 10 to output a constant current through the current control loop 30 or control the output module 10 to output a constant voltage through the voltage control loop 20. In other words, the output mode of the charging control circuit can be a constant current output mode or a constant voltage output mode.

[0041] In one embodiment, when the load is a constant input voltage load, the user can select the constant voltage output mode. When the load is a constant current input load, the user can select the constant current output mode.

[0042] In one embodiment, illustratively, the load may be an electric vehicle battery.

[0043] In one embodiment, at the initial stage of charging, the output voltage is low, and the charging control circuit charges the load in a constant current output mode. The current control loop 30 ensures that the output current is stable at the output current value set by the reference current I-Ctrl, thereby avoiding damage to the load caused by excessive current and improving the charging efficiency. As charging progresses, the output voltage gradually rises, but the output current remains constant until the output voltage reaches a preset constant voltage threshold. When the output voltage rises to the set constant voltage threshold, the charging control circuit switches to a constant voltage output mode. At this time, the output voltage is controlled by the voltage control loop 20 to be stable at the output voltage value set by the reference voltage V-Ctrl, and the output current gradually decreases as the battery is saturated until the output current reaches the cut-off current, indicating that charging is complete.

[0044] In one embodiment, when the output voltage rises by more than a first set value within a set time, the control module 40 determines that a hot plug / unplug operation has occurred on the output interface of the charging control circuit. At this point, the control module 40 lowers the value at the second input of the voltage control loop 20, or raises the value at the first input of the current control loop 30, or lowers the value at the second input of the voltage control loop 20 and raises the value at the first input of the current control loop 30, thereby stopping the output module 10. In one embodiment, the voltage control loop 20 or the current control loop 30 can provide a stop feedback signal to the AC / DC power converter 1022 via the optocoupler 1021, thereby stopping the output module 10.

[0045] In another embodiment, when the output current decreases by more than a second set value within a set time, the control module 40 determines that a hot plug / unplug operation has occurred at the output interface of the charging control circuit. In this case, the control module 40 lowers the value at the second input terminal of the voltage control loop 20, or raises the value at the first input terminal of the current control loop 30, or both lowers the value at the second input terminal of the voltage control loop 20 and raises the value at the first input terminal of the current control loop 30, thereby controlling the output module 10 to stop operating. In one embodiment, the voltage control loop 20 or the current control loop 30 can provide a stop feedback signal to the AC / DC power converter 1022 via the optocoupler 1021, thereby causing the output module 10 to stop operating.

[0046] In another embodiment, when the output voltage increases by more than a first set value and the output current decreases by more than a second set value within a set time, the control module 40 determines that a hot plug / unplug operation has occurred at the output interface of the charging control circuit. In this case, the control module 40 lowers the value at the second input of the voltage control loop 20, or raises the value at the first input of the current control loop 30, or lowers the value at the second input of the voltage control loop 20 and raises the value at the first input of the current control loop 30, thereby controlling the output module 10 to stop operating. In one embodiment, the voltage control loop 20 or the current control loop 30 can provide a stop feedback signal to the AC / DC power converter 1022 via the optocoupler 1021, thereby causing the output module 10 to stop operating.

[0047] In one embodiment, the control module 40 may provide a low-level voltage control signal to the second input terminal of the voltage control loop 20 to lower the value at the second input terminal of the voltage control loop 20 .

[0048] In another embodiment, the control module 40 may control the reference voltage of the second input terminal of the voltage control loop 20 to be 0, so as to lower the value at the second input terminal of the voltage control loop 20 .

[0049] In another embodiment, the control module 40 may provide a low-level voltage control signal to the second input terminal of the voltage control loop 20 and control the reference voltage of the second input terminal of the voltage control loop 20 to be 0 to pull down the value at the second input terminal of the voltage control loop 20 .

[0050] In one embodiment, the control module 40 may provide a high-level current control signal to the first input terminal of the current control loop 30 to increase the value at the first input terminal of the current control loop 30 .

[0051] The charging control circuit provided by the embodiment of the present invention includes an output module 10, a voltage control loop 20, a current control loop 0 and a control module 40. The output voltage and output current of the output module 10 are collected by the control module 40, and when the change in the output voltage and / or output current meets a preset condition, the value at the second input terminal of the voltage control loop 20 is lowered and / or the value at the first input terminal of the current control loop 30 is raised to control the output module 10 to stop working. This can promptly respond to and control the voltage that rises sharply after the output interface of the charging control circuit is hot-plugged and unplugged, eliminate or reduce the possibility of spike voltage generated at the output interface of the charging control circuit, reduce the stress of electronic components, and thereby reduce the risk of damage to the charging control circuit due to hot-plug operation, thereby improving the safety and reliability of the charging control circuit.

[0052] Figure 2 The following is a schematic diagram of the structure of a voltage control loop in one embodiment. Figure 2 As shown, optionally, the voltage control loop 20 includes a first operational amplifier U1 , a first resistor R1 , a second resistor R2 , a third resistor R3 , a fourth resistor R4 , a fifth resistor R5 , a first capacitor C1 , and a second capacitor C2 .

[0053] A first end of the first resistor R1 is used to receive the supply voltage V1 of the output module 10 , and a second end of the first resistor R1 is connected to a first end of the second resistor R2 and a first end of the third resistor R3 .

[0054] A second end of the second resistor R2 is connected to the first input end of the first operational amplifier U1 , and a second end of the third resistor R3 is grounded.

[0055] A first end of the fourth resistor R4 is connected to the first output pin of the control module 40 , a second end of the fourth resistor R4 is connected to the second input end of the first operational amplifier U1 and the first end of the first capacitor C1 , and a second end of the first capacitor C1 is grounded.

[0056] A first end of the second capacitor C2 is connected to the first input end of the first operational amplifier U1 , a second end of the second capacitor C2 is connected to the first end of the fifth resistor R5 , and a second end of the fifth resistor R5 is connected to the output end of the first operational amplifier U1 .

[0057] Specifically, the first resistor R1, the second resistor R2, and the third resistor R3 jointly divide the supply voltage V1. The divided voltage is transmitted to the first input terminal of the first operational amplifier U1, thereby providing the first input terminal of the first operational amplifier U1 with a feedback voltage of the output voltage of the output module 10.

[0058] The fourth resistor R4 plays a role in current limiting and also contributes to stable signal transmission.

[0059] The fifth resistor R5 and the second capacitor C2 together form a feedback loop, which can feed back the output signal of the first operational amplifier U1 to its first input terminal, thereby adjusting the output of the first operational amplifier U1 to achieve the purpose of stabilizing the output voltage and reducing voltage fluctuations.

[0060] In some implementations, a first end of the first resistor R1 serves as a first input end of the voltage control loop 20 , and a first end of the fourth resistor R4 serves as a second input end of the voltage control loop 20 .

[0061] In some implementations, the first input terminal of the first operational amplifier U1 serves as the first input terminal of the voltage control loop 20 , and the second input terminal of the first operational amplifier U1 serves as the second input terminal of the voltage control loop 20 .

[0062] Optionally, continue to refer to Figure 2 The voltage control loop 20 further includes a first diode D1 , a cathode of the first diode D1 being connected to the output end of the first operational amplifier U1 , and an anode of the first diode D1 being connected to the output end of the voltage control loop 20 .

[0063] In some embodiments, when the change in output voltage and / or output current meets a preset condition, the control module 40 lowers the value at the second input of the voltage control loop 20, causing the voltage at the second input of the first operational amplifier U1 to be lower than the voltage at its first input. This in turn causes the first operational amplifier U1 to quickly output a low level, turning on the first diode D1 to control the output module 10 to stop operating, thereby stopping the output voltage from rising. This embodiment, by lowering the value at the second input of the voltage control loop 20, causes the first operational amplifier U1 to quickly output a low level, thereby quickly responding to the hot swap action.

[0064] Figure 3 The following is a schematic diagram of the structure of the current control loop in one embodiment. Figure 3 As shown, optionally, the current control loop 30 includes a second operational amplifier U2, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a third capacitor C3 and a fourth capacitor C4.

[0065] A first end of the sixth resistor R6 is connected to the first input end of the second operational amplifier U2 , a second end of the sixth resistor R6 is connected to the first end of the seventh resistor R7 , and a second end of the seventh resistor R7 is connected to the second output pin of the control module 40 .

[0066] A first end of the eighth resistor R8 is connected to the third output pin of the control module 40 , a second end of the eighth resistor R8 is connected to the second input end of the second operational amplifier U2 and a first end of the third capacitor C3 , and a second end of the third capacitor C3 is grounded.

[0067] A first end of the fourth capacitor C4 is connected to the first input end of the second operational amplifier U2 , a second end of the fourth capacitor C4 is connected to the first end of the ninth resistor R9 , and a second end of the ninth resistor R9 is connected to the output end of the second operational amplifier U2 .

[0068] Specifically, the sixth resistor R6 and the seventh resistor R7 work together to divide the signal output from the second output pin of the control module 40 and input it to the first input terminal of the second operational amplifier U2 to provide a value representing the output current to the first input terminal of the second operational amplifier U2.

[0069] The eighth resistor R8 serves to limit the current, and transmits the signal outputted from the third output pin of the control module 40 to the second input terminal of the second operational amplifier U2.

[0070] The ninth resistor R9 and the fourth capacitor C4 together form a feedback loop, which feeds back the output signal of the second operational amplifier U2 to the first input terminal thereof, so as to adjust the output of the second operational amplifier U2 to achieve precise control of the current.

[0071] The third capacitor C3 can filter out high-frequency noise and interference in the output signal of the third output pin of the control module 40, so that the signal input to the second input terminal of the second operational amplifier U2 is more stable and pure.

[0072] In some embodiments, the second end of the seventh resistor R7 serves as the first input end of the current control loop 30 , and the first end of the eighth resistor R8 serves as the second input end of the current control loop 30 .

[0073] In some embodiments, the first input terminal of the second operational amplifier U1 serves as the first input terminal of the current control loop 30 , and the second input terminal of the second operational amplifier U1 serves as the second input terminal of the current control loop 30 .

[0074] Optionally, continue to refer to Figure 3 The current control loop 30 further includes a second diode D2 , a cathode of the second diode D2 is connected to the output end of the second operational amplifier U2 , and an anode of the second diode D2 serves as the output end of the current control loop 30 .

[0075] In some embodiments, when the change in output voltage and / or output current meets a preset condition, control module 40 raises the value at the first input of current control loop 30, causing the voltage at the second input of second operational amplifier U2 to be lower than the voltage at its first input. This in turn causes second operational amplifier U2 to quickly output a low level, turning on second diode D2 to control output module 10 to stop operating, thereby stopping the output voltage from rising. This embodiment, by raising the value at the first input of current control loop 30, causes second operational amplifier U2 to quickly output a low level, thereby quickly responding to hot swapping.

[0076] Figure 4 FIG. 1 is a structural diagram of another charging control circuit provided by an embodiment of the present invention. Figure 4 As shown, optionally, the control module 40 also has a fourth output pin, which is coupled to the second input terminal of the voltage control loop 20. The control module 40 is used to provide a low-level voltage control signal V-Pulse to the second input terminal of the voltage control loop 20 and / or pull down the reference voltage V-Ctrl.

[0077] Specifically, when the charging control circuit is operating normally, the first input of the first operational amplifier U1 is connected to the divided voltage of the output module 10 (i.e., the sampled value of the output voltage), and the second input normally receives the reference voltage V-Ctrl. When in constant voltage mode and the output voltage is normal, the reference voltage V-Ctrl is approximately equal to the divided output voltage, the output of the first operational amplifier U1 is in a balanced state between high and low levels, and the output module 10 is operating normally.

[0078] In one embodiment, when the output interface of the charging control circuit experiences a hot plug or unplug action, the output voltage and / or output current change. When the control module 40 detects that the change in output voltage and / or output current meets a preset condition, it outputs a low-level voltage control signal V-Pulse via the fourth output pin, forcibly lowering the voltage at the second input terminal of the first operational amplifier U1. This voltage is reduced to less than the voltage at the first input terminal, causing the first operational amplifier U1 to output a low-level signal, thereby controlling the output module 10 to stop operating and thereby stopping the output voltage from rising. This embodiment rapidly responds to the hot plug action by lowering the voltage at the second input terminal of the first operational amplifier U1.

[0079] In one embodiment, when the control module 40 detects that the change in the output voltage and / or output current meets a preset condition, the control module 40 lowers the reference voltage V-Ctrl (such as the output module 10 controls the reference voltage V-Ctrl to 0), so that the voltage at the second input terminal of the first operational amplifier U1 is less than the voltage at its first input terminal, and the first operational amplifier U1 outputs a low level to control the output module 10 to stop working, thereby stopping the output voltage from rising.

[0080] In one embodiment, when the control module 40 detects that the change in the output voltage and / or output current meets a preset condition, the control module 40 outputs a low-level voltage control signal V-Pulse through the fourth output pin and pulls down the reference voltage V-Ctrl, so that the voltage at the second input terminal of the first operational amplifier U1 is less than the voltage at its first input terminal. The first operational amplifier U1 outputs a low level to control the output module 10 to stop working, thereby stopping the output voltage from rising.

[0081] Optionally, continue to refer to Figure 4 The control module 40 further has a fifth output pin, which is coupled to the first input terminal of the current control loop 30. The control module 40 is used to provide a high-level current control signal I-Pulse to the first input terminal of the current control loop.

[0082] Specifically, the fourth output pin and the fifth output pin of the control module 40 are normally configured to be in a high-impedance input state, ie, no signal is applied to the outside.

[0083] When the charging control circuit is operating normally, the first input terminal of the second operational amplifier U2 receives the feedback current signal, and the second input terminal normally receives the reference current I-Ctrl. When in constant current mode and the output current is normal, the reference current I-Ctrl is approximately equal to the feedback current, the output of the second operational amplifier U2 is in a balanced state between high and low levels, and the output module 10 operates normally.

[0084] In one embodiment, when the control module 40 detects a hot-swap operation on the output interface of the charging control circuit, that is, when the change in output voltage and / or output current meets a preset condition, it outputs a high-level current control signal I-Pulse via the fifth output pin, forcibly raising the voltage at the first input terminal of the second operational amplifier U2. This causes the reference current I-Ctrl to be less than the feedback current, i.e., the voltage at the second input terminal of the second operational amplifier U2 is less than the voltage at its first input terminal. The second operational amplifier U2 then outputs a low-level signal, thereby controlling the output module 10 to stop operating and thereby stopping the output voltage from rising. This embodiment rapidly responds to the hot-swap operation by raising the voltage at the first input terminal of the second operational amplifier U2.

[0085] Optionally, the control module 40 is further configured to lower the reference current I-Ctrl. Specifically, when the change in the output voltage and / or output current satisfies a preset condition, the control module 40 lowers the reference current I-Ctrl (e.g., the output module 10 controls the reference current I-Ctrl to be 0), causing the voltage at the second input terminal of the second operational amplifier U2 to be less than the voltage at its first input terminal. The second operational amplifier U2 then outputs a low level, thereby controlling the output module 10 to stop operating, thereby stopping the output voltage from rising.

[0086] In one embodiment, when the change in the output voltage and / or output current meets a preset condition, the control module 40 outputs a high-level current control signal I-Pulse through the fifth output pin, and pulls down the reference current I-Ctrl (such as the output module 10 controls the reference current I-Ctrl to be 0), so that the voltage at the second input terminal of the second operational amplifier U2 is less than the voltage at its first input terminal, and the second operational amplifier U2 outputs a low level to control the output module 10 to stop working, thereby stopping the output voltage from rising.

[0087] Figure 5 FIG. 1 is a structural diagram of another charging control circuit provided by an embodiment of the present invention. Figure 5 As shown, optionally, the output module 10 includes a switch circuit 101 and a voltage conversion unit 102 .

[0088] The voltage conversion unit 102 is coupled to the output terminals of the voltage control loop 20 and the current control loop 30 . The voltage conversion unit 102 is further coupled to the switch circuit 101 .

[0089] Specifically, the voltage conversion unit 102 is used to convert alternating current (AC) into direct current (DC). The voltage conversion unit 102 can also stop outputting voltage according to the output value of the current control loop 30 or the voltage control loop 20 .

[0090] In one embodiment, the voltage conversion unit 102 includes a photocoupler 1021 and an AC / DC power converter 1022. The photocoupler 1021 implements electrical isolation and safely transmits the control signal on the low-voltage side (i.e., the output value of the voltage control loop 20 or the current control loop 30) to the AC / DC power converter 1022 on the high-voltage side. The AC / DC power converter 1022 can be a flyback converter, a forward converter, an LLC resonant converter, or a full-bridge converter. The AC / DC power converter 1022 is used to convert alternating current into direct current and provide a power supply voltage V1 for the switching circuit 101. In other words, the power supply voltage V1 of the output module 10 is the output voltage of the AC / DC power converter 1022.

[0091] The switch circuit 101 is used to control the on and off of the charging output, and can be implemented by power devices such as Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) or Insulated Gate Bipolar Transistor (IGBT).

[0092] When the output voltage / current is within the normal range, the LED cathode of the photocoupler 1021 enters a balanced state between high and low levels, the AC / DC power converter 1022 outputs a DC voltage normally, and the charging control circuit outputs a voltage normally.

[0093] When the output voltage rises by more than a first set value and the output current falls by more than a second set value within a set time, either the voltage control loop 20 or the current control loop 30 outputs a low level, forcibly pulling the cathode potential of the LED of the optocoupler 1021 down to a low level. This creates a forward bias voltage between the anode and cathode of the LED, turning the LED on and emitting light. The phototransistor, triggered by light, turns on, reducing its equivalent resistance. The optocoupler output is connected to the enable pin or feedback pin of the AC / DC power converter 1022. If connected to the enable pin, the AC / DC power converter 1022 suspends operation and stops outputting power after the phototransistor turns on. If connected to the feedback pin, the AC / DC power converter enters current limiting or shutdown mode after the phototransistor turns on. After the AC / DC power converter 1022 stops supplying power, the supply voltage V1 of the switching circuit 101 stops rising, and the output voltage no longer increases.

[0094] In some embodiments, the switching circuit 101 includes a switching transistor M1, a fifth capacitor C5, a tenth resistor R10, an eleventh resistor R11, and a sampling resistor Rs. The first end of the fifth capacitor C5 is connected to the first output terminal of the AC / DC power converter 1022, and the second end of the fifth capacitor is connected to the second output terminal of the AC / DC power converter 1022 and the first end of the sampling resistor Rs. The gate of the switching transistor M1 is connected to the control module 40, the first electrode of the switching transistor M1 is connected to the first end of the fifth capacitor C5, and the second electrode of the switching transistor M1 is connected to the positive output terminal of the switching circuit 101. The first end of the tenth resistor R10 is connected to the second electrode of the switching transistor M1, the second end of the tenth resistor R10 is connected to the first end of the eleventh resistor R11, and the second end of the eleventh resistor R11 is connected to the first end of the sampling resistor Rs. The second end of the sampling resistor Rs is connected to the negative output terminal of the switching circuit 101.

[0095] The first input pin of the control module 40 is connected to the second end of the sampling resistor Rs for collecting the output current of the output module 10. The second input pin of the control module 40 is connected to the second end of the tenth resistor R10, and the third input pin of the control module 40 is connected to the second end of the first resistor R1 for collecting the output voltage of the output module 10.

[0096] In one embodiment, the control module 40 is further configured to adjust the reference voltage V-Ctrl at the second input of the voltage control loop 20 to be greater than the output voltage, and to adjust the difference between the reference voltage V-Ctrl and the output voltage to a predetermined value. This configuration allows the voltage control loop 20 to be activated by a small increase in the output voltage during hot plugging, further accelerating the issuance of a signal to the voltage conversion unit 102 to stop outputting power (i.e., to prevent the supply voltage V1 from continuing to rise).

[0097] Based on the same inventive concept, an embodiment of the present invention further provides a charging control method, which is applied to the charging control circuit provided by any embodiment of the present invention. Figure 6 This is a flow chart of a charging control method provided by an embodiment of the present invention. The method of this embodiment can be executed by a control module of a charging control circuit, and the control module can be implemented in software and / or hardware.

[0098] like Figure 6 As shown, the charging control method includes:

[0099] S101 , collecting the output voltage and output current of the output module 10 and controlling the output module 10 to output a constant current through the current control loop 30 or controlling the output module 10 to output a constant voltage through the voltage control loop 20 .

[0100] Specifically, continue to refer to Figure 1During normal charging, the control module 40 periodically (e.g., every 0.1 ms) collects the output voltage and output current. The voltage control loop 20 compares the output voltage of the output module 10 with a reference voltage V-Ctrl provided by the control module 40 and adjusts the output voltage based on the comparison result, maintaining it near the desired stable value. If the output voltage is higher than the reference voltage, the voltage control loop 20 reduces the output voltage; conversely, if the output voltage is lower than the reference voltage, the voltage control loop 20 increases the output voltage. In other words, the voltage control loop 20 controls the output module 10 to output a constant voltage. The current control loop 30 compares the output current of the output module 10 with a reference current I-Ctrl provided by the control module 40 and adjusts the output current based on the comparison result, maintaining it near the desired stable value. If the output current is higher than the reference voltage, the current control loop 30 reduces the output current; conversely, if the output current is lower than the reference voltage, the current control loop 30 increases the output current. In other words, the current control loop 30 controls the output module 10 to output a constant current.

[0101] S102 : If the change in the output voltage and / or output current meets a preset condition, the value at the second input terminal of the voltage control loop 20 is lowered and / or the value at the first input terminal of the current control loop 30 is raised to control the output module 10 to stop working.

[0102] Specifically, the preset conditions include that within a set time, the output voltage increases by a magnitude greater than a first set value, and / or, within a set time, the output current decreases by a magnitude greater than a second set value.

[0103] It should be noted that detecting that the output voltage rise is greater than the first set value within the set time can also be understood as detecting that the output voltage rise reaches the first set value within the set time. Detecting hot-swap removal requires both rapid detection and interference immunity to ensure rapid and accurate protection. Generally, the shorter the time from removal to detection, the more timely and effective protection is. Therefore, the set time is generally preferably less than 1 millisecond.

[0104] The first and second set values can be determined by measuring the change in output voltage or output current after hot-swap removal, as well as the ripple of the output voltage or output current during normal operation, component variations, and reasonable tolerances. Generally, the first set value is greater than the maximum ripple voltage during operation and less than one-tenth of the maximum output voltage. A smaller first set value results in faster protection activation, but the probability of false triggering increases, so it should be set to a reasonable value. The second set value is greater than the maximum ripple current during operation. For example, when charging at a 48V output, the maximum output ripple voltage is 0.5V, including under normal interference conditions. Therefore, the first set value can be set to 1V. Within 1 millisecond after hot-swap removal (without protection), if the output voltage rises by more than 1V every 0.05 milliseconds (i.e., the output voltage rises by 1V within 0.05 milliseconds), then the set time can be set to 0.1 millisecond, taking into account component variations and fault tolerances. If the rise exceeds 1V within 0.1 second, the set time can be set to 0.2 milliseconds, and so on.

[0105] In one embodiment, when the output voltage rises by more than a first set value within a set time, the control module 40 determines that a hot plug-in or unplugging action occurs at the output interface of the charging control circuit. At this time, the control module 40 lowers the value at the second input terminal of the voltage control loop 20, or the control module 40 raises the value at the first input terminal of the current control loop 30, or the control module 40 lowers the value at the second input terminal of the voltage control loop 20 and raises the value at the first input terminal of the current control loop 30, so as to control the output module 10 to stop working.

[0106] In another embodiment, when the decrease in the output current is greater than a second set value within a set time, the control module 40 determines that a hot plug-in or unplugging action occurs at the output interface of the charging control circuit. At this time, the control module 40 lowers the value at the second input terminal of the voltage control loop 20, or the control module 40 raises the value at the first input terminal of the current control loop 30, or the control module 40 lowers the value at the second input terminal of the voltage control loop 20 and raises the value at the first input terminal of the current control loop 30, so as to control the output module 10 to stop working.

[0107] In another embodiment, when the output voltage rises by more than a first set value and the output current falls by more than a second set value within a set time, the control module 40 determines that a hot plug-in or unplugging action occurs at the output interface of the charging control circuit. At this time, the control module 40 lowers the value at the second input terminal of the voltage control loop 20, or the control module 40 raises the value at the first input terminal of the current control loop 30, or the control module 40 lowers the value at the second input terminal of the voltage control loop 20 and raises the value at the first input terminal of the current control loop 30, so as to control the output module 10 to stop working.

[0108] In one embodiment, the control module 40 may provide a low-level voltage control signal to the second input terminal of the voltage control loop 20 to lower the value at the second input terminal of the voltage control loop 20 .

[0109] In another embodiment, the control module 40 may pull down the reference voltage V-Ctrl. Exemplarily, the reference voltage at the second input terminal of the voltage control loop 20 is controlled to be 0, so as to pull down the value at the second input terminal of the voltage control loop 20.

[0110] In yet another embodiment, the control module 40 may provide a low-level voltage control signal to the second input terminal of the voltage control loop 20 and pull down the reference voltage V-Ctrl to lower the value at the second input terminal of the voltage control loop 20 .

[0111] In one embodiment, the control module 40 may provide a high-level current control signal to the first input terminal of the current control loop 30 to increase the value at the first input terminal of the current control loop 30 .

[0112] In one embodiment, if the output voltage rises by more than a first set value within a set time, and / or the output current drops by more than a second set value within a set time, the reference current I-Ctrl of the current control loop 30 may be lowered.

[0113] The control method also includes: when the change of the output voltage and / or output current does not meet the preset conditions, controlling the reference voltage V-Ctrl of the second input terminal of the voltage control loop 20 to be greater than the output voltage, and controlling the difference between the reference voltage V-Ctrl and the output voltage to be a preset value.

[0114] Specifically, continue to refer to Figure 5 When the charging control circuit is operating in the constant current mode and the change in the output voltage and / or output current does not meet the preset conditions, the reference voltage V-Ctrl of the voltage control loop 20 is dynamically adjusted so that the difference between the reference voltage V-Ctrl and the output voltage is a preset value. As a result, when hot plugging and unplugging, a small increase in the output voltage can trigger the voltage control loop 20 to operate, further helping to accelerate the sending of a signal to the voltage conversion unit 102 to stop outputting power (i.e., prevent the voltage V1 from continuing to increase).

[0115] The charging control method further includes delaying for a preset time after a change in the output voltage and / or output current satisfies a preset condition, and restoring the value at the second input terminal of the voltage control loop 20 and / or the value at the first input terminal of the current control loop 30 after the preset delay. This configuration ensures a smooth recovery of the output voltage.

[0116] The change in output voltage meeting the preset condition indicates that the increase in output voltage is greater than a first set value, and the change in output current meeting the preset condition indicates that the decrease in output current is greater than a second set value.

[0117] In one embodiment, after the preset delay time, the value at the second input terminal of the voltage control loop 20 is restored, that is, the low-level voltage control signal V-Pulse is removed.

[0118] In one embodiment, after a predetermined delay time, the value at the second input terminal of the voltage control loop 20 is restored, that is, the reference voltage V-Ctrl of the voltage control loop 20 is restored.

[0119] In one embodiment, restoring the value at the second input terminal of the voltage control loop 20 after the preset delay time means removing the low-level voltage control signal V-Pulse and restoring the reference voltage V-Ctrl of the voltage control loop 20 .

[0120] In one embodiment, after the preset delay time, the value at the first input terminal of the current control loop 30 is restored, that is, the high-level current control signal I-Pulse is removed.

[0121] The charging control method further includes delaying for a preset time after a change in the output voltage and / or output current satisfies a preset condition, and after the preset delay, restoring the value at the second input terminal of the voltage control loop 20 and / or the value at the first input terminal of the current control loop 30, and also restoring the reference current I-Ctrl of the current control loop 30. This configuration ensures a smooth recovery of the output voltage.

[0122] The change of the output voltage meeting the preset condition and the change of the output current meeting the preset condition are the same as those described above and will not be repeated here.

[0123] In one embodiment, the value at the second input terminal of the voltage control loop 20 is restored after a preset delay time, and the reference current I-Ctrl of the current control loop 30 is also restored (i.e., the low-level voltage control signal V-Pulse is removed, and the reference current I-Ctrl of the current control loop 30 is restored).

[0124] In one embodiment, the value at the second input terminal of the voltage control loop 20 is restored after a preset delay time, and the reference current I-Ctrl of the current control loop 30 is also restored (i.e., the reference voltage V-Ctrl of the voltage control loop 20 and the reference current I-Ctrl of the current control loop 30 are restored).

[0125] In one embodiment, the value at the second input terminal of the voltage control loop 20 is restored after a preset delay time, and the reference current I-Ctrl of the current control loop 30 is also restored (i.e., the low-level voltage control signal V-Pulse is removed, and the reference voltage V-Ctrl of the voltage control loop 20 and the reference current I-Ctrl of the current control loop 30 are restored).

[0126] In one embodiment, the value at the first input terminal of the current control loop 30 is restored after a preset delay time, and the reference current I-Ctrl of the current control loop 30 is also restored (i.e., the high-level current control signal I-Pulse is removed, and the reference current I-Ctrl of the current control loop 30 is also restored).

[0127] In one embodiment, after the output voltage and / or output current changes meet preset conditions, a preset delay is applied. After the preset delay, the current control signal I-Pulse and the voltage control signal V-Pulse are sequentially removed, and the reference voltage V-Ctrl and reference current I-Ctrl are synchronously restored, allowing the charging control circuit to resume normal operation. This sequential order ensures that the voltage control loop remains active after protection, thereby better ensuring a smooth recovery of the output voltage.

[0128] In order to verify the practical effect of the embodiment of the present invention, the following experiments were conducted:

[0129] Experimental conditions: Set the current control loop reference current to approximately 4A in constant current mode. Set the voltage control loop reference voltage to approximately 70V in constant voltage mode. Allow the device to stabilize in constant voltage mode at approximately 70V after hot-swap removal. Connect a 48V load for testing. Connect an oscilloscope probe to the output electrolytic capacitor to evaluate changes in output voltage after hot-swap removal.

[0130] Figure 7 This is a measurement diagram of the output voltage waveform during the hot plug and unplug process of the charging control circuit in related technology. Figure 7 The left section shows the output voltage in stable constant current mode, around 48V, while the right section shows the output voltage in constant voltage mode, around 70V. The sharp voltage rise in the middle indicates that the device was unplugged, resulting in a large spike (approximately 18V higher than the constant voltage level), and a long time to return to the constant voltage state (over 2 seconds).

[0131] Figure 8 This is a measurement diagram of the output voltage waveform during the hot plug and unplug process of the charging control circuit provided by an embodiment of the present invention. Figure 8The left section also shows the output voltage in a stable constant current mode, which is about 48V. The right section also shows the output voltage in a constant voltage mode of about 70V. There is a short drop effect in the middle of the voltage rise, which is a manifestation of the charging control method provided by the embodiment of the present invention. When the output voltage continues to recover and rises to a constant voltage mode close to 70V, the waveform is smooth without spikes. And it takes only a short time from hot unplugging to restoring a stable constant voltage state (the intermediate process is about 0.1 seconds). The above comparative test results verify the effectiveness of the embodiment of the present invention.

[0132] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A charging control circuit, characterized in that: include: Output module, voltage control loop, current control loop and control module; The control module is coupled to the output module and configured to receive the output current and output voltage of the output module; The voltage control loop has a first input terminal, a second input terminal and an output terminal, wherein the first input terminal is used to receive the power supply voltage of the output module, and the second input terminal is coupled to the first output pin of the control module, and the control module is configured to provide a reference voltage to the second input terminal of the voltage control loop; The current control loop has a first input terminal, a second input terminal and an output terminal, wherein the first input terminal is coupled to the second output pin of the control module, and the second input terminal is coupled to the third output pin of the control module, and the control module is configured to provide a value representing the output current to the first input terminal of the current control loop, and provide a reference current to the second input terminal of the current control loop; The control module is configured to lower the value at the second input terminal of the voltage control loop and / or raise the value at the first input terminal of the current control loop.

2. The charging control circuit according to claim 1, wherein: The voltage control loop includes a first operational amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor and a second capacitor; The first end of the first resistor is used to receive the power supply voltage of the output module, and the second end of the first resistor is connected to the first end of the second resistor and the first end of the third resistor; The second end of the second resistor is connected to the first input end of the first operational amplifier, and the second end of the third resistor is grounded; A first end of the fourth resistor is connected to the first output pin of the control module, a second end of the fourth resistor is connected to the second input end of the first operational amplifier and the first end of the first capacitor, and a second end of the first capacitor is grounded; The first end of the second capacitor is connected to the first input end of the first operational amplifier, the second end of the second capacitor is connected to the first end of the fifth resistor, and the second end of the fifth resistor is connected to the output end of the first operational amplifier.

3. The charging control circuit according to claim 1, wherein: The current control loop includes a second operational amplifier, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a third capacitor and a fourth capacitor; A first end of the sixth resistor is connected to the first input end of the second operational amplifier, a second end of the sixth resistor is connected to the first end of the seventh resistor, and a second end of the seventh resistor is connected to the second output pin of the control module; A first end of the eighth resistor is connected to the third output pin of the control module, a second end of the eighth resistor is connected to the second input end of the second operational amplifier and the first end of the third capacitor, and a second end of the third capacitor is grounded; The first end of the fourth capacitor is connected to the first input end of the second operational amplifier, the second end of the fourth capacitor is connected to the first end of the ninth resistor, and the second end of the ninth resistor is connected to the output end of the second operational amplifier.

4. The charging control circuit according to claim 1, wherein: The control module further has a fourth output pin, which is coupled to the second input terminal of the voltage control loop. The control module is used to provide a low-level voltage control signal to the second input terminal of the voltage control loop and / or pull down the reference voltage.

5. The charging control circuit according to claim 1 or 4, characterized in that: The control module further has a fifth output pin, which is coupled to the first input terminal of the current control loop. The control module is used to provide a high-level current control signal to the first input terminal of the current control loop.

6. The charging control circuit according to claim 1, wherein: The control module is further configured to lower the reference current.

7. The charging control circuit according to claim 1, wherein: The output module includes a switch circuit and a voltage conversion unit; The voltage conversion unit is coupled to the output ends of the voltage control loop and the current control loop, and is further coupled to the switch circuit.

8. The charging control circuit according to claim 1, wherein: The control module is further configured to adjust a reference voltage at a second input terminal of the voltage control loop to be greater than the output voltage, and to adjust a difference between the reference voltage and the output voltage to be a preset value.

9. A charging control method, characterized in that: Applied to the charging control circuit according to any one of claims 1 to 8, the charging control method comprises: Collecting the output voltage and output current of the output module and controlling the constant current output of the output module through a current control loop or controlling the constant voltage output of the output module through a voltage control loop; If the change of the output voltage and / or the output current meets the preset conditions, the value at the second input terminal of the voltage control loop is lowered and / or the value at the first input terminal of the current control loop is increased to control the output module to stop working.

10. The charging control method according to claim 9, characterized in that: The preset conditions include that within a set time, the output voltage rises by more than a first set value, and / or, within a set time, the output current falls by more than a second set value; The step of lowering the value at the second input terminal of the voltage control loop comprises: providing a low-level voltage control signal to the second input terminal of the voltage control loop and / or lowering the reference voltage; The step of increasing the value at the first input terminal of the current control loop includes providing a high-level current control signal to the first input terminal of the current control loop.

11. The charging control method according to claim 10, wherein: The charging control method further includes: If the output voltage rises by more than a first set value within a set time, and / or the output current drops by more than a second set value within a set time, the reference current of the current control loop is lowered.

12. The charging control method according to claim 9, wherein: The charging control method further includes: When the change of the output voltage and / or the output current does not meet the preset condition, the reference voltage of the second input terminal of the voltage control loop is controlled to be greater than the output voltage, and the difference between the reference voltage and the output voltage is controlled to be a preset value.

13. The charging control method according to claim 9, wherein: The charging control method further includes: After the change of the output voltage and / or the output current meets the preset condition, a preset time is delayed, and after the preset time, the value at the second input end of the voltage control loop and / or the value at the first input end of the current control loop are restored.

14. The charging control method according to claim 11, wherein: The charging control method further includes: After the change of the output voltage and / or the output current meets the preset conditions, a preset time is delayed, and after the preset time is delayed, the value at the second input terminal of the voltage control loop and / or the value at the first input terminal of the current control loop is restored, and the reference current of the current control loop is also restored.

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