CN-224233342-U - Charging protection circuit

CN224233342UCN 224233342 UCN224233342 UCN 224233342UCN-224233342-U

Abstract

The application relates to a charging protection circuit which comprises an on-off control circuit and an adjusting circuit, wherein the on-off control circuit is connected with a charging power supply and is used for disconnecting a circuit for charging a battery by the charging power supply under the condition of receiving a disconnection control signal, and the adjusting circuit is connected with the on-off control circuit and is used for reducing the amplitude of the charging signal provided by the on-off control circuit to the battery before the disconnection 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.

Inventors

LUO MAOFENG
GAO SONG
LUO WANG
ZHANG BAOYU
ZHANG XIANWEI

Assignees

昆山联滔电子有限公司

Dates

Publication Date: 20260512
Application Date: 20250421

Claims (11)

1. A charge protection circuit connected between a battery and a charging source, the charge protection circuit comprising: The on-off control circuit is connected with the charging power supply and the battery, and cuts off a loop for charging the battery by the charging power supply under the condition of receiving a cut-off control signal; And the adjusting circuit is connected with the on-off control circuit and used for adjusting down the amplitude of a charging signal provided to the battery by the on-off control circuit before the off control signal is generated.
2. The charge protection circuit of claim 1, wherein the conditioning circuit comprises: The adjusting loop is connected with the on-off control circuit, and the amplitude of the charging signal provided to the battery by the on-off control circuit is reduced under the condition that the adjusting control signal is received; And the controller is connected with the on-off control circuit and the regulating loop and generates the regulating control signal before generating the disconnection control signal.
3. The charge protection circuit of claim 2, further comprising: An AC/DC power converter for converting the electric power supplied by the charging power supply into a direct current electric signal; And the output voltage detection circuit is connected with the AC/DC power converter and the controller, and generates a first indication signal for indicating the controller to generate the disconnection control signal after detecting that the amplitude of the charging signal is reduced.
4. The charge protection circuit of claim 3, further comprising: And the output current detection circuit is connected with the AC/DC power converter and the controller, and generates a second indication signal for indicating the controller to generate the disconnection control signal after detecting that the amplitude of the charging signal is reduced.
5. The charge protection circuit of claim 2, wherein the controller comprises: The digital-to-analog converter is connected with the regulating loop and generates positive feedback reference voltage or negative feedback reference voltage, and the positive feedback reference voltage or the negative feedback reference voltage regulates down the amplitude of a charging signal provided by the on-off control circuit to the battery.
6. The charge protection circuit of claim 5, wherein the controller comprises: And the pulse width modulator is connected with the regulating loop and generates positive feedback reference voltage or negative feedback reference voltage, and the positive feedback reference voltage or the negative feedback reference voltage regulates down the amplitude of a charging signal provided by the on-off control circuit to the battery.
7. The charge protection circuit of claim 6, further comprising: And the filter circuit is connected with the digital-to-analog converter and the regulating loop or connected with the pulse width modulator and the regulating loop and is used for providing the positive feedback reference voltage after the filtering process or the negative feedback reference voltage after the filtering process for the regulating loop.
8. The charge protection circuit according to any one of claims 2 to 6, wherein the on-off control circuit includes: The output switch device is connected with the first direct-current power supply at a first end, is used as a positive output end of the charger, is connected with the output end of the regulating loop and is used as a negative output end of the charger, and is connected with the output end of the regulating loop at a third end; the first end of the control switch device is connected with the second end and the control end of the output switch device, and the second end of the control switch device is connected with a third direct current power supply; And the first end of the voltage conversion circuit is connected with the control end of the control switch device, the second end of the voltage conversion circuit is grounded, and the control end receives the disconnection control signal.
9. The charge protection circuit of claim 8, wherein the output switching device comprises: the first end of the first switch tube is connected with the first direct-current power supply; And the first end of the second switching tube is connected with the second end of the first switching tube, the second end of the second switching tube is connected with the second direct-current power supply and is used as the positive output end of the charger, and the control end of the second switching tube is connected with the first end of the control switching device and is connected with the control end of the first switching tube.
10. The charge protection circuit of claim 9, wherein the control switching device comprises: And the first end of the third switching tube is connected with the control end of the second switching tube and is connected with the first end of the second switching tube through a first voltage dividing resistor, the second end of the third switching tube is connected with a third direct current power supply through a first current limiting resistor, and the control end of the third switching tube is connected with the first end of the voltage conversion circuit through a second current limiting resistor.
11. The charge protection circuit of claim 10, wherein the voltage conversion circuit comprises: And the first end of the fourth switching tube is connected with the control end of the third switching tube through the second current limiting resistor, the second end of the fourth switching tube is grounded, and the control end of the fourth switching tube is connected with the disconnection control signal through the third current limiting resistor.

Description

Charging protection circuit Technical Field The application relates to the technical field of power electronics, in particular to a charging protection circuit. Background As an important tool for modern city travel, the battery life of electric vehicles has been the focus of attention of users. The correct charging method can prolong the service life of the battery and ensure the stable performance of the electric vehicle. However, in the conventional technology, when the output of the charging power supply of the electric vehicle needs to be turned off in a normal charging state, a method of directly turning off an output switching device is generally adopted to stop charging, so that surge spike voltage is easily generated in the charging power supply, larger stress is brought to an internal circuit of the charging power supply, even the charging power supply is subjected to overvoltage protection and shutdown or device damage, and the working performance and reliability of the charging power supply are seriously reduced. Disclosure of utility model Based on this, it is necessary to provide a charging protection circuit for solving the above-mentioned problems in the prior art, by continuously adjusting the output electric signal amplitude of the charging power supply to reduce, and then disconnecting the circuit for charging the battery from the charging power supply, the surge peak voltage and the charging stress are obviously reduced or avoided, and the performance and the reliability of the charging power supply are improved. The first aspect of the application provides a charging protection circuit connected between a battery and a charging power supply, comprising an on-off control circuit and a regulating circuit, wherein the on-off control circuit is used for being connected with the charging power supply and the battery and is used for disconnecting a loop of the charging power supply for charging the battery under the condition that a disconnection control signal is received, and the regulating circuit is connected with the on-off control circuit and is used for regulating the amplitude of the charging signal provided to the battery by the on-off control circuit before the disconnection control signal is generated. According to the charging protection circuit in the embodiment, before the adjusting circuit generates the disconnection control signal for controlling the on-off control circuit to disconnect the charging power supply from the charging circuit of the battery, the amplitude of the charging signal provided by the charging power supply to the battery through the on-off control circuit is reduced, surge peak voltage and charging stress are obviously reduced or avoided, overvoltage protection halt or device damage event of the charging power supply is avoided, and the working performance and reliability of the charging power supply are improved. In some embodiments, the regulating circuit comprises a regulating loop and a controller, wherein the regulating loop is connected with the on-off control circuit and used for regulating down the amplitude of a charging signal provided by the charging power supply to the battery through the on-off control circuit under the condition that the regulating control signal is received, and the controller is connected with the on-off control circuit and the regulating loop and used for generating the regulating control signal before generating the disconnection control signal. The controller generates an adjustment control signal prior to generating the off control signal such that the adjustment loop adjusts the magnitude of a charge signal provided by the on-off control circuit to the battery. In some embodiments, the charging protection circuit further comprises an AC/DC power converter and an output current detection circuit, the AC/DC power converter is used for converting electric energy provided by the charging power supply into a direct current signal, and the output voltage detection circuit is connected with the charging power supply and the controller and is used for generating a first indication signal for indicating the controller to generate a disconnection control signal after detecting that the amplitude of the charging signal is reduced. In some embodiments, the charging protection circuit further comprises an output current detection circuit, wherein the output current detection circuit is connected with the AC/DC power converter and the controller and is used for generating a second indication signal for indicating the controller to generate a disconnection control signal after detecting that the amplitude of the charging signal is reduced. Thus, surge peak voltage and charging stress can be obviously reduced or avoided. In some embodiments, the controller includes a digital-to-analog converter coupled to the regulation loop for generating a positive feedback reference voltage or a negative feedback reference voltage for regulating th