Electric vehicle protection circuit

Abstract

The utility model discloses an electric vehicle protection circuit, comprising a detection and output circuit, the input end of which is connected with a charger, and the output end of which is connected with the input end of a first switching circuit, the input end of a charging circuit, the input end of a driving circuit and a brake circuit of an electric vehicle; the output end of the first switching circuit is connected with the input end of the second switching circuit; the output end of the driving circuit is connected with the charging circuit; the output end of the second switching circuit is connected with the charging circuit; and the output end of the charging circuit is connected with the battery. In the discharging state, the temperature information of the battery is effectively detected through the detection and output circuit, and the brake signal is output to the brake circuit of the electric vehicle; and the temperature information of the battery is detected in the charging state, and charging of the battery is stopped, so that battery deformation is effectively avoided, the service life of the battery is prolonged, and potential safety hazards are also avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of electric vehicle protection, in particular to an electric vehicle protection circuit. Background Art

[0002] Electric bicycles have a high usage rate and popularity in my country. Electric bicycles have improved the convenience of travel and have become an indispensable partner for people in work and life. The current batteries of electric bicycles are usually lead-acid batteries. The main advantages of lead-acid batteries are that they are relatively cheap and have a certain mileage. However, due to the characteristics of lead-acid batteries that are easy to heat up, they will cause serious water loss in the battery. Without additional protective measures, on the one hand, it will cause battery deformation and shorten the battery life; on the other hand, when charging and discharging are abnormal and not protected, it will cause certain safety hazards. Utility Model Content

[0003] Based on this, it is necessary to propose an electric vehicle protection circuit to address the above problems.

[0004] An electric vehicle protection circuit, comprising:

[0005] A detection and output circuit, the input end of which is connected to the charger, and the output end of which is connected to the input end of the first switch circuit, the input end of the charging circuit, the input end of the drive circuit and the brake circuit of the electric vehicle; used to detect the temperature information of the battery and receive the connection signal of the charger, and output a switch signal to the charging circuit and the drive circuit, and output a control signal to the first switch circuit; and receive the temperature information and output a brake signal to the brake circuit;

[0006] The output end of the first switch circuit is connected to the input end of the second switch circuit, and is used to receive the control signal, and to turn on or off the loop between the detection and output circuit and the second switch circuit, and to output the control signal to the drive circuit;

[0007] The driving circuit, an output end of which is connected to the charging circuit, is used to receive the switch signal and output a square wave signal to the charging circuit;

[0008] The second switch circuit, whose output end is connected to the charging circuit, is used to receive the control signal and output a charging signal to the charging circuit;

[0009] The charging circuit has an output end connected to the battery and is used to receive the switch signal, the square wave signal and the charging signal, and to store electric energy and charge the battery.

[0010] In one embodiment, the charging circuit comprises:

[0011] a power supply circuit, whose input end is connected to the battery, and whose output end is connected to the detection and output circuit, the first switch circuit, the drive circuit and the second switch circuit, and is used to supply power to the detection and output circuit, the first switch circuit, the drive circuit and the second switch circuit;

[0012] The second switch circuit has an input end connected to the output end of the detection and output circuit, and an output end connected to the energy storage circuit, and is used to receive the switch signal and turn on or off the loop between the charger and the energy storage circuit;

[0013] a third switch circuit, whose input end is connected to the output end of the second switch circuit and whose output end is connected to the battery, and is used to receive the charging signal and turn on or off the circuit between the second switch circuit and the battery;

[0014] The energy storage circuit is used for storing energy.

[0015] In one embodiment, the detection and output circuit includes: a first comparator, a first diode, a first resistor, a second diode, a third diode and a thermistor;

[0016] The first input terminal of the first comparator is connected to one end of the first resistor, the other end of the first resistor is connected to the anode of the first diode, and the cathode of the first diode is connected to the charger;

[0017] The second input terminal of the first comparator is connected to one end of the thermistor, and the thermistor is placed on the battery;

[0018] The first output terminal of the first comparator is connected to the input terminal of the first switch circuit, the input terminal of the charging circuit and the input terminal of the driving circuit;

[0019] The second output terminal of the first comparator is connected to the cathode of the second diode, and the anode of the second diode is connected to the brake circuit.

[0020] In one embodiment, the first switch circuit includes: a fourth diode, a first transistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor;

[0021] One end of the third resistor is connected to the second output end of the first comparator, and the other end is connected to one end of the fourth resistor and the base of the first transistor;

[0022] The other end of the fourth resistor is connected to the emitter of the first transistor and is grounded;

[0023] The collector of the first transistor is connected to the cathode of the fourth diode and the input end of the second switch circuit;

[0024] An anode of the fourth diode is connected to one end of the fifth resistor, the other end of the fifth resistor is connected to one end of the second resistor, and the other end of the second resistor is connected to the second output end of the first comparator.

[0025] In one embodiment, the driving circuit includes: a second comparator, a second triode, a third triode, a sixteenth resistor, a fourth triode and a fourth diode;

[0026] The power supply terminal of the second comparator is connected to the collector of the third transistor;

[0027] The emitter of the third triode is connected to the power supply, the base of the third triode is connected to one end of the sixteenth resistor, and the other end of the sixteenth resistor is connected to the collector of the second triode;

[0028] The base of the second transistor is connected to the output end of the detection and output circuit, and the emitter of the second transistor is grounded;

[0029] The base of the fourth transistor is connected to the output end of the second comparator, the collector of the fourth transistor is connected to the charging circuit, and the emitter of the fourth transistor is grounded;

[0030] An anode of the fourth transistor is connected to the output end of the second comparator, and a cathode of the fourth transistor is connected to the charging circuit.

[0031] In one embodiment, the second switch circuit includes: a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor and an eleventh resistor;

[0032] The emitter of the fifth transistor is connected to the output end of the first switch circuit, the collector of the fifth transistor is connected to one end of the sixth resistor, and the base of the fifth transistor is connected to the base of the sixth transistor;

[0033] The emitter of the sixth transistor is connected to the output end of the first switch circuit, and the collector of the sixth transistor is connected to one end of the seventh resistor;

[0034] The other end of the sixth resistor is connected to the base of the eighth transistor; the collector of the eighth transistor is connected to one end of the tenth resistor, and the other end of the tenth resistor is connected to the battery;

[0035] The other end of the seventh resistor is connected to the base of the seventh transistor; the collector of the seventh transistor is connected to one end of the eleventh resistor, and the other end of the eleventh resistor is connected to the battery;

[0036] One end of the eighth resistor is connected to the base of the sixth transistor, and the other end is connected to the power supply;

[0037] One end of the ninth resistor is connected to the base of the sixth transistor, and the other end is grounded.

[0038] In one embodiment, the second switch circuit includes: a ninth transistor, a tenth transistor and a fifth diode;

[0039] The base of the triode is connected to the battery, the emitter of the triode is connected to the base of the ninth triode, and the collector of the triode is connected to the detection and output circuit;

[0040] The emitter of the ninth triode is grounded, and the collector of the ninth triode is connected to the detection and output circuit;

[0041] An anode of the fifth diode is grounded, and a cathode of the fifth diode is connected to the output circuit.

[0042] In one embodiment, the third switch circuit comprises: a fourteenth transistor, a first MOS transistor and a twelfth resistor;

[0043] The emitter of the fourteenth triode is connected to the battery and grounded, the collector of the fourteenth triode is connected to one end of the twelfth resistor, and the other end of the twelfth resistor is connected to the gate of the first MOS tube;

[0044] The source of the first MOS tube is connected to the battery, and the drain of the first MOS tube is connected to the output end of the second switch circuit.

[0045] In one embodiment, the charging circuit further includes a fourth switch circuit, and the fourth switch circuit includes: a second MOS transistor, a third MOS transistor and a sixth diode;

[0046] The drain of the second MOS tube is connected to the charger, the gate of the second MOS tube is connected to the output end of the second switch circuit, and the source connected to the output end of the second switch circuit is connected to the source of the third MOS tube;

[0047] The gate of the third MOS tube is connected to the gate of the second MOS tube, and the drain of the third MOS tube is connected to the battery;

[0048] An anode of the sixth diode is connected to the source of the second MOS transistor, and a cathode of the sixth diode is connected to the gate of the second MOS transistor.

[0049] In one embodiment, the energy storage circuit includes: a seventh diode and a first capacitor;

[0050] An anode of the seventh diode is connected to the drain of the first MOS transistor, and a cathode of the seventh diode is connected to one end of the first capacitor and an output end of the second switch circuit;

[0051] The other end of the first capacitor is connected to the output end of the detection and output circuit.

[0052] Implementing the embodiments of the present utility model will have the following beneficial effects:

[0053] The present application detects and outputs the temperature information of the battery and the connection signal of the charger, and outputs a switch signal to the charging circuit and the driving circuit, and outputs a control signal to the first switch circuit; and receives the temperature information and outputs a brake signal to the brake circuit; the first switch circuit receives the control signal, and turns on or off the loop between the detection and output circuit and the second switch circuit, and outputs the control signal to the drive circuit; the drive circuit receives the switch signal and outputs a square wave signal to the charging circuit; the second switch circuit receives the control signal and outputs a charging signal to the charging circuit; the charging circuit receives the switch signal, the square wave signal and the charging signal, and stores electric energy and charges the battery. The present application effectively avoids battery deformation, prolongs the battery life, and avoids the occurrence of safety hazards by using the detection and output circuit to effectively detect the temperature information of the battery in the discharge state, and outputs a brake signal to the brake circuit of the electric vehicle; and detects the temperature information of the battery in the charging state, and stops charging the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0055] in:

[0056] Figure 1 A structural block diagram of an electric vehicle protection circuit in one embodiment;

[0057] Figure 2is a circuit diagram of a detection and output circuit and a first switch circuit in one embodiment;

[0058] Figure 3 is a circuit diagram of a charging circuit in one embodiment;

[0059] Figure 4 is a circuit diagram of a driving circuit in one embodiment;

[0060] Figure 5 FIG. 4 is a circuit diagram of a second switch circuit in an embodiment. DETAILED DESCRIPTION

[0061] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0062] Electric bicycles have a high usage rate and popularity in my country. Electric bicycles have improved the convenience of travel and have become an indispensable partner in people's work and life. The batteries of current electric bicycles are usually lead-acid batteries. The main advantages of lead-acid batteries are that they are relatively cheap and have a certain mileage. However, due to the characteristics of lead-acid batteries that are easy to heat up, they will cause serious water loss in the batteries. Without additional protection measures, on the one hand, it will cause battery deformation and shorten the battery life; on the other hand, if the charging and discharging are abnormal and not protected, it will cause certain safety hazards. In order to solve the above technical problems, the present application provides an electric vehicle protection circuit, such as Figure 1As shown, it includes: a detection and output circuit 10, a first switch circuit 20, a charging circuit 30, a drive circuit 40 and a second switch circuit 50, wherein the input end of the detection and output circuit 10 is connected to the charger, and the output end is connected to the input end of the first switch circuit 20, the input end of the charging circuit 30, the input end of the drive circuit 40 and the brake circuit of the electric vehicle; it is used to detect the temperature information of the battery and receive the connection signal of the charger, and output the switch signal to the charging circuit 30 and the drive circuit 40, and output the control signal to the first switch circuit 20; and receive the temperature information and output the brake signal to the brake circuit; the output end of the first switch circuit 20 is connected to the second switch circuit 50 The input end of the detection and output circuit 10 is connected to receive the control signal, and the loop between the detection and output circuit 10 and the second switch circuit 50 is turned on or off, and the control signal is output to the drive circuit 40; the output end of the drive circuit 40 is connected to the charging circuit 30, and is used to receive the switch signal and output a square wave signal to the charging circuit 30; the output end of the second switch circuit 50 is connected to the charging circuit 30, and is used to receive the control signal and output a charging signal to the charging circuit 30; the output end of the charging circuit 30 is connected to the battery, and is used to receive the switch signal, the square wave signal and the charging signal, and store electric energy and charge the battery.

[0063] The present application utilizes a detection and output circuit to effectively detect the temperature information of the battery in the discharge state and output a brake signal to the brake circuit of the electric vehicle; and detects the temperature information of the battery in the charging state and stops charging the battery, thereby effectively avoiding battery deformation, extending the battery life, and avoiding the occurrence of safety hazards.

[0064] When the charger fully charges the battery and the plug is unplugged, the voltage of the charging socket is generally high voltage greater than 42V, which exceeds the safe voltage for the human body. Touching it at this time may cause certain safety injuries. After adding the electric vehicle protection circuit of the present application, the entire vehicle is fully charged and the charger is unplugged. The voltage of the charging socket is 0V, so there is no danger even if it is touched.

[0065] During the charging process, if the battery heats up or thermal runaway occurs, and the detection and output circuit monitors that the battery temperature exceeds 65°C abnormally, the first switch circuit can disconnect the charging circuit and stop charging the battery to ensure that the battery temperature does not continue to rise. When the battery temperature drops to normal temperature, the first switch circuit will restore the circuit normally and allow the charger to continue charging the battery.

[0066] During the discharge process, the battery will also generate heat when it is discharged. When the detection and output circuit detects that the battery temperature is too high and reaches 65°C, the electric vehicle protection circuit will trigger the brake function in time, making the whole vehicle unable to ride, that is, preventing the battery from continuing to discharge. When the battery temperature drops to normal temperature, the electric vehicle protection circuit will normally release the brake function and allow the battery to continue to discharge and use. The main purpose of the electric vehicle protection circuit is to solve the problem of abnormal battery temperature when the electric vehicle is discharged during riding and when the charger is charging, and to provide timely protection to prevent safety accidents.

[0067] In one embodiment, Figure 3 As shown, the charging circuit 30 includes: a power supply circuit, a second switch circuit 301, a third switch circuit 302 and an energy storage circuit 304, wherein the input end of the power supply circuit is connected to the battery, and the output end is connected to the detection and output circuit 10, the first switch circuit 20, the drive circuit 40 and the second switch circuit 50, and is used to supply power to the detection and output circuit 10, the first switch circuit 20, the drive circuit 40 and the second switch circuit 50; the input end of the second switch circuit 301 is connected to the output end of the detection and output circuit 10, and the output end is connected to the energy storage circuit 304, and is used to receive the switching signal and turn on or off the loop between the charger and the energy storage circuit 304; the input end of the third switch circuit 302 is connected to the output end of the second switch circuit 50, and the output end is connected to the battery, and is used to receive the charging signal and turn on or off the loop between the second switch circuit 50 and the battery; the energy storage circuit 304 is used to store energy.

[0068] In one embodiment, Figure 2 As shown, the detection and output circuit 10 includes: a first comparator U2, a first diode D11, a first resistor R42, a second diode D9, a third diode D10 and a thermistor RT1; wherein, the first input terminal INA- of the first comparator U2 is connected to one end of the first resistor R42, the other end of the first resistor R42 is connected to the anode of the first diode D11, and the cathode of the first diode D11 is connected to the charger; the second input terminal INB- of the first comparator U2 is connected to one end of the thermistor RT1, and the thermistor RT1 is placed on the battery; the first output terminal OUTA of the first comparator U2 is connected to the input end of the first switch circuit 20, the input end of the charging circuit 30 and the input end of the driving circuit 40; the second output terminal OUTB of the first comparator U2 is connected to the cathode of the second diode D9, and the anode of the second diode D9 is connected to the brake circuit.

[0069] In one embodiment, Figure 2 As shown, the first switch circuit 20 includes: a fourth diode D5, a first transistor Q4, a second resistor R28, a third resistor R25, a fourth resistor R7 and a fifth resistor R26; wherein one end of the third resistor R25 is connected to the second output terminal OUTB of the first comparator U2, and the other end is connected to one end of the fourth resistor R7 and the base of the first transistor Q4; the other end of the fourth resistor R7 is connected to the emitter of the first transistor Q4 and grounded; the collector of the first transistor Q4 is connected to the cathode of the fourth diode D5 and the input end of the second switch circuit 50; the anode of the fourth diode D5 is connected to one end of the fifth resistor R26, the other end of the fifth resistor R26 is connected to one end of the second resistor R28, and the other end of the second resistor R28 is connected to the second output terminal OUTB of the first comparator U2.

[0070] In one embodiment, Figure 4 As shown, the driving circuit 40 includes: a second comparator U1, a second triode Q14, a third triode Q13, a sixteenth resistor R29, a fourth triode Q9 and a fourth diode D8; wherein the power supply terminal VCC of the second comparator U1 is connected to the collector of the third triode Q13; the emitter of the third triode Q13 is connected to the power supply, the base of the third triode Q13 is connected to one end of the sixteenth resistor R29, and the other end of the sixteenth resistor R29 is connected to the collector of the second triode Q14. The base of the second transistor Q14 is connected to the output end of the detection and output circuit 10, and the emitter of the second transistor Q14 is grounded; the base of the fourth transistor Q9 is connected to the output end OUTB of the second comparator U1, the collector of the fourth transistor Q9 is connected to the charging circuit 30, and the emitter of the fourth transistor Q9 is grounded; the anode of the fourth transistor Q9 is connected to the output end OUTB of the second comparator U1, and the cathode of the fourth transistor Q9 is connected to the charging circuit 30.

[0071] In one embodiment, Figure 5As shown, the second switch circuit 50 includes: a fifth transistor Q11, a sixth transistor Q12, a seventh transistor Q10, an eighth transistor Q7, a sixth resistor R31, a seventh resistor R32, an eighth resistor R21, a ninth resistor R22, a tenth resistor R2 and an eleventh resistor R39; wherein the emitter of the fifth transistor Q11 is connected to the output end of the first switch circuit 20, the collector of the fifth transistor Q11 is connected to one end of the sixth resistor R31, and the base of the fifth transistor Q11 is connected to the base of the sixth transistor Q12; the emitter of the sixth transistor Q12 is connected to the output end of the first switch circuit 20, and the collector of the sixth transistor Q12 is connected to the seventh One end of the resistor R32 is connected; the other end of the sixth resistor R31 is connected to the base of the eighth transistor Q7; the collector of the eighth transistor Q7 is connected to one end of the tenth resistor R2, and the other end of the tenth resistor R2 is connected to the battery; the other end of the seventh resistor R32 is connected to the base of the seventh transistor Q10; the collector of the seventh transistor Q10 is connected to one end of the eleventh resistor R39, and the other end of the eleventh resistor R39 is connected to the battery; one end of the eighth resistor R21 is connected to the base of the sixth transistor Q12, and the other end is connected to the power supply; one end of the ninth resistor R22 is connected to the base of the sixth transistor Q12, and the other end is grounded.

[0072] In one embodiment, Figure 3 As shown, the second switch circuit 301 includes: a ninth triode Q2, a tenth triode Q3 and a fifth diode D3; wherein the base of the tenth triode Q3 is connected to the battery, the emitter of the tenth triode Q3 is connected to the base of the ninth triode Q2, and the collector of the tenth triode Q3 is connected to the detection and output circuit 10; the emitter of the ninth triode Q2 is grounded, and the collector of the ninth triode Q2 is connected to the detection and output circuit 10; the anode of the fifth diode D3 is grounded, and the cathode of the fifth diode D3 is connected to the output circuit 10.

[0073] In one embodiment, the third switch circuit 302 includes: a fourteenth transistor Q1, a first MOS transistor Q8 and a twelfth resistor R1; wherein the emitter of the fourteenth transistor Q1 is connected to the battery and grounded, the collector of the fourteenth transistor Q1 is connected to one end of the twelfth resistor R1, and the other end of the twelfth resistor R1 is connected to the gate of the first MOS transistor Q8; the source of the first MOS transistor Q8 is connected to the battery, and the drain of the first MOS transistor Q8 is connected to the output end of the second switch circuit 50.

[0074] In one embodiment, Figure 3 As shown, the charging circuit 30 further includes a fourth switch circuit 303, and the fourth switch circuit 303 includes: a second MOS transistor Q5, a third MOS transistor Q6 and a sixth diode D1; the drain of the second MOS transistor Q5 is connected to the charger, the gate of the second MOS transistor Q5 is connected to the output end of the second switch circuit 50, and the source connected to the output end of the second switch circuit 50 is connected to the source of the third MOS transistor Q6; the gate of the third MOS transistor Q6 is connected to the gate of the second MOS transistor Q5, and the drain of the third MOS transistor Q6 is connected to the battery; the anode of the sixth diode D1 is connected to the source of the second MOS transistor Q5, and the cathode of the sixth diode D1 is connected to the gate of the second MOS transistor Q5.

[0075] In one embodiment, Figure 3 As shown, the energy storage circuit 304 includes: a seventh diode D4 and a first capacitor C6; wherein, the anode of the seventh diode D4 is connected to the drain of the first MOS tube Q8, and the cathode of the seventh diode D4 is connected to one end of the first capacitor C6 and the output end of the second switch circuit 50; the other end of the first capacitor C6 is connected to the output end of the detection and output circuit 10.

[0076] Here’s how this application works:

[0077] like Figure 3 As shown, B+ and B- are the positive and negative terminals of the battery, which are normally charged; C+ and C- are the charger docking terminals, which provide energy for the battery. B+ and B- are normally charged, and a stable 15V voltage is provided to port V12 through the ninth transistor Q2, the tenth transistor Q3 and the fifth diode D3 to power other circuits. Figure 4 As shown, when the switch signal SW output by the detection and output circuit is at a high level, the fourteenth transistor Q1 and the first MOS transistor Q8 are turned on to charge the second capacitor C6, and the voltage of the port VH reaches a voltage higher than B+10V through the eighth diode D7 and the second first capacitor C5. Figure 3 As shown, when the port VG is at a high level, the second MOS tube Q5 and the third MOS tube Q6 conduct C+ to charge B+. When the switch signal SW is at a low point, VH, VG, and C+ have no voltage.

[0078] like Figure 2As shown, port DET is an enable signal for the charger end connected to C+ and C-; low brake is a brake signal for the electronic control connected to the B+ and B- ends. Thermistor RT1 is a temperature sensor, which is mainly installed on the battery (B+ / B-); when port DET is suspended, SW outputs a low level through the first comparator U2; after port DET is connected to the charger, DET will be pulled low, and SW will output a high level through the first comparator U2. When the temperature of thermistor RT1 exceeds 65°, the low brake end signal will be pulled low through the first comparator U2. At this time, the battery is considered abnormal. In the riding state, the whole vehicle will be powered off for protection; in the charging state, the protector will be disconnected and will not replenish power to the battery. Otherwise, it will work normally. When the switch signal SW is at a high level, the second transistor Q14 and the third transistor Q13 are turned on, V12 supplies power to the second comparator U1, and a PWM pulse wave is continuously output through the fourth transistor Q9, which continuously gives Figure 3 The first capacitor C6 is charged. When the port VH is at a high level, VG is at a high level, and the Figure 3 At this time, the second MOS tube Q5 and the third MOS tube Q6 are turned on.

[0079] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope covered by the present invention.

Claims

1. An electric vehicle protection circuit, characterized in that: include: A detection and output circuit, the input end of which is connected to the charger, and the output end of which is connected to the input end of the first switch circuit, the input end of the charging circuit, the input end of the drive circuit and the brake circuit of the electric vehicle; used to detect the temperature information of the battery and receive the connection signal of the charger, and output a switch signal to the charging circuit and the drive circuit, and output a control signal to the first switch circuit; and receive the temperature information and output a brake signal to the brake circuit; The output end of the first switch circuit is connected to the input end of the second switch circuit, and is used to receive the control signal, and to turn on or off the loop between the detection and output circuit and the second switch circuit, and to output the control signal to the drive circuit; The driving circuit, an output end of which is connected to the charging circuit, is used to receive the switch signal and output a square wave signal to the charging circuit; The second switch circuit, whose output end is connected to the charging circuit, is used to receive the control signal and output a charging signal to the charging circuit; The charging circuit has an output end connected to the battery and is used to receive the switch signal, the square wave signal and the charging signal, and to store electric energy and charge the battery.

2. The electric vehicle protection circuit according to claim 1, characterized in that: The charging circuit comprises: a power supply circuit, whose input end is connected to the battery, and whose output end is connected to the detection and output circuit, the first switch circuit, the drive circuit and the second switch circuit, and is used to supply power to the detection and output circuit, the first switch circuit, the drive circuit and the second switch circuit; The second switch circuit has an input end connected to the output end of the detection and output circuit, and an output end connected to the energy storage circuit, and is used to receive the switch signal and turn on or off the loop between the charger and the energy storage circuit; a third switch circuit, whose input end is connected to the output end of the second switch circuit and whose output end is connected to the battery, and is used to receive the charging signal and turn on or off the circuit between the second switch circuit and the battery; The energy storage circuit is used for storing energy.

3. The electric vehicle protection circuit according to claim 1, characterized in that: The detection and output circuit includes: a first comparator, a first diode, a first resistor, a second diode, a third diode and a thermistor; The first input terminal of the first comparator is connected to one end of the first resistor, the other end of the first resistor is connected to the anode of the first diode, and the cathode of the first diode is connected to the charger; The second input terminal of the first comparator is connected to one end of the thermistor, and the thermistor is placed on the battery; The first output terminal of the first comparator is connected to the input terminal of the first switch circuit, the input terminal of the charging circuit and the input terminal of the driving circuit; The second output terminal of the first comparator is connected to the cathode of the second diode, and the anode of the second diode is connected to the brake circuit.

4. The electric vehicle protection circuit according to claim 3, characterized in that: The first switch circuit includes: a fourth diode, a first transistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor; One end of the third resistor is connected to the second output end of the first comparator, and the other end is connected to one end of the fourth resistor and the base of the first transistor; The other end of the fourth resistor is connected to the emitter of the first transistor and is grounded; The collector of the first transistor is connected to the cathode of the fourth diode and the input end of the second switch circuit; An anode of the fourth diode is connected to one end of the fifth resistor, the other end of the fifth resistor is connected to one end of the second resistor, and the other end of the second resistor is connected to the second output end of the first comparator.

5. The electric vehicle protection circuit according to claim 1, characterized in that: The driving circuit comprises: a second comparator, a second triode, a third triode, a sixteenth resistor, a fourth triode and a fourth diode; The power supply terminal of the second comparator is connected to the collector of the third transistor; The emitter of the third triode is connected to the power supply, the base of the third triode is connected to one end of the sixteenth resistor, and the other end of the sixteenth resistor is connected to the collector of the second triode; The base of the second transistor is connected to the output end of the detection and output circuit, and the emitter of the second transistor is grounded; The base of the fourth transistor is connected to the output end of the second comparator, the collector of the fourth transistor is connected to the charging circuit, and the emitter of the fourth transistor is grounded; An anode of the fourth transistor is connected to the output end of the second comparator, and a cathode of the fourth transistor is connected to the charging circuit.

6. The electric vehicle protection circuit according to claim 1, characterized in that: The second switch circuit includes: a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor and an eleventh resistor; The emitter of the fifth transistor is connected to the output end of the first switch circuit, the collector of the fifth transistor is connected to one end of the sixth resistor, and the base of the fifth transistor is connected to the base of the sixth transistor; The emitter of the sixth transistor is connected to the output end of the first switch circuit, and the collector of the sixth transistor is connected to one end of the seventh resistor; The other end of the sixth resistor is connected to the base of the eighth transistor; the collector of the eighth transistor is connected to one end of the tenth resistor, and the other end of the tenth resistor is connected to the battery; The other end of the seventh resistor is connected to the base of the seventh transistor; the collector of the seventh transistor is connected to one end of the eleventh resistor, and the other end of the eleventh resistor is connected to the battery; One end of the eighth resistor is connected to the base of the sixth transistor, and the other end is connected to the power supply; One end of the ninth resistor is connected to the base of the sixth transistor, and the other end is grounded.

7. The electric vehicle protection circuit according to claim 2, characterized in that: The second switch circuit comprises: a ninth transistor, a tenth transistor and a fifth diode; The base of the triode is connected to the battery, the emitter of the triode is connected to the base of the ninth triode, and the collector of the triode is connected to the detection and output circuit; The emitter of the ninth transistor is grounded, and the collector of the ninth transistor is connected to the detection and output circuit; An anode of the fifth diode is grounded, and a cathode of the fifth diode is connected to the output circuit.

8. The electric vehicle protection circuit according to claim 7, characterized in that: The third switch circuit comprises: a fourteenth transistor, a first MOS transistor and a twelfth resistor; The emitter of the fourteenth triode is connected to the battery and grounded, the collector of the fourteenth triode is connected to one end of the twelfth resistor, and the other end of the twelfth resistor is connected to the gate of the first MOS tube; The source of the first MOS transistor is connected to the battery, and the drain of the first MOS transistor is connected to the output end of the second switch circuit.

9. The electric vehicle protection circuit according to claim 8, characterized in that: The charging circuit further includes a fourth switch circuit, and the fourth switch circuit includes: a second MOS transistor, a third MOS transistor and a sixth diode; The drain of the second MOS tube is connected to the charger, the gate of the second MOS tube is connected to the output end of the second switch circuit, and the source connected to the output end of the second switch circuit is connected to the source of the third MOS tube; The gate of the third MOS tube is connected to the gate of the second MOS tube, and the drain of the third MOS tube is connected to the battery; An anode of the sixth diode is connected to the source of the second MOS transistor, and a cathode of the sixth diode is connected to the gate of the second MOS transistor.

10. The electric vehicle protection circuit according to claim 9, characterized in that: The energy storage circuit comprises: a seventh diode and a first capacitor; An anode of the seventh diode is connected to the drain of the first MOS transistor, and a cathode of the seventh diode is connected to one end of the first capacitor and an output end of the second switch circuit; The other end of the first capacitor is connected to the output end of the detection and output circuit.

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