Electric vehicle charging protection device and method, terminal, electric vehicle and storage medium

Abstract

The invention relates to the technical field of electric vehicle control, in particular to an electric vehicle charging protection device and method, a terminal, an electric vehicle and a storage medium, the electric vehicle charging protection device comprises a voltage dividing and current limiting module, and the voltage dividing and current limiting module is connected between the output end of an auxiliary switching power supply and the input end of a controller module; the voltage dividing and current limiting module is used for converting a first voltage output by the auxiliary switching power supply into a second voltage and automatically limiting the current output of the auxiliary switching power supply when the voltage of a power grid fluctuates or the auxiliary switching power supply is abnormal; wherein the numerical value of the second voltage is smaller than that of the first voltage; and the controller module is used for detecting the second voltage and carrying out charging control or safety protection operation according to the second voltage. The power output of the auxiliary switching power supply can be effectively limited, and the safety and controllability of the charging process are ensured.

Description

Technical Field

[0001] The present invention relates to the field of electric vehicle control technology, and in particular to an electric vehicle charging protection device, method, terminal, electric vehicle and storage medium. Background Art

[0002] In the process of charging electric vehicles, the charging pile provides the necessary 12V low-voltage power supply for various electrical appliances on the electric vehicle through the low-voltage auxiliary line. According to the "GBT18487.1 Electric Vehicle Conductive Charging System" standard, the controller of the electric vehicle must first confirm that the low-voltage auxiliary power supply from the charging pile reaches the 12V standard before starting the subsequent charging process. However, due to power grid fluctuations and quality problems of the charging pile switching power supply itself, the output voltage of the low-voltage auxiliary power supply is often difficult to maintain stability, which has prompted many electric vehicle designs to abandon the direct use of auxiliary power supply, but the 12V detection is a national standard strategy and still needs to be retained.

[0003] like Figure 1 As shown in the figure, it is a schematic diagram of the current low-voltage auxiliary power connection, in which the positive output terminal (i.e., the A+ terminal) of the auxiliary switching power supply 1 is connected to the controller module 3 (usually the vehicle controller), the negative output terminal (i.e., the A- terminal) of the auxiliary switching power supply 1 is connected to the vehicle body 4, and the vehicle body 4 is connected to PE (protective grounding). When the power grid is stable and the quality of the auxiliary switching power supply 1 is reliable, it can ensure that the controller module 3 effectively detects the 12V output. However, this connection method and detection strategy hide significant safety hazards: when the power grid fluctuates or the auxiliary switching power supply 1 is abnormal, a voltage difference may occur between the A- terminal and PE of the auxiliary switching power supply 1, which not only violates the safety design principle, but also may cause serious accidents, such as wiring harness ablation or even local fire. There have been many similar cases in the aftermarket.

[0004] In-depth analysis found that when the grid voltage is unstable, a voltage difference will appear between the A-terminal and PE of the auxiliary switching power supply, and this difference changes with the fluctuation of the grid voltage, which may be positive or negative. What is particularly serious is that when this voltage difference persists and the charging pile load is high (such as the common 300W load), the wire between the A-terminal and PE will be subjected to a large amount of power consumption, heating up like a "resistance wire", and eventually causing the wire to burn or even catch fire.

[0005] Although existing patent documents such as CN210478420U have proposed a universal charging pile auxiliary power supply identification and conversion circuit, it has failed to fully consider the impact of power grid fluctuations and the quality of the auxiliary switch power supply on the voltage stability of the A-terminal, and directly grounded the A-terminal, which poses potential risks. Similarly, the charging pile auxiliary power supply output voltage adaptive control method disclosed in patent document CN107231034B is used to switch the 12V and 24V outputs of the charging pile auxiliary power supply to adapt to different vehicle voltage levels (24V system and 12V system). Although this method solves the adaptation problem of different vehicle voltage levels, this method also does not consider the impact of power grid fluctuations and the quality of the auxiliary switch power supply on the voltage stability of the A-terminal.

[0006] Therefore, it is necessary to develop a new electric vehicle charging protection device, method, terminal, electric vehicle and storage medium. Summary of the invention

[0007] The object of the present invention is to provide an electric vehicle charging protection device, method, terminal, electric vehicle and storage medium, which can effectively limit the power output of the auxiliary switching power supply to ensure the safety and controllability of the charging process.

[0008] In a first aspect, an electric vehicle charging protection device according to the present invention comprises a voltage-dividing and current-limiting module, wherein the voltage-dividing and current-limiting module is connected between an output end of an auxiliary switching power supply and an input end of a controller module;

[0009] The voltage-dividing and current-limiting module is used to convert the first voltage output by the auxiliary switching power supply into a second voltage, and automatically limit the current output of the auxiliary switching power supply when the grid voltage fluctuates or the auxiliary switching power supply is abnormal; wherein the value of the second voltage is smaller than the first voltage;

[0010] The controller module is used to detect the second voltage and perform charging control or safety protection operation according to the second voltage.

[0011] Optionally, the voltage-dividing and current-limiting module includes a first voltage-dividing and current-limiting unit, a second voltage-dividing and current-limiting unit, a current-limiting resistor unit and an isolation inductor unit;

[0012] One end of the first voltage-dividing and current-limiting unit is connected to the positive output end of the auxiliary switching power supply;

[0013] The other end of the first voltage-dividing and current-limiting unit is connected to the negative output end of the auxiliary switching power supply through the second voltage-dividing and current-limiting unit and the current-limiting resistor unit in sequence;

[0014] The connection point between the second voltage-dividing and current-limiting unit and the current-limiting resistor unit is connected to PE via an isolation inductor unit;

[0015] The connection point of the first voltage-dividing and current-limiting unit and the second voltage-dividing and current-limiting unit is connected to the input end of the controller module, ensuring that the current and voltage flow correctly inside the module, while the setting of the isolation inductor unit improves the anti-interference ability and safety of the circuit.

[0016] Optionally, the first voltage-dividing and current-limiting unit includes at least one resistor, or a lamp, or a motor;

[0017] The second voltage-dividing and current-limiting unit includes at least one resistor;

[0018] The current limiting resistor unit includes at least one resistor;

[0019] The isolation inductor unit includes at least one inductor. The power of the auxiliary switching power supply is consumed through a resistor, or electrical equipment such as a motor and a lamp. For example, the motor can be used for ventilation and heat dissipation lamp systems of electric vehicles, and the lamp can be used for heat dissipation lamp systems.

[0020] Optionally, the resistance values ​​of the first voltage-dividing and current-limiting unit, the second voltage-dividing and current-limiting unit, and the current-limiting resistor unit are all greater than 1000 ohms, and the ratio of the resistance values ​​of any two units does not exceed 2. By setting the resistance values ​​of the first voltage-dividing and current-limiting unit, the second voltage-dividing and current-limiting unit, and the current-limiting resistor unit to be greater than 1000 ohms, the magnitude of the current is effectively limited, and overheating and damage caused by excessive current are prevented. The ratio of the resistance values ​​of any two units does not exceed 2. This design ensures that the voltage distribution in the circuit is relatively uniform, and avoids voltage instability caused by excessive differences in resistance values.

[0021] Optionally, the resistance values ​​of the first voltage-dividing current-limiting unit, the second voltage-dividing current-limiting unit and the current-limiting resistor unit are equal. When the resistance values ​​of the first voltage-dividing current-limiting unit, the second voltage-dividing current-limiting unit and the current-limiting resistor unit are equal, the circuit design is simpler and more unified, reducing the manufacturing cost and maintenance difficulty. Equal resistance values ​​also mean that the voltage drop and current distribution in the circuit are more uniform, which helps to improve the performance stability and reliability of the entire charging protection device.

[0022] Optionally, a voltage-stabilizing capacitor group is further included, wherein the voltage-stabilizing capacitor group includes at least one voltage-stabilizing capacitor, and the configuration of the voltage-stabilizing capacitor group includes at least one of the following situations:

[0023] One or more voltage-stabilizing capacitors are connected between the live wire and PE;

[0024] One or more voltage stabilizing capacitors are connected between the neutral line and PE;

[0025] One or more voltage stabilizing capacitors are connected between the positive output terminal of the auxiliary switching power supply and PE;

[0026] One or more voltage stabilizing capacitors are connected between the negative output terminal of the auxiliary switching power supply and PE to stabilize the voltage and prevent voltage fluctuations.

[0027] In a second aspect, an electric vehicle charging protection method according to the present invention adopts the electric vehicle charging protection device according to the present invention, and the method comprises the following steps:

[0028] When it is detected that the electric vehicle is connected to the charging pile, the second voltage is automatically collected and it is determined whether the second voltage is within the safe voltage range; if the second voltage is not within the safe voltage range, the detection is repeated and it is determined whether the second voltage is within the safe voltage range; if the number of repeated detections reaches a preset number of times and the second voltage is still not within the safe voltage range, it is determined that the voltage state is continuously abnormal, the charging operation is suspended, and the charging pile fault information is reported; if the second voltage is within the safe voltage range, the charging connection operation is performed;

[0029] During charging, if it is detected that the second voltage is not within the standard voltage range but within the safe voltage range, and the duration exceeds the warning time threshold, charging will continue and the abnormal voltage fluctuation information of the charging pile will be reported; if it is detected that the second voltage is not within the safe voltage range and the duration of the voltage abnormality exceeds the safe time threshold, charging will be suspended and the charging pile voltage failure will be reported.

[0030] In a third aspect, a terminal described in the present invention includes a memory and a controller, wherein the memory stores a computer-readable program, and when the computer-readable program is called by the controller, it can execute the steps of the electric vehicle charging protection method described in the present invention.

[0031] In a fourth aspect, an electric vehicle described in the present invention adopts the electric vehicle charging protection device described in the present invention.

[0032] In a fifth aspect, a storage medium described in the present invention stores a computer-readable program therein, and when the computer-readable program is called, it can execute the steps of the electric vehicle charging protection method described in the present invention.

[0033] Beneficial effects of the present invention:

[0034] During the charging process of an electric vehicle through a charging pile, the present invention can not only effectively limit the power output of the auxiliary switching power supply to ensure the safety and controllability of the charging process, but also innovatively convert the traditional directly collected high voltage (such as the common 12V) into a safer low voltage (i.e., the second voltage, whose value is less than 12V) for detection. This design complies with the industry standard GBT18487.1 and sets a new benchmark for electric vehicle charging safety.

[0035] The core function of the voltage-dividing and current-limiting module in the present invention is that it can respond quickly and automatically limit the current output when the grid voltage fluctuates or the auxiliary switching power supply itself has quality problems, thereby effectively preventing safety hazards such as wiring harness ablation caused by unstable voltage or excessive current. At the same time, by detecting the converted low voltage (second voltage), the controller module can more accurately execute the charging control strategy to ensure that the charging process is both efficient and safe.

[0036] In addition, when a voltage fault is detected in the charging pile, the fault information of the charging pile is reported to prevent damage to the battery of the electric vehicle. When a voltage fluctuation of the charging pile is detected, abnormal voltage fluctuation information of the charging pile is reported, which can issue an early warning to other electric vehicle users who have not adopted the electric vehicle charging protection device, reminding them to avoid using the charging pile, thereby achieving all-round protection of charging safety.

[0037] In summary, the electric vehicle charging protection device and charging protection method described in the present invention not only improve the safety and stability of the charging process, but also realize real-time monitoring and early warning of the charging pile status through intelligent and networked means, providing electric vehicle users with a more convenient and safe charging experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of the prior art;

[0039] Figure 2 The principle framework of the electric vehicle charging protection device described in the embodiment of this application Figure 1 ;

[0040] Figure 3 The principle framework of the electric vehicle charging protection device described in the embodiment of this application Figure 2 ;

[0041] Figure 4 The principle framework of the electric vehicle charging protection device described in the embodiment of this application Figure 3 ;

[0042] Figure 5 This is a flowchart of an embodiment of the present application;

[0043] Figure 6 A flow chart of a method for calibrating a safe voltage range and a standard voltage range according to an embodiment of the present application;

[0044] Figure 7 This is a flow chart of a method for calibrating a warning time threshold according to an embodiment of the present application;

[0045] Figure 8 A specific flow chart of the electric vehicle charging protection method described in the embodiment of the present application;

[0046] Fig. 9 This is a functional block diagram of the terminal described in the embodiment of the present application.

[0047] In the figure: 1- auxiliary switching power supply, 2- voltage divider and current limiting module, 21- first voltage divider and current limiting unit, 22- second voltage divider and current limiting unit, 23- current limiting resistor unit, 24- isolation inductor unit, 3- controller module, 4- vehicle body, 5- memory, 6- controller. DETAILED DESCRIPTION

[0048] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0049] like Figure 2 As shown, in an embodiment of the present application, an electric vehicle charging protection device includes a voltage-dividing and current-limiting module 2, which is connected between the output end of the auxiliary switching power supply 1 and the input end of the controller module 3. The voltage-dividing and current-limiting module 2 is used to convert the first voltage output by the auxiliary switching power supply 1 into a second voltage, and automatically limit the current output of the auxiliary switching power supply 1 when the grid voltage fluctuates or the auxiliary switching power supply 1 is abnormal; wherein the value of the second voltage is less than the first voltage. The controller module 3 is used to detect the second voltage and perform charging control or safety protection operations according to the second voltage.

[0050] like Figures 2 to 4 As shown, in a possible embodiment, the voltage-dividing and current-limiting module 2 includes a first voltage-dividing and current-limiting unit 21, a second voltage-dividing and current-limiting unit 22, a current-limiting resistor unit 23 and an isolation inductor unit 24. One end of the first voltage-dividing and current-limiting unit 21 is connected to the positive output end of the auxiliary switching power supply 1. The other end of the first voltage-dividing and current-limiting unit 21 is connected to the negative output end of the auxiliary switching power supply 1 after passing through the second voltage-dividing and current-limiting unit 22 and the current-limiting resistor unit 23 in sequence. The connection point between the second voltage-dividing and current-limiting unit 22 and the current-limiting resistor unit 23 is connected to PE (i.e., protective grounding) after passing through the isolation inductor unit 24. The connection point between the first voltage-dividing and current-limiting unit 21 and the second voltage-dividing and current-limiting unit 22 is connected to the input end of the controller module 3. It ensures that the current and voltage flow correctly inside the module, and at the same time, the setting of the isolation inductor unit 24 improves the anti-interference ability and safety of the circuit.

[0051] like Figure 2As shown, in a possible embodiment, the first voltage-dividing and current-limiting unit 21 includes at least one resistor, the second voltage-dividing and current-limiting unit 22 includes at least one resistor; the current-limiting resistor unit 23 includes at least one resistor; and the isolation inductor unit 24 includes at least one inductor. The power of the auxiliary switching power supply 1 is consumed through the resistor.

[0052] like Figure 3 As shown, in a possible embodiment, the first voltage-dividing and current-limiting unit 21 includes at least one lamp, the second voltage-dividing and current-limiting unit 22 includes at least one resistor; the current-limiting resistor unit 23 includes at least one resistor; and the isolation inductor unit 24 includes at least one inductor. The power of the auxiliary switching power supply 1 is consumed by the lamp. The lamp can be used for the heat dissipation lamp system.

[0053] like Figure 4 As shown, in a possible embodiment, the first voltage-dividing and current-limiting unit 21 includes at least one motor, the second voltage-dividing and current-limiting unit 22 includes at least one resistor; the current-limiting resistor unit 23 includes at least one resistor; and the isolation inductor unit 24 includes at least one inductor. The power of the auxiliary switching power supply 1 is consumed by the motor. The motor can be used for the ventilation and heat dissipation lamp system of the electric vehicle.

[0054] like Figures 2 to 4 As shown, in a possible embodiment, the resistance values ​​of the first voltage-dividing current-limiting unit 21, the second voltage-dividing current-limiting unit and the current-limiting resistor unit 23 are all greater than 1000 ohms, and the ratio of the resistance values ​​of any two units does not exceed 2. By setting the resistance values ​​of the first voltage-dividing current-limiting unit 21, the second voltage-dividing current-limiting unit and the current-limiting resistor unit 23 to be greater than 1000 ohms, the current is effectively limited to prevent overheating and damage caused by excessive current. The ratio of the resistance values ​​of any two units does not exceed 2. This design ensures that the voltage distribution in the circuit is relatively uniform and avoids voltage instability caused by excessive resistance value differences.

[0055] like Figures 2 to 4 As shown, in a possible embodiment, the resistance values ​​of the first voltage-dividing current-limiting unit 21, the second voltage-dividing current-limiting unit and the current-limiting resistor unit 23 are equal. When the resistance values ​​of the first voltage-dividing current-limiting unit 21, the second voltage-dividing current-limiting unit 22 and the current-limiting resistor unit 23 are equal, the circuit design is simpler and more unified, reducing the manufacturing cost and maintenance difficulty. Equal resistance values ​​also mean that the voltage drop and current distribution in the circuit are more uniform, which helps to improve the performance stability and reliability of the entire charging protection device.

[0056] like Figure 2 As shown, the following description is made by taking the first voltage-dividing and current-limiting unit 21 as the resistor R1, the second voltage-dividing and current-limiting unit 22 as the resistor R2, the current-limiting resistor unit 23 as the resistor R3, and R1=R2=R3=1.5KΩ as an example:

[0057] When this option is adopted, when the positive output terminal of the auxiliary switching power supply 1 (i.e., the A+ terminal of the auxiliary switching power supply 1) is 12V and the negative output terminal of the auxiliary switching power supply 1 (i.e., the A- terminal of the auxiliary switching power supply 1) is 0V, the voltage value of the second voltage (i.e., U1) detected by the controller module 3 is 6V (i.e., 12*R2 / (R1+R2)=12*1500 / 3000=6V). If the grid voltage fluctuates, for example: when the A+ terminal of the auxiliary switching power supply 1 is 8V and the A- terminal of the auxiliary switching power supply 1 is -4V, the sum of the voltages of the A+ terminal of the auxiliary switching power supply 1 and the A- terminal of the auxiliary switching power supply 1 is 12V, and the U1 detected in the controller module 3 is 4V. At this time, the output current of the A- terminal of the auxiliary switching power supply 1 is 2.67mA (i.e., I=12 / (R1+R2+R3)=12 / 4500=2.67mA). According to the heating formula Q=I 2 RT, where Q represents heat, R represents the resistance value of the wire connecting the A-terminal of the auxiliary switching power supply 1 and PE, and T represents the charging time. Since I is small, Q will not be large, which will not cause line abnormality.

[0058] like Figures 2 to 4 As shown, in a possible embodiment, an electric vehicle charging protection device further includes a voltage stabilizing capacitor group, the voltage stabilizing capacitor group includes at least one voltage stabilizing capacitor, and its configuration includes at least one of the following situations:

[0059] One or more voltage-stabilizing capacitors are connected between the live wire and PE; one or more voltage-stabilizing capacitors are connected between the neutral wire and PE; one or more voltage-stabilizing capacitors are connected between the positive output terminal of the auxiliary switching power supply 1 and PE; one or more voltage-stabilizing capacitors are connected between the negative output terminal of the auxiliary switching power supply 1 and PE. It is used to stabilize the voltage and prevent voltage fluctuations.

[0060] like Figures 2 to 4 As shown, the functions of each electronic component are described below:

[0061] Capacitor C1: voltage-stabilizing capacitor between L (live wire) and PE.

[0062] Capacitor C2: voltage-stabilizing capacitor between N (neutral line) and PE.

[0063] Capacitor C3: A voltage-stabilizing capacitor between the A+ terminal and PE of the auxiliary switching power supply 1.

[0064] Capacitor C4: A voltage stabilizing capacitor between the A- terminal and PE of the auxiliary switching power supply 1.

[0065] Resistor R1: Voltage divider and current limiting resistor used at the A+ end of auxiliary switching power supply 1.

[0066] Resistor R2: A voltage divider and current limiting resistor used at the A+ end of the auxiliary switching power supply 1.

[0067] Resistor R3: Current limiting resistor used at the A- terminal of the auxiliary switching power supply 1.

[0068] Resistor L1: Isolates the inductor to prevent AC interference.

[0069] In an embodiment of the present application, an electric vehicle charging protection method is provided, which uses an electric vehicle charging protection device as in an embodiment of the present application, and the method comprises the following steps:

[0070] When it is detected that the electric vehicle is connected to the charging pile, the second voltage is automatically collected and it is determined whether the second voltage is within the safe voltage range; if the second voltage is not within the safe voltage range, the detection is repeated and it is determined whether the second voltage is within the safe voltage range; if the number of repeated detections reaches the preset number of times and the second voltage is still not within the safe voltage range, it is confirmed that the voltage state is continuously abnormal, the charging operation is suspended, and the charging pile fault information is reported; if the second voltage is within the safe voltage range, the charging connection operation is performed.

[0071] During charging, if it is detected that the second voltage is not within the standard voltage range but within the safe voltage range, and the duration exceeds the warning time threshold, charging will continue and the abnormal voltage fluctuation information of the charging pile will be reported. If it is detected that the second voltage is not within the safe voltage range and the duration of the voltage abnormality exceeds the safe time threshold, charging will be suspended and the charging pile voltage fault will be reported.

[0072] like Figure 8 As shown, as an example, a method for protecting charging of an electric vehicle specifically includes the following steps:

[0073] Step 11: The electric vehicle is connected to the charging pile, and the controller module 3 detects the second voltage (ie, U1). The controller module 3 determines whether the voltage value of the second voltage is within the safe voltage range. If not, step 12 is executed, otherwise step 13 is executed.

[0074] Step 12: At an interval of 10 seconds, perform three tests on the second voltage to determine whether the second voltage is within a safe voltage range. If it is still not within the safe voltage range after three tests, suspend charging and report a charging pile voltage failure to the user, which may cause system overvoltage and affect the life of the battery.

[0075] Step 13: The controller module 3 confirms that the current charger meets the charging start-up conditions and continues the charging connection.

[0076] Step 14: After completing the charging connection, the controller module 3 continues to detect the second voltage and determines whether the voltage value of the second voltage is within the standard voltage range. If so, continue charging; if not, proceed to step 15.

[0077] Step 15: Determine whether the second voltage is within the safe voltage range and the duration exceeds the warning time threshold. If the second voltage is within the safe voltage range and the duration exceeds the warning time threshold, continue charging and report abnormal voltage fluctuation of the charging pile. Abnormal voltage fluctuation of the charging pile may cause abnormal charging of vehicles with A - direct - PE. By reporting to the cloud platform, it is notified that other vehicles with A - direct - PE in the company cannot charge at this charging pile. If not, proceed to Step 16.

[0078] Step 16: Determine whether the second voltage is within the safe voltage range and the duration exceeds the safe time threshold. If the second voltage is not within the safe voltage range and the duration exceeds the safe time threshold, suspend charging and report a charging pile voltage fault to notify the user, which may cause overvoltage and affect the battery life, etc. If not, continue charging and continuously detect the second voltage.

[0079] As Figure 6 shown, in the embodiment of the present application, the safe voltage range is (U1min, U1max), and the standard voltage range is (U1min standard, U1max standard), where U1min, U1max, U1min standard, and U1max standard are all obtained by calibration. The specific process is as follows:

[0080] Step 21: Input the standard upper - limit voltage, measure the voltage value of U1, and record the voltage value of U1.

[0081] Step 22: Input the standard lower - limit voltage, measure the voltage value of U1, and record the voltage value of U1.

[0082] Step 23: Input the standard upper - limit + N% voltage, measure the voltage value of U1, and record the voltage value of U1.

[0083] Step 24: Input the standard lower - limit - N% voltage, measure the voltage value of U1, and record the voltage value of U1.

[0084] Step 25: Complete the measurement of the upper and lower limit voltages of the output of the auxiliary switching power supply 1 of multiple mainstream charging piles in the market according to Steps 11 to 14.

[0085]

[0086] Step 26: Take the measurement of the upper and lower limit voltages of the output of the auxiliary switching power supply 1 of four mainstream charging piles in the market as an example:

[0087] Take the maximum value among U1max standard ', U1max standard ", U1max standard '", and U1max standard "" as U1max standard.

[0088] Take the minimum value among U1min standard ', U1min standard ", U1min standard '" and U1min standard "" as U1min standard.

[0089] Take the maximum value among U1max ', U1max ", U1max '" and U1max "" as U1max.

[0090] Take the minimum value among U1min ', U1min ", U1min '" and U1min "" as U1min.

[0091] That is, the safe voltage range is (U1min, U1max), and the standard voltage range is (U1min standard, U1max standard).

[0092] As Figure 7 shown, in a specific embodiment, the method for calibrating the warning time threshold is as follows:

[0093] Step 31:

[0094] 1. Connect the A - terminal of the auxiliary switch power supply 1 to PE with a 0.35 mm 2 wire, input the standard upper limit voltage, and record the wire smoking time S1.

[0095] 2. Connect the A - terminal of the auxiliary switch power supply 1 to PE with a 0.5 mm 2 wire; input the standard upper limit voltage, and record the wire smoking time S2. ...

[0097] K. Connect the A - terminal of the auxiliary switch power supply 1 to PE with an N mm 2 wire; input the standard upper limit voltage, and record the wire smoking time SK.

[0098] The recorded data is as follows:

[0099] Serial number Input voltage U1 voltage Wire diameter Smoking time 1 Standard upper limit voltage … <![CDATA[0.35mm 2 ]]> S1 2 Standard upper limit voltage … <![CDATA[0.5mm 2 ]]> S2 3 Standard upper limit voltage … … … … … … … … K Standard upper limit voltage … <![CDATA[Nmm 2 ]]> SK

[0100] Step 32:

[0101] 1. Connect the A - terminal of the auxiliary switch power supply 1 to PE with a 0.35 mm 2 wire; input the standard lower limit voltage, and record the wire smoking time S11.

[0102] 2. Connect the A - terminal of the auxiliary switch power supply 1 to PE with a 0.5 mm 2 wire; input the standard lower limit voltage, and record the wire smoking time S12. ...

[0104] K. Connect the A - terminal of the auxiliary switch power supply 1 to PE with an N mm 2Connect the A-terminal of the auxiliary switch power supply 1 and PE; input the standard lower limit voltage and record the wire smoking time S1K.

[0105] The recorded data is as follows:

[0106] Serial number Input voltage U1 voltage Wire diameter Smoking time 1 Standard lower limit voltage … <![CDATA[0.35mm 2 ]]> S11 2 Standard lower limit voltage … <![CDATA[0.5mm 2 ]]> S12 3 Standard lower limit voltage … … … … … … … … K Standard lower limit voltage … <![CDATA[Nmm 2 ]]> S1K

[0107] Step 33: Take the minimum value of all wire smoking times as the warning time threshold.

[0108] like Fig. 9 As shown, in an embodiment of the present application, a terminal includes a memory 5 and a controller 6, and a computer-readable program is stored in the memory 5. When the computer-readable program is called by the controller 6, the steps of the electric vehicle charging protection method described in the embodiment of the present application can be executed.

[0109] In an embodiment of the present application, an electric vehicle adopts the electric vehicle charging protection device as described in the embodiment of the present application.

[0110] In an embodiment of the present application, a storage medium stores a computer-readable program, and when the computer-readable program is called, it can execute the steps of the electric vehicle charging protection method as described in the embodiment of the present application.

[0111] In an embodiment of the present application, the storage medium may be a tangible storage medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or equipment. The storage medium may be a machine-readable signal storage medium or a machine-readable storage medium. The storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or equipment, or any suitable combination of the foregoing. A more specific example of a storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0112] The above-mentioned embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above-mentioned embodiments. Any other changes, modifications, substitutions, combinations and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement modes and shall be included in the protection scope of the present invention.

Claims

1. An electric vehicle charging protection device, characterized in that: It comprises a voltage-dividing and current-limiting module (2), wherein the voltage-dividing and current-limiting module (2) is connected between the output end of the auxiliary switching power supply (1) and the input end of the controller module (3); The voltage-dividing and current-limiting module (2) is used to convert a first voltage output by the auxiliary switching power supply (1) into a second voltage, and automatically limit the current output of the auxiliary switching power supply (1) when the grid voltage fluctuates or the auxiliary switching power supply (1) is abnormal; wherein the value of the second voltage is smaller than the first voltage; The controller module (3) is used to detect the second voltage and perform charging control or safety protection operations according to the second voltage.

2. The electric vehicle charging protection device according to claim 1, characterized in that: The voltage-dividing and current-limiting module (2) comprises a first voltage-dividing and current-limiting unit (21), a second voltage-dividing and current-limiting unit (22), a current-limiting resistor unit (23) and an isolation inductor unit (24); One end of the first voltage dividing and current limiting unit (21) is connected to the positive output end of the auxiliary switching power supply (1); The other end of the first voltage-dividing and current-limiting unit (21) is connected to the negative output end of the auxiliary switching power supply (1) via the second voltage-dividing and current-limiting unit (22) and the current-limiting resistor unit (23) in sequence; The connection point between the second voltage-dividing and current-limiting unit (22) and the current-limiting resistor unit (23) is connected to PE via the isolation inductor unit (24); The connection point between the first voltage-dividing and current-limiting unit (21) and the second voltage-dividing and current-limiting unit (22) is connected to the input end of the controller module (3).

3. The electric vehicle charging protection device according to claim 2, characterized in that: The first voltage-dividing and current-limiting unit (21) comprises at least one resistor, or a lamp, or a motor; The second voltage-dividing and current-limiting unit (22) comprises at least one resistor; The current limiting resistor unit (23) comprises at least one resistor; The isolation inductor unit (24) comprises at least one inductor.

4. The electric vehicle charging protection device according to claim 3, characterized in that: The resistance values ​​of the first voltage-dividing and current-limiting unit (21), the second voltage-dividing and current-limiting unit (22) and the current-limiting resistor unit (23) are all greater than 1000 ohms, and the ratio of the resistance values ​​of any two units does not exceed 2.

5. The electric vehicle charging protection device according to claim 4, characterized in that: The resistance values ​​of the first voltage-dividing and current-limiting unit (21), the second voltage-dividing and current-limiting unit (22), and the current-limiting resistor unit (23) are equal.

6. The electric vehicle charging protection device according to claim 1, characterized in that: The invention also includes a voltage stabilizing capacitor group, wherein the voltage stabilizing capacitor group includes at least one voltage stabilizing capacitor, and the configuration method thereof includes at least one of the following situations: One or more voltage-stabilizing capacitors are connected between the live wire and PE; One or more voltage stabilizing capacitors are connected between the neutral line and PE; One or more voltage stabilizing capacitors are connected between the positive output terminal of the auxiliary switching power supply (1) and PE; One or more voltage stabilizing capacitors are connected between the negative output terminal of the auxiliary switching power supply (1) and PE.

7. A method for protecting charging of an electric vehicle, characterized in that: Using the electric vehicle charging protection device according to any one of claims 1 to 6, the method comprises the following steps: When it is detected that the vehicle is connected to the charging pile, the second voltage is automatically collected and it is determined whether the second voltage is within the safe voltage range; if the second voltage is not within the safe voltage range, the detection is repeated and it is determined whether the second voltage is within the safe voltage range; if the number of repeated detections reaches a preset number of times and the second voltage is still not within the safe voltage range, it is determined that the voltage state is continuously abnormal, the charging operation is suspended, and the charging pile fault information is reported; if the second voltage is within the safe voltage range, the charging connection operation is performed; During charging, if it is detected that the second voltage is not within the standard voltage range but within the safe voltage range, and the duration exceeds the warning time threshold, charging will continue and the abnormal voltage fluctuation information of the charging pile will be reported; if it is detected that the second voltage is not within the safe voltage range and the duration of the voltage abnormality exceeds the safe time threshold, charging will be suspended and the charging pile voltage failure will be reported.

8. A terminal, characterized in that: It comprises a memory (5) and a controller (6), wherein the memory (5) stores a computer-readable program, and when the computer-readable program is called by the controller (6), the steps of the electric vehicle charging protection method as claimed in claim 7 can be executed.

9. An electric vehicle, characterized in that: An electric vehicle charging protection device as described in any one of claims 1 to 6 is used.

10. A storage medium, characterized in that: A computer-readable program is stored therein, and when the computer-readable program is called, the steps of the electric vehicle charging protection method as described in claim 7 can be executed.

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