Charging gun leakage monitoring system and charging gun

Abstract

The present invention provides a charging gun leakage monitoring system and a charging gun, comprising a data acquisition module for acquiring a resistance value in a detection circuit and a temperature value inside the gun, a resistance abnormality judgment module for judging whether there is leakage, a leakage source comparison module for judging whether the cold source type in a liquid cooling tube is water, a leakage analysis selection module for judging whether the resistance value is restored to the initially acquired resistance value within a preset time period when the cold source type is water, so as to output leakage inside the gun or external penetration, and when the cold source type is not water, substituting the currently acquired temperature value inside the gun into a preset resistance change model to output the cold source resistance change amount and the water resistance change amount, and outputting leakage inside the gun or external penetration by comparing with the actual resistance change amount; a leakage control module for controlling the charging gun to be powered off or ignored according to the output result; the present invention has the advantage of ensuring that the charging gun can detect whether there is leakage inside the gun during the process of being plugged into a vehicle body for charging, so as to ensure that the charging gun can be continuously charged under safe conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of charging gun detection, and more particularly to a charging gun leakage monitoring system. Background Art

[0002] With the rapid development of the new energy electric vehicle industry and the strong call from society for low-carbon travel, environmental protection and resource conservation, electric vehicles, as a pollution-free new energy green transportation tool, are becoming more and more popular and widely used. In this context, the charging gun, as a key facility in the charging process of electric vehicles, is particularly important for its safety and functionality.

[0003] When the charging gun is plugged into the vehicle interface for charging, the temperature inside the gun body will gradually increase. Therefore, current charging guns use liquid cooling and air cooling to cool down. Liquid cooling itself has the risk of leakage, and there is also the risk of external water vapor penetration during the manufacture of the gun body. When there is internal leakage, it is easy to cause safety hazards to the charging core. The existing charging guns do not monitor whether there is leakage inside the gun body, etc., and only detect the temperature of the gun body. Therefore, the existing charging guns cannot meet the needs of charging safety. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention aims to provide a charging gun leakage monitoring system.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A charging gun leakage monitoring system, comprising:

[0007] The data acquisition module obtains the resistance value of the detection circuit set in the charging gun at continuous moments, and obtains the temperature value inside the gun at continuous moments collected by the temperature sensor in the charging gun;

[0008] The resistance abnormality judgment module judges whether the resistance value obtained at the current moment is equal to the resistance value obtained at the initial moment, and outputs a leakage instruction or a normal instruction according to the judgment result;

[0009] The leakage source comparison module, when the judgment result is a leakage instruction, retrieves the cold source information preset in the system and passes into the liquid cooling pipe, and judges whether the cold source type in the cold source information is water;

[0010] The leakage analysis selection module, when the cold source type is water, determines whether the resistance value in the preset time period has recovered to the resistance value obtained at the initial moment according to the temperature value in the gun obtained at the current moment, and outputs the leakage in the gun or external penetration according to the judgment result; when the cold source type is not water, substitutes the temperature value in the gun obtained at the current moment into the preset resistance change model to output the cold source resistance change and the water resistance change, and then analyzes the actual resistance change within a certain moment when the temperature in the gun remains unchanged, and compares it with the cold source resistance change and the water resistance change, and outputs the leakage in the gun or external penetration according to the comparison result;

[0011] The leakage control module controls the charging gun to cut off the power when the comparison result is leakage inside the gun, and controls the charging gun to ignore when the comparison result is external penetration.

[0012] Furthermore, it also includes a resistance change model construction module, which constructs a resistance change model using a temperature resistance algorithm for different gun temperature values ​​and cold source information. The cold source information includes leakage liquid conductivity and leakage liquid evaporation rate, and the gun temperature value corresponds to the leakage liquid evaporation rate one by one.

[0013] Furthermore, the temperature resistance algorithm is configured as follows:

[0014] ,

[0015] in, is the temperature inside the gun, is the leakage conductivity, is the evaporation rate of the leaked liquid at the temperature inside the gun, For time, To detect the change in resistance in the circuit.

[0016] Furthermore, the data acquisition module obtains the wind speed value of the air cooling in the charging gun and the air inlet humidity value at the air inlet end, and obtains the humidity value inside the gun collected by the humidity sensor in the charging gun;

[0017] It also includes a liquid leakage verification module, which uses the liquid leakage instruction output from the resistance abnormality judgment module as a trigger condition, calculates the dehumidification time value for the humidity value inside the gun to reach the inlet humidity value through a dehumidification algorithm according to the wind speed value, the inlet humidity value, the humidity value inside the gun and the temperature value inside the gun, and then compares the dehumidification time value with a preset time threshold, and verifies the result output by the leakage analysis selection module according to the comparison result.

[0018] Furthermore, the dehumidification algorithm is configured as follows:

[0019] ,

[0020] ,

[0021] ,

[0022] in, is the dehumidification time value, is the wind speed value, is the humidity value in the gun, is the temperature inside the gun, is the inlet air humidity value, is the proportionality constant, They are the first coefficient, the second coefficient and the third coefficient respectively.

[0023] Furthermore, the leakage verification module includes a leakage verification submodule,

[0024] The liquid leakage verification submodule adjusts the flow rate of the cold source in the liquid cooling tube, and obtains the humidity value in the gun after adjusting the flow rate as the humidity control value in the gun, and then obtains the temperature value in the gun after adjusting the flow rate as the temperature control value in the gun, and then calculates the humidity value in the gun, the temperature value in the gun, the wind speed value and the inlet humidity value through the dehumidification algorithm again to obtain the dehumidification time verification value, and compares the dehumidification time verification value with the dehumidification time value, and performs a second verification on the verification result output by the liquid leakage verification module according to the comparison result.

[0025] Furthermore, it also includes a liquid leakage alarm module, when the secondary verification result output by the liquid leakage verification submodule is external penetration, the wind speed value in the air cooling is adjusted, the difference between the inlet humidity value and the outlet humidity value before the wind speed is adjusted is calculated as the first difference value, and the difference between the inlet humidity value and the outlet humidity value after the wind speed is adjusted is calculated as the second difference value, the first difference value is compared with the second difference value, if the second difference value is greater than the first difference value, then the instruction of excessive water vapor penetration is output, otherwise, the normal instruction is output;

[0026] When the leakage control module obtains the instruction of a large amount of water vapor penetration, it controls the charging gun to increase the wind speed and controls the temperature inside the gun to reduce the liquid cooling flow rate at a safe temperature.

[0027] Furthermore, the duration of the preset time period is the same as the preset time-consuming threshold.

[0028] A charging gun comprises a gun body, wherein a detection chip is arranged in the gun body, a detection circuit and an actuator are arranged in the detection chip, and a liquid leakage monitoring system is arranged in the actuator.

[0029] Furthermore, the detection chip is arranged on the inner wall of the gun body, and the detection chip is provided with a plurality of detection slots with notches facing upwards. The detection circuit includes an impedance detection unit, and the impedance detection unit includes a plurality of detection resistors arranged in series. The detection resistors are arranged in the detection slots, and each detection resistor is arranged corresponding to a detection slot.

[0030] The beneficial effects of the present invention are as follows: by analyzing the change of resistance through the detection circuit arranged in the gun body, and analyzing according to the type of cold source in the liquid cooling tube, a corresponding analysis strategy is selected, so that when the cold source is water or not water, it can be analyzed respectively to obtain whether it is liquid cooling tube leakage or external water vapor penetration, and the corresponding control strategy is matched according to the source of the leakage, which can ensure that whether the charging gun is leaking in the gun during the process of being plugged into the vehicle body for charging, and ensure that the charging gun can continue to charge under safe conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is the overall flow chart of the present invention;

[0032] Figure 2 is a structural diagram of the charging gun in the present invention;

[0033] Figure 3 It is a schematic diagram of the charging gun leakage monitoring system in the present invention.

[0034] Figure numerals: 1. gun body; 2. detection chip. DETAILED DESCRIPTION

[0035] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. The same parts are represented by the same reference numerals. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the accompanying drawings, and the words "bottom surface" and "top surface", "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0036] Since the temperature of the current charging gun gradually increases during the charging process, the charging gun uses liquid cooling and air cooling to cool down. Liquid cooling itself has the risk of leakage. When the gun body (1) is manufactured, there is also the risk of external water vapor penetration. When there is leakage inside, it is easy to cause safety hazards to the charging core. The existing charging gun does not monitor whether there is leakage inside the gun body (1), etc., and only detects the temperature of the gun body (1). Therefore, the present invention designs such a charging gun leakage monitoring system, such as Figure 1 As shown, it includes: a data acquisition module, a resistance abnormality judgment module, a leakage source comparison module, a leakage analysis selection module and a leakage control module, and a charging gun is designed accordingly, such as Figure 2As shown, the gun body (1) includes a detection chip (2) on the inner wall of the gun body (1), a detection circuit and an actuator are arranged in the detection chip (2), a leakage monitoring system is arranged in the actuator, a plurality of detection slots with notches upward are arranged on the detection chip (2), the detection circuit includes an impedance detection unit, the impedance detection unit includes a plurality of detection resistors arranged in series, the detection resistors are arranged in the detection slots, and each detection resistor is arranged corresponding to a detection slot. When liquid leaks in the gun or external water vapor penetrates, liquids will be gathered in the detection slots respectively. Initially, the detection resistors in the impedance detection unit in the detection circuit are connected in series, and can be calculated as the total resistance , and when there is liquid in the detection tank, the total resistance The detection groove opening upward can facilitate the collection of liquid. In addition, other parts of the detection circuit in the present invention can be existing comparison circuits or amplifier circuits.

[0037] like Figure 1 As shown, the data acquisition module obtains the resistance value of the detection circuit set in the charging gun at continuous moments, and obtains the temperature value inside the gun at continuous moments collected by the temperature sensor in the charging gun;

[0038] a resistance abnormality judgment module, which judges whether the resistance value obtained at the current moment is equal to the resistance value obtained at the initial moment, and outputs a leakage instruction if the resistance value obtained at the current moment is less than the resistance value obtained at the initial moment, and outputs a normal instruction if the resistance value obtained at the current moment is equal to the resistance value obtained at the initial moment, wherein the initial moment refers to the resistance value when the detection circuit is initially installed in the gun body (1) or the resistance value when the internal part is ensured to be dry and without leakage;

[0039] The leakage source comparison module, after confirming that there is a resistance anomaly, when there is a leakage in the corresponding gun, retrieves the cold source information preset in the system and passes through the liquid cooling pipe, and determines whether the cold source type in the cold source information is water. The cold source types used for liquid cooling include water or ethylene glycol, etc.;

[0040] The leakage analysis selection module adopts different analysis strategies according to the results of the leakage source comparison module. When the cooling source type is water, it determines whether the resistance value in the preset time period has recovered to the resistance value obtained at the initial time according to the temperature value in the gun obtained at the current moment, and outputs the leakage in the gun or external penetration according to the comparison result. Specifically, under normal circumstances, the amount of water vapor that penetrates from the outside into the gun body (1) when condensed into water droplets is relatively small, while the amount of leakage from the internal liquid cooling pipe is relatively large. Therefore, assuming that the preset time is - , the temperature inside the gun is 70°, so the charging gun - After a certain time, under the influence of the temperature inside the gun, a small amount of water on the internal detection circuit will be evaporated, and the resistance will return to , it can be considered as external penetration. When the amount of water inside is large and the evaporation speed is slow or not evaporated, the resistance at this time does not return to , it can be determined that there is leakage in the gun.

[0041] The method also includes a resistance change model construction step, in which the leakage liquid conductivity and the leakage liquid evaporation rate in the cold source information obtained in the leakage liquid source comparison module are integrated, wherein the leakage liquid evaporation rate data at different temperatures and the leakage liquid conductivity of the cold zone liquid with different components and concentrations are obtained based on historical data or simulation. Of course, the leakage liquid evaporation rate and the leakage liquid conductivity in the present invention are both existing data, and the temperature value in the gun, the leakage liquid conductivity and the leakage liquid evaporation rate are cleaned and integrated to obtain a data set;

[0042] Fit the relationship between the temperature and resistance in the gun. The change of leakage conductivity and evaporation rate over time is considered through the integral part. The exponential function is used for simulation. The integrated temperature resistance algorithm is configured as follows:

[0043] ,

[0044] in, is the temperature inside the gun, is the leakage conductivity, is the evaporation rate of the leaked liquid at the temperature inside the gun, For time, To detect the change in resistance in the circuit;

[0045] The sorted data set is divided into training set, test set and validation set in a ratio of 7:2:1. The training set and test set are substituted into the constructed temperature resistance algorithm to obtain the resistance change model, and then the resistance change model is verified and optimized by the validation set.

[0046] When the cold source type is not water, the temperature value in the gun obtained at the current moment is substituted into the preset resistance change model to output the cold source resistance change and the water resistance change. Then the actual resistance change within a certain moment when the temperature in the gun remains unchanged is analyzed and compared with the cold source resistance change and the water resistance change. According to the comparison result, the leakage in the gun or the external penetration is output. Specifically, when the cold source type is different, the corresponding conductivity is different, and the evaporation or evaporation rate of the cold source at the same temperature is different, which has different effects on the resistance. Assuming that the temperature value in the gun is 70°, the temperature value 70° in the gun is substituted into the preset resistance change model and output Change of cold source resistance within a moment and water resistance change , and then calculate the charging gun at a gun temperature of 70° After the time, the actual resistance change in the detection circuit ,like , it is judged as leakage inside the gun. , it is judged as external penetration.

[0047] The leakage control module immediately controls the charging gun to cut off the power when the comparison result is leakage inside the gun. When the comparison result is external penetration, the charging gun is controlled to ignore it and continue charging normally. The temperature inside the gun is regulated by air cooling to dry the inside of the gun. At the same time, the module will also record and store relevant abnormal information for subsequent analysis and processing.

[0048] The present invention has the advantage of analyzing the change in resistance through a detection circuit arranged in the gun body (1), and analyzing according to the type of cold source in the liquid cooling tube, selecting a corresponding analysis strategy, so that when the cold source is water or not water, it can be analyzed to determine whether it is liquid cooling tube leakage or external water vapor penetration, and matching a corresponding control strategy according to the source of the leakage, so that when the charging gun is plugged into the vehicle body for charging, it can detect whether there is leakage in the gun, and ensure that the charging gun can continue to charge in a safe condition.

[0049] Since the safety requirements of the charging gun are high, but if the power is cut off decisively based on a single layer of network for leakage analysis, it is easy to make a misjudgment. Therefore, it is necessary to design a leakage verification module to verify the leakage in the gun body (1). First, the charging box has its own output system. Secondly, the data acquisition module is used to obtain the wind speed value of the air cooling input into the charging gun and the air inlet humidity value at the air inlet end, and the humidity value in the gun collected by the humidity sensor in the charging gun is obtained.

[0050] The leakage verification module uses the leakage instruction output from the resistance abnormality judgment module as a trigger condition, and calculates the dehumidification time value for the humidity value in the gun to reach the inlet humidity value through the dehumidification algorithm according to the wind speed value, the inlet humidity value, the humidity value in the gun, and the temperature value in the gun. The inlet humidity value is usually relatively low. When there is no leakage in the normal gun, the humidity value in the gun should be the inlet humidity value input by the air cooling. When there is leakage in the gun, the humidity in the gun will increase, and the humidity can also be reduced and balanced by air cooling, and then the dehumidification time value is compared with the preset time threshold (the preset time threshold and the preset time period are the same in length). - ) and verify the output of the leakage analysis selection module according to the comparison result, where the dehumidification algorithm is configured as:

[0051] First, define a drying rate function , describes the drying rate at different wind speeds and temperatures. It is a combination of exponential terms and linear terms to reflect the nonlinear effects of wind speed and temperature on the drying rate. Specifically:

[0052] ,

[0053] in, They are the first coefficient, the second coefficient and the third coefficient, which can be obtained by fitting. Considering the relationship between humidity change and time, the humidity change rate is proportional to the current humidity value and is affected by the drying rate. The differential equation is obtained:

[0054] ,

[0055] in, As the proportional constant, we can get the expression of humidity changing with time:

[0056] ,

[0057] ,

[0058] ,

[0059] in, is the dehumidification time value, is the wind speed value, is the humidity value in the gun, is the temperature inside the gun, is the inlet air humidity value, The range of the value is all positive real numbers, indicating the time required to reach the target humidity under different initial conditions and environmental parameters. Greater than the preset time threshold , the verification result is leakage in the gun. At this time, the verification result is compared with the result output by the leakage analysis selection module. If the two are inconsistent, the leakage analysis selection module is re-performed or a power-off command is issued directly and decisively, and the fault indicator light is on. When the dehumidification time value is Less than or equal to the preset time threshold If the verification result is external penetration, it will also be compared with the result output by the leakage analysis selection module.

[0060] The leakage verification module includes a leakage verification submodule, which is used to adjust the flow rate of the cold source in the liquid cooling tube. The flow rate of the cold source can be increased or reduced. When the flow rate is increased, if the liquid cooling tube leaks, the leakage amount will increase, the temperature value in the gun will decrease, and the humidity value in the gun will increase or remain unchanged. When the flow rate is reduced, if the liquid cooling tube leaks, the leakage amount will decrease, the temperature value in the gun will increase, and the humidity value in the gun will decrease or remain unchanged. The humidity value in the gun after adjusting the flow rate is obtained as the humidity value in the gun, and then the temperature value in the gun after adjusting the flow rate is obtained as the temperature value in the gun, and then the humidity value in the gun, the temperature value in the gun, the wind speed value and the inlet humidity value are calculated again through the dehumidification algorithm to obtain the dehumidification time verification value. , the dehumidification time verification value Dehumidification time value For comparison, assuming that the flow rate decreases, the humidity in the gun does not change much in a short time, while the temperature in the gun body (1) changes greatly. If the dehumidification time verification value Less than dehumidification time value , then the result of the secondary verification is external penetration, otherwise, the result of the secondary verification is leakage inside the gun.

[0061] Since the amount of external penetration is relatively small, it is still necessary to conduct safety detection on it, so it also includes a liquid leakage alarm module. When the secondary verification result output by the liquid leakage verification submodule is external penetration, the wind speed value in the air cooling is adjusted, and the difference between the inlet humidity value and the outlet humidity value before adjusting the wind speed is calculated as the first difference value, and the difference between the inlet humidity value and the outlet humidity value after adjusting the wind speed is calculated as the second difference value. The first difference value is compared with the second difference value. If the second difference value is greater than the first difference value, an instruction of excessive water vapor penetration is output, otherwise, a normal instruction is output;

[0062] When the leakage control module obtains the instruction of a large amount of water vapor penetration, the temperature inside the gun is controlled to reduce the liquid cooling flow rate at a safe temperature, and the temperature inside the gun is increased to evaporate the condensed water on the detection circuit, because the liquid cooling effect is better than the air cooling effect. The water vapor in the gun is quickly taken away by the increased wind speed.

[0063] The above are only preferred embodiments of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A charging gun leakage monitoring system, characterized by: include: The data acquisition module obtains the resistance value of the detection circuit set in the charging gun at continuous moments, and obtains the temperature value inside the gun at continuous moments collected by the temperature sensor in the charging gun; The resistance abnormality judgment module judges whether the resistance value obtained at the current moment is equal to the resistance value obtained at the initial moment, and outputs a leakage instruction or a normal instruction according to the judgment result; The leakage source comparison module, when the judgment result is a leakage instruction, retrieves the cold source information preset in the system and passes into the liquid cooling pipe, and judges whether the cold source type in the cold source information is water; The leakage analysis selection module, when the cold source type is water, determines whether the resistance value in the preset time period has recovered to the resistance value obtained at the initial moment according to the temperature value in the gun obtained at the current moment, and outputs the leakage in the gun or external penetration according to the judgment result; when the cold source type is not water, substitutes the temperature value in the gun obtained at the current moment into the preset resistance change model to output the cold source resistance change and the water resistance change, and then analyzes the actual resistance change within a certain moment when the temperature in the gun remains unchanged, and compares it with the cold source resistance change and the water resistance change, and outputs the leakage in the gun or external penetration according to the comparison result; The leakage control module controls the charging gun to cut off the power supply when the comparison result is leakage inside the gun, and controls the charging gun to ignore when the comparison result is external penetration; It also includes a resistance change model building module, which uses a temperature resistance algorithm to build a resistance change model using different gun internal temperature values ​​and cold source information, wherein the cold source information includes leakage liquid conductivity and leakage liquid evaporation rate, and the gun internal temperature value corresponds to the leakage liquid evaporation rate one by one; The temperature resistance algorithm is configured as follows: ， in, is the temperature inside the gun, is the leakage conductivity, is the evaporation rate of the leaked liquid at the temperature inside the gun, For time, To detect the change in resistance in the circuit.

2. According to claim 1, a charging gun leakage monitoring system is characterized in that: The data acquisition module acquires the wind speed value of the air cooling in the charging gun and the air inlet humidity value at the air inlet end, and acquires the humidity value inside the gun collected by the humidity sensor in the charging gun; It also includes a liquid leakage verification module, which uses the liquid leakage instruction output from the resistance abnormality judgment module as a trigger condition, calculates the dehumidification time value for the humidity value in the gun to reach the inlet humidity value through a dehumidification algorithm according to the wind speed value, the inlet humidity value, the humidity value in the gun, and the temperature value in the gun, and then compares the dehumidification time value with a preset time threshold, and verifies the result output by the liquid leakage analysis selection module according to the comparison result; The dehumidification algorithm is configured as follows: ， ， ， in, is the dehumidification time value, is the wind speed value, is the humidity value in the gun, is the temperature inside the gun, is the inlet air humidity value, is the proportionality constant, They are the first coefficient, the second coefficient and the third coefficient respectively.

3. According to claim 2, a charging gun leakage monitoring system is characterized in that: The liquid leakage verification module includes a liquid leakage verification submodule, The liquid leakage verification submodule adjusts the flow rate of the cold source in the liquid cooling tube, and obtains the humidity value in the gun after adjusting the flow rate as the humidity control value in the gun, and then obtains the temperature value in the gun after adjusting the flow rate as the temperature control value in the gun, and then calculates the humidity value in the gun, the temperature value in the gun, the wind speed value and the inlet humidity value through the dehumidification algorithm again to obtain the dehumidification time verification value, and compares the dehumidification time verification value with the dehumidification time value, and performs a second verification on the verification result output by the liquid leakage verification module according to the comparison result.

4. A charging gun leakage monitoring system according to claim 3, characterized in that: It also includes a liquid leakage alarm module, when the secondary verification result output by the liquid leakage verification submodule is external penetration, the wind speed value in the air cooling is adjusted, the difference between the inlet humidity value and the outlet humidity value before the wind speed is adjusted is calculated as a first difference value, and the difference between the inlet humidity value and the outlet humidity value after the wind speed is adjusted is calculated as a second difference value, the first difference value is compared with the second difference value, if the second difference value is greater than the first difference value, then an instruction of excessive water vapor penetration is output, otherwise, a normal instruction is output; When the leakage control module obtains the instruction of a large amount of water vapor penetration, it controls the charging gun to increase the wind speed and controls the temperature inside the gun to reduce the liquid cooling flow rate at a safe temperature.

5. A charging gun leakage monitoring system according to claim 4, characterized in that: The duration of the preset time period is the same as the preset time-consuming threshold.

6. A charging gun, comprising a gun body (1), characterized in that: A detection chip (2) is provided in the gun body (1), a detection circuit and an actuator are configured in the detection chip (2), and a liquid leakage monitoring system according to any one of claims 1 to 5 is configured in the actuator.

7. A charging gun according to claim 6, characterized in that: The detection chip (2) is arranged on the inner wall of the gun body (1), and a plurality of detection slots with notches facing upward are provided on the detection chip (2). The detection circuit comprises an impedance detection unit, and the impedance detection unit comprises a plurality of detection resistors arranged in series. The detection resistors are arranged in the detection slots, and each detection resistor is arranged corresponding to a detection slot.

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