A direct current charging gun over-temperature control method

Abstract

The application provides a direct current charging gun over-temperature control method, wherein the temperature of the charging gun detected in real time is uploaded to the background through monitoring, the real-time temperature data is processed by the background, the charging current of the charging pile is controlled, the temperature of the charging gun is controlled, and safe charging is realized. In the electric vehicle charging gun, a temperature sensor is arranged, the charging monitoring collects data, processes the data, and communicates with the background through a wireless communication module. The application provides control of safe charging of the charging pile by detecting the real-time temperature of the charging gun, fully utilizes the advantages of the Internet of Things and big data processing, and meets the requirements of users.

Description

Technical Field

[0001] This invention relates to a method for controlling over-temperature during charging of a DC charging gun. Background Technology

[0002] With the rapid development of new energy electric vehicles, the application of charging piles to support electric vehicle charging is becoming increasingly widespread. At the same time, car owners are placing increasingly higher demands on the charging speed of electric vehicles. With the continuous advancement of battery technology, batteries can now accept larger and larger charging currents. Accompanying the ever-growing market demand for high-power and ultra-fast charging, the charging piles on the market are now mainly high-power DC fast charging piles.

[0003] Charging of electric vehicle (EV) batteries is primarily achieved by connecting a charging station to the EV's charging interface via a charging gun. To ensure compatibility between different charging station manufacturers and vehicles from different automakers, the government has established a unified standard for charging interfaces. Charging guns designed based on this standard currently have a maximum charging current of 250A. However, due to the predominantly DC fast charging demand, charging guns often use much higher charging currents, almost reaching their maximum output. Since the charging gun is plugged into the EV's charging interface, power transfer occurs through the contact of copper male and female terminals. This terminal contact generates contact resistance. When this contact is compromised due to factors such as incomplete insertion or wear and tear on the terminals, the contact resistance increases, leading to overheating of the charging gun. This not only poses a safety hazard but can also result in a fire.

[0004] The industry has explored solutions to potential hazards caused by overheating of charging guns, achieving positive results. For example, Chinese invention patent application publication CN 109460087 A discloses an AC / DC integrated temperature-controlled charging device. This device detects the temperature on the charging guns of a charging station. It is used to charge vehicles and includes a charging station body and multiple charging guns mounted on the charging station body. These charging guns are divided into AC and DC charging guns, each containing at least one temperature sensor. The charging station body is activated by user operation. When a charging gun is plugged into the charging socket on the vehicle, the charging gun reports its charging gun type to the charging station body. Upon receiving the charging gun type, the charging station body communicates with the vehicle and controls the charging guns to charge the vehicle based on the communication result. The temperature of the charging gun during charging is obtained through the temperature sensors. When the temperature reaches a preset temperature corresponding to the charging gun type, the charging station body reduces the charging power of the charging gun to lower the temperature.

[0005] While this temperature-controlled charging device can monitor the temperature on the charging gun and control the charging current to prevent dangers caused by overheating, it cannot analyze the causes of overheating to guide users in eliminating potential faults. In the context of the Internet of Things and big data, it cannot meet users' requirements for smart charging piles. Summary of the Invention

[0006] This invention addresses the shortcomings of current temperature-controlled charging devices, which, while monitoring the temperature of the charging gun and controlling the charging current to prevent dangers caused by overheating, cannot analyze the causes of overheating and thus guide users to eliminate potential faults. In the context of the Internet of Things and big data, this invention provides a DC charging gun over-temperature control method.

[0007] The technical solution for achieving the technical objective of this invention is: a method for controlling over-temperature of a DC charging gun, wherein the charging pile includes at least two independent charging rectifier modules, and all the charging rectifier modules are connected in parallel to the charging gun; after the charging gun is inserted into the charging interface of the electric vehicle to be charged, the following steps are included;

[0008] Step 1: Report that the charging gun is properly connected to the charging port of the electric vehicle;

[0009] Step 2: Monitor the charging current required by the vehicle according to the instructions from the background system and charge the electric vehicle accordingly.

[0010] Step 3: Monitor the temperature of the charging gun and upload the temperature data to the backend;

[0011] Step 4: The background process analyzes the temperature data, including the following steps:

[0012] Step 401: The generated temperature curve is recorded and saved in the background and sent to the user for reference;

[0013] Step 402: Determine if the current temperature is normal. This step involves learning from the historical data of the charging gun and other charging guns of the same model used by the user. If the temperature is abnormal multiple times, a message will be sent to remind the user that the vehicle connector may have malfunctioned after multiple uses and needs to be repaired in time. If the temperature is abnormal only this time, proceed to step 403.

[0014] Step 403: Issue an instruction to the charging pile monitoring system to reduce the output current of the rectifier module. If the charging gun temperature gradually returns to normal after reducing the charging current, proceed to step 3. If the charging gun temperature continues to rise to the over-temperature protection point, stop charging and notify the user that charging of the electric vehicle has been stopped due to excessive temperature.

[0015] Furthermore, in the above-mentioned DC charging gun over-temperature control method: in step 1, the voltage signal of the connection between the charging gun and the charging interface of the electric vehicle is used to determine whether the connection is normal. If the connection is abnormal, charging cannot continue.

[0016] Furthermore, in the above-mentioned DC charging gun over-temperature control method: in step 2, the user submits a charging request by contacting the backend through a user terminal.

[0017] Furthermore, in the above-mentioned DC charging gun over-temperature control method: in step 402, the current abnormal temperature includes the temperature exceeding the threshold, the degree of temperature increase per unit time, and the abnormality in the comparison of the user's charging historical data.

[0018] Furthermore, in the above-mentioned DC charging gun over-temperature control method, the threshold of 100 degrees Celsius can be adjusted appropriately according to the specific usage environment requirements of the charging gun.

[0019] This invention provides a method to control the safe charging of charging piles by detecting the real-time temperature of the charging gun, making full use of the advantages of the Internet of Things and big data processing to meet user requirements.

[0020] The present invention will now be described in more detail with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] Appendix Figure 1 The image shows a prototype used in an embodiment of the present invention.

[0022] Appendix Figure 2 This is a flowchart illustrating the control principle of the present invention. Detailed Implementation

[0023] As attached Figure 1 , Figure 2 As shown in the diagram, this embodiment is an external structural drawing of an outdoor 120KW single-gun DC charging pile 101. The 120KW charging pile has an externally mounted DC charging gun 201 with a maximum charging current of 250A / 1000V. Internally, it contains four 30KW constant power charging modules 202 and a charging monitor 203. The charging monitor 203 is equipped with a 4G communication module, enabling real-time wireless transmission of data during the charging process to the charging control platform 401, i.e., the backend. The maximum charging current of the charging pile can reach 250A, and the gun over-temperature protection point is set to 100 degrees Celsius. A temperature sensor is installed on the charging gun to monitor its temperature in real time. Furthermore, under the control of the charging gun processor (i.e., the charging gun processing terminal), the data from the temperature sensor is collected, converted to analog (AD) signals, and then uploaded to the backend (charging control platform 401) via wireless communication.

[0024] The working principle of a DC charging gun over-temperature control method described in this embodiment is as follows:

[0025] The customer first unplugs the charging gun 201 from charging pile 101, then reliably inserts the charging gun 201 into the charging port of electric vehicle 301. Next, the customer scans a QR code using WeChat / Alipay / APP or other third-party software on their mobile phone to enter the charging state. This means the user is communicating with the backend via their user terminal, paying fees, and submitting a charging request. This involves informing the backend of the desired service, such as the charging current and charging capacity, which are uploaded to the charging control center. After charging is complete, the charging control center sends a bill to the user terminal, which then settles the bill. The charging gun 201 charges the electric vehicle 301 according to its requested voltage and current. When the requested current from electric vehicle 301 is high, such as 250A, the charging module 202 outputs 250A of current through the charging gun 201 to charge the electric vehicle 301. Throughout the charging process, the charging monitoring 203 monitors the temperature of the charging gun 201. Under normal circumstances, the temperature of the charging gun 201 remains below 80 degrees Celsius until the electric vehicle 301 is fully charged.

[0026] If, during the charging process, due to some abnormal reason (such as poor contact between the charging gun and the vehicle's connector or the charging gun not being fully inserted), the temperature of the charging gun 201 head rises too quickly, and the charging monitoring 203 detects that the temperature of the charging gun 201 reaches 90 degrees Celsius (10 degrees Celsius below the protection point (threshold) temperature), the charging monitoring 203 will control the charging module to reduce the output current to 70% of the required current, i.e., 175A. By reducing the charging current, the temperature of the charging gun 201 head will stop rising or even decrease, thus ensuring that the temperature of the charging gun 201 head can continue to charge within a very safe range. In this embodiment, a resistance detection device is included to measure the resistance between the charging gun and the charging interface of the electric vehicle after the charging gun is inserted into the charging interface of the electric vehicle to be charged.

[0027] When a serious contact failure occurs between the charging gun and the charging interface, and reducing the charging current fails to prevent the temperature of the charging gun 201 from continuing to rise, the charging monitoring 203 will issue a command to the charging module 202 to immediately stop working and cease outputting charging current when the temperature of the charging gun 201 reaches 100 degrees Celsius. This ensures the safety of the charging pile and the electric vehicle, preventing any safety accidents. The charging gun terminal also detects the resistance between the charging gun and the electric vehicle's charging interface using a resistance detection device and uploads this data to the backend. The backend can then process this big data to determine if there is poor contact or other faults.

[0028] Throughout the charging process, the charging monitor 202 continuously reports the temperature of the charging gun 201 to the charging control platform 401. The charging control platform 401 records the temperature throughout the charging process as a curve for subsequent traceability. Simultaneously, by monitoring abnormal temperature curves of electric vehicles during charging and filtering data from past charging events, the charging control platform 401 intelligently compares the user's past charging gun temperature data curves to assess the safety status of the user's vehicle and provides user-friendly alerts about vehicle malfunctions, eliminating potential charging safety hazards and improving the charging experience.

[0029] In this embodiment, the DC charging gun over-temperature control process is as follows:

[0030] Step 1: Report to the backend that the connection between the charging gun and the electric vehicle's charging interface is normal. The connection between the charging gun and the electric vehicle's charging interface is normal by measuring the resistance when the charging gun and the electric vehicle's charging interface are connected. If this resistance value is greater than the set threshold, the connection is abnormal, and the user is prompted to make improvements.

[0031] Step 2: According to the backend instructions, the charging monitor charges the electric vehicle according to the charging current required by the vehicle; the user submits a charging request by contacting the backend through the user terminal. The backend issues instructions according to the user's request and sets the charging current through the charging monitor.

[0032] Step 3: Monitor the temperature of the charging gun and upload the temperature data to the backend;

[0033] Step 4: The background process analyzes the temperature data, including the following steps:

[0034] Step 401: The generated temperature curve is recorded and saved in the background and sent to the user for reference;

[0035] Step 402: Determine if the current temperature is normal. This step involves learning from historical data of the charging gun or similar models. If the current temperature is abnormal, proceed to step 403. Abnormal temperatures include temperatures exceeding a threshold, temperature increases per unit time, and discrepancies in the user's historical charging data. The threshold is typically 100 degrees Celsius and can be adjusted appropriately. In this embodiment, if the temperature reaches 90 degrees Celsius before reaching the threshold, it is considered too high and requires processing, proceeding to step 403. Additionally, if the temperature rises by more than 20 degrees Celsius within one minute for two consecutive minutes, it is also considered abnormal and requires returning to step 403. Furthermore, learning from the charging gun's historical data can also help determine if the temperature is normal.

[0036] Step 403: Issue an instruction to the charging pile monitoring system to reduce the output current of the rectifier module. If the charging gun temperature gradually returns to normal after reducing the charging current, proceed to step 3. If the charging gun temperature continues to rise to the over-temperature protection point, notify the user that charging of the electric vehicle has been stopped due to excessive temperature.

[0037] In summary, this embodiment of the DC charging gun over-temperature control method reduces the likelihood of charging gun tripping and stopping during charging by derating the charging gun when its temperature is abnormally high during the charging process. Furthermore, by using big data filtering, the method can predict the vehicle's operating status and inform customers of any abnormal conditions in advance, thereby eliminating potential safety hazards during vehicle charging and improving user satisfaction with the charging experience, thus achieving the purpose of the invention.

Claims

1. A method for controlling over-temperature during charging of a DC charging gun, wherein the charging pile includes at least two independent charging rectifier modules, and all charging rectifier modules are connected in parallel to the charging gun; characterized in that: After the charging gun is inserted into the charging port of the electric vehicle to be charged, the following steps are included; Step 1: Report that the charging gun is properly connected to the charging port of the electric vehicle; Step 2: Monitor the charging current required by the vehicle according to the instructions from the background system and charge the electric vehicle accordingly. Step 3: Monitor the temperature of the charging gun and upload the temperature data to the backend; Step 4: The background process analyzes the temperature data, including the following steps: Step 401: The generated temperature curve is recorded and saved in the background and sent to the user for reference; Step 402: Determine if the current temperature is normal. This step involves learning from the historical data of the charging gun and other charging guns of the same model used by the user. If the temperature is abnormal multiple times, a message will be sent to remind the user that the vehicle connector may have malfunctioned after multiple uses and needs to be repaired in time. If the temperature is abnormal only this time, proceed to step 403. Step 403: Issue an instruction to the charging pile monitoring system to reduce the output current of the rectifier module. If the charging gun temperature gradually returns to normal after reducing the charging current, proceed to step 3. If the charging gun temperature continues to rise to the over-temperature protection point, stop charging and notify the user that charging of the electric vehicle has been stopped due to excessive temperature.

2. The DC charging gun over-temperature control method according to claim 1, characterized in that: In step 1, the voltage signal between the charging gun and the electric vehicle's charging interface is checked to determine if the connection is normal. If the connection is abnormal, charging cannot continue.

3. The DC charging gun over-temperature control method according to claim 1, characterized in that: In step 2, the user submits a charging request by contacting the backend through their user terminal.

4. The DC charging gun over-temperature control method according to claim 1, characterized in that: In step 402, abnormal current temperature includes temperature exceeding the threshold, temperature increase per unit time, and abnormal comparison of the user's charging history data.

5. The DC charging gun over-temperature control method according to claim 4, characterized in that: Threshold 100 degrees Celsius.

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