Method and apparatus for temperature-based compensation for DC charging docks

Abstract

The present invention discloses a method and apparatus for temperature-based compensation of a DC charging dock, in which the method includes: collecting the temperature of a terminal of a DC charging dock, calculating the coefficients of a temperature compensation function corresponding to different current values, and obtaining a corrected temperature according to the collected temperature of the terminal of the DC charging dock, the coefficients of the temperature compensation function corresponding to different current values, and the pre-established temperature compensation function, which is sent to a charging controller of an electric vehicle. The present invention can realize the compensation of the temperature error caused by the delay of temperature transmission during charging of an electric vehicle, and realize the safe, accurate and fast charging of the vehicle.

Description

Related Applications

[0001] This application claims priority to a Chinese patent application filed on July 23, 2021, bearing application number 202110839832.2 and entitled "Method and apparatus for temperature-based compensation for DC charging dock," the entire contents of which are incorporated herein in their entirety. [Technical Field]

[0002] The present invention relates to the technical field of DC charging for electric vehicles, and in particular to a method and apparatus for temperature-based compensation for DC charging docks. [Background technology]

[0003] This section is intended to provide a background or context for the claimed embodiments of the invention. Nothing herein should be considered prior art by virtue of its inclusion in this section.

[0004] With the development of new energy vehicles, how to safely, accurately, and quickly charge the vehicle terminals has become a new market requirement. However, currently, during charging, temperature errors occur due to delays in temperature transmission, that is, the collected temperature of the terminals of the DC charging dock is inaccurate, so that safe, accurate, and fast charging of electric vehicles cannot be ensured. Summary of the Invention

[0005] An embodiment of the present invention provides a temperature-based compensation method for a DC charging dock to compensate for temperature errors caused by delays in temperature transmission, the method comprising: Collecting the temperature of the terminals of the DC charging dock; Calculating coefficients of a temperature compensation function corresponding to different current values; and obtaining a corrected temperature, which is sent to a charging controller of the electric vehicle, based on the collected temperatures of the terminals of the DC charging dock, coefficients of a temperature compensation function corresponding to different current values, and a pre-established temperature compensation function.

[0006] An embodiment of the present invention is a temperature-based compensation device for a DC charging dock for compensating for temperature errors caused by delays in temperature transmission, the device comprising: a temperature collection unit for collecting the temperature of the terminals of the DC charging dock; a coefficient calculation unit for calculating coefficients of a temperature compensation function corresponding to different current values; and a compensation unit for obtaining a corrected temperature, which is sent to a charging controller of the electric vehicle, based on the collected temperatures of the terminals of the DC charging dock, coefficients of a temperature compensation function corresponding to different current values, and the pre-established temperature compensation function.

[0007] An embodiment of the present invention further provides a computer device including a memory, a processor, and a computer program stored in the memory and executable by the processor, wherein when the computer program is executed by the processor, the above-mentioned method for temperature-based compensation for a DC charging dock is realized.

[0008] An embodiment of the present invention further provides a computer-readable storage medium having stored thereon a computer program for causing the above-described method for temperature-based compensation for a DC charging dock to be performed.

[0009] In an embodiment of the present invention, compared to the technical solution of the prior art, which causes temperature errors due to delays in temperature transmission during charging, i.e., the collected terminal temperatures of the DC charging dock are inaccurate, and therefore cannot ensure safe, accurate, and fast charging of the electric vehicle, the technical solution of temperature-based compensation for the DC charging dock collects the terminal temperatures of the DC charging dock, calculates the coefficients of a temperature compensation function corresponding to different current values, and obtains the corrected temperature based on the collected terminal temperatures of the DC charging dock, the coefficients of the temperature compensation function corresponding to different current values, and the pre-established temperature compensation function, which is sent to the charging controller of the electric vehicle, thereby compensating for the temperature errors due to delays in temperature transmission during charging of the electric vehicle, and realizing safe, accurate, and fast charging of the vehicle. [Brief explanation of the drawings]

[0010] The drawings described herein are intended to provide a further understanding of the invention and constitute a part of this application, but are not to be construed as limiting the invention. [Figure 1] 4 is a schematic diagram of the delay and variation in phase and amplitude of the temperature measured by the temperature sensor and the actual temperature of the terminal in an embodiment of the present invention. FIG. [Figure 2] FIG. 2 is a flow diagram of a method for temperature-based compensation of a DC charging dock in an embodiment of the present invention. [Figure 3] FIG. 2 is a schematic diagram of the temperature compensation principle of the DC charging dock in an embodiment of the present invention. [Figure 4] FIG. 10 is a flow diagram of a method for temperature-based compensation of a DC charging dock in another embodiment of the present invention. [Figure 5] FIG. 10 is a schematic diagram showing coefficient values ​​determined by fitting with MATLAB (registered trademark) when the charging current is 200 A in an embodiment of the present invention. [Figure 6] 1 is a structural schematic diagram of a temperature compensation device for a DC charging dock according to an embodiment of the present invention; [Figure 7] 2 is a structural schematic diagram of a temperature collection unit according to an embodiment of the present invention; FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention clearer and easier to understand, the embodiments of the present invention will be described in more detail below with reference to the drawings, wherein the schematic embodiments of the present invention and their descriptions are for the purpose of interpreting the present invention but are not intended to limit the present invention.

[0012] The inventor discovered a technical problem in a DC charging dock: the temperature sensor needs to measure the temperature of the white terminal, but the temperature sensor is very close to the terminal but is not directly attached to the surface of the terminal, which causes delays and losses in the transmission of the temperature of the terminal to the temperature sensor. As shown in Figure 1, there are delays and variations in both phase and amplitude between the temperature measured by the temperature sensor and the actual temperature measured on the surface of the terminal.

[0013] In consideration of the above technical problems, the inventor has proposed a technical solution for temperature-based compensation of DC charging docks, which adjusts and compensates for the temperature error caused by the delay in temperature transmission during charging, and ensures safe, accurate and fast charging of electric vehicles. The following will introduce the technical solution for temperature-based compensation of DC charging docks in detail as follows:

[0014] FIG. 2 is a flow diagram of a method for temperature-based compensation of a DC charging dock in an embodiment of the present invention. As shown in FIG. 2, the method includes the following steps:

[0015] Step 101: Collect the temperature of the terminals of the DC charging dock.

[0016] Step 102: Calculate the coefficients of the temperature compensation function corresponding to different current values.

[0017] Step 103: According to the collected terminal temperatures of the DC charging dock, the coefficients of the temperature compensation function corresponding to different current values, and the pre-established temperature compensation function, obtain a corrected temperature to be sent to the charging controller of the electric vehicle.

[0018] The temperature-based compensation method for a DC charging dock according to an embodiment of the present invention uses software differential and hysteresis compensation to adjust for temperature errors caused by temperature transmission and losses, ensuring that the corrected temperature is accurate and reliable, thereby achieving safe, accurate, and fast charging of the vehicle. Each step of the method will now be described in detail with reference to Figures 3 to 7.

[0019] As shown in Figure 3, the temperature treatment process mainly includes three parts: (1) temperature collection, (2) calculation of the coefficient ATs of the temperature compensation function according to the current value, and (3) determination of the delay (temperature) compensation function. The details are introduced as follows:

[0020] (1) Temperature collection, i.e., detailed implementation of step 101 above: The temperature of the DC charging dock terminal collected in this embodiment of the present invention is separated and amplified by a temperature sensor and a voltage divider resistor, resulting in different voltages. These are input into a single-chip microcomputer (temperature correction unit, i.e., a compensation unit described below), and a table lookup (relationship between voltage and temperature) can be used to obtain the temperature value S corresponding to the temperature sensor voltage. The block diagram of the hardware circuit (temperature collection circuit) is shown in Figure 7. The advantage of separating and amplifying the temperature signal using a temperature sensor and a voltage divider resistor to produce different voltages is that it can isolate interference from the previous signal and convert the resistance signal into a voltage signal that is easy for the single-chip microcomputer to collect, further improving the safety and accuracy of charging.

[0021] As can be seen from the above, in one embodiment, collecting the temperature of the terminals of the DC charging dock may include collecting the temperature of the terminals of the DC charging dock by a temperature collection unit.

[0022] The temperature collection unit A voltage dividing resistor whose first end is connected to the 5V voltage end after converting the 12V voltage at the vehicle end; a temperature sensor, the first end of which is connected to the second end of the voltage dividing resistor and the second end of which is grounded, for collecting a voltage signal at a terminal of the DC charging dock; a temperature collecting circuit, the input terminal of which is connected to the first terminal of the temperature sensor, for separating the voltage signal collected by the temperature sensor and obtaining a separated voltage; a voltage divider circuit having an input connected to the output of the temperature collecting circuit for converting the separated voltage into an effective voltage signal that is easy to collect; The useful voltage signal that is easy to collect is used to determine the temperature value corresponding to the voltage collected by the temperature sensor as the temperature of the terminals of the DC charging dock based on the pre-established relationship between voltage and temperature.

[0023] In practical implementation, the temperature obtained using the temperature collection unit is more accurate, which further improves the accuracy and safety of the temperature compensation of the DC charging dock.

[0024] (2) Calculation of the compensation function coefficient ATs according to the current value: The current range of the charging dock terminal is 100A-500A. For different currents, the square of the current is directly proportional to the temperature rise. Using the differential method, the current value is directly proportional to the temperature differential, and ATs ultimately corresponds to the temperature rise rate. However, since the temperature rise rate corresponding to different current stages during calibration is nonlinear, the currents calculated for different temperature rise rates after subsequent stepping have different K and B. Furthermore, the K and B corresponding to the ATs calculated according to different currents are also different. The advantage of making the current value directly proportional to the temperature differential is as follows: When the external conditions do not change, it is determined that the current value and the temperature rise rate have a linear relationship, and the temperature differential value = temperature difference value / time difference value, where the temperature differential value corresponds to the temperature rise slope (temperature rise rate, temperature change rate) within a certain time period. By actually measuring the temperature rise slope K1 at 100A and the slope K2 at 500A, the different current values ​​ya corresponding to the different temperature rise slopes x are calculated using the linear equation y=KKx+bb, where KK=(500-100) / (k2-k1), bb is a constant, y is the current value ya corresponding to the different temperature rise slopes, and ATs is a coefficient obtained by fitting the temperature curve corresponding to the actual fixed charging current to the standard temperature using MATLAB®. When the current is set to 500A, the corresponding ATs is ATs-500, and when the current is set to 100A, the corresponding ATs is ATs-100. Thus, the ATs for delay compensation at different currents ya are determined by the corresponding relationship: ATs = ya × K + b, where K = ((ATs-500)-(ATs-100)) / (500-100), ATs is the coefficient of the temperature compensation function, ya is the current value, and K and b are constants determined by actual measurement. For accurate measurement, different coefficients K and b are calculated using the same formula for overcurrents of 500A-700A and the lower operating current of 50A-100A, and then modified separately to obtain different ATs.

[0025] As can be seen from the above, in one embodiment, the step of calculating the coefficients of the temperature compensation function corresponding to different current values ​​comprises: making the current value directly proportional to the derivative of the temperature, thereby determining different current values ​​corresponding to different rates of temperature rise; and determining coefficients of a temperature compensation function corresponding to different current values ​​based on different current values ​​corresponding to different rates of temperature rise.

[0026] As can be seen from the above, in one embodiment, calculating the coefficients of the temperature compensation function corresponding to different current values ​​may include calculating the coefficients of the temperature compensation function corresponding to different current values ​​according to the following formula: ATs=ya×K+b Here, K=((ATs-500)-(ATs-100)) / (500-100), ATs is a coefficient of the temperature compensation function, ya is a current value, and K and b are constants.

[0027] As can be seen from the above, in one embodiment, different K and b may be determined according to the overcurrent range of 500A-700A and the lower operating current range of 50A-100A.

[0028] (3) Determining the Delay (Temperature) Compensation Function: During testing, temperature is compensated for delays and losses in temperature transmission. The compensation equation is a first-order delay function: y2 = (1 + Ts × S) / (1 + ATS × S), where Ts is a constant, ATS is a variable proportional to the current during temperature rise, and S is the current sampled temperature value (the temperature of the DC charging dock terminals). Ts and ATS are coefficients obtained by fitting a temperature curve corresponding to a fixed actual charging current to a standard temperature using MATLAB®. By fixing the parameter Ts, different ATS values ​​are obtained corresponding to different currents. Different ATS values ​​are called for corresponding to different temperature change rates in the delay compensation calculation. Figure 5 shows a schematic diagram of the coefficient values ​​determined by fitting using MATLAB® when the charging current is 200A.

[0029] (4) The overall temperature correction flowchart is shown in Figure 4. The temperature-corrected value (corrected temperature) is sent to the vehicle's charging controller CCU via the CAN line, and the vehicle's charging controller CCU can use this corrected temperature to safely, accurately, and quickly charge the electric vehicle.

[0030] In a specific implementation, once the sampled temperature, the temperature compensation function, and the coefficients of the temperature compensation function are determined, a temperature correction equation can be used to determine the final corrected temperature that is sent to the electric vehicle charge controller.

[0031] As described above, the embodiment of the present invention can stably and quickly charge a vehicle, and is simple, fast, and practical by correcting errors through software, i.e., correcting sampled temperature values ​​at different currents through software differentiation and hysteresis correction.

[0032] A beneficial technical effect of embodiments of the present invention is that the temperature-based compensation method for a DC charging dock according to embodiments of the present invention can compensate for temperature errors caused by delays in temperature transmission during charging of an electric vehicle, thereby realizing safe, accurate, and fast charging of the vehicle.

[0033] In an embodiment of the present invention, a temperature-based compensation device for a DC charging dock is further provided, as described in the following embodiment. The principle of the device's solution is similar to that of the temperature-based compensation method for a DC charging dock, so the implementation of the device may refer to the implementation of the temperature-based compensation method for a DC charging dock, and no further description will be repeated.

[0034] FIG. 6 is a structural schematic diagram of a temperature compensation device for a DC charging dock according to an embodiment of the present invention, which includes: a temperature collection unit 01 for collecting the temperature of the terminals of the DC charging dock; a coefficient calculation unit 02 for calculating coefficients of a temperature compensation function corresponding to different current values; and a compensation unit 03 for obtaining a corrected temperature based on the collected terminal temperatures of the DC charging dock, the coefficients of the temperature compensation function corresponding to different current values, and the pre-established temperature compensation function, which is sent to the charging controller of the electric vehicle.

[0035] In one embodiment, as shown in FIG. 7, the temperature collection unit comprises: A voltage dividing resistor whose first end is connected to the 5V voltage end after converting the 12V voltage at the vehicle end; a temperature sensor having a first end connected to the second end of the voltage dividing resistor and a second end grounded, for collecting a voltage signal at a terminal of the DC charging dock; a temperature collecting circuit, the input terminal of which is connected to the first terminal of the temperature sensor, for separating the voltage signal collected by the temperature sensor and obtaining a separated voltage; a voltage divider circuit having an input connected to the output of the temperature collecting circuit for converting the separated voltage into an effective voltage signal that is easy to collect; The useful voltage signal that is easy to collect is used to determine the temperature value corresponding to the voltage collected by the temperature sensor as the temperature of the terminals of the DC charging dock based on the pre-established relationship between voltage and temperature.

[0036] In one embodiment, the coefficient calculation unit specifically comprises: The current value is made directly proportional to the differential value of the temperature, and different current values ​​corresponding to different rates of temperature rise are obtained; The coefficients of the temperature compensation function corresponding to different current values ​​may be determined based on different current values ​​corresponding to different temperature rise rates.

[0037] In one embodiment, the coefficient calculation unit may be specifically used to calculate the coefficients of the temperature compensation function corresponding to different current values ​​according to the following formula: ATs=ya×K+b where ATs is a coefficient of the temperature compensation function, ya is a current value, and K and b are constants.

[0038] In one embodiment, the overcurrent range may be determined according to 500A-700A and the lower operating current range of 50A-100A.

[0039] An embodiment of the present invention further provides a computer device including a memory, a processor, and a computer program stored in the memory and executable by the processor, wherein when the computer program is executed by the processor, the above-mentioned method for temperature-based compensation for a DC charging dock is realized.

[0040] An embodiment of the present invention further provides a computer-readable storage medium having stored thereon a computer program for causing the above-described method for temperature-based compensation for a DC charging dock to be performed.

[0041] In an embodiment of the present invention, compared to the technical solution of the prior art, which causes temperature errors due to delays in temperature transmission during charging, i.e., the collected terminal temperatures of the DC charging dock are inaccurate, and therefore cannot ensure safe, accurate, and fast charging of the electric vehicle, the technical solution of temperature-based compensation for the DC charging dock collects the terminal temperatures of the DC charging dock, calculates the coefficients of a temperature compensation function corresponding to different current values, and obtains the corrected temperature based on the collected terminal temperatures of the DC charging dock, the coefficients of the temperature compensation function corresponding to different current values, and the pre-established temperature compensation function, which is sent to the charging controller of the electric vehicle, thereby compensating for the temperature errors due to delays in temperature transmission during charging of the electric vehicle, and realizing safe, accurate, and fast charging of the vehicle.

[0042] It will be apparent to those skilled in the art that embodiments of the present invention may be provided as a method, a system, or a computer program product. Therefore, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product embodied in one or more computer-usable storage media (including, but not limited to, magnetic disk memory, CD-ROM, optical memory, etc.) containing computer-usable program code.

[0043] The present invention has been described with reference to flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or each block in the flowcharts and / or block diagrams, and combinations of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to create a machine, such that the instructions, executed by the processor of the computer or other programmable data processing device, create an apparatus for implementing the functions specified in one or more flows in the flowcharts and / or one or more blocks in the block diagrams.

[0044] These computer program instructions may be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, thereby creating an article of manufacture that includes a command apparatus that implements the functions specified in one or more flows of the flowcharts and / or one or more blocks of the block diagrams according to the instructions stored in the computer-readable memory.

[0045] These computer program instructions may be loaded into a computer or other programmable data processing device and cause the computer or other programmable device to execute a series of operations and steps to generate a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more flows of the flowcharts and / or one or more blocks of the block diagrams.

[0046] The specific embodiments described above have further explained the objectives, technical solutions and beneficial effects of the present invention in detail, but the above descriptions are merely specific embodiments of the present invention and do not limit the protection scope of the present invention. It should be understood that any modifications, equivalent substitutions, improvements, etc. made within the technical spirit and principles of the present invention should all be included in the protection scope of the present invention.

Claims

1. 1. A method of temperature-based compensation for a DC charging dock, comprising: Collecting the temperature of the terminals of the DC charging dock; calculating a coefficient of the temperature compensation function corresponding to the different current values ​​by making the current value directly proportional to the differential value of the temperature and determining a coefficient of the temperature compensation function corresponding to the different current values; obtaining a corrected temperature based on the collected temperature of the terminals of the DC charging dock, the calculated coefficients of the temperature compensation function, and a pre-established temperature compensation function, the corrected temperature being sent to a charge controller of an electric vehicle; 10. A method for temperature-based compensation for a DC charging dock, comprising:

2. Collecting the temperature of the terminals of the DC charging dock includes collecting the temperature of the terminals of the DC charging dock by a temperature collection unit; The temperature collection unit a voltage dividing resistor having a first end connected to a voltage end of the vehicle; a temperature sensor, the first end of which is connected to the second end of the voltage dividing resistor and the second end of which is grounded, for collecting a voltage signal at a terminal of the DC charging dock; a temperature collecting circuit, the input terminal of which is connected to the first terminal of the temperature sensor, for separating the voltage signal collected by the temperature sensor to obtain a separated voltage; a voltage divider circuit having an input connected to the output of the temperature collecting circuit for converting the separated voltage into an effective voltage signal; 2. The method for temperature-based compensation of a DC charging dock according to claim 1, wherein the effective voltage signal is used to determine a temperature value corresponding to the voltage sampled by the temperature sensor as the temperature of the terminals of the DC charging dock based on a pre-established relationship between voltage and temperature.

3. Calculating the coefficients of the temperature compensation function corresponding to the different current values ​​includes calculating the coefficients of the temperature compensation function corresponding to the different current values ​​according to the following formula: ATs = ya × K + b 3. The method of temperature-based compensation for a DC charging dock as claimed in claim 2, wherein ATs is a coefficient of a temperature compensation function, ya is a current value, and K and b are constants.

4. The method for temperature-based compensation of a DC charging dock as claimed in claim 3, wherein different K and b are obtained according to an overcurrent range of 500A-700A and a range below the operating current of 50A-100A.

5. a temperature collection unit for collecting the temperature of the terminals of the DC charging dock; a coefficient calculation unit for calculating coefficients of a temperature compensation function corresponding to different current values; a compensation unit for obtaining a corrected temperature, the corrected temperature being sent to a charging controller of an electric vehicle, based on the temperature of the terminal of the DC charging dock collected by the temperature collecting unit, the coefficients of a temperature compensation function corresponding to different current values ​​calculated by the coefficient calculating unit, and a pre-established temperature compensation function; The coefficient calculation unit is used to obtain different current values ​​corresponding to different temperature rise rates by making the current value directly proportional to the differential value of temperature, and determine the coefficients of the temperature compensation function corresponding to the obtained different current values ​​corresponding to the different temperature rise rates.

1. A temperature-based compensation device for a DC charging dock, comprising:

6. The temperature collection unit a voltage dividing resistor having a first end connected to a voltage end of the vehicle; a temperature sensor, the first end of which is connected to the second end of the voltage dividing resistor and the second end of which is grounded, for collecting a voltage signal at a terminal of the DC charging dock; a temperature collecting circuit, the input terminal of which is connected to the first terminal of the temperature sensor, for separating the voltage signal collected by the temperature sensor and obtaining a separated voltage; a voltage divider circuit having an input connected to the output of the temperature collecting circuit for converting the separated voltage into an effective voltage signal; 6. The temperature-based compensation device for a DC charging dock according to claim 5, wherein the effective voltage signal is used to determine a temperature value corresponding to the voltage sampled by the temperature sensor as the temperature of the terminals of the DC charging dock based on a pre-established relationship between voltage and temperature.

7. The coefficient calculation unit is used to calculate the coefficients of the temperature compensation function corresponding to different current values ​​according to the following formula: ATs = ya × K + b 6. The temperature-based compensation device for a DC charging dock as claimed in claim 5, wherein ATs is a coefficient of the temperature compensation function, ya is a current value, and K and b are constants.

8. The temperature-based compensation device for a DC charging dock as claimed in claim 7, wherein different K and b are obtained according to an overcurrent range of 500A-700A and a range below the operating current of 50A-100A.

9. A computing device including a memory, a processor, and a computer program stored in the memory and executable by the processor, A computer apparatus, characterized in that when the computer program is executed by the processor, the method according to any one of claims 1 to 4 is implemented.

10. A computer-readable storage medium having stored thereon a computer program for executing the method according to any one of claims 1 to 4.

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