Method and device for protecting charging device from overheating, electric vehicle

Abstract

A method and device for over-temperature protection of a charging device, an electric vehicle (200), and a computer-readable storage medium are provided. The over-temperature protection method includes the steps of: acquiring charging parameters of the charging device during charging, the charging parameters including time and temperature, and the time and temperature have a corresponding relationship; predicting a temperature change trend of the charging device based on the charging parameters; and, if it is determined based on the temperature change trend that the highest predicted temperature will exceed a predetermined temperature threshold, limiting the charging current before the highest predicted temperature exceeds the predetermined temperature threshold. By predicting the temperature change trend of the charging device based on the charging parameters, it is possible to determine in advance whether the charging device is over-temperature during charging, and the charging current can be adjusted more quickly and effectively, which is safer and more reliable.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This disclosure is based on and claims priority to a Chinese patent application filed on December 30, 2021, bearing application number 202111649681.0, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to the technical field of charging over-temperature protection, and in particular to a charging device over-temperature protection method, a charging device over-temperature protection device, an electric vehicle, and a computer-readable storage medium. [Background technology]

[0003] As electric vehicles continue to develop, their charging power gradually increases, increasing the risk of ablation failure due to overheating of the charging vehicle's socket. A commonly used overheating protection measure for charging vehicle sockets is to place a temperature sensor on the internal terminals of the charging vehicle's socket and set a maximum allowable temperature limit (temperature threshold) for the terminals. When the terminal temperature reaches the upper limit, the vehicle reduces the charging current, thereby reducing the temperature of the charging vehicle's socket.

[0004] In the above technical solutions, setting the temperature threshold too high can cause the terminal temperature to exceed the heat resistance limit of the materials in the charging device, which can lead to irreversible degradation of the mechanical and electrical performance of the materials, causing permanent damage to the vehicle's equipment. Setting the temperature threshold for the charging port too low can result in frequent current limiting, lengthening charging times and reducing the user experience. Summary of the Invention

[0005] The present disclosure aims to at least partially solve one of the technical problems in the related art by providing a method for protecting a charging device from overheating, which can predict the temperature change trend of the charging device based on charging parameters, thereby determining in advance whether the charging device is overheated during charging, and adjusting the charging current more quickly and effectively, resulting in a safer and more reliable method.

[0006] The present disclosure provides an over-temperature protection device for a charging device.

[0007] The present disclosure provides an electric vehicle.

[0008] The present disclosure provides a computer-readable storage medium.

[0009] An over-temperature protection method for a charging device according to an embodiment of the first aspect of the present disclosure includes the steps of acquiring charging parameters of the charging device during charging, the charging parameters including time and temperature, where the time and temperature are in a corresponding relationship; predicting a temperature change trend of the charging device based on the charging parameters; and, if it is determined based on the temperature change trend that the highest predicted temperature will exceed a predetermined temperature threshold, limiting the charging current before the highest predicted temperature exceeds the predetermined temperature threshold.

[0010] The over-temperature protection method for a charging device according to an embodiment of the present disclosure first obtains charging parameters of the charging device during charging, then predicts the temperature change trend of the charging device based on the charging parameters, and finally, if it is determined based on the temperature change trend that the highest predicted temperature will exceed a predetermined temperature threshold, limits the charging current before the highest predicted temperature exceeds the predetermined temperature threshold. In this way, the method predicts the temperature change trend of the charging device based on the charging parameters, and can determine in advance whether the charging device will be over-temperature during charging, thereby adjusting the charging current more quickly and effectively, which is safer and more reliable.

[0011] In addition, the over-temperature protection method for a charging device according to the above-described embodiment of the present disclosure may further have the following additional technical features.

[0012] In one embodiment of the present disclosure, the step of predicting the temperature change trend of the charging device based on the charging parameters includes the steps of determining charging parameters and a fitting function for multiple sampling points, substituting the charging parameters of each sampling point into the fitting function to obtain each parameter in the fitting function, substituting the obtained parameters into the fitting function to obtain a temperature prediction model of the charging device, and predicting the temperature change trend of the charging device based on the charging parameters and the temperature prediction model.

[0013] In one embodiment of the present disclosure, the fitting function is expressed by the following formula: T=C0+C1t+C2t 2 +C3t 3 +…+C n-1 t n-1 Here, T represents the temperature of the charging device, t represents the charging time, and C0 to C n-1 represents each parameter of the fitting function, and n is the number of temperature sampling points.

[0014] In another embodiment of the present disclosure, the fitting function is expressed as:

number

[0015] In one embodiment of the present disclosure, limiting the charging current before the highest predicted temperature exceeds a predetermined temperature threshold includes limiting the charging current in a manner that adjusts the charging current in a stepwise manner, thereby bringing the highest predicted temperature within a predetermined temperature range.

[0016] In one embodiment of the present disclosure, the step of limiting the charging current by adjusting the charging current stepwise includes the steps of determining an initial current during charging, reducing the initial current by a predetermined step size to obtain a first current, and, when controlling the charging device to charge the equipment at the first current, obtaining charging parameters within a first predetermined time period, predicting a temperature change trend of the charging device based on the charging parameters within the first predetermined time period, obtaining an updated maximum predicted temperature, and, if the updated maximum predicted temperature exceeds an upper limit value of a predetermined temperature interval, continuing to reduce the first current by the predetermined step size until the updated maximum predicted temperature becomes equal to or less than the upper limit value of the predetermined temperature interval.

[0017] In one embodiment of the present disclosure, the step of limiting the charging current in a step-by-step manner further includes the steps of: when controlling the charging device to charge the device at a first current, if the updated predicted maximum temperature does not exceed the upper limit value of the predetermined temperature interval, further determining a relationship between the updated predicted maximum temperature and the lower limit value of the predetermined temperature interval; when controlling the charging device to charge the device at the second current, obtaining charging parameters within a second predetermined time period, predicting a temperature change trend of the charging device based on the charging parameters within the second predetermined time period, obtaining an updated predicted maximum temperature; when controlling the charging device to charge the device at the second current, if the updated predicted maximum temperature is still lower than the lower limit value of the predetermined temperature interval, applying the value of the second current to the first current until the updated predicted maximum temperature is equal to or greater than the lower limit value of the predetermined temperature interval, wherein the second current is greater than the first current and less than the initial current.

[0018] In one embodiment of the present disclosure, the step of limiting the charging current in a manner of gradually adjusting the charging current further includes, when controlling the charging device to charge the device with the second current, if the updated highest predicted temperature is greater than the upper limit value of the specified temperature range, assigning the value of the second current to the initial current until the updated highest predicted temperature becomes equal to or less than the upper limit value of the specified temperature range.

[0019] In one embodiment of the present disclosure, determining the second current based on the initial current and the first current includes adding the initial current and the first current and then dividing the result in half to obtain the second current.

[0020] In one embodiment of the present disclosure, the step of limiting the charging current by gradually adjusting the charging current further includes, when controlling the charging device to charge the device with the second current, maintaining the current charging current if the updated highest predicted temperature is within a predetermined temperature range.

[0021] In one embodiment of the present disclosure, the step of limiting the charging current by gradually adjusting the charging current further includes, when controlling the charging device to charge the device with a first current, maintaining the current charging current if the updated highest predicted temperature is within a predetermined temperature range.

[0022] An over-temperature protection device for a charging device according to an embodiment of the second aspect of the present disclosure includes an acquisition module, a prediction module, and a protection control module, wherein the acquisition module acquires charging parameters of the charging device during charging, the charging parameters including time and temperature, the time and temperature being in a corresponding relationship, the prediction module predicts a temperature change trend of the charging device based on the charging parameters, and when the protection control module determines based on the temperature change trend that the highest predicted temperature will exceed a predetermined temperature threshold, it limits the charging current before the highest predicted temperature exceeds the predetermined temperature threshold.

[0023] In an embodiment of the present disclosure, an over-temperature protection device for a charging device uses an acquisition module to acquire charging parameters of the charging device during charging, a prediction module to predict the temperature change trend of the charging device based on the charging parameters, and a protection control module to determine, based on the temperature change trend, that the highest predicted temperature will exceed a predetermined temperature threshold, and then limit the charging current before the highest predicted temperature exceeds the predetermined temperature threshold. In this way, by predicting the temperature change trend of the charging device based on the charging parameters, the device can determine in advance whether the charging device will be overheated during charging, and can adjust the charging current more quickly and effectively, resulting in greater safety and reliability.

[0024] An electric vehicle according to an embodiment of the third aspect of the present disclosure includes a memory, a processor, and an overtemperature protection program for a charging device stored in the memory and executable by the processor, and when the processor executes the overtemperature protection program, the electric vehicle realizes the overtemperature protection method for the charging device.

[0025] The electric vehicle according to the embodiment of the present disclosure is based on the charging device over-temperature protection method and predicts the temperature change trend of the charging device using charging parameters, thereby determining in advance whether the charging device is over-temperature during charging, and adjusting the charging current more quickly and effectively, making it safer and more reliable.

[0026] A computer-readable storage medium according to an embodiment of the fourth aspect of the present disclosure stores an overtemperature protection program for a charging device, and when the overtemperature protection program is executed by a processor, it realizes the overtemperature protection method for the charging device.

[0027] The computer-readable storage medium according to an embodiment of the present disclosure is based on the above-mentioned charging device over-temperature protection method, and can predict the temperature change trend of the charging device according to charging parameters, thereby determining in advance whether the charging device is over-temperature during charging, and can adjust the charging current more quickly and effectively, which is safer and more reliable.

[0028] Additional aspects and advantages of the disclosure will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the disclosure. [Brief explanation of the drawings]

[0029] [Figure 1] 4 is a flowchart of an over-temperature protection method for a charging device according to an embodiment of the present disclosure. [Figure 2] 1 is a schematic structural diagram of a terminal of a charging device according to an embodiment of the present disclosure and a mating terminal of another charging device. [Figure 3]4 is a flowchart of an over-temperature protection method for a charging device according to one specific embodiment of the present disclosure. [Figure 4] 1 is a flowchart illustrating stepwise control of charging current according to one specific embodiment of the present disclosure. [Figure 5] 1 is a schematic block diagram of an over-temperature protection device for a charging device according to an embodiment of the present disclosure. [Figure 6] 1 is a schematic block diagram of an electric vehicle according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0030]

[0023] The following detailed description of the embodiments of the present disclosure will be given. Examples of the described embodiments are shown in the drawings, and the same or similar reference numerals throughout represent the same or similar parts, or parts having the same or similar functions. The embodiments described below with reference to the drawings are illustrative and are intended to help interpret the present disclosure, but should not be understood as limiting the present disclosure.

[0031] Hereinafter, a charging device over-temperature protection method, a charging device over-temperature protection device, an electric vehicle, and a computer-readable storage medium according to embodiments of the present disclosure will be described with reference to the drawings.

[0032] 1 is a flowchart of an over-temperature protection method for a charging device according to an embodiment of the present disclosure. The charging device can be applied to devices that require charging operations, such as electric vehicles and electrically powered vehicles.

[0033] As shown in FIG. 1, the over-temperature protection method for a charging device according to an embodiment of the present disclosure includes the following steps S1 to S3.

[0034] In S1, the charging parameters of the charging device during charging are obtained, and the charging parameters include time and temperature, and the time and the temperature have a corresponding relationship.

[0035] Specifically, a temperature sensor attached to the terminal of the charging device can collect the real-time temperature of the terminal as the temperature in the charging parameters of the charging device. That is, after charging begins, the terminal temperature corresponding to that time point is recorded as the charging parameter. For example, a collection period can be set in advance. When charging begins, the charging time is recorded as 0, and the current temperature is collected. During sampling, the terminal temperature T and the corresponding sampling time t are collected in sequence for each sampling period, and the charging parameter is recorded as (t, T). In this way, multiple charging parameters during charging are obtained.

[0036] The number of charging parameters and the sampling period can be set according to the actual situation.

[0037] In S2, the temperature change tendency of the charging device is predicted based on the charging parameters.

[0038] Specifically, the structure of the terminal of the charging device and the terminal of the other charging device that is paired with it is as shown in Figure 1. 2 As shown in Fig. 1, the heat generation rate of the high voltage terminal in the charging device is I 2 where R is the charging current, I is the charging current, and R is the connection resistance of the terminal. The connection resistance includes the connection resistance at the cable crimping position (i.e., crimping position A4 and crimping position B6 of cable 1) and the connection resistance at the lead butting portion 5 (i.e., the butting portion of jack 2 and pin 3). During the entire charging process, the heat generation rate and heat dissipation rate of the terminal of the charging device have the following relationship: CmΔτ=I 2 R-(φ1+φ2+φ3) where C is the specific heat capacity of the terminal, m is the mass of the terminal, Δτ is the temperature rise rate of the terminal, and φ1, φ2, and φ3 are the conductive heat dissipation rate, convective heat dissipation rate, and radiative heat dissipation rate, respectively.

[0039] When charging begins, the difference between the terminal temperature and the ambient temperature is small, so the heat dissipation rate (φ1 + φ2 + φ3) < the heat generation rate (I 2R). As can be seen from the above equation, when the specific heat capacity C and mass m are determined, the rate of temperature rise Δτ reaches its maximum value when charging begins. As time passes, the temperature of the terminals continues to rise, the heat dissipation rate gradually approaches the heat generation rate, and the rate of temperature rise Δτ also continues to decrease. When the temperature of the terminals rises until the heat generation rate and heat dissipation rate are equal, the rate of temperature rise becomes 0, after which the temperature no longer rises and a temperature equilibrium state is reached.

[0040] As can be seen from the above analysis, the initial slope of the time-temperature rise curve during charging of the terminal is a certain value Z (Z>0), and the slope continues to decrease as the charging time t increases, and at a certain point t0 In this case, the slope Z=0 and the terminal temperature T converges to a specific value T0.

[0041] The temperature-time relationship during charging of the charging device can be obtained by plotting multiple charging parameters obtained through testing on a coordinate system with time t on the horizontal axis and temperature T on the vertical axis, and then connecting these to obtain a corresponding temperature-time relationship curve to predict the temperature change trend of the charging device. Alternatively, the temperature change trend of the charging device can be predicted by constructing a temperature-time relationship equation. Because it is difficult to derive and analyze the relationship equation by analyzing the structure of the charging device, in this embodiment, the curve is fitted using the acquired charging parameters. That is, the acquired charging parameters (t, T) are substituted into a predetermined fitting function to construct a corresponding temperature-time relationship, and a time-temperature rise curve during charging of the charging device, i.e., the temperature-time change relationship, is obtained. The fitting function can be expressed as Taylor's equation, a least-squares fitting function, or the like. As can be seen, the curve described by fitting is merely an approximation of the original curve, but if there are a sufficient number of known points on the curve, the change law of the original curve can be more accurately described by fitting.

[0042] Since the above prediction is for the current charging process of the charging device, the predicted end time may be set to the end time of the charging process of the charging device, and the charging time of the charging device may be predicted based on the charging power or may be determined by querying the model number of the equipment to which the charging device is applied; the specific methods will not be described here.

[0043] A method for predicting the temperature change tendency during charging of a charging device by constructing a function will be described in detail below.

[0044] In one embodiment of the present disclosure, the step of fitting the temperature-time change relationship of the charging socket while the vehicle is being charged based on the temperature sampling time and temperature sampling value of each temperature sampling point includes the steps of determining charging parameters and a fitting function for multiple sampling points, substituting the charging parameters of each sampling point into the fitting function to obtain each parameter in the fitting function, substituting the obtained parameters into the fitting function to obtain a temperature prediction model of the charging device, and predicting the temperature change trend of the charging device based on the charging parameters and the temperature prediction model.

[0045] It should be noted that the number of sampling points must be equal to or greater than the number of parameters in the fitting function in order to solve for each unknown parameter in the fitting function.

[0046] In one embodiment of the present disclosure, the fitting function is expressed by the following formula: T=C0+C1t+C2t 2 +C3t 3 +…+C n-1 t n-1 (1) where T represents the temperature of the charging socket, t represents the charging time, and C0 to C n-1 represents each parameter of the fitting function, and n is the number of temperature sampling points.

[0047] Specifically, if equation (1) is used as a representative equation for the fitting function, the number of parameters is n. When charging begins, the terminal temperature is collected by a temperature sensor placed at the terminal of the charging device, and recorded together with the time as the charging parameter (t0, T0). Temperature collection and recording is performed once per sampling period, and n sampling points (t0, T0), (t1, T1), ..., (tn-1, Tn-1) are finally obtained. Then, the charging parameters of these n sampling points are substituted into the one-dimensional Taylor equation (1) to obtain each parameter C0 to C n-1 Solve and solve C0~C n-1 By substituting into equation (1), the construction of the temperature prediction model for the charging device is completed, and the temperature at the next sampling time can be predicted using the completed equation (1). By this analogy, the prediction of the temperature change trend during charging of the charging device is completed.

[0048] It should be noted that the above formula (1) is only one type of fitting function, and other fitting functions may be substituted to achieve the same effect. In other embodiments of the present disclosure, the fitting function may be expressed as follows:

number

[0049] In addition to the above formulas (1) and (2), the fitting function may be expressed by other formulas according to the actual situation, that is, the above two types of fitting functions may be replaced by other types of functions to achieve better fitting accuracy and prediction effect.

[0050] In step S3, if it is determined based on the temperature change that the highest predicted temperature will exceed a predetermined temperature threshold, the charging current is limited before the highest predicted temperature exceeds the predetermined temperature threshold. The predetermined temperature threshold of the charging device may be predetermined according to the actual application requirements of the charging device. For example, the predetermined temperature threshold may be set to the highest heat resistance temperature of the material of the charging port.

[0051] Specifically, after the fitting function is constructed, the temperature of the charging device at all times during charging can be calculated using the fitting function, and the maximum temperature during charging can be taken as the highest predicted temperature. The highest predicted temperature can then be compared with a predetermined temperature threshold. For example, assuming that the temperature Tn of the charging socket at predicted time tn is the highest predicted temperature during the entire charging process, the temperature Tn can be compared with a predetermined temperature threshold. If Tn is greater than the predetermined temperature threshold, it can be determined that an over-temperature event will occur during charging. Therefore, the charging current can be adjusted before time tn is reached, i.e., the charging current can be reduced in advance before the temperature exceeds the predetermined temperature limit to reduce the temperature of the charging device during charging and thereby prevent the over-temperature event from occurring. For example, the charging current can be adjusted at the current time when the over-temperature event is predicted to occur, or at a predetermined time tn hours before the adjustment time. The time interval between the adjustment time and tn can be set according to actual conditions. If it is determined that the temperature Tn does not exceed the predetermined temperature threshold, the charging device will not encounter an over-temperature phenomenon during the entire charging process, and there is no need to limit the charging current, i.e., the charging power, and the entire charging operation will be completed at that charging current. Therefore, this method uses a mathematical model to predict the temperature and determine in advance whether the charging device will be over-temperature during charging, which is safer and more reliable than traditional temperature protection methods.

[0052] In one embodiment of the present disclosure, limiting the charging current before the highest predicted temperature exceeds a predetermined temperature threshold includes limiting the charging current in a stepwise manner so that the highest predicted temperature falls within a predetermined temperature range, which can be set according to actual conditions.

[0053] That is, if the charging device determines that an over-temperature phenomenon exists during charging, it first adjusts the charging current by a small amount, then obtains the updated temperature change trend of the charging device, re-obtains the highest predicted temperature during charging based on the updated temperature change trend, and then determines whether the re-obtained highest predicted temperature is within a predetermined temperature range. If it still does not meet the requirements of the predetermined temperature range, it adjusts the charging current again. After repeating this cycle, if it determines that the updated highest predicted temperature does not exceed the predetermined temperature range, it does not adjust the charging current and uses the current current as the charging current to complete the entire charging process. This allows the charging current to be adjusted more quickly and effectively, and ensures as large a charging current as possible when the charging device does not experience over-temperature.

[0054] In one embodiment of the present disclosure, the step of limiting the charging current by gradually adjusting the charging current includes the steps of determining an initial current during charging, reducing the initial current by a predetermined step size to obtain a first current, and, when controlling the charging device to charge the device at the first current, obtaining charging parameters for a first predetermined time period, predicting a temperature change trend of the charging device based on the charging parameters for the first predetermined time period, obtaining an updated maximum predicted temperature, and, if the updated maximum predicted temperature exceeds an upper limit value of a predetermined temperature range, continuing to reduce the first current by the predetermined step size until the updated maximum predicted temperature becomes smaller than the upper limit value of the predetermined temperature range. The first predetermined time period and the predetermined step size can be set according to actual conditions.

[0055] Specifically, assuming that the predetermined temperature interval is [T', T''], the predetermined step size is ΔI, and the initial current during charging is I, if it is predicted that a maximum predicted temperature greater than the predetermined temperature threshold will exist during charging, ΔI is subtracted from the initial current I to obtain a first current I1, charging is continued at the first current I1, temperature sampling is performed again using the temperature sensor to obtain n charging parameters within the first predetermined time, the reacquired n charging parameters are substituted into the above equation (1) or (2) to obtain a new temperature prediction model for the charging device, and then the charging parameters and temperature prediction model are reacquired to re-predict the temperature change trend of the charging device and obtain an updated maximum predicted temperature T1, temperature T1 is compared with the upper limit value T'' of the predetermined temperature interval, and if T1 is greater than T'', I1 is continued to be lowered by ΔI, and the above operation is repeated until the updated maximum predicted temperature T1 becomes equal to or less than the upper limit value T''.

[0056] If the updated predicted maximum temperature does not exceed the upper limit of the predetermined temperature interval, the predicted maximum temperature is compared with the lower limit of the predetermined temperature interval. In one embodiment of the present disclosure, the step of limiting the charging current in a manner of gradually adjusting the charging current further includes, when controlling the charging device to charge the device at a first current, determining a relationship between the updated predicted maximum temperature and the lower limit of the predetermined temperature interval, and if the updated predicted maximum temperature is lower than the lower limit of the predetermined temperature interval, determining a second current based on the initial current and the first current, and when controlling the charging device to charge the device at the second current, obtaining charging parameters for a second predetermined time period, predicting a temperature change trend of the charging device based on the charging parameters for the second predetermined time period, obtaining an updated predicted maximum temperature, and if the updated predicted maximum temperature is still lower than the lower limit of the predetermined temperature interval, applying the second current value to the first current until the updated predicted maximum temperature is equal to or greater than the lower limit of the predetermined temperature interval, and the second current is higher than the first current and lower than the initial current, the second predetermined time period being set according to actual application circumstances.

[0057] In one embodiment of the present disclosure, determining the second current based on the initial current and the first current includes adding the initial current and the first current and then dividing the result in half to obtain the second current.

[0058] Specifically, let us continue to describe the predetermined temperature range as [T', T''], the initial current during charging as I, and the first current as I1. Then, the temperature T1 below T'' is compared with the lower limit value T' of the predetermined temperature range. If T1 is smaller than T', the second current I2 is calculated using the formula (I+I1) / 2=I2. The current I2 is used as the charging current to perform charging. Charging parameters are obtained within a second predetermined time, a new temperature prediction model is obtained using the above method, and the newly obtained charging parameters and temperature prediction model are used as the charging current. A new maximum predicted temperature is obtained based on the model and recorded as temperature T2, and temperature T2 is compared with the lower limit value T'. If temperature T2 is still smaller than T', then I1 = I2, i.e., I2 is added to I1, and the re-added I1 is substituted into the formula (I + I1) / 2 = I2, and a new second current I2 is re-obtained as the charging current to perform charging. The above operation is repeated to re-obtain the prediction model and the corresponding updated maximum predicted temperature T2, and this analogy continues until the maximum predicted temperature T2 of the charging device is equal to or greater than the lower limit value T'.

[0059] Furthermore, in one embodiment of the present disclosure, the step of limiting the charging current in a manner of gradually adjusting the charging current further includes, when controlling the charging device to charge the device with the second current, if the updated highest predicted temperature is greater than the upper limit value of the specified temperature range, assigning the value of the second current to the initial current until the updated highest predicted temperature becomes equal to or less than the upper limit value of the specified temperature range.

[0060] That is, if the highest predicted temperature T2 predicted during charging with the second current I2 is greater than the upper limit T'', I2 is added to the initial current I, i.e., I = I2, and the newly added I is substituted into the formula (I + I1) / 2 = I2 to obtain a new second current I2. The above operation is repeated until T2 becomes equal to or less than the upper limit T'', and a new highest predicted temperature T2 is obtained.

[0061] In this embodiment, after predicting the temperature rise of the charging device using the above fitting function, the charging current is first adjusted small steps using a predetermined step size, and the temperature change trend of the charging device at this time is detected to obtain a new predetermined maximum temperature. Next, based on the relationship between the re-obtained predetermined maximum temperature and a predetermined temperature range, if the re-obtained predetermined maximum temperature is greater than the predetermined temperature range, the current is adjusted further using a predetermined step size. If the re-obtained predetermined maximum temperature is smaller than the predetermined temperature range, the charging current is adjusted to the intermediate value before and after the change to re-obtain the predetermined maximum temperature. In this way, the current average value is continuously calculated and adjusted until the updated predetermined maximum temperature fluctuates within the allowable range (i.e., the predetermined temperature range), and the charging current adjustment is stopped, and it is considered that the charging current has reached an optimal value. This method allows the charging process to automatically reach the maximum allowable charging current if the charging device does not experience overtemperature, thereby avoiding the problem of difficult to set traditional temperature thresholds.

[0062] In addition to the above formula (I+I1) / 2=I2, the second current can also be obtained by manually setting it according to the actual situation.

[0063] In one embodiment of the present disclosure, the step of limiting the charging current by gradually adjusting the charging current further includes, when controlling the charging device to charge the device with the second current, maintaining the current charging current if the updated highest predicted temperature is within a predetermined temperature range.

[0064] That is, when the charging current is the second current I2, if the current temperature T2 satisfies T'≦T1≦T'', the adjustment of the charging current is stopped and the charging operation continues with the second current I2 as the charging current until charging is completed.

[0065] In one embodiment of the present disclosure, the step of limiting the charging current by gradually adjusting the charging current further includes, when controlling the charging device to charge the device with a first current, maintaining the current charging current if the updated highest predicted temperature is within a predetermined temperature range.

[0066] That is, if the highest predicted temperature T1 predicted during charging at the first current I1 satisfies T'≦T1≦T'', the current adjustment is stopped and charging continues at the first current I1 until charging is completed.

[0067] As can be understood, during charging, the adjustment of the charging current is further controlled by the battery, motor, electrical control components, etc. in the equipment, so the above-mentioned over-temperature protection method for the charging device needs to control the charging current under comprehensive conditions in combination with the limitations of other components of the equipment, and meet the temperature limit requirements of each component.

[0068] In one specific embodiment of the present disclosure, a temperature sensor is attached to the terminal of a charging device, and the real-time temperature of the terminal is collected as the temperature of the charging device. As shown in Figures 3 and 4, the overtemperature protection method for the charging device includes the following steps S101 to S107, where the predetermined number of samples is N, the fitting function equation is a one-dimensional Taylor equation with N unknown parameters, that is, the number of parameters in the equation is N, and the predetermined temperature threshold of the charging device is the highest heat resistance temperature of the charging port material.

[0069] In S101, charging begins, the time is recorded as 0 s, and the sensor records the initial ambient temperature and begins to collect the terminal temperature.

[0070] In S102, the terminal temperature T and the charging time t are collected once at each predetermined sampling time and recorded as charging parameters (t, T).

[0071] In S103, it is determined whether the number of sampling points is equal to or greater than N. If Yes, step S104 is executed, and if No, step S102 is executed.

[0072] In S104, the N charging parameters are substituted into a Taylor equation of N unknown parameters in one dimension, each parameter is obtained, and a temperature prediction model for the charging device is obtained.

[0073] In S105, it is determined whether the maximum predicted temperature determined by the charging parameters and the temperature change tendency predicted by the temperature prediction model is greater than a predetermined temperature threshold. If the result is Yes, step S106 is executed, and if the result is No, step S107 is executed.

[0074] In S106, before the temperature of the terminal reaches a predetermined temperature threshold, the charging current is limited by adjusting the charging current in a stepwise manner.

[0075] In S107, charging continues at the current current until charging is completed.

[0076] As shown in FIG. 4, the specific operation steps of the above step S106 include the following steps S201 to S210, where the predetermined temperature interval is [T', T''] and the predetermined step size is ΔI.

[0077] In S201, the initial current I during charging is determined.

[0078] In S202, the initial current I is reduced by ΔI, and the first current value I1 and the updated highest predicted temperature T1 are obtained.

[0079] In S203, it is determined whether T1 is greater than T''. If Yes, step S202 is executed, and if No, step S204 is executed.

[0080] In S204, it is determined whether T1 is smaller than T'. If Yes, step S206 is executed, and if No, step S205 is executed.

[0081] In S205, the current charging current is maintained until charging is completed.

[0082] In S206, the charging current is adjusted to a second current I2=(I+I1) / 2, and an updated maximum predicted temperature T2 is obtained.

[0083] In S207, it is determined whether T2 is smaller than T'. If Yes, step S208 is executed, and if No, step S209 is executed.

[0084] In S208, the value of I2 is assigned to I1, and step S206 is executed.

[0085] In S209, it is determined whether T2 is greater than T''. If Yes, step S210 is executed, and if No, step S205 is executed.

[0086] In S210, the value of I2 is assigned to I, and step S206 is executed.

[0087] As described above, the over-temperature protection method for a charging device according to an embodiment of the present disclosure first obtains charging parameters of the charging device during charging, the charging parameters including time and temperature, where time and temperature have a corresponding relationship, then predicts the temperature change trend of the charging device based on the charging parameters, and finally, if it is determined based on the temperature change trend that the highest predicted temperature will exceed a predetermined temperature threshold, limits the charging current before the highest predicted temperature exceeds the predetermined temperature threshold. In this way, the method predicts the temperature change trend of the charging device based on the charging parameters, can determine in advance whether the charging device will be over-temperature during charging, and can adjust the charging current more quickly and effectively, which is safer and more reliable.

[0088] Corresponding to the above embodiment, the present disclosure further provides an over-temperature protection device for a charging device.

[0089] As shown in FIG. 5 , the over-temperature protection device for a charging device in an embodiment of the present disclosure may include an acquisition module 10, a prediction module 20, and a protection control module 30.

[0090] The acquisition module 10 acquires charging parameters of the charging device during charging, the charging parameters including time and temperature, which have a corresponding relationship. The prediction module 20 predicts a temperature change trend of the charging device based on the charging parameters. If the protection control module 30 determines based on the temperature change trend that the highest predicted temperature will exceed a predetermined temperature threshold, it limits the charging current before the highest predicted temperature exceeds the predetermined temperature threshold.

[0091] In one embodiment of the present disclosure, the prediction module 20 predicts the temperature change trend of the charging device based on the charging parameters. Specifically, the prediction module 20 determines charging parameters and a fitting function for multiple sampling points, substitutes the charging parameters of each sampling point into the fitting function to obtain each parameter in the fitting function, substitutes each obtained parameter into the fitting function to obtain a temperature prediction model of the charging device, and predicts the temperature change trend of the charging device based on the charging parameters and the temperature prediction model.

[0092] In one embodiment of the present disclosure, the fitting function in the prediction module 20 is expressed as follows: T=C0+C1t+C2t 2 +C3t 3 +…+C n-1 t n-1 Here, T represents the temperature of the charging device, t represents the charging time, and C0 to C n-1 represents each parameter of the fitting function, and n is the number of temperature sampling points.

[0093] In another embodiment of the present disclosure, the fitting function in the prediction module 20 is expressed as:

number

[0094] In one embodiment of the present disclosure, the protection and control module 30 limits the charging current before the highest predicted temperature exceeds a predetermined temperature threshold, specifically, limits the charging current in a stepwise manner to keep the highest predicted temperature within a predetermined temperature range.

[0095] In one embodiment of the present disclosure, the protection and control module 30 limits the charging current by adjusting the charging current in stages. Specifically, the protection and control module 30 determines an initial current during charging, reduces the initial current by a predetermined step size, obtains a first current, and controls the charging device to charge the device at the first current. When the protection and control module 30 obtains charging parameters within a first predetermined time period, predicts the temperature change trend of the charging device based on the charging parameters within the first predetermined time period, obtains an updated maximum predicted temperature, and if the updated maximum predicted temperature exceeds the upper limit value of the predetermined temperature range, continues to reduce the first current by the predetermined step size until the updated maximum predicted temperature no longer exceeds the upper limit value of the predetermined temperature range.

[0096] In one embodiment of the present disclosure, the protection and control module 30 limits the charging current by gradually adjusting the charging current. Specifically, when controlling the charging device to charge the device with a first current, if the updated predicted maximum temperature does not exceed the upper limit of the predetermined temperature range, the protection and control module 30 further determines the relationship between the updated predicted maximum temperature and the lower limit of the predetermined temperature range. If the updated predicted maximum temperature is lower than the lower limit of the predetermined temperature range, the protection and control module 30 determines a second current based on the initial current and the first current. When controlling the charging device to charge the device with the second current, the protection and control module 30 obtains charging parameters for a second predetermined time period and predicts the temperature change trend of the charging device based on the charging parameters for the second predetermined time period to obtain an updated predicted maximum temperature. If the updated predicted maximum temperature is still lower than the lower limit of the predetermined temperature range, the protection and control module 30 applies the value of the second current to the first current until the updated predicted maximum temperature is equal to or greater than the lower limit of the predetermined temperature range, and the second current is greater than the first current and less than the initial current.

[0097] In one embodiment of the present disclosure, the protection and control module 30 limits the charging current by gradually adjusting the charging current. Specifically, when controlling the charging device to charge the device with the second current, if the updated highest predicted temperature is greater than the upper limit of the specified temperature range, the protection and control module 30 assigns the value of the second current to the initial current until the updated highest predicted temperature becomes equal to or less than the upper limit of the specified temperature range.

[0098] In one embodiment of the present disclosure, the protection control module 30 determines the second current based on the initial current and the first current, specifically, by adding the initial current and the first current and then dividing the result in half to obtain the second current.

[0099] In one embodiment of the present disclosure, the protection control module 30 limits the charging current by gradually adjusting the charging current. Specifically, when controlling the charging device to charge the device with a second current, if the updated highest predicted temperature is within a predetermined temperature range, the protection control module 30 maintains the current charging current.

[0100] In one embodiment of the present disclosure, the protection control module 30 limits the charging current by gradually adjusting the charging current. Specifically, when controlling the charging device to charge the device with a first current, if the updated highest predicted temperature is within a predetermined temperature range, the protection control module 30 maintains the current charging current.

[0101] For details not disclosed in the over-temperature protection device for a charging device of the embodiment of the present disclosure, please refer to the details disclosed in the over-temperature protection method for a charging device of the above embodiment of the present disclosure, and detailed explanations will be omitted here.

[0102] As described above, the over-temperature protection device for a charging device according to an embodiment of the present disclosure uses an acquisition module to acquire charging parameters of the charging device during charging, a prediction module to predict the temperature change trend of the charging device based on the charging parameters, and a protection control module to determine that the highest predicted temperature will exceed a predetermined temperature threshold based on the temperature change trend, and then limits the charging current before the highest predicted temperature exceeds the predetermined temperature threshold. By predicting the temperature change trend of the charging device based on the charging parameters, the device can predict in advance whether the charging device will be overheated during charging, and adjust the charging current more quickly and effectively, resulting in greater safety and reliability.

[0103] Corresponding to the above embodiment, the present disclosure further provides an electric vehicle.

[0104] As shown in FIG. 6 , an electric vehicle 200 according to an embodiment of the present disclosure may include a memory 210, a processor 220, and a charging device over-temperature protection program stored in the memory 210 and executable by the processor 220, and when the processor 220 executes the over-temperature protection program, the charging device over-temperature protection method is realized.

[0105] The electric vehicle according to the embodiment of the present disclosure is based on the charging device over-temperature protection method and predicts the temperature change trend of the charging device using charging parameters, thereby determining in advance whether the charging device is over-temperature during charging, and adjusting the charging current more quickly and effectively, making it safer and more reliable.

[0106] Corresponding to the above embodiment, the present disclosure further provides a computer-readable storage medium.

[0107] A computer-readable storage medium according to an embodiment of the present disclosure stores an over-temperature protection program for a charging device, and when the over-temperature protection program is executed by a processor, the above-described over-temperature protection method for a charging device is realized.

[0108] The computer-readable storage medium according to an embodiment of the present disclosure is based on the above-mentioned charging device over-temperature protection method, and can predict the temperature change trend of the charging device according to charging parameters, thereby determining in advance whether the charging device is over-temperature during charging, and can adjust the charging current more quickly and effectively, which is safer and more reliable.

[0109] It should be noted that the logic and / or steps depicted in flowcharts or otherwise described in this disclosure may be viewed, for example, as an ordered list of executable instructions for implementing logical functions, and may be tangibly embodied in any computer-readable medium for use by or in combination with an instruction execution system, device, or apparatus (e.g., a computer-based system, a processor-including system, or other system capable of reading instructions from and executing instructions from an instruction execution system, device, or apparatus). As used herein, a "computer-readable medium" may refer to any device that can store, store, communicate, propagate, or transmit a program for use by or in combination with an instruction execution system, device, or apparatus. More specific examples (non-exhaustive list) of computer-readable storage media include an electrical connection having one or more wires (electronic device), a portable computer disk box (magnetic device), random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), fiber optic device, and portable read-only memory (CD-ROM). The computer readable medium may also be paper or other suitable medium on which the program may be printed, such that the program may be obtained electronically and thereafter stored in computer memory, for example, by optically scanning the paper or other medium and then editing, interpreting, or processing in any other suitable manner as needed.

[0110] It should be understood that each part of the present disclosure can be realized by hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be realized by software or firmware stored in a memory and executed by an appropriate instruction execution system. For example, when realized by hardware, as in other embodiments, it can be realized by any one or combination of techniques known in the art, such as a discrete logic circuit having logic gate circuits for implementing logic functions on data signals, an application specific integrated circuit having appropriate combinational logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0111] In the description herein, references to the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. In the description herein, the exemplary expressions of the above terms are not necessarily limited to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined as appropriate in any one or more embodiments or examples.

[0112] Additionally, the terms "first" and "second" are for descriptive purposes only and should not be understood to denote or suggest relative importance or to implicitly specify the number of technical features indicated. Thus, a feature qualified with "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of this disclosure, "plurality" means at least two, e.g., two, three, etc., unless explicitly and specifically limited.

[0113] Although the embodiments of the present disclosure have been shown and described above, the above embodiments are illustrative and should not be understood as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present disclosure.

Claims

1. acquiring charging parameters of the charging device during charging, the charging parameters including time and temperature, and the time and the temperature have a corresponding relationship; predicting a temperature change tendency of the charging device based on the charging parameters; and when it is determined based on the temperature change trend that the highest predicted temperature will exceed a predetermined temperature threshold, limiting the charging current before the highest predicted temperature exceeds the predetermined temperature threshold; The step of predicting a temperature change tendency of the charging device based on the charging parameters includes: determining charging parameters and fitting functions for a plurality of sampling points; Substituting the charging parameters of each of the sampling points into the fitting function to obtain each parameter in the fitting function; Substituting the acquired parameters into the fitting function to acquire a temperature prediction model for the charging device; and predicting a temperature change trend of the charging device based on the charging parameters and the temperature prediction model.

2. The fitting function is expressed by the following formula: T=C ０ +C １ t+C ２ t ２ +C ３ t ３ +…+C ｎ－１ t ｎ－１ 、 where T represents the temperature of the charging device, t represents the charging time, and C ０ ~C ｎ－１ 2. The method for protecting a charging device from overheating as claimed in claim 1, wherein x represents each parameter of the fitting function, and n is the number of temperature sampling points.

3. The fitting function is expressed by the following formula: [Equation 1] where T represents the temperature of the charging device, t represents the charging time, and A ０ , B １ ~B ｎ , C １ ~C ｎ 2. The method for protecting a charging device from overheating as claimed in claim 1, wherein x represents each parameter of the fitting function, and n is the number of temperature sampling points.

4. The step of limiting the charging current before the maximum predicted temperature exceeds the predetermined temperature threshold comprises:

2. The method of claim 1, further comprising limiting the charging current in a stepwise manner to keep the maximum predicted temperature within a predetermined temperature range.

5. The step of limiting the charging current in a stepwise manner includes: determining an initial current during charging; decreasing the initial current by a predetermined step size to obtain a first current; 5. The overtemperature protection method for a charging device of claim 4, further comprising the steps of: acquiring charging parameters within a first predetermined time; predicting a temperature change trend of the charging device based on the charging parameters within the first predetermined time; acquiring an updated maximum predicted temperature; and, if the updated maximum predicted temperature exceeds an upper limit value of the predetermined temperature interval, continuing to reduce the first current by a predetermined step size until the updated maximum predicted temperature no longer exceeds the upper limit value of the predetermined temperature interval.

6. The step of limiting the charging current in a stepwise manner includes: When the charging device is controlled to charge the device with the first current, if the updated highest predicted temperature does not exceed an upper limit value of the predetermined temperature range, further determining a relationship between the updated highest predicted temperature and a lower limit value of the predetermined temperature range, 6. The overtemperature protection method for a charging device of claim 5, further comprising the steps of: determining a second current based on the initial current and the first current, controlling the charging device to charge the equipment at the second current, obtaining charging parameters within a second predetermined time period, predicting a temperature change trend of the charging device based on the charging parameters within the second predetermined time period, obtaining the updated maximum predicted temperature, and, if the updated maximum predicted temperature is still lower than the lower limit value of the predetermined temperature period, providing the value of the second current as the first current until the updated maximum predicted temperature becomes equal to or greater than the lower limit value of the predetermined temperature period, and the second current being greater than the first current and less than the initial current.

7. A step of acquiring charging parameters of a charging device during charging, the charging parameters including time and temperature, and the time and the temperature being in a corresponding relationship; predicting a temperature change tendency of the charging device based on the charging parameters; and when it is determined based on the temperature change trend that the highest predicted temperature will exceed a predetermined temperature threshold, limiting the charging current before the highest predicted temperature exceeds the predetermined temperature threshold; The step of limiting the charging current before the maximum predicted temperature exceeds the predetermined temperature threshold comprises: limiting the charging current in a stepwise manner to make the highest predicted temperature fall within a predetermined temperature range; The step of limiting the charging current in a stepwise manner includes: determining an initial current during charging; decreasing the initial current by a predetermined step size to obtain a first current; When controlling the charging device to charge the equipment at the first current, the method includes steps of acquiring charging parameters within a first predetermined time period, predicting a temperature change trend of the charging device based on the charging parameters within the first predetermined time period, acquiring an updated maximum predicted temperature, and, if the updated maximum predicted temperature exceeds an upper limit value of the predetermined temperature interval, continuing to reduce the first current by a predetermined step size until the updated maximum predicted temperature does not exceed the upper limit value of the predetermined temperature interval. The step of limiting the charging current in a stepwise manner includes: When the charging device is controlled to charge the device with the first current, if the updated highest predicted temperature does not exceed an upper limit value of the predetermined temperature range, further determining a relationship between the updated highest predicted temperature and a lower limit value of the predetermined temperature range, If the updated highest predicted temperature is lower than the lower limit value of the predetermined temperature interval, determining a second current based on the initial current and the first current, controlling the charging device to charge the device at the second current, obtaining charging parameters within a second predetermined time period, predicting a temperature change trend of the charging device based on the charging parameters within the second predetermined time period, obtaining the updated highest predicted temperature, if the updated highest predicted temperature is still lower than the lower limit value of the predetermined temperature interval, providing the value of the second current as the first current until the updated highest predicted temperature becomes equal to or greater than the lower limit value of the predetermined temperature interval, and the second current being greater than the first current and less than the initial current; The step of limiting the charging current in a stepwise manner includes: and if the updated highest predicted temperature is greater than an upper limit value of the predetermined temperature range, applying the value of the second current as the initial current until the updated highest predicted temperature becomes equal to or less than the upper limit value of the predetermined temperature range.

8. determining a second current based on the initial current and the first current, 7. The method for protecting a charging device from over-temperature as claimed in claim 6, further comprising the step of adding the initial current and the first current and then dividing the sum by two to obtain the second current.

9. The step of limiting the charging current in a stepwise manner includes:

7. The method of claim 6, further comprising the step of: when controlling the charging device to charge the device with the second current, if the updated highest predicted temperature is within the predetermined temperature range, maintaining the current charging current as it is.

10. The step of limiting the charging current in a stepwise manner includes:

6. The method of claim 5, further comprising the step of: when controlling the charging device to charge the device with the first current, if the updated highest predicted temperature is within the predetermined temperature range, maintaining the current charging current as it is.

11. An electric vehicle comprising: a memory; a processor; and a charging device overtemperature protection program stored in the memory and executable by the processor, wherein when the processor executes the overtemperature protection program, the charging device overtemperature protection method according to any one of claims 1 to 10 is realized.

12. A computer-readable storage medium having a charging device overtemperature protection program stored therein, the computer-readable storage medium realizing the charging device overtemperature protection method according to any one of claims 1 to 10, when the overtemperature protection program is executed by a processor.

13. An overtemperature protection program for a charging device, characterized in that when the overtemperature protection program is executed by a processor, it realizes the overtemperature protection method for a charging device described in any one of claims 1 to 10.

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