Brake disc temperature determination method and system and computer readable storage medium

Abstract

The embodiment of the invention provides a brake disc temperature determining method and system and a computer readable storage medium, and the brake disc temperature determining method comprises the steps that from the first moment, the heat absorption power of a brake disc is determined according to the running state parameters of a vehicle; determining a natural heat dissipation coefficient according to the temperature of the brake disc; the natural heat dissipation power of the brake disc is determined according to the brake disc temperature, the environment temperature and the natural heat dissipation coefficient; according to the vehicle speed, the environment temperature and the convection heat dissipation coefficient, the convection heat dissipation power of the brake disc is determined; the temperature change of the brake disc in unit time is determined; and the temperature of the brake disc at the second moment is determined according to the temperature of the brake disc at the first moment, the time interval between the second moment and the first moment and the temperature change of the brake disc in the unit time. The natural heat dissipation coefficient is determined according to the temperature of the brake disc, and the natural heat dissipation coefficient can accurately reflect the natural heat dissipation capability of the brake disc at the current temperature, so that the temperature calculation of the brake disc at the second moment is more accurate.

Description

Technical Field

[0001] The present application relates to the technical field of brake disc temperature control, and in particular to a brake disc temperature determination method, system and computer-readable storage medium. Background Art

[0002] Brake disc temperature prediction is crucial to vehicle driving safety. If the temperature of the brake disc is too high, it may cause brake degradation and affect driving safety. Brake disc temperature prediction can also optimize the performance of the brake system and extend its service life. The driver can also make safer driving decisions based on temperature information to ensure that the vehicle maintains good braking performance under extreme conditions.

[0003] In the related art, when predicting the brake disc temperature, empirical parameters are mostly used for the thermal radiation coefficient that reflects the heat dissipation performance of the brake disc. This cannot well reflect the thermal radiation capacity of brake discs of different materials at different temperatures, which in turn causes inaccurate calculation of the heat dissipation of the brake disc, affecting the accuracy of the brake disc temperature prediction. Summary of the invention

[0004] The present application provides a brake disc temperature determination method, system and computer-readable storage medium to solve at least some of the problems in the related art.

[0005] On one hand, the present application provides a method for determining brake disc temperature, comprising:

[0006] Starting from the first moment, determining the heat absorption power of the brake disc according to the operating state parameters of the vehicle;

[0007] Determining the natural heat dissipation coefficient according to the brake disc temperature after the first moment and before the second moment;

[0008] Determining the natural heat dissipation power of the brake disc according to the brake disc temperature, the ambient temperature and the natural heat dissipation coefficient;

[0009] determining the convective heat dissipation power of the brake disc according to the vehicle speed, the ambient temperature and the convective heat dissipation coefficient after the first moment and before the second moment;

[0010] Determining the temperature change of the brake disc within a unit time according to the heat absorption power, the natural heat dissipation power and the convection heat dissipation power; and

[0011] The temperature of the brake disc at the second moment is determined according to the temperature of the brake disc at the first moment, the time interval between the second moment and the first moment, and the temperature change of the brake disc per unit time.

[0012] Optionally, determining the heat absorption power of the brake disc according to the operating state parameters of the vehicle includes: determining the heat absorption power of the brake disc according to the vehicle speed, deceleration, and front and rear wheel braking force distribution coefficient.

[0013] Optionally, determining the natural heat dissipation coefficient according to the brake disc temperature after the first moment and before a second moment includes:

[0014] In a first mapping relationship between a calibrated natural heat dissipation coefficient and a calibrated brake disc temperature, the calibrated natural heat dissipation coefficient corresponding to the calibrated brake disc temperature that is the same as the brake disc temperature is determined as the natural heat dissipation coefficient.

[0015] Optionally, the calibration method of the first mapping relationship includes:

[0016] Obtaining a first temperature drop curve of the temperature of the brake disc decreasing from a calibrated high temperature limit to a calibrated low temperature limit relative to time during the natural heat dissipation of the brake disc, wherein the natural heat dissipation includes radiation heat dissipation and conduction heat dissipation, and on the first temperature drop curve, the temperature range between the calibrated high temperature limit and the calibrated low temperature limit includes a plurality of continuous temperature intervals, each of the temperature intervals including a high temperature and a low temperature;

[0017] Determine the calibrated natural heat dissipation coefficient corresponding to the high temperature of each temperature interval according to the high temperature, the low temperature and their corresponding durations in each temperature interval, combined with the specific heat capacity corresponding to the high temperature of each temperature interval; and

[0018] The plurality of high temperatures and the plurality of natural heat dissipation coefficients corresponding thereto are fitted to obtain a first mapping relationship between the calibrated natural heat dissipation coefficient and the calibrated brake plate temperature.

[0019] Optionally, after fitting the plurality of calibrated brake plate temperatures and the plurality of natural heat dissipation coefficients corresponding thereto to obtain a first mapping relationship between the calibrated natural heat dissipation coefficient and the calibrated brake plate temperature, the calibration method of the first mapping relationship further includes:

[0020] Starting from the calibrated high temperature limit, the temperature at the next moment is calculated according to the temperature at the previous moment and the natural heat dissipation coefficient corresponding to the temperature in the first mapping relationship, so as to obtain the temperatures at multiple moments and obtain a first simulated cooling curve of the brake disc;

[0021] The first simulated cooling curve is compared with the first cooling curve, and the first mapping relationship is adjusted and updated.

[0022] Optionally, determining the convective heat dissipation power of the brake disc according to the vehicle speed, ambient temperature, and convective heat dissipation coefficient after the first moment and before the second moment includes:

[0023] The convection heat dissipation coefficient is determined according to the vehicle speed after the first moment and before the second moment.

[0024] Optionally, determining the convection heat dissipation coefficient according to the vehicle speed after the first moment and before the second moment includes:

[0025] In a second mapping relationship between a calibrated convection heat dissipation coefficient and a calibrated vehicle speed, the calibrated convection heat dissipation coefficient corresponding to the calibrated vehicle speed that is the same as the vehicle speed is determined as the convection heat dissipation coefficient.

[0026] Optionally, the calibration method of the second mapping relationship includes:

[0027] Obtaining a second cooling curve of the temperature of the brake disc decreasing from a calibrated high temperature limit to a calibrated low temperature limit relative to time during the process of the natural heat dissipation and convection heat dissipation of the brake disc when the vehicle is traveling at a constant speed at different calibrated vehicle speeds; wherein different calibrated vehicle speeds correspond to different second cooling curves;

[0028] Starting from the calibrated high temperature limit, according to the temperature at the previous moment and the corresponding natural heat dissipation coefficient, ambient temperature, specific heat capacity corresponding to the temperature at the previous moment, different calibrated vehicle speeds, and a preset convection heat dissipation coefficient corresponding to the calibrated vehicle speed, the temperature at the next moment is calculated to obtain the temperatures at multiple moments, and obtain multiple second simulated temperature drop curves of the brake disc;

[0029] Comparing the second simulated cooling curve with the second cooling curve at the same calibrated vehicle speed, updating the preset convection heat dissipation coefficient corresponding to the calibrated vehicle speed, and obtaining the calibrated convection heat dissipation coefficient corresponding to the calibrated vehicle speed;

[0030] A plurality of the calibrated vehicle speeds and a plurality of the corresponding calibrated convection heat dissipation coefficients are fitted to obtain a second mapping relationship between the calibrated convection heat dissipation coefficients and the calibrated vehicle speeds.

[0031] Optionally, after fitting the plurality of calibrated vehicle speeds and the plurality of calibrated convection heat dissipation coefficients corresponding thereto to obtain a second mapping relationship between the calibrated convection heat dissipation coefficients and the calibrated vehicle speeds, the calibration method for the second mapping relationship further includes:

[0032] Obtaining a third temperature drop curve of the temperature of the brake disc decreasing from a calibrated high temperature limit value to a calibrated low temperature limit value relative to time during the process of the vehicle changing speeds at different calibrated vehicle speeds;

[0033] Starting from the calibrated high temperature limit, the temperature at the next moment is calculated according to the temperature at the previous moment and the corresponding natural heat dissipation coefficient, the ambient temperature, the specific heat capacity corresponding to the temperature at the previous moment, the speed at the previous moment and the convection heat dissipation coefficient corresponding to the speed in the second mapping relationship, and the running state parameter of the vehicle, so as to obtain the temperatures at multiple moments and obtain a third simulated cooling curve of the brake disc;

[0034] The third simulated cooling curve is compared with the third cooling curve, and the second mapping relationship is adjusted and updated.

[0035] On the other hand, the present application provides a brake disc temperature determination system, including a memory, a processor, and a program stored in the memory and executable on the processor, wherein the brake disc temperature determination method is implemented when the processor executes the program.

[0036] On the other hand, the present application provides a computer-readable storage medium, on which a program is stored, and when the program is executed, a method for determining the temperature of a brake disc is implemented.

[0037] Compared with the related art, the method for determining the temperature of the brake disc provided by the present application determines the heat absorption power of the brake disc according to the running state parameters of the vehicle, determines the natural heat dissipation coefficient according to the temperature of the brake disc, determines the natural heat dissipation power according to the natural heat dissipation coefficient, determines the convection heat dissipation power according to the convection heat dissipation coefficient, and determines the temperature change of the brake disc in a unit time according to the heat absorption power, the natural heat dissipation power and the convection heat dissipation power. According to the temperature of the brake disc at the first moment, the time interval between the second moment and the first moment, and the temperature change of the brake disc in a unit time, the temperature of the brake disc at the second moment is determined.

[0038] By determining the natural heat dissipation coefficient based on the brake disc temperature, the ability of the brake disc to dissipate heat naturally at the current temperature can be accurately reflected, thereby facilitating accurate calculation of the temperature change caused by the natural heat dissipation of the brake disc according to thermodynamic formulas, making the temperature calculation of the brake disc at the second moment more accurate and improving the accuracy of the brake disc temperature prediction. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0040] Figure 1 The figure is a flow chart of a method for determining brake disc temperature according to an embodiment.

[0041] Figure 2 A schematic flow chart of a calibration method for a first mapping relationship shown in an embodiment.

[0042] Figure 3 is a schematic diagram of the first mapping relationship.

[0043] Figure 4 A schematic flow chart of a calibration method for a first mapping relationship shown in an embodiment.

[0044] Figure 5 The figure is a flow chart of a method for determining brake disc temperature according to another embodiment.

[0045] Figure 6 The figure is a flow chart of a calibration method of a second mapping relationship shown in an embodiment.

[0046] Figure 7 The figure is a flowchart of a calibration method of a second mapping relationship shown in another embodiment.

[0047] Figure 8 It is a structural block diagram of a brake disc temperature determination system shown in one embodiment. DETAILED DESCRIPTION

[0048] The present application provides a method, system and computer-readable storage medium for determining the temperature of a brake disc. The method, system and computer-readable storage medium for determining the temperature of a brake disc of the present application are described in detail below in conjunction with the accompanying drawings. The features of the following embodiments and implementations may be combined with each other if there is no conflict.

[0049] The present application provides a method for determining brake disc temperature, comprising:

[0050] Starting from the first moment, the heat absorption power of the brake disc is determined according to the operating state parameters of the vehicle.

[0051] The natural heat dissipation coefficient is determined according to the brake disc temperature after the first moment and before the second moment.

[0052] The natural heat dissipation power of the brake disc is determined based on the brake disc temperature, ambient temperature and natural heat dissipation coefficient.

[0053] The convective heat dissipation power of the brake disc is determined according to the vehicle speed, the ambient temperature and the convective heat dissipation coefficient after the first moment and before the second moment.

[0054] Determine the temperature change of the brake disc per unit time based on the heat absorption power, natural heat dissipation power and convection heat dissipation power.

[0055] The temperature of the brake disc at the second moment is determined according to the temperature of the brake disc at the first moment, the time interval between the second moment and the first moment, and the temperature change of the brake disc per unit time.

[0056] Compared with the related art, the vehicle control method provided by the present application determines the heat absorption power of the brake disc according to the running state parameters of the vehicle, determines the natural heat dissipation coefficient according to the temperature of the brake disc, determines the natural heat dissipation power according to the natural heat dissipation coefficient, determines the convection heat dissipation power according to the convection heat dissipation coefficient, and determines the temperature change of the brake disc in unit time according to the heat absorption power, natural heat dissipation power and convection heat dissipation power. According to the temperature of the brake disc at the first moment, the time interval between the second moment and the first moment, and the temperature change of the brake disc in unit time, the temperature of the brake disc at the second moment is determined.

[0057] By determining the natural heat dissipation coefficient based on the brake disc temperature, the ability of the brake disc to dissipate heat naturally at the current temperature can be accurately reflected, thereby facilitating accurate calculation of the temperature change caused by the natural heat dissipation of the brake disc according to thermodynamic formulas, making the temperature calculation of the brake disc at the second moment more accurate and improving the accuracy of the brake disc temperature prediction.

[0058] Please refer to Figure 1 , Figure 1 FIG. 1 is a flow chart of a method for determining brake disc temperature according to an embodiment. Figure 1 In the illustrated embodiment, the brake disc temperature determination method 10 includes steps 11 - 16 .

[0059] Step 11, starting from the first moment, determine the heat absorption power of the brake disc according to the operating state parameters of the vehicle. In some embodiments, determining the heat absorption power of the brake disc according to the operating state parameters of the vehicle includes: determining the heat absorption power of the brake disc according to the vehicle speed, deceleration, and the front and rear wheel braking force distribution coefficient. The heat absorbed by the brake disc is the heat generated by the friction of the brake disc during the braking process of the vehicle. Specifically, the heat absorption power p = 0.5×m×v×a×η, where m is the mass of the vehicle, v is the real-time speed of the vehicle, a is the real-time deceleration of the vehicle, and η is the dynamic front and rear braking force distribution coefficient.

[0060] Step 12, determining the natural heat dissipation coefficient according to the temperature of the brake disc after the first moment and before the second moment. The natural heat dissipation coefficient is related to the temperature of the brake disc and the material of the brake disc. The material of the brake disc installed on the vehicle is known and fixed. Therefore, it is necessary to determine the natural heat dissipation coefficient of the current brake disc at different temperatures. Among them, the natural heat dissipation coefficient represents the ability of the vehicle to dissipate heat through radiation and conduction when it is not in motion, and does not include the heat dissipation capacity through convection due to the relative movement between the vehicle and the air during the movement of the vehicle.

[0061] Step 13, determine the natural heat dissipation power of the brake disc according to the brake disc temperature, ambient temperature and natural heat dissipation coefficient. Specifically, the natural heat dissipation power is Among them, T drepresents the brake disc temperature, T0 represents the ambient temperature, ε(T d ) is the natural heat dissipation coefficient that changes with temperature.

[0062] Step 14, determining the convective heat dissipation power of the brake disc according to the vehicle speed, ambient temperature and convective heat dissipation coefficient after the first moment and before the second moment. The convective heat dissipation coefficient indicates the ability of the brake disc and the air to dissipate heat through convective heat dissipation when the vehicle is in motion. The convective heat dissipation coefficient is related to the relative motion between the air and the vehicle. When the vehicle is in motion, it is related to the speed of the vehicle, and different vehicle speeds have different convective heat dissipation coefficients. Specifically, the convective heat dissipation power p c =h(v)×(T d -T0), where T d represents the brake disc temperature, T0 represents the ambient temperature, v represents the vehicle speed, and h(v) represents the convection heat dissipation coefficient that changes with the vehicle speed.

[0063] Step 15, determining the temperature change of the brake disc per unit time according to the heat absorption power, natural heat dissipation power and convection heat dissipation power. Specifically, ΔT d =(pp r -p c ) / c(T d ) / m d , ΔT d is the temperature rise of the brake disc per unit time, m d is the thermal mass of the brake disc. Specifically, the thermal mass is the mass of the brake disc friction ring. c(T d ) is the specific heat capacity of the brake disc that changes with temperature, and the specific heat capacity of the brake disc corresponding to different temperatures is known.

[0064] Step 16, determining the temperature of the brake disc at the second moment according to the temperature of the brake disc at the first moment, the time interval between the second moment and the first moment, and the temperature change of the brake disc per unit time. Specifically, T d =T1+∫ΔT d dt, where T1 is the temperature of the brake disc at the first moment, T d In this way, the temperature of the brake disc at the second moment can be predicted, and the number of the second moments can be multiple, so that the temperature of the brake disc can be predicted.

[0065] Compared with the related art, the vehicle control method provided by the present application determines the heat absorption power of the brake disc according to the running state parameters of the vehicle, determines the natural heat dissipation coefficient according to the temperature of the brake disc, determines the natural heat dissipation power according to the natural heat dissipation coefficient, determines the convection heat dissipation power according to the convection heat dissipation coefficient, and determines the temperature change of the brake disc in unit time according to the heat absorption power, natural heat dissipation power and convection heat dissipation power. According to the temperature of the brake disc at the first moment, the time interval between the second moment and the first moment, and the temperature change of the brake disc in unit time, the temperature of the brake disc at the second moment is determined.

[0066] By determining the natural heat dissipation coefficient based on the brake disc temperature, the ability of the brake disc to dissipate heat naturally at the current temperature can be accurately reflected, thereby facilitating accurate calculation of the temperature change caused by the natural heat dissipation of the brake disc according to thermodynamic formulas, making the temperature calculation of the brake disc at the second moment more accurate and improving the accuracy of the brake disc temperature prediction.

[0067] In some embodiments, determining the natural heat dissipation coefficient according to the brake disc temperature after the first moment and before the second moment includes:

[0068] In the first mapping relationship between the calibrated natural heat dissipation coefficient and the calibrated brake disc temperature, the calibrated natural heat dissipation coefficient corresponding to the calibrated brake disc temperature which is the same as the brake disc temperature is determined as the natural heat dissipation coefficient. In this way, the natural heat dissipation coefficients of brake discs at different temperatures can be determined according to the first mapping relationship.

[0069] Please refer to Figure 2 , Figure 2 FIG. 1 is a flow chart of a calibration method for a first mapping relationship shown in an embodiment. Figure 2 In the illustrated embodiment, the calibration method 20 of the first mapping relationship includes steps 21 to 23 .

[0070] Step 21, obtaining a first cooling curve of the temperature of the brake disc from a calibrated high temperature limit to a calibrated low temperature limit relative to time during the natural heat dissipation of the brake disc. Brake discs of different materials have different calibrated high temperature limits, and different brake discs may also have different calibrated low temperature limits. In some embodiments, the calibrated high temperature limit of a cast iron brake disc can be set to 600 degrees, and the calibrated high temperature limit of a carbon ceramic brake disc can be set to 800 degrees. The calibrated low temperature limit can be set to 100 degrees. Among them, natural heat dissipation includes radiation heat dissipation and conduction heat dissipation. The vehicle can be parked in a windless environment to avoid convective heat exchange between the vehicle and the air to achieve natural heat dissipation of the brake disc.

[0071] On the first cooling curve, the temperature range between the calibrated high temperature limit and the calibrated low temperature limit includes a plurality of continuous temperature intervals, each temperature interval including a high temperature and a low temperature. The temperature intervals between the temperature intervals may be the same or different. In some embodiments, the temperature interval of each temperature interval is 2 degrees, that is, the temperature range between the calibrated high temperature limit and the calibrated low temperature limit is divided into a plurality of temperature intervals with a step length of 2 degrees.

[0072] Step 22, according to the high temperature, low temperature and corresponding duration of each temperature interval, combined with the specific heat capacity corresponding to the high temperature of each temperature interval, determine the calibrated natural heat dissipation coefficient corresponding to the high temperature of each temperature interval. Using numerical calculation thinking, in each temperature interval, according to Calculate the thermal radiation coefficient of the brake disc when the brake disc temperature is 600, 598, 596..., 104, 102, 100 one by one.

[0073] Step 23, fit the multiple high temperature and the corresponding multiple natural heat dissipation coefficients to obtain the first mapping relationship between the calibrated natural heat dissipation coefficient and the calibrated brake plate temperature. Specifically, you can use the polynomial fitting function of Excel to input the multiple high temperature and the corresponding multiple natural heat dissipation coefficients into Excel to obtain the fitting curve and the first mapping relationship expression. Please refer to Figure 3 , Figure 3 is a schematic diagram of the first mapping relationship. Figure 3 In the figure, the horizontal axis is temperature and the vertical axis is the natural heat dissipation coefficient. There are two curves in the figure, among which the points on the solid line are the natural heat dissipation coefficients corresponding to different temperatures, and the dotted line is the first mapping relationship curve after fitting, and the fit between the two is good.

[0074] Please refer to Figure 4 , Figure 4 FIG. 1 is a flow chart of a calibration method for a first mapping relationship shown in an embodiment. Figure 4 In the illustrated embodiment, after fitting multiple calibrated brake plate temperatures and their corresponding multiple natural heat dissipation coefficients to obtain a first mapping relationship between the calibrated natural heat dissipation coefficient and the calibrated brake plate temperature in step 23, the calibration method 20 of the first mapping relationship also includes steps 24 to 25.

[0075] Step 24, starting from the calibration of the high temperature limit, the temperature at the next moment is calculated according to the temperature at the previous moment and the natural heat dissipation coefficient corresponding to the temperature in the first mapping relationship, so as to obtain the temperatures at multiple moments and obtain the first simulated cooling curve of the brake disc. The first simulated cooling curve is a curve calculated by calculating the plotting points through the automated simulation software.

[0076] Step 25, compare the first simulated cooling curve with the first cooling curve, and adjust and update the first mapping relationship. Specifically, adjust and update the parameter values ​​in the first mapping relationship so that the first simulated cooling curve and the first cooling curve fit together and the two curves are closer, thereby obtaining the adjusted and updated first mapping relationship.

[0077] Please refer to Figure 5 , Figure 5 FIG. 2 is a flow chart of a method for determining the temperature of a brake disc shown in another embodiment. Figure 5 In the illustrated embodiment, before determining the convective heat dissipation power of the brake disc according to the vehicle speed, ambient temperature and convective heat dissipation coefficient after the first moment and before the second moment in step 14, the brake disc temperature determination method 10 includes step 17, and the brake disc temperature determination method 10 includes steps 11 to 17.

[0078] Step 11, starting from the first moment, determining the heat absorption power of the brake disc according to the operating state parameters of the vehicle.

[0079] Step 12, determining the natural heat dissipation coefficient according to the brake disc temperature after the first moment and before the second moment.

[0080] Step 13, determining the natural heat dissipation power of the brake disc according to the brake disc temperature, the ambient temperature and the natural heat dissipation coefficient.

[0081] Step 17, determining the convection heat dissipation coefficient according to the vehicle speed after the first moment and before the second moment.

[0082] Step 14, determining the convective heat dissipation power of the brake disc according to the vehicle speed, the ambient temperature and the convective heat dissipation coefficient after the first moment and before the second moment.

[0083] Step 15, determining the temperature change of the brake disc in unit time according to the heat absorption power, the natural heat dissipation power and the convection heat dissipation power.

[0084] Step 16, determining the temperature of the brake disc at the second moment according to the temperature of the brake disc at the first moment, the time interval between the second moment and the first moment, and the temperature change of the brake disc per unit time.

[0085] In the above steps, there is no time limit for step 11, step 13 and step 14, and they can be executed in sequence or simultaneously. This application does not limit this. Step 12 is executed before step 13, and step 17 is executed before step 14.

[0086] In some embodiments, determining the convection heat dissipation coefficient according to the vehicle speed after the first moment and before the second moment includes:

[0087] In the second mapping relationship between the calibrated convection heat dissipation coefficient and the calibrated vehicle speed, the calibrated convection heat dissipation coefficient corresponding to the calibrated vehicle speed equal to the vehicle speed is determined as the convection heat dissipation coefficient. In this way, the convection heat dissipation coefficient of the brake disc at different speeds can be determined according to the second mapping relationship.

[0088] Please refer to Figure 6 , Figure 6 FIG. 1 is a flow chart of a calibration method for a second mapping relationship shown in an embodiment. Figure 6 In the illustrated embodiment, the calibration method 30 of the second mapping relationship includes steps 31 to 34 .

[0089] Step 31, obtaining a second cooling curve of the temperature of the brake disc from a calibrated high temperature limit to a calibrated low temperature limit relative to time during the natural heat dissipation and convection heat dissipation of the brake disc when the vehicle is traveling at different calibrated vehicle speeds. Different calibrated vehicle speeds correspond to different second cooling curves. When the vehicle is traveling at a constant speed, the speed remains unchanged, and the corresponding convection heat dissipation coefficient remains unchanged and is a fixed value.

[0090] Step 32, starting from the calibration high temperature limit, according to the temperature at the previous moment and its corresponding natural heat dissipation coefficient, ambient temperature, specific heat capacity corresponding to the temperature at the previous moment, different calibrated vehicle speeds, and preset convection heat dissipation coefficients corresponding to the calibrated vehicle speeds, the temperature at the next moment is calculated to obtain the temperatures at multiple moments, and obtain multiple second simulated cooling curves of the brake disc. Among them, the preset convection heat dissipation coefficient corresponding to the calibrated vehicle speed is a preset test convection heat dissipation coefficient, the initial value can be set arbitrarily, or can be set according to experience, and needs to be iteratively updated later.

[0091] Step 33, compare the second simulated cooling curve and the second cooling curve with the same calibration speed, update the preset convection heat dissipation coefficient corresponding to the calibration speed, and obtain the calibration convection heat dissipation coefficient corresponding to the calibration speed. The purpose of updating the preset convection heat dissipation coefficient corresponding to the calibration speed is to make the second simulated cooling curve and the second cooling curve with the same calibration speed fit together, and the difference between the second simulated cooling curve and the second cooling curve with the same calibration speed is smaller. Update the preset convection heat dissipation coefficient corresponding to the calibration speed to obtain the calibration convection heat dissipation coefficient corresponding to the calibration speed.

[0092] Step 34 , fitting the plurality of calibrated vehicle speeds and the plurality of calibrated convection heat dissipation coefficients corresponding thereto to obtain a second mapping relationship between the calibrated convection heat dissipation coefficients and the calibrated vehicle speeds.

[0093] Please refer to Figure 7 , Figure 7 FIG. 1 is a flow chart of a calibration method for a second mapping relationship shown in another embodiment. Figure 7In the illustrated embodiment, after fitting multiple calibrated vehicle speeds and their corresponding multiple calibrated convection heat dissipation coefficients to obtain a second mapping relationship between the calibrated convection heat dissipation coefficients and the calibrated vehicle speeds in step 34, the calibration method 30 of the second mapping relationship further includes steps 35 to 37.

[0094] Step 35, obtaining a third temperature drop curve of the temperature of the brake disc from the calibrated high temperature limit to the calibrated low temperature limit relative to time during the vehicle's speed change at different calibrated vehicle speeds. This process is during the normal driving of the vehicle, which can be accelerated and decelerated, and can also be braked, simulating the normal driving condition of the vehicle.

[0095] Step 36, starting from calibrating the high temperature limit, calculate the temperature at the next moment according to the temperature at the previous moment and its corresponding natural heat dissipation coefficient, ambient temperature, specific heat capacity corresponding to the temperature at the previous moment, speed at the previous moment and the convection heat dissipation coefficient corresponding to the speed in the second mapping relationship, and vehicle operating state parameters, so as to obtain the temperatures at multiple moments and obtain a third simulated cooling curve of the brake disc.

[0096] Specifically, the heat absorption power of the brake disc is calculated by the running state parameters of the vehicle, the natural heat dissipation power of the brake disc is calculated by the temperature at the last moment and its corresponding natural heat dissipation coefficient, ambient temperature, and specific heat capacity corresponding to the temperature at the last moment, and the convection heat dissipation power of the brake disc is calculated by the speed at the last moment and the convection heat dissipation coefficient corresponding to the speed in the second mapping relationship and ambient temperature. The temperatures at different moments are obtained according to the heat absorption power, natural heat dissipation power, and convection heat dissipation power, and then the third simulated cooling curve of the brake disc is obtained.

[0097] Step 37, compare the third simulated cooling curve with the third cooling curve, and adjust and update the second mapping relationship. Specifically, adjust and update the value of the parameter in the second mapping relationship, and the goal of the adjustment is to make the third simulated cooling curve and the third cooling curve fit together. When the third simulated cooling curve and the third cooling curve fit best, the value of the parameter in the second mapping relationship is the parameter value of the adjusted and updated second mapping relationship, and the adjusted and updated second mapping relationship is obtained.

[0098] Another aspect of the present application provides a brake disc temperature determination system, Figure 8 FIG. 1 is a block diagram of a brake disc temperature determination system according to an embodiment. Figure 8 As shown, the determination system includes a memory, a processor 1, and a program stored in the memory and executable on the processor 1. When the processor 1 executes the program, the brake disc temperature determination method is implemented.

[0099] In some embodiments, the determination system may include a computer-readable storage medium 2, which may store a program that can be called by the processor 1 and may include a non-volatile storage medium. In some embodiments, the determination system may include a memory 3 and an interface 4. In some embodiments, the control device may also include other hardware according to actual applications.

[0100] On the other hand, the present application provides a computer-readable storage medium, on which a program is stored, and when the program is executed, a method for determining the temperature of a brake disc is implemented. In some embodiments, the form of a computer program product implemented on one or more computer-readable storage media 2 (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing program code can be adopted. The computer-readable storage medium 2 includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. The information can be a computer-readable instruction, a data structure, a module of a program, or other data. Examples of computer-readable storage media 2 include but are not limited to: phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, read-only compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassette, tape disk storage or other magnetic storage device or any other non-transmission medium that can be used to store information that can be accessed by a computing device.

[0101] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the application disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0102] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for determining brake disc temperature, characterized in that: include: Starting from the first moment, determining the heat absorption power of the brake disc according to the operating state parameters of the vehicle; Determining a natural heat dissipation coefficient according to a brake disc temperature between a second moment and a second moment after the first moment; Determining the natural heat dissipation power of the brake disc according to the brake disc temperature, the ambient temperature and the natural heat dissipation coefficient; determining the convective heat dissipation power of the brake disc according to the vehicle speed, the ambient temperature and the convective heat dissipation coefficient after the first moment and before the second moment; Determining a temperature change of the brake disc within a unit time according to the heat absorption power, the natural heat dissipation power and the convection heat dissipation power; and The temperature of the brake disc at the second moment is determined according to the temperature of the brake disc at the first moment, the time interval between the second moment and the first moment, and the temperature change of the brake disc per unit time.

2. The method for determining the brake disc temperature according to claim 1, characterized in that: Determining the heat absorption power of the brake disc according to the operating state parameters of the vehicle includes: determining the heat absorption power of the brake disc according to the vehicle speed, deceleration, and front and rear wheel braking force distribution coefficient.

3. The method for determining the brake disc temperature according to claim 1, characterized in that: Determining the natural heat dissipation coefficient according to the brake disc temperature after the first moment and before the second moment includes: In a first mapping relationship between a calibrated natural heat dissipation coefficient and a calibrated brake disc temperature, the calibrated natural heat dissipation coefficient corresponding to the calibrated brake disc temperature that is the same as the brake disc temperature is determined as the natural heat dissipation coefficient.

4. The method for determining the brake disc temperature according to claim 3, characterized in that: The calibration method of the first mapping relationship includes: Obtaining a first temperature drop curve of the temperature of the brake disc decreasing from a calibrated high temperature limit to a calibrated low temperature limit relative to time during the natural heat dissipation of the brake disc, wherein the natural heat dissipation includes radiation heat dissipation and conduction heat dissipation, and on the first temperature drop curve, the temperature range between the calibrated high temperature limit and the calibrated low temperature limit includes a plurality of continuous temperature intervals, each of the temperature intervals including a high temperature and a low temperature; Determine the calibrated natural heat dissipation coefficient corresponding to the high temperature of each temperature interval according to the high temperature, the low temperature and their corresponding durations in each temperature interval, combined with the specific heat capacity corresponding to the high temperature of each temperature interval; and The plurality of high temperatures and the plurality of natural heat dissipation coefficients corresponding thereto are fitted to obtain a first mapping relationship between the calibrated natural heat dissipation coefficient and the calibrated brake plate temperature.

5. The method for determining the brake disc temperature according to claim 4, characterized in that: After fitting the plurality of calibrated brake plate temperatures and the plurality of natural heat dissipation coefficients corresponding thereto to obtain a first mapping relationship between the calibrated natural heat dissipation coefficient and the calibrated brake plate temperature, the calibration method of the first mapping relationship further includes: Starting from the calibrated high temperature limit, the temperature at the next moment is calculated according to the temperature at the previous moment and the natural heat dissipation coefficient corresponding to the temperature in the first mapping relationship, so as to obtain the temperatures at multiple moments and obtain a first simulated cooling curve of the brake disc; The first simulated cooling curve is compared with the first cooling curve, and the first mapping relationship is adjusted and updated.

6. The method for determining the brake disc temperature according to claim 1, characterized in that: Determining the convective heat dissipation power of the brake disc according to the vehicle speed, ambient temperature and convective heat dissipation coefficient after the first moment and before the second moment includes: The convection heat dissipation coefficient is determined according to the vehicle speed after the first moment and before the second moment.

7. The method for determining the brake disc temperature according to claim 6, characterized in that: The determining the convection heat dissipation coefficient according to the vehicle speed after the first moment and before the second moment includes: In a second mapping relationship between a calibrated convection heat dissipation coefficient and a calibrated vehicle speed, the calibrated convection heat dissipation coefficient corresponding to the calibrated vehicle speed that is the same as the vehicle speed is determined as the convection heat dissipation coefficient.

8. The method for determining the brake disc temperature according to claim 7, characterized in that: The calibration method of the second mapping relationship includes: Obtaining a second cooling curve of the temperature of the brake disc decreasing from a calibrated high temperature limit to a calibrated low temperature limit relative to time during the process of the natural heat dissipation and convection heat dissipation of the brake disc when the vehicle is traveling at a constant speed at different calibrated vehicle speeds; wherein different calibrated vehicle speeds correspond to different second cooling curves; Starting from the calibrated high temperature limit, according to the temperature at the previous moment and the corresponding natural heat dissipation coefficient, ambient temperature, specific heat capacity corresponding to the temperature at the previous moment, different calibrated vehicle speeds, and a preset convection heat dissipation coefficient corresponding to the calibrated vehicle speed, the temperature at the next moment is calculated to obtain the temperatures at multiple moments, and obtain multiple second simulated temperature drop curves of the brake disc; Comparing the second simulated cooling curve with the second cooling curve at the same calibrated vehicle speed, updating the preset convection heat dissipation coefficient corresponding to the calibrated vehicle speed, and obtaining the calibrated convection heat dissipation coefficient corresponding to the calibrated vehicle speed; A plurality of the calibrated vehicle speeds and a plurality of the corresponding calibrated convection heat dissipation coefficients are fitted to obtain a second mapping relationship between the calibrated convection heat dissipation coefficients and the calibrated vehicle speeds.

9. The method for determining the brake disc temperature according to claim 8, characterized in that: After fitting the plurality of calibrated vehicle speeds and the plurality of calibrated convection heat dissipation coefficients corresponding thereto to obtain a second mapping relationship between the calibrated convection heat dissipation coefficients and the calibrated vehicle speeds, the calibration method for the second mapping relationship further includes: Obtaining a third temperature drop curve of the temperature of the brake disc decreasing from a calibrated high temperature limit value to a calibrated low temperature limit value relative to time during the process of the vehicle changing speeds at different calibrated vehicle speeds; Starting from the calibrated high temperature limit, the temperature at the next moment is calculated according to the temperature at the previous moment and the corresponding natural heat dissipation coefficient, the ambient temperature, the specific heat capacity corresponding to the temperature at the previous moment, the speed at the previous moment and the convection heat dissipation coefficient corresponding to the speed in the second mapping relationship, and the running state parameter of the vehicle, so as to obtain the temperatures at multiple moments and obtain a third simulated cooling curve of the brake disc; The third simulated cooling curve is compared with the third cooling curve, and the second mapping relationship is adjusted and updated.

10. A brake disc temperature determination system, characterized in that: The system comprises a memory, a processor and a program stored in the memory and executable on the processor, and the processor implements the brake disc temperature determination method according to any one of claims 1 to 9 when executing the program.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a program, and when the program is executed, the method for determining the brake disc temperature according to any one of claims 1 to 9 is implemented.

Images