Protection method of vehicle differential, controller and medium

Abstract

The invention provides a vehicle differential protection method, a controller and a medium, and relates to the technical field of vehicle control. According to the method, the real-time wheel speed difference of wheels at the two ends of a differential and the real-time output torque of a motor are obtained; according to the duration that the real-time wheel speed difference is larger than the wheel speed difference threshold value and the real-time output torque, the real-time accumulated heat of the differential mechanism is determined; and performing torque output limitation on the motor according to the real-time accumulated heat so as to protect the differential mechanism. According to the method, the differential can be effectively protected, and the reliability of the differential is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a protection method, controller and medium for a vehicle differential. Background Art

[0002] With the development of new energy vehicles, the driving modes of vehicles are gradually improved to adapt to various specific driving scenarios, such as track mode, drift mode, etc., so the reliability requirements for vehicle differentials are getting higher and higher.

[0003] In the related art, the reliability of the differential is improved and damage to the differential is avoided mainly through hardware improvement and software protection logic. In terms of hardware improvement, the differential can be protected by selecting a larger differential or enhancing the lubrication capacity of the differential; in terms of software protection logic, differential protection can be achieved through the speed difference between the wheels at the left and right ends of the differential.

[0004] However, the above-mentioned methods are not effective in protecting the differential and cannot guarantee the reliability of the differential. Summary of the invention

[0005] The embodiments of the present application provide a vehicle differential protection method, a controller, and a medium, which can effectively improve the reliability of the differential.

[0006] In a first aspect, an embodiment of the present application provides a method for protecting a vehicle differential, comprising:

[0007] Obtain the real-time wheel speed difference of the wheels at both ends of the differential and the real-time output torque of the motor;

[0008] determining a real-time accumulated heat of the differential according to a duration during which the real-time wheel speed difference is greater than a wheel speed difference threshold value and the real-time output torque;

[0009] The torque output of the motor is limited according to the real-time accumulated heat to protect the differential.

[0010] In a possible implementation manner, determining the real-time accumulated heat of the differential according to the duration of the real-time wheel speed difference being greater than the wheel speed difference threshold and the real-time output torque includes:

[0011] Determining whether the real-time wheel speed difference is greater than a wheel speed difference threshold;

[0012] If it is greater than the wheel speed difference threshold, the heat generated at the current moment is determined according to the real-time wheel speed difference, the preset time difference, and the real-time output torque; the real-time accumulated heat of the differential is determined according to the heat generated at the current moment and the accumulated heat at the previous moment;

[0013] If it is not greater than the wheel speed difference threshold, the real-time accumulated heat of the differential is determined according to the accumulated heat at the last moment.

[0014] In a possible implementation manner, limiting the torque output of the motor according to the real-time accumulated heat includes:

[0015] Determining whether the real-time accumulated heat exceeds a heat threshold, where the heat threshold is a maximum heat allowed for the differential to operate;

[0016] If the thermal threshold is exceeded, limiting the torque output of the motor;

[0017] If the thermal threshold is not exceeded, the torque output of the electric machine is controlled normally.

[0018] In a possible implementation manner, limiting the torque output of the motor includes:

[0019] The output torque of the motor is limited to 0.

[0020] In a possible implementation manner, after limiting the torque output of the motor according to the real-time accumulated heat, the method further includes:

[0021] Obtaining a limiting time for limiting the torque output of the motor;

[0022] Whether to restore normal torque output control of the motor is determined according to the limit time.

[0023] In a possible implementation manner, determining whether to restore normal torque output control of the motor according to the limited time length includes:

[0024] Determine whether the limit time reaches the cooling time, where the cooling time is the duration for the differential to cool from a heat threshold to 0;

[0025] If the cooling time is reached, normal torque output control of the motor is restored;

[0026] If the cooling time has not been reached, the torque output of the motor continues to be limited.

[0027] In a possible implementation manner, obtaining the real-time wheel speed difference of the wheels at both ends of the differential includes:

[0028] Obtain the real-time wheel speed of the wheels at both ends of the differential collected by the wheel speed sensor;

[0029] The real-time wheel speed difference of the wheels at both ends of the differential is determined according to the absolute value of the difference between the real-time wheel speeds of the wheels at both ends of the differential.

[0030] In a second aspect, an embodiment of the present application provides a vehicle controller VCU, comprising:

[0031] An acquisition module is used to acquire the real-time wheel speed difference of the wheels at both ends of the differential and the real-time output torque of the motor;

[0032] A processing module is used to determine the real-time accumulated heat of the differential according to the duration that the real-time wheel speed difference is greater than the wheel speed difference threshold and the real-time output torque; and to limit the torque output of the motor according to the real-time accumulated heat to protect the differential.

[0033] In a third aspect, an embodiment of the present application provides another vehicle controller VCU, including:

[0034] A processor, and a memory communicatively connected to the processor;

[0035] Memory is used to store computer executable instructions;

[0036] The processor is used to execute the computer-executable instructions stored in the memory to implement the vehicle differential protection method of the first aspect.

[0037] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the vehicle differential protection method of the first aspect.

[0038] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, is used to implement the vehicle differential protection method of the first aspect.

[0039] The embodiment of the present application provides a vehicle differential protection method, controller and medium, which can determine the real-time accumulated heat of the differential according to the duration of the real-time wheel speed difference being greater than the wheel speed difference threshold and the real-time output torque of the motor during vehicle driving, and limit the torque output of the motor according to the real-time accumulated heat. Through such a setting, the differential can be protected by the real-time accumulated heat of the differential to avoid damage to the differential caused by various situations. The differential can be protected not only when the wheel speed difference is large, but also when the duration is long or the torque is too large, thereby effectively protecting the vehicle differential in various driving scenarios and improving the reliability of the differential. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] 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.

[0041] Figure 1A system architecture diagram of an embodiment of the present application;

[0042] Figure 2 A flow chart of a method for protecting a vehicle differential according to an embodiment of the present application;

[0043] Figure 3 This is a schematic diagram of the structure of a vehicle controller according to an embodiment of the present application;

[0044] Figure 4 This is a schematic structural diagram of a vehicle controller according to another embodiment of the present application.

[0045] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0046] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0047] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0048] In the technical solution of this application, the collection, storage, use, processing, transmission, provision and disclosure of information such as financial data or user data involved shall comply with the provisions of relevant laws and regulations and shall not violate public order and good morals.

[0049] It should be noted that in the embodiments of the present application, certain software, components, models and other existing solutions in the industry may be mentioned, and they should be regarded as exemplary. Their purpose is only to illustrate the feasibility of implementing the technical solution of the present application, but it does not mean that the applicant has or will necessarily use the solution.

[0050] It should also be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards, and provide corresponding operation entrances for users to choose to authorize or refuse.

[0051] The vehicle differential protection method, controller and medium of the present application can be used in the field of vehicle control technology, and can also be used in any field other than the field of vehicle control technology, such as the field of differential protection, etc. The application field of the vehicle differential protection method, controller and medium of the present application is not limited.

[0052] The vehicle differential protection method, controller and medium of the present application can be applied to scenarios where differential protection is performed during vehicle driving. Any vehicle that has a differential and can collect signals of torque, wheel speed difference and duration can apply the vehicle differential protection method, controller and medium of the present application.

[0053] First, the terms involved in this application are explained:

[0054] The differential is a mechanism that enables the left and right (or front and rear) drive wheels to rotate at different speeds. It is mainly composed of left and right axle gears, two planetary gears and a gear rack. Its function is to make the left and right wheels roll at different speeds when the car is turning or driving on uneven roads, that is, to ensure that the drive wheels at both ends perform pure rolling motion.

[0055] Torque is a special moment that makes an object rotate. The torque of an engine refers to the torque output from the crankshaft end of the engine. Under the condition of fixed power, it is inversely proportional to the engine speed. The faster the speed, the smaller the torque, and vice versa. It reflects the load capacity of the car within a certain range.

[0056] The speed ratio (transmission ratio) of the electric drive system refers to the speed ratio between the motor output shaft and the drive wheel, which directly affects the power performance and efficiency of electric vehicles.

[0057] With the development of new energy vehicles, the driving modes of vehicles are gradually improved to adapt to various specific driving scenarios, such as track mode, drift mode, etc., so the reliability requirements for vehicle differentials are getting higher and higher.

[0058] In the related art, the reliability of the differential is improved and damage to the differential is avoided mainly through hardware improvement and software protection logic. In terms of hardware improvement, the differential can be protected by selecting a larger differential or enhancing the lubrication capacity of the differential; in terms of software protection logic, differential protection can be achieved through the speed difference between the wheels at the left and right ends of the differential.

[0059] However, the above methods are not very effective in protecting the differential and cannot guarantee the reliability of the differential.

[0060] (1) Selecting a larger differential will require more weight and layout space, which cannot meet the requirements of compactness and lightweight. At the same time, it will require more cost and cannot guarantee the reliability of the differential.

[0061] (2) The lubrication capacity of the differential has its limits, and the reliability of the differential cannot be guaranteed.

[0062] (3) In terms of software protection logic, the differential can only be protected in scenarios where the wheel speed difference is large, such as turning and skidding, by using the wheel speed difference between the left and right wheels of the differential. In scenarios where the wheel speed difference is small but lasts for a long time, such as drifting, the differential cannot be well protected and the reliability of the differential cannot be guaranteed.

[0063] Based on the above technical problems, the inventive concept of the present application is to provide a protection scheme for a vehicle differential that can effectively improve the reliability of the differential.

[0064] The embodiments of the present application provide a method, controller and medium for protecting a vehicle differential. It is not necessary to select a larger differential, so as to meet the requirements of compactness and lightweight of the vehicle and to increase the cost. The differential can be effectively protected by accumulating heat of the differential in real time to avoid damage to the differential caused by various situations, thereby effectively protecting the vehicle differential in various driving scenarios and improving the reliability of the differential.

[0065] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0066] Figure 1 This is a system architecture diagram of an embodiment of the present application, such as Figure 1As shown, the vehicle controller VCU is connected to the wheel speed sensors installed on the left and right wheels of the differential to obtain the real-time wheel speeds at the wheels at both ends; the VCU is also connected to the electric drive control system to obtain the real-time output torque of the motor collected by the electric drive control system. The VCU determines the real-time wheel speed difference of the wheels at both ends of the differential based on the real-time wheel speeds at both ends, determines the real-time accumulated heat of the differential based on the duration that the real-time wheel speed difference is greater than the wheel speed difference threshold, and the real-time output torque; and limits the torque output of the motor based on the real-time accumulated heat to protect the differential.

[0067] Figure 2 This is a flow chart of a vehicle differential protection method according to an embodiment of the present application. This embodiment uses a vehicle control unit (VCU) as an execution subject to illustrate the vehicle differential protection method. Figure 2 As shown, the vehicle differential protection method may include the following steps:

[0068] S201: Obtain the real-time wheel speed difference of the wheels at both ends of the differential and the real-time output torque of the motor.

[0069] In this embodiment, the differential can be a differential set on the front axle of the vehicle, or a differential set on the rear axle of the vehicle. The vehicle controller can protect the differentials of the front axle and the rear axle respectively, and the differential protections of the front axle and the rear axle are not related.

[0070] In this embodiment, the wheel speed sensors (WSS) installed on the wheels at the left and right ends of the differential can collect the real-time wheel speeds at the wheels at both ends in real time. The vehicle controller can obtain the real-time wheel speeds collected by the WSS through the CAN bus or wireless communication, and determine the real-time wheel speed difference of the wheels at both ends of the differential through the real-time wheel speeds.

[0071] In this embodiment, the real-time wheel speed difference may be the absolute value of the difference between the real-time wheel speeds of the wheels at both ends of the differential.

[0072] In this embodiment, the electric drive control system (Motor Generator Module, MGM) can collect the output torque of the motor in the electric drive system in real time, and the vehicle controller can obtain the real-time output torque collected by the MGM through the CAN bus or wireless communication.

[0073] S202: Determine the real-time accumulated heat of the differential according to the duration that the real-time wheel speed difference is greater than the wheel speed difference threshold and the real-time output torque.

[0074] In this embodiment, the duration of the real-time wheel speed difference being greater than the wheel speed difference threshold value may be the cumulative duration of the wheel speed difference being greater than the wheel speed difference threshold value during the period from when the vehicle is powered on to the current moment. After the vehicle is powered on, the vehicle controller will obtain the real-time wheel speed difference at each moment, and compare the real-time wheel speed difference with the wheel speed difference threshold value. If the wheel speed difference at a certain moment is not greater than the wheel speed difference threshold value, the duration will not be counted at that moment. If the wheel speed difference at a certain moment is greater than the wheel speed difference threshold value, the duration will be counted at that moment for accumulation.

[0075] In this embodiment, those skilled in the art may flexibly set the wheel speed difference threshold according to requirements. For example, the wheel speed difference threshold may be 20 rpm or 25 rpm, and no limitation is made herein.

[0076] For example, the wheel speed difference of a vehicle is less than 20 rpm within 0-10 minutes after power-on, the wheel speed difference within 10 minutes 1s-5s is 25 rpm, the wheel speed difference within 10 minutes 6s-35s is less than 20 rpm, the wheel speed difference within 10 minutes 36s-40s is 22 rpm, and 10 minutes 40s is the current moment. Then, the duration that the real-time wheel speed difference is greater than the wheel speed difference threshold is 1s-5s and 36s-40s, accumulating 10s.

[0077] S203: Limiting the torque output of the motor according to the real-time accumulated heat to protect the differential.

[0078] In this embodiment, during the driving process of the vehicle, whether the wheel speed difference is too large, the torque is too large, or the drift time is too long, the differential will be overheated and damaged. Therefore, the torque output of the motor can be limited according to the real-time accumulated heat. When the real-time accumulated heat is too large, the torque is limited to avoid damage to the differential, thereby effectively improving the reliability of the differential.

[0079] In this embodiment, during the driving process of the vehicle, the real-time accumulated heat of the differential can be determined according to the duration of the real-time wheel speed difference being greater than the wheel speed difference threshold and the real-time output torque of the motor, and the torque output of the motor can be limited according to the real-time accumulated heat. Through such a setting, the differential can be protected by the real-time accumulated heat of the differential to avoid damage to the differential caused by various situations. The differential can be protected not only when the wheel speed difference is large, but also when the duration is long or the torque is too large, thereby effectively protecting the vehicle differential in various driving scenarios and improving the reliability of the differential.

[0080] In a possible implementation, obtaining the real-time wheel speed difference of the wheels at both ends of the differential in the above step S201 may include:

[0081] S11: acquiring the real-time wheel speeds of the wheels at both ends of the differential collected by the wheel speed sensor;

[0082] S12: Determine the real-time wheel speed difference of the wheels at both ends of the differential according to the absolute value of the difference between the real-time wheel speeds of the wheels at both ends of the differential.

[0083] In this embodiment, the real-time wheel speed difference n delta=left wheel speed n left−right wheel speed n right or right wheel speed n right −left wheel speed n left (n delta>0).

[0084] In this embodiment, after obtaining the real-time wheel speeds of the wheels at both ends collected by the wheel speed sensors, the real-time wheel speed difference of the wheels at both ends of the differential can be simply and accurately determined based on the absolute value of the difference between the real-time wheel speeds of the wheels at both ends.

[0085] In a possible implementation, the above step S202 determines the real-time accumulated heat of the differential according to the duration of the real-time wheel speed difference being greater than the wheel speed difference threshold and the real-time output torque, and may include:

[0086] S21: Determine whether the real-time wheel speed difference is greater than a wheel speed difference threshold.

[0087] S22: If it is greater than the wheel speed difference threshold, the heat generated at the current moment is determined according to the real-time wheel speed difference, the preset time difference, and the real-time output torque; the real-time accumulated heat of the differential is determined according to the heat generated at the current moment and the accumulated heat at the previous moment.

[0088] S23: If the wheel speed difference is not greater than the wheel speed difference threshold, the real-time accumulated heat of the differential is determined according to the accumulated heat at the last moment.

[0089] In this embodiment, after the vehicle is powered on, the vehicle controller will obtain the real-time wheel speed difference at each moment, and compare the real-time wheel speed difference with the wheel speed difference threshold. If the wheel speed difference at a certain moment is not greater than the wheel speed difference threshold, it will not be counted at that moment. If the wheel speed difference at a certain moment is greater than the wheel speed difference threshold, the heat generated at that moment will be calculated and included in the accumulated amount at previous moments.

[0090] In this embodiment, those skilled in the art may flexibly set the wheel speed difference threshold according to requirements. For example, the wheel speed difference threshold may be 20 rpm or 25 rpm, and no limitation is made herein.

[0091] In this embodiment, the heat generated at the current moment can be calculated using the following formula (1):

[0092] Q = Te-motor × S T ×n delta×Δt (1)

[0093] Among them, Te-motor is the real-time output torque at the current moment, ST is the speed ratio of the electric drive system, n delta is the real-time wheel speed difference at the current moment, and Δt is the time difference between the previous moment and the current moment.

[0094] In this embodiment, after the heat at each moment greater than the wheel speed difference threshold is calculated, the heat at each moment is integrated to obtain the real-time accumulated heat of the differential.

[0095] In this embodiment, the speed ratio of the electric drive system refers to the speed ratio between the motor output shaft and the drive wheel, which can be obtained by calibrating the electric drive system. The speed ratio of the electric drive system depends on the hardware capabilities of the electric drive system. For example, the speed ratio of the electric drive system can be 9.19.

[0096] In this embodiment, during the period from vehicle power-on to the current moment, only the heat generated at each moment when the real-time wheel speed difference is greater than the wheel speed difference threshold is calculated, and the wheel speed difference not greater than the wheel speed difference threshold can be considered as a cooling condition and is not included in the heat accumulation. By integrating the heat at each moment greater than the wheel speed difference threshold, the real-time accumulated heat of the differential can be accurately obtained.

[0097] In a possible implementation, limiting the torque output of the motor according to the real-time accumulated heat in step S203 may include:

[0098] S31: Determine whether the real-time accumulated heat exceeds a heat threshold, where the heat threshold is the maximum heat allowed for the differential to operate.

[0099] S32: If the thermal threshold is exceeded, the torque output of the motor is limited.

[0100] S33: If the heat threshold is not exceeded, the torque output of the motor is controlled normally.

[0101] In this embodiment, the heat threshold may be the maximum heat allowed for the differential to work, and exceeding the heat threshold will cause damage to the differential. The heat threshold may be obtained by calibrating the differential using the electric drive system, and the heat threshold depends on the hardware capability of the differential.

[0102] In this embodiment, by comparing the real-time accumulated heat with the heat threshold, it is possible to accurately determine whether the torque output of the motor needs to be limited at the current moment, thereby protecting the differential.

[0103] In a possible implementation, limiting the torque output of the motor in step S22 may include:

[0104] Limit the motor's output torque to 0.

[0105] In this embodiment, when the output torque of the motor is limited to 0, the power of the drive (front drive or rear drive) corresponding to the differential is limited, and only the other drive (rear drive or front drive) is used to provide power.

[0106] Alternatively, the output torque of the motor may be limited to a value close to zero.

[0107] In this embodiment, after the real-time accumulated heat exceeds the heat threshold, the differential can be cooled by limiting the output torque of the motor to 0, thereby preventing the differential from being damaged by overheating, thereby further improving the reliability of the differential.

[0108] In a possible implementation manner, after limiting the torque output of the motor according to the real-time accumulated heat in the above step S203, the following may also be included:

[0109] S41: Obtaining a time limit for limiting the torque output of the motor.

[0110] S42: Determine whether to restore normal torque output control of the motor according to the limit time.

[0111] In this embodiment, the normal torque output control of the motor is restored, and the vehicle controller normally receives the torque request to control the output of the motor, and the electric drive system works normally.

[0112] In this embodiment, after the output torque of the motor is limited to 0, the accumulation of the limit time will be triggered. According to the accumulated limit time, it can be determined whether the differential has cooled down enough to restore the full performance output of the electric drive system, thereby further improving the reliability of the differential.

[0113] In a possible implementation manner, the above step S32 determines whether to restore normal torque output control of the motor according to the limit time, which may include:

[0114] S51: Determine whether the limit time reaches the cooling time, where the cooling time is the duration for the differential to cool from a heat threshold to 0.

[0115] S52: If the cooling time is reached, normal torque output control of the motor is restored.

[0116] S53: If the cooling time has not been reached, the torque output of the motor continues to be limited.

[0117] In this implementation, the cooling time may be obtained by calibrating the differential, and the cooling time depends on the hardware capability of the differential.

[0118] In this embodiment, the cooling time T=Q difference / c difference, Q difference represents the heat threshold of the differential, and c difference represents the amount of heat that can be cooled by the differential per unit time.

[0119] In this embodiment, the cooling time is the duration for the differential to cool from the heat threshold to 0. Therefore, by comparing the time limit for limiting the torque output of the motor with the cooling time, the moment when the motor resumes normal torque output can be determined simply and accurately.

[0120] The vehicle differential protection method of the present application is described below with reference to a specific embodiment.

[0121] In a specific embodiment, after a vehicle is powered on, the vehicle controller of the vehicle protects the vehicle's differential. The specific protection process is as follows:

[0122] In the first step, the wheel speed sensors installed on the wheels at the left and right ends of the differential collect the real-time wheel speeds at the wheels at both ends and transmit the real-time wheel speeds to the vehicle controller; the electric drive control system collects the output torque of the motor in the electric drive system in real time and transmits the real-time output torque to the vehicle controller.

[0123] In the second step, the vehicle controller determines the real-time wheel speed difference of the wheels at both ends of the differential according to the absolute value of the difference between the real-time wheel speeds of the wheels at both ends of the differential.

[0124] In the third step, the vehicle controller determines that the real-time wheel speed difference is greater than the wheel speed difference threshold, and determines the heat generated at the current moment based on the real-time wheel speed difference, time difference, and real-time output torque; and determines the real-time accumulated heat of the differential based on the heat generated at the current moment and the accumulated heat at the previous moment.

[0125] In the fourth step, the vehicle controller determines that the real-time accumulated heat at time A exceeds the heat threshold and limits the output torque of the motor to 0.

[0126] In the fifth step, the vehicle controller obtains the limit time for limiting the torque output of the motor, determines that the limit time at time B reaches the cooling time, and restores normal torque output control of the motor.

[0127] Figure 3 FIG. 1 is a schematic diagram of the structure of a vehicle controller VCU according to an embodiment of the present application. Figure 3 As shown, the vehicle controller includes: an acquisition module 31, which is used to obtain the real-time wheel speed difference of the wheels at both ends of the differential, and the real-time output torque of the motor; a processing module 32, which is used to determine the real-time accumulated heat of the differential according to the duration that the real-time wheel speed difference is greater than the wheel speed difference threshold, and the real-time output torque; and limit the torque output of the motor according to the real-time accumulated heat to protect the differential.

[0128] The vehicle controller provided in the embodiment of the present application can execute the technical solution shown in the above method embodiment, and its implementation principle and beneficial effects are similar, which will not be repeated here.

[0129] In a possible implementation, the acquisition module 31 may also be used to:

[0130] Obtain the real-time wheel speed of the wheels at both ends of the differential collected by the wheel speed sensor;

[0131] The real-time wheel speed difference of the wheels at both ends of the differential is determined according to the absolute value of the difference between the real-time wheel speeds of the wheels at both ends of the differential.

[0132] The vehicle controller provided in the embodiment of the present application can execute the technical solution shown in the above method embodiment, and its implementation principle and beneficial effects are similar, which will not be repeated here.

[0133] In a possible implementation, the processing module 32 may also be used to:

[0134] Determine whether the real-time wheel speed difference is greater than the wheel speed difference threshold;

[0135] If it is greater than the wheel speed difference threshold, the heat generated at the current moment is determined according to the real-time wheel speed difference, the preset time difference, and the real-time output torque; the real-time accumulated heat of the differential is determined according to the heat generated at the current moment and the accumulated heat at the previous moment;

[0136] If it is not greater than the wheel speed difference threshold, the real-time accumulated heat of the differential is determined based on the accumulated heat at the previous moment.

[0137] The vehicle controller provided in the embodiment of the present application can execute the technical solution shown in the above method embodiment, and its implementation principle and beneficial effects are similar, which will not be repeated here.

[0138] In a possible implementation, the processing module 32 may also be used to:

[0139] Determine whether the real-time accumulated heat exceeds a heat threshold, where the heat threshold is the maximum heat allowed for the differential to operate;

[0140] If the thermal threshold is exceeded, the motor’s torque output is limited;

[0141] If the thermal threshold is not exceeded, the torque output of the motor is controlled normally.

[0142] The vehicle controller provided in the embodiment of the present application can execute the technical solution shown in the above method embodiment, and its implementation principle and beneficial effects are similar, which will not be repeated here.

[0143] In a possible implementation, the processing module 32 may also be used to:

[0144] Limit the motor's output torque to 0.

[0145] The vehicle controller provided in the embodiment of the present application can execute the technical solution shown in the above method embodiment, and its implementation principle and beneficial effects are similar, which will not be repeated here.

[0146] In a possible implementation, after limiting the torque output of the motor according to the real-time accumulated heat, the processing module 32 may also be used to:

[0147] Get the time limit for limiting the motor's torque output;

[0148] Whether to restore normal torque output control of the motor is determined according to the restriction time.

[0149] The vehicle controller provided in the embodiment of the present application can execute the technical solution shown in the above method embodiment, and its implementation principle and beneficial effects are similar, which will not be repeated here.

[0150] In a possible implementation, the processing module 32 may also be used to:

[0151] Determine whether the limit time reaches the cooling time, where the cooling time is the duration for the differential to cool from the heat threshold to 0;

[0152] If the cooling time is reached, normal torque output control of the motor is restored;

[0153] If the cooling time is not reached, the torque output of the motor will continue to be limited.

[0154] The vehicle controller provided in the embodiment of the present application can execute the technical solution shown in the above method embodiment, and its implementation principle and beneficial effects are similar, which will not be repeated here.

[0155] Figure 4 This is a schematic diagram of the structure of a vehicle controller according to another embodiment of the present application. Figure 4 As shown, the vehicle controller includes: a processor 401, and a memory 402 that is communicatively connected to the processor 401; the memory 402 stores computer-executable instructions; the processor 401 executes the computer-executable instructions stored in the memory 402 to implement the steps of the vehicle differential protection method in the above-mentioned method embodiments.

[0156] In the above vehicle controller, the memory 402 and the processor 401 are electrically connected directly or indirectly to realize data transmission or interaction. For example, these elements can be electrically connected to each other through one or more communication buses or signal lines, such as through a bus connection. The memory 402 stores computer-executable instructions for implementing the data access control method, including at least one software function module that can be stored in the memory 402 in the form of software or firmware. The processor 401 executes various functional applications and data processing by running the software programs and modules stored in the memory 402.

[0157] The memory 402 may be, but is not limited to, a random access memory (RAM), a read only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electric erasable programmable read-only memory (EEPROM), etc. The memory 402 is used to store programs, and the processor 401 executes the programs after receiving the execution instruction. Furthermore, the software programs and modules in the above-mentioned memory 402 may also include an operating system, which may include various software components and / or drivers for managing system tasks (such as memory management, storage device control, power management, etc.), and may communicate with various hardware or software components to provide an operating environment for other software components.

[0158] The processor 401 may be an integrated circuit chip having the ability to process signals. The processor 401 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc. The methods, steps, and logic diagrams disclosed in the embodiments of the present application may be implemented or executed. The general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0159] An embodiment of the present application further provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the steps of each method embodiment of the present application.

[0160] An embodiment of the present application further provides a computer program product, including a computer program, which implements the steps of each method embodiment of the present application when executed by a processor.

[0161] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required by the present application.

[0162] It should be further noted that, although the various steps in the flow chart are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flow chart may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0163] It should be understood that the above-mentioned device embodiments are only illustrative, and the device of the present application can also be implemented in other ways. For example, the division of units / modules in the above-mentioned embodiments is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units, modules or components can be combined, or can be integrated into another system, or some features can be ignored or not executed.

[0164] In addition, unless otherwise specified, each functional unit / module in each embodiment of the present application may be integrated into one unit / module, each unit / module may exist physically separately, or two or more units / modules may be integrated together. The above-mentioned integrated unit / module may be implemented in the form of hardware or in the form of a software program module.

[0165] In the above embodiments, the description of each embodiment has its own emphasis. For the part not described in detail in a certain embodiment, please refer to the relevant description of other embodiments. The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0166] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes 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 appended claims.

[0167] 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 protecting a vehicle differential, characterized in that: include: Obtain the real-time wheel speed difference of the wheels at both ends of the differential and the real-time output torque of the motor; determining a real-time accumulated heat of the differential according to a duration during which the real-time wheel speed difference is greater than a wheel speed difference threshold value and the real-time output torque; The torque output of the motor is limited according to the real-time accumulated heat to protect the differential.

2. The vehicle differential protection method according to claim 1, characterized in that: Determining the real-time accumulated heat of the differential according to the duration of the real-time wheel speed difference being greater than the wheel speed difference threshold and the real-time output torque includes: Determining whether the real-time wheel speed difference is greater than a wheel speed difference threshold; If it is greater than the wheel speed difference threshold, the heat generated at the current moment is determined according to the real-time wheel speed difference, the preset time difference, and the real-time output torque; the real-time accumulated heat of the differential is determined according to the heat generated at the current moment and the accumulated heat at the previous moment; If it is not greater than the wheel speed difference threshold, the real-time accumulated heat of the differential is determined according to the accumulated heat at the last moment.

3. The vehicle differential protection method according to claim 2, characterized in that: The step of limiting the torque output of the motor according to the real-time accumulated heat comprises: Determining whether the real-time accumulated heat exceeds a heat threshold, where the heat threshold is a maximum heat allowed for the differential to operate; If the thermal threshold is exceeded, limiting the torque output of the motor; If the thermal threshold is not exceeded, the torque output of the electric machine is controlled normally.

4. The vehicle differential protection method according to claim 3, characterized in that: The step of limiting the torque output of the motor comprises: The output torque of the motor is limited to 0.

5. The vehicle differential protection method according to any one of claims 1 to 4, characterized in that: After limiting the torque output of the motor according to the real-time accumulated heat, the method further includes: Obtaining a limiting time for limiting the torque output of the motor; Whether to restore normal torque output control of the motor is determined according to the limit time.

6. The vehicle differential protection method according to claim 5, characterized in that: The determining whether to restore normal torque output control of the motor according to the limited time length includes: Determine whether the limit time reaches the cooling time, where the cooling time is the duration for the differential to cool from a heat threshold to 0; If the cooling time is reached, normal torque output control of the motor is restored; If the cooling time has not been reached, the torque output of the motor continues to be limited.

7. The vehicle differential protection method according to any one of claims 1 to 4, characterized in that: The step of obtaining the real-time wheel speed difference of the wheels at both ends of the differential includes: Obtain the real-time wheel speed of the wheels at both ends of the differential collected by the wheel speed sensor; The real-time wheel speed difference of the wheels at both ends of the differential is determined according to the absolute value of the difference between the real-time wheel speeds of the wheels at both ends of the differential.

8. A vehicle controller VCU, characterized in that: include: An acquisition module is used to acquire the real-time wheel speed difference of the wheels at both ends of the differential and the real-time output torque of the motor; A processing module is used to determine the real-time accumulated heat of the differential according to the duration that the real-time wheel speed difference is greater than the wheel speed difference threshold and the real-time output torque; and to limit the torque output of the motor according to the real-time accumulated heat to protect the differential.

9. A vehicle controller VCU, characterized in that: include: A processor, and a memory communicatively connected to the processor; The memory is used to store computer-executable instructions; The processor is used to execute the computer-executable instructions stored in the memory to implement the vehicle differential protection method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are executed by a processor, they are used to implement the vehicle differential protection method according to any one of claims 1 to 7.

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