Control method for torque of electric vehicle on wavy road surface, storage medium, controller and vehicle

Abstract

The invention provides a method for controlling the torque of an electric vehicle on a wavy road surface, a storage medium, a controller and a vehicle, and the method comprises the following steps: obtaining the current state of a vehicle motor, and obtaining whether the state of the road surface on which the vehicle runs is a wavy road or not; when the road surface state is a wavy road, the output torque of a motor is limited, and torque impact of a motor connecting mechanism is reduced; and when a non-wavy road is determined, the motor torque limit is released and the motor is restored to a normal state. According to the invention, detection when the vehicle passes through the wavy road surface can be realized only by using the motor rotating speed signal, and additional road video acquisition equipment does not need to be added; and the output torque upper limit of the motor is controlled to reduce the torque impact of the motor connecting mechanism, so that the motor is prevented from being damaged, and the reliability of the motor is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle control, and in particular to a method for controlling the torque of an electric vehicle on a corrugated road surface, a storage medium, a controller and a vehicle. Background Art

[0002] Electric vehicles refer to vehicles that use power batteries as energy sources and are driven by motors. During the driving process, the smoothness and stability of the vehicle are related to road excitation, including the vehicle's vertical and pitch directions, longitudinal and lateral inputs related to certain road features. Corrugated roads can excite the vehicle's vertical, pitch, longitudinal, roll and lateral responses, especially such bumpy roads with large amplitudes (including road section differences, cracks, bulges, potholes, etc.).

[0003] Corrugated roads can cause the tires of electric vehicles to spin briefly, which can cause the motor to spin at high speed immediately. Then the tires resume contact with the ground, increasing resistance as they contact the road, causing a large deceleration on the motor, causing it to decelerate rapidly.

[0004] Due to the sudden deceleration of the motor, the inertia of the motor will cause a large torque impact on the motor's connection mechanism; at the same time, a large current will pass through the motor instantly in this case, which may cause damage to the motor; the sudden deceleration of the motor will cause greater vibration, which will affect the reliability of the motor.

[0005] Currently, no effective solution has been proposed for the above problems. Summary of the invention

[0006] To solve the above problems, the present invention discloses a method for controlling the torque of an electric vehicle on a wavy road surface, a storage medium, a controller and a vehicle. When the vehicle passes through a wavy road surface, the torque impact of the motor connection mechanism can be reduced, damage to the motor can be avoided, and the reliability of the motor can be improved.

[0007] The specific plan is as follows:

[0008] The first aspect of the present invention provides a method for controlling the torque of an electric vehicle on a corrugated road, comprising the following steps:

[0009] S1. Obtaining the current state of the vehicle motor and whether the road surface on which the vehicle is traveling is a wavy road;

[0010] S2. When the road surface is wavy, the output torque of the motor is limited to reduce the torque impact of the motor connection mechanism; when it is determined to be a non-wavy road, the motor torque limitation is released and restored to a normal state.

[0011] Furthermore, in the step S1, the current state of the vehicle motor is obtained, including: obtaining the working state of the motor through the motor speed and motor torque issued by the motor controller; obtaining whether the road state on which the vehicle is traveling is a wavy road, including: judging whether the vehicle is in a slipping state through the change of the motor speed; judging whether the vehicle is in a gripping state through the change of the motor speed; judging whether it is a wavy road through the slipping and gripping states.

[0012] Furthermore, the slip state refers to that part of the contact surface of the vehicle tire is in an idling state. At this time, the tire will continuously increase the speed of the motor as the accelerator is pressed, and the vehicle will generate lateral slip force, causing the vehicle to move laterally; the grip state refers to that the vehicle tires are fully in contact with the ground. At this time, the tire speed should be that the contact resistance of the ground will drop significantly; the wavy road refers to a road surface composed of a series of undulations and transition areas between the undulations in the horizontal direction. It is used to evaluate the dynamic response and braking performance of the vehicle by simulating the undulations and bumps in real roads.

[0013] Furthermore, in step S2, limiting the output torque of the motor means limiting the maximum output of the motor torque to the maximum torque of the motor × K trq , where K trq is the limit percentage; the normal state means that the output limit of the motor torque is restored to the maximum torque of the motor.

[0014] A second aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the above-mentioned control method is implemented.

[0015] A third aspect of the present invention provides a domain controller, comprising a memory and one or more processors, wherein the memory is used to store one or more programs; when the one or more programs are executed by the one or more processors, the above-mentioned control method is implemented.

[0016] A fourth aspect of the present invention provides a vehicle, comprising the above-mentioned domain controller.

[0017] The beneficial effects of the present invention are:

[0018] The present invention can detect when a vehicle passes through a wavy road surface by simply using a motor speed signal, without adding additional road video acquisition equipment; and controls the output torque upper limit of the motor to reduce the torque impact of the motor connection mechanism, avoid damage to the motor, and improve the reliability of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a flow chart of the control method of the present invention;

[0020] Figure 2 is a flow chart of corrugated road surface detection in the present invention;

[0021] Figure 3 is a schematic diagram of motor torque recovery in the present invention;

[0022] Figure 4 It is a schematic diagram of the structure of the domain controller in the present invention. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] According to one embodiment of the present invention, an embodiment of a method for controlling the torque of an electric vehicle on a wavy road surface is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in an order different from that shown here.

[0025] The method embodiment can be executed in an electronic device or similar computing device in a vehicle including a memory and a processor. For example, Figure 4 As shown, the electronic device of the vehicle may include one or more processors 101 (the processor may include but is not limited to a central processing unit (CPU), a CAN signal processing chip, a microprocessor (MCU), a programmable logic device (FPGA), an artificial intelligence (AI) type processor, etc.) and a memory 103 for storing data. Optionally, the electronic device of the above-mentioned car may also include a transmission device 104 and an input and output device 102 for communication functions. It can be understood by those skilled in the art that Figure 1 The structure shown is for illustration only and does not limit the structure of the electronic device of the vehicle. For example, the electronic device of the vehicle may include more or fewer components than those described in the above structure, or may have a configuration different from that described in the above structure.

[0026] The memory 103 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the method for controlling the torque of an electric vehicle on a wavy road in the embodiment of the present invention. The processor 101 executes various functional applications and data processing by running the computer program stored in the memory 103, that is, the method for controlling the torque of an electric vehicle on a wavy road is realized. The memory 103 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 103 may further include a memory arranged relative to the processor 101, and these memories may be connected to the on-board controller via a network. Examples of the above-mentioned network include, but are not limited to, a LIN network, a CAN network, and a combination thereof.

[0027] The transmission device 104 is used to receive or send data via a network. The above-mentioned network specific example may include using a vehicle communication CAN network. In one example, the transmission device 104 includes a CAN network transceiver (CAN Network Controller), which can be connected to other network devices via the CAN communication protocol so as to communicate with the vehicle network.

[0028] New energy vehicles are driven by drive motors. In the driving process, a reducer is used to directly connect the drive shaft and the wheels, and the reducer is generally a single speed ratio. The external characteristic curve of the drive motor torque output is generally that the maximum torque can be continuously output at low and medium speeds (4000rpm), and the motor output torque will decrease at high speeds (above 4000rpm).

[0029] Since the motor can generate a lot of torque at low and medium speeds, the negative load generated by the road surface on the tire under this condition will cause a large impact on the motor and its connection mechanism. In particular, wavy roads will cause the tires of electric vehicles to idle for a short time, and the tire idling will cause the motor to rotate at high speed immediately; then the tire will resume contact with the ground, and the resistance of the tire contacting the road will increase, which will cause a large deceleration on the motor, and the motor will decelerate rapidly. The inertia of the motor will cause a large torque impact on the motor's connection mechanism.

[0030] In order to alleviate or eliminate the impact of the motor torque of the vehicle on the wavy road surface on the connection structure, there is currently no relevant control method.

[0031] It should be noted that the technical solution of the present application is applicable to the control of new energy two-wheel drive vehicles and four-wheel drive vehicles, wherein new energy two-wheel drive vehicles are not limited to front-wheel drive or rear-wheel drive. The following embodiments of the present application are described in detail using the front-wheel drive situation as an example, in which case the motor torque requested by the vehicle can be considered as the front motor torque requested. It should be understood that the above-mentioned application scenarios and changes in technical terms do not constitute a limitation on the technical solution of the present application.

[0032] The technical solution of the present application is described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] like Figure 1 As shown, the present invention proposes a method for controlling the torque of an electric vehicle on a corrugated road surface, and the control method specifically includes:

[0034] Step S20: Determine whether the motor speed signal is valid;

[0035] Step S21: Determine whether it is a wavy road;

[0036] Step S22: limiting the motor torque;

[0037] Step S23: restoring the motor torque;

[0038] Step S24: End.

[0039] In this embodiment, electric vehicles include new energy vehicles, such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid vehicles, etc. The vehicle data includes but is not limited to the following types of data: motor torque, motor speed, etc., wherein the motor speed data is the real-time motor speed information generated by the motor during movement, which is generally calculated by the motor controller.

[0040] In this embodiment, the logical relationship between the steps is:

[0041] Step S20: Determine whether the motor speed signal is valid. If not, execute step S24: end the logic judgment. If valid, execute step S21: determine whether it is a wavy road; if not, execute step S23: restore the motor torque. If valid, execute step S22: limit the motor torque.

[0042] In this embodiment, step S20: determining whether the motor speed signal is valid

[0043] This step is judged by the state of the motor speed signal sent by the motor controller. When the state of the motor speed signal sent by the motor controller is "valid", the motor speed signal can be considered valid; when the state of the motor speed signal sent by the motor controller is "invalid", the motor speed signal can be considered invalid.

[0044] In this embodiment, step S21: determining whether the road is wavy

[0045] This step determines whether it is a wavy road by the change in the motor speed value.

[0046] like Figure 2 FIG. 1 is a flow chart of the wavy road judgment process of the present invention, including:

[0047] Step S201: Calculate the slip state;

[0048] Step S202: Calculate the grip state;

[0049] Step S203: Determine the wavy road.

[0050] In this embodiment, step S201: calculating the slip state Slip state Specifically, the sample time Δt is used as the judgment period, and the difference Diff between the motor speed at this moment and the motor speed at the previous moment is calculated. motsped , and compare this difference with the slip state limit Slip limitspeed Compare; when the speed difference Diff motsped Greater than the slip state limit Slip limitspeed Slip state state Judged as ON, otherwise judged as slip state Slip state is OFF.

[0051] In this embodiment, step S202: Calculate the grip state Grip state Specifically, the sample time Δt is used as the judgment period, and the difference Diff between the motor speed at this moment and the motor speed at the previous moment is calculated. motsped and compare this difference with the grip limit Grip limitspeed Compare; when the speed difference Diff motsped Less than the grip limit value Grip limitspeed Grip state Judged as ON, otherwise judge the grip state Grip state is OFF.

[0052] In this embodiment, step S203: Undulate the wave path state , specifically: Slip state state Judged as ON and grip state Grip state Judged as ON, and the slip state is Slip state and Grip state Need to determine the time Undulate in the wave road timeIf all the above conditions are met, the wave road is judged as Undulate state Judged as ON; Slip state state Judged as OFF and grip state Grip state Judged as OFF, and the slip state is Slip state To judge the OFF and Grip status state It is judged as OFF and needs to be cancelled in the wave road judgment time Undulate timeng If all the above conditions are met, the wavy road is judged as Undulate. state is OFF.

[0053] In this embodiment, in step S203: the slip state Slip state and Grip state Need to determine the time Undulate in the wave road time Occurs within the range, specifically when the slip state Slip state When there is a change, the countdown starts. The countdown starts at the wave road determination time Undulate time , until the countdown value reaches 0, if the grip state is Grip state There is a change and the slip state is Slip state If the changes are consistent, it can be considered that the slip state Slip state and Grip state Undulate the time to determine the wave road time occurs within the range.

[0054] In this embodiment, step S22: limit the motor torque, through the determination of the wave road in step S21, when the motor torque is within a certain time Mottrq time Undulate the inner wave road state The number of times the state is ON is greater than the set number of times Limit num , then turn on the motor torque limit. After turning on the motor torque limit, the motor torque limit is the motor maximum torque Mottrq max ×A%, where A% is the motor torque limit percentage coefficient.

[0055] In this embodiment, step S23: restore the motor torque, through the determination of the wave road in step S21, when Mottrq time Undulate the inner wave road state If the number of times the state is OFF exceeds the set number, Reset num , the motor torque limit is cancelled and the motor torque is restored.

[0056] In this embodiment, the motor torque is restored in step S23. In the process of restoring the motor torque, torque mutation is prevented and mechanical structure impact is prevented. Specifically, when the restored motor torque in S23 is judged to be valid / activated, the motor torque limit is restored according to the gradient processing and increased to a normal value.

[0057] In this embodiment, the torque gradient processing is performed using the gradient processing rising factor and the gradient falling change time; the specific torque rising gradient processing uses the following formula to restore the motor torque:

[0058] The specific acceleration gradient processing uses the following formula to restore the motor torque:

[0059] T , trq_output =T trq_input +Δt×Factor up

[0060] T trq_output =T , trq_output +Δt×Factor up

[0061] Among them, T trq_output represents the motor torque after gradient processing, T , trq_output Represents the motor torque after a gradient process, T trq_input Indicates the motor limit torque, Δt represents the gradient rise time, Factor up Represents the gradient processing rise factor.

[0062] Specifically, in this embodiment, when the motor torque recovery is determined to be valid / activated in step S23, the motor torque T of the gradient processing is trq_output Increase the motor limit torque by Δt×Factor in each operating cycle up to calculate; when the recovery motor torque is judged to be invalid / not activated, no gradient processing is performed on the motor limit torque.

[0063] like Figure 3 The motor torque recovery schematic diagram shown in the figure shows that the torque recovery in the figure increases a fixed value every Δt time to restore the motor torque until it returns to the normal motor torque.

[0064] An embodiment of the present invention further provides a storage medium, in which a computer program is stored, wherein the computer program is configured to execute the steps in the above-mentioned vehicle control method embodiment when running.

[0065] An embodiment of the present invention further provides a processor, which is configured to run a computer program to execute the steps in any of the above method embodiments.

[0066] An embodiment of the present invention further provides a vehicle, comprising a memory and a processor, wherein the processor is configured to run a computer program to execute the steps in any one of the above method embodiments.

[0067] Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiments and optional implementation modes, and this embodiment will not be described in detail here.

[0068] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0069] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0070] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0071] The units described as separate components may or may not be physically separated, that is, they may be located in one place, or they may be distributed over multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0072] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0073] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0074] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for controlling the torque of an electric vehicle on a corrugated road, characterized in that: The following steps are involved: S1. Obtaining the current state of the vehicle motor and whether the road surface on which the vehicle is traveling is a wavy road; S2. When the road surface is wavy, the output torque of the motor is limited to reduce the torque impact of the motor connection mechanism; when it is determined to be a non-wavy road, the motor torque limitation is released and restored to a normal state.

2. The method for controlling the torque of an electric vehicle on a corrugated road according to claim 1, characterized in that: In the step S1, the current state of the vehicle motor is obtained, including: obtaining the working state of the motor through the motor speed and motor torque issued by the motor controller; obtaining whether the road surface state on which the vehicle is traveling is a wavy road, including: judging whether the vehicle is in a slipping state through the change of the motor speed; judging whether the vehicle is in a gripping state through the change of the motor speed; judging whether it is a wavy road through the slipping and gripping states.

3. The method for controlling the torque of an electric vehicle on a corrugated road according to claim 2, characterized in that: The slip state refers to that part of the contact surface of the vehicle tire is in an idling state. At this time, the tire will continuously increase the speed of the motor as the accelerator is pressed, and the vehicle will generate lateral slip force, causing the vehicle to move laterally; the grip state refers to that the vehicle tire is fully in contact with the ground. At this time, the tire speed should be that the contact resistance of the ground will drop significantly; the wavy road refers to a road surface composed of a series of undulations and transition areas between the undulations in the horizontal direction. It is used to evaluate the dynamic response and braking performance of the vehicle by simulating the undulations and bumps in real roads.

4. The method for controlling torque of an electric vehicle on a corrugated road surface according to claim 1, characterized in that: In step S2, limiting the output torque of the motor means limiting the maximum output of the motor torque to the maximum torque of the motor × K trq , where K trq is the limit percentage; the normal state means that the output limit of the motor torque is restored to the maximum torque of the motor.

5. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor, the control method according to any one of claims 1 to 4 is implemented.

6. A domain controller, characterized in that: It comprises a memory and one or more processors, wherein the memory is used to store one or more programs; when the one or more programs are executed by the one or more processors, the control method as described in any one of claims 1 to 4 is implemented.

7. A vehicle, characterized in that: Includes the domain controller described in claim 6.

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