Anti-slip control method, device, equipment and storage medium

Abstract

The present invention relates to the field of vehicle control technology, and discloses an anti-slip control method, device, equipment and storage medium. During the vehicle coasting or braking process, it is determined whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed difference; when the vehicle is in a skidding state, the torque to be adjusted is obtained; when the current vehicle speed is greater than or equal to the vehicle speed threshold, according to the slip ratio and the energy recovery value, a torque adjustment ratio is obtained; the torque to be adjusted is adjusted according to the torque adjustment ratio to obtain the execution torque; the execution torque is sent to the motor controller, and the motor controller is used to control the motor to work according to the execution torque, so as to automatically judge the skidding state by the vehicle control unit and quickly adjust the torque according to the skidding state judgment result. The VCM does not need to wait for the vehicle skidding judgment result and torque adjustment request of the VDC, and realizes fast anti-slip control.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle control, and particularly to an anti-slip control method, device, equipment and storage medium. Background Art

[0002] The existing vehicle state, coasting or anti-slip control during braking is in the Vehicle Dynamics Control (VDC) controller. The VDC needs to develop the matching of the braking forces of the four wheels according to the vehicle weight, braking system and other states of the vehicle, and various environmental road surfaces and three-high experiment calibrations are required. The development cycle is long and the cost is high. Due to different vehicle states, each vehicle model needs to be newly developed. If the motor system of the vehicle changes, the VDC also needs to perform corresponding matching development, incurring high development costs.

[0003] After the VDC system determines that the vehicle is slipping, it sends information to the Vehicle Control Module (VCM). After the VCM arbitrates information such as the driver's intention and vehicle state, it sends the calculated execution torque value to the motor controller for execution. The control link is long. From the start of vehicle slipping to the execution of anti-slip control, the required cycle is relatively long, and the vehicle slipping cannot be corrected in the first time. If the control strategy is slightly deviated, it will bring an obvious sense of impact to the vehicle, the driving performance score is poor, and it will also bring driving hazards when on the ice roadside. Summary of the Invention

[0004] The main purpose of the present invention is to propose an anti-slip control method, device, equipment and storage medium, aiming to solve how to more effectively achieve fast anti-slip control.

[0005] To achieve the above object, the present invention provides an anti-slip control method, and the anti-slip control method includes the following steps:

[0006] During the coasting or braking process of the vehicle, determine whether the vehicle is in a slipping state according to the slip ratio or the difference in wheel speeds of the front and rear wheels;

[0007] When the vehicle is in a slipping state, obtain the torque to be adjusted;

[0008] When the current vehicle speed is greater than or equal to the vehicle speed threshold, obtain a torque adjustment ratio according to the slip ratio and the energy recovery value;

[0009] Adjust the torque to be adjusted according to the torque adjustment ratio to obtain an execution torque;

[0010] Send the execution torque to the motor controller, and control the motor to work according to the execution torque through the motor controller.

[0011] Optionally, determining whether the vehicle is in a skidding state according to the slip ratio includes:

[0012] When the current vehicle speed is greater than or equal to the vehicle speed threshold, obtain the front wheel speed and the rear wheel speed of the vehicle;

[0013] Obtain the slip ratio according to the front wheel speed and the rear wheel speed;

[0014] When the slip ratio is greater than or equal to the slip ratio threshold, determine that the vehicle is in a skidding state.

[0015] Optionally, obtaining the slip ratio according to the front wheel speed and the rear wheel speed includes:

[0016] When the vehicle is a front-wheel drive vehicle, obtain the first difference between the rear wheel speed and the front wheel speed;

[0017] Obtain the slip ratio according to the first difference and the rear wheel speed;

[0018] When the vehicle is a rear-wheel drive vehicle, obtain the second difference between the front wheel speed and the rear wheel speed;

[0019] Obtain the slip ratio according to the second difference and the front wheel speed.

[0020] Optionally, determining whether the vehicle is in a skidding state according to the front and rear wheel speed differences includes:

[0021] When the current vehicle speed is less than the vehicle speed threshold, obtain the front wheel speed and the rear wheel speed of the vehicle;

[0022] Obtain the front and rear wheel speed difference according to the front wheel speed and the rear wheel speed;

[0023] When the front and rear wheel speed difference is greater than or equal to the wheel speed threshold, determine that the vehicle is in a skidding state.

[0024] Optionally, obtaining the front and rear wheel speed difference according to the front wheel speed and the rear wheel speed includes:

[0025] When the vehicle is a front-wheel drive vehicle, subtract the front wheel speed from the rear wheel speed to obtain the front and rear wheel speed difference;

[0026] When the vehicle is a rear-wheel drive vehicle, subtract the rear wheel speed from the front wheel speed to obtain the front and rear wheel speed difference.

[0027] Optionally, determining whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed differences includes:

[0028] Obtain the gear signal;

[0029] When the gear signal is a forward gear signal, the signal indicating that the accelerator pedal is depressed is not detected, the slip ratio is greater than or equal to the slip ratio threshold, or the difference between the front and rear wheel speeds is greater than or equal to the wheel speed threshold, it is determined that the vehicle is in a skidding state.

[0030] Optionally, before determining whether the vehicle is in a skidding state according to the slip ratio or the difference between the front and rear wheel speeds during vehicle coasting or braking, it includes:

[0031] Set the priorities of the anti-skid control torque and the driver intention torque, so that the priority of the anti-skid control torque is greater than the priority of the driver intention torque;

[0032] When the vehicle is in a skidding state, obtaining the torque to be adjusted includes:

[0033] When the vehicle is in a skidding state, obtain the anti-skid control torque and the driver intention torque;

[0034] According to the priorities of the anti-skid control torque and the driver intention torque, mask the driver intention torque, and use the anti-skid control torque as the torque to be adjusted.

[0035] Optionally, after obtaining the torque to be adjusted when the vehicle is in a skidding state, it further includes:

[0036] When the current vehicle speed is less than the vehicle speed threshold, obtain the execution torque of the previous cycle;

[0037] Adjust the execution torque of the previous cycle to a preset torque, and use the preset torque as the execution torque.

[0038] Optionally, when the current vehicle speed is greater than or equal to the vehicle speed threshold, obtaining the torque adjustment ratio according to the slip ratio and the energy recovery value includes:

[0039] When the current vehicle speed is greater than or equal to the vehicle speed threshold, query the torque adjustment ratio table according to the slip ratio and the energy recovery value to obtain the torque adjustment ratio, where the torque adjustment ratio table records the corresponding relationships among the slip ratio, the energy recovery value, and the torque adjustment ratio.

[0040] Optionally, before obtaining the torque adjustment ratio according to the slip ratio and the energy recovery value when the current vehicle speed is greater than or equal to the vehicle speed threshold, it further includes:

[0041] Obtain the current vehicle speed, the current braking torque, the motor operating state, and the battery operating state;

[0042] Determine the energy recovery value according to the current vehicle speed, the current braking torque, the motor operating state, and the battery operating state.

[0043] Optionally, adjusting the torque to be adjusted according to the torque adjustment ratio to obtain an execution torque includes:

[0044] Obtaining a theoretical target torque according to the torque to be adjusted and the torque adjustment ratio;

[0045] Dividing an adjustment period into a plurality of time periods according to the theoretical target torque;

[0046] Determining the theoretical target torques corresponding to the plurality of time periods;

[0047] Determining a torque rising rate and an execution torque for the next period according to the theoretical target torques corresponding to the plurality of time periods;

[0048] Gradually increasing the torque to be adjusted according to the torque rising rate and the execution torque until the adjusted torque reaches the theoretical target torque of the corresponding period.

[0049] Optionally, determining the theoretical target torques corresponding to the plurality of time periods includes:

[0050] Real-time monitoring of changes in the slip ratio and the energy recovery value;

[0051] When the torque adjustment ratio corresponding to the changed slip ratio and energy recovery value changes, determining the theoretical target torques corresponding to the plurality of time periods according to the new torque adjustment ratio.

[0052] Optionally, after the adjusted torque reaches the theoretical target torque of the corresponding period, it further includes:

[0053] Exiting the anti-skid control strategy and switching the anti-skid control torque to the driver's intended torque;

[0054] Within the current period, obtaining a target torque according to the driver's intended torque and the current torque when exiting the anti-skid control strategy;

[0055] Obtaining an output torque according to the target torque, the filtering coefficient, and the current torque;

[0056] Sending the output torque to the motor controller, and controlling the motor to work according to the output torque through the motor controller;

[0057] Within the next period, obtaining a next-period output torque according to the target torque, the filtering coefficient, and the output torque;

[0058] Sending the next-period output torque to the motor controller, and controlling the motor to work according to the next-period output torque through the motor controller until the output torque reaches the target torque.

[0059] In addition, to achieve the above object, the present invention further provides an anti-slip control device, which includes:

[0060] An acquisition module, configured to determine whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed difference during the vehicle coasting or braking process;

[0061] The acquisition module is further configured to obtain an adjustable torque when the vehicle is in a skidding state;

[0062] The acquisition module is further configured to obtain a torque adjustment ratio according to the slip ratio and the energy recovery value when the current vehicle speed is greater than or equal to the vehicle speed threshold;

[0063] An adjustment module, configured to adjust the adjustable torque according to the torque adjustment ratio to obtain an execution torque;

[0064] A control module, configured to send the execution torque to a motor controller, and control the motor to work according to the execution torque through the motor controller.

[0065] In addition, to achieve the above object, the present invention further provides an anti-slip control device, which includes: a memory, a processor, and an anti-slip control program stored on the memory and executable on the processor, and the anti-slip control program is configured to implement the anti-slip control method as described above.

[0066] In addition, to achieve the above object, the present invention further provides a storage medium, on which an anti-slip control program is stored, and when the anti-slip control program is executed by a processor, it implements the anti-slip control method as described above.

[0067] The anti-slip control method provided by the present invention determines whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed difference during the vehicle coasting or braking process; obtains an adjustable torque when the vehicle is in a skidding state; obtains a torque adjustment ratio according to the slip ratio and the energy recovery value when the current vehicle speed is greater than or equal to the vehicle speed threshold; adjusts the adjustable torque according to the torque adjustment ratio to obtain an execution torque; sends the execution torque to a motor controller, and controls the motor to work according to the execution torque through the motor controller, so as to automatically judge the skidding state through VCM, and quickly adjust the torque according to the skidding state judgment result. VCM does not need to wait for the vehicle skidding judgment result and torque adjustment request of VDC. After VCM independently judges that the vehicle is skidding, it quickly performs skidding correction control and quickly requests the motor to execute, realizing fast anti-slip control. Description of the Drawings

[0068] Figure 1It is a schematic structural diagram of an anti-slip control device for the hardware operating environment involved in the embodiment solution of the present invention;

[0069] Figure 2 It is a schematic flowchart of the first embodiment of the anti-slip control method of the present invention;

[0070] Figure 3 It is a schematic flowchart of the second embodiment of the anti-slip control method of the present invention;

[0071] Figure 4 It is a schematic diagram of the functional modules of the first embodiment of the anti-slip control device of the present invention.

[0072] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Detailed Embodiment

[0073] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0074] Refer to Figure 1 , Figure 1 It is a schematic structural diagram of the device for the hardware operating environment involved in the embodiment solution of the present invention.

[0075] As shown in Figure 1 , the device may include: a processor 1001, such as a CPU, a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Among them, the communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a display screen (Display) and an input unit such as a button. Optionally, the user interface 1003 may further include a standard wired interface and a wireless interface. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a Wi-Fi interface). The memory 1005 may be a high-speed RAM memory or a stable memory (non-volatile memory), such as a disk memory. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0076] Those skilled in the art can understand that Figure 1 the anti-slip control device structure shown in

[0077] does not constitute a limitation on the anti-slip control device and may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0077] As shown in Figure 1 , the memory 1005, as a storage medium, may include an operating system, a network communication module, a user interface module, and an anti-slip control program.

[0078] In Figure 1In the anti-skid control device shown, the network interface 1004 is mainly used to connect to a server and communicate data with the server; the user interface 1003 is mainly used to connect to a user terminal and communicate data with the terminal; the anti-skid control device of the present invention calls the anti-skid control program stored in the memory 1005 through the processor 1001 and executes the anti-skid control method provided by the embodiments of the present invention.

[0079] Based on the above hardware structure, an embodiment of the anti-skid control method of the present invention is proposed.

[0080] Refer to Figure 2 , Figure 2 which is a schematic flow chart of the first embodiment of the anti-skid control method of the present invention.

[0081] In the first embodiment, the anti-skid control method includes the following steps:

[0082] Step S10, during the vehicle coasting or braking process, determine whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed difference.

[0083] It should be noted that the execution subject of this embodiment is the VCM. There is an anti-skid control program on the VCM, which can automatically perform anti-skid control according to the anti-skid control program. In general, the VDC judges whether the vehicle is coasting or braking and skidding according to the gear information, vehicle speed signal, wheel speed signal, and accelerator pedal signal and brake pedal signal, and then the VCM calculates the execution torque according to the vehicle skidding judgment result and torque adjustment request of the waiting VDC, resulting in a long control link and unable to perform anti-skid control in time. Therefore, in this embodiment, the vehicle coasting or braking skidding judgment is set on the VCM, and the VCM is used to judge whether the vehicle is coasting or braking and skidding, without waiting for the skidding judgment result of the VDC, effectively shortening the anti-skid control link.

[0084] A specific implementation example is provided. Determine whether the vehicle is in a skidding state according to the slip ratio. When the current vehicle speed is greater than or equal to the vehicle speed threshold, obtain the front wheel speed and rear wheel speed of the vehicle; obtain the slip ratio according to the front wheel speed and rear wheel speed; when the slip ratio is greater than or equal to the slip ratio threshold, determine that the vehicle is in a skidding state.

[0085] It should be noted that at low speeds, the front and rear wheel speeds are both relatively low, and there is a slight difference between the front and rear wheel speeds. Using the calculation method of slip ratio is likely to cause misjudgment. Therefore, when judging vehicle coasting or braking skidding, the vehicle speed signal is added as a threshold condition for distinguishing vehicle coasting or braking skidding. When the vehicle speed is greater than or equal to the vehicle speed threshold, the slip ratio is used for skidding judgment. When the vehicle speed is less than the vehicle speed threshold, the front and rear wheel speed difference is used for skidding judgment, thereby improving the accuracy of vehicle coasting or braking skidding judgment. The vehicle speed threshold can be 5 km / h, or it can be other parameters. This embodiment does not limit this. In this embodiment, only 5 km / h is used as an example of the vehicle speed threshold for illustration. The slip ratio threshold can be 0.08, or it can be other parameters. This embodiment does not limit this. In this embodiment, only 0.08 is used as an example of the slip ratio threshold for illustration.

[0086] In this embodiment, the specific way to obtain the slip ratio according to the front wheel speed and the rear wheel speed is as follows: when the vehicle is a front-wheel drive vehicle, obtain the first difference between the rear wheel speed and the front wheel speed; obtain the slip ratio according to the first difference and the rear wheel speed; when the vehicle is a rear-wheel drive vehicle, obtain the second difference between the front wheel speed and the rear wheel speed; obtain the slip ratio according to the second difference and the front wheel speed. Since during the vehicle coasting or braking process, when the vehicle speed is greater than or equal to the vehicle speed threshold and the vehicle is a front-wheel drive vehicle, the rear wheel speed is equivalent to the actual vehicle speed of the vehicle, and the ratio of the first difference between the rear wheel speed and the front wheel speed to the rear wheel speed is used to obtain the slip ratio, thereby realizing the skidding judgment of the front-wheel drive vehicle through the ratio of the difference between the rear wheel speed and the front wheel speed to the actual vehicle speed. Correspondingly, when performing the skidding judgment of the rear-wheel drive vehicle, since the front wheel speed is equivalent to the actual vehicle speed of the vehicle, the ratio of the second difference between the front wheel speed and the rear wheel speed to the front wheel speed is used to obtain the slip ratio, thereby improving the accuracy of vehicle skidding judgment.

[0087] In the specific implementation, taking W f to represent the front wheel speed and W r to represent the rear wheel speed as an example for illustration, when the vehicle is a front-wheel drive vehicle, the slip ratio is (W r - W f ) / W r . When the vehicle is a rear-wheel drive vehicle, the slip ratio is (W f - W r ) / W f , thereby obtaining an accurate slip ratio.

[0088] Another specific implementation example is provided. Whether the vehicle is in a skidding state is determined based on the difference in rotational speeds between the front and rear wheels. When the current vehicle speed is less than the vehicle speed threshold, the rotational speeds of the front and rear wheels of the vehicle are obtained; the difference in rotational speeds between the front and rear wheels is obtained based on the rotational speeds of the front and rear wheels; when the difference in rotational speeds between the front and rear wheels is greater than or equal to the first rotational speed threshold, it is determined that the vehicle is in a skidding state.

[0089] It should be noted that the first rotational speed threshold can be 60 rpm, or it can be other parameters. This embodiment does not limit this. In this embodiment, only 60 rpm is taken as an example of the first rotational speed threshold for illustration. That is, when the difference in rotational speeds between the front and rear wheels is greater than or equal to 60 rpm, it is determined that the vehicle is in a skidding state, so as to realize the skidding judgment of the vehicle through the difference in rotational speeds between the front and rear wheels.

[0090] Based on the same principle above, when obtaining the difference in rotational speeds between the front and rear wheels according to the rotational speeds of the front and rear wheels, it is also necessary to first determine whether the vehicle is a front-wheel drive vehicle or a rear-wheel drive vehicle. When the vehicle is a front-wheel drive vehicle, the rotational speed of the rear wheel is subtracted from the rotational speed of the front wheel to obtain the difference in rotational speeds between the front and rear wheels; when the vehicle is a rear-wheel drive vehicle, the rotational speed of the front wheel is subtracted from the rotational speed of the rear wheel to obtain the difference in rotational speeds between the front and rear wheels. For example, for a front-wheel drive vehicle, the difference in rotational speeds between the front and rear wheels is W r -W f , and for a rear-wheel drive vehicle, the difference in rotational speeds between the front and rear wheels is W f -W r , thus avoiding misjudgment of the calculation result and improving the accuracy of skidding judgment.

[0091] Step S20, when the vehicle is in a skidding state, obtain the torque to be adjusted.

[0092] It should be noted that the torque to be adjusted is the execution torque of the previous cycle. In this embodiment, an input torque will be set. By recording the execution torque of the previous cycle as the input torque of the current cycle, when it is determined that the vehicle is in a skidding state, the flag position of the anti-skid control torque will be set to valid, thereby shielding the driver's intended torque and realizing the arbitration between the skidding control torque and the driver's intended torque.

[0093] In a specific implementation, by setting the priorities of the anti-skid control torque and the driver's intended torque, the priority of the anti-skid control torque is made greater than the priority of the driver's intended torque. When the vehicle is in a skidding state, the anti-skid control torque and the driver's intended torque are obtained; according to the priorities of the anti-skid control torque and the driver's intended torque, the driver's intended torque is shielded, and the anti-skid control torque is used as the torque to be adjusted.

[0094] It can be understood that when making a skid judgment, in addition to combining the slip ratio and the front and rear wheel speed differences, other parameters can be further referenced to improve the accuracy of the skid judgment. Therefore, the skid judgment can also be made by combining the gear signal and the accelerator pedal signal, that is, by obtaining the gear signal; when the gear signal is a forward gear signal and no accelerator pedal depression signal is detected, that is, the accelerator pedal is released, the slip ratio is greater than or equal to the slip ratio threshold, or the front and rear wheel speed difference is greater than or equal to the wheel speed threshold, it is determined that the vehicle is in a skid state. The slip ratio is greater than or equal to the threshold of 0.08, and this slip ratio threshold can be calibrated and is applicable to vehicle speeds greater than or equal to 5 km / h; or the front and rear wheel speed difference is greater than the threshold of 60 rpm, and this front and rear wheel speed difference threshold can be calibrated and is applicable to vehicle speeds less than 5 km / h. When the above conditions are met and the duration is 0.05 s, and this duration can be calibrated, it is determined that the vehicle is in a skid state.

[0095] When the above conditions are met, it is judged that the vehicle is in a skid state, and the vehicle skid control mode is entered. The vehicle skid control flag position is valid, and arbitration is performed between the skid control torque and the driver's intended torque. At this time, the driver demand torque derived from the APO opening will be masked by the vehicle skid control torque with a higher priority, thus realizing effective torque arbitration.

[0096] Step S30, when the current vehicle speed is greater than or equal to the vehicle speed threshold, obtain the torque adjustment ratio according to the slip ratio and the energy recovery value.

[0097] It should be noted that the torque control strategy includes a high-speed torque control strategy and a low-speed torque control strategy. When the vehicle is at a low vehicle speed, torque control is performed through the low-speed torque control strategy. When the vehicle is at a high vehicle speed, torque control is performed through the high-speed torque control strategy. When performing torque control through the high-speed torque control strategy, obtain the torque adjustment ratio according to the slip ratio and the energy recovery value.

[0098] Step S40, adjust the torque to be adjusted according to the torque adjustment ratio to obtain the execution torque.

[0099] In a specific implementation, when the low-speed torque control strategy performs torque control, the execution torque of the previous cycle is used as the torque to be adjusted and directly adjusted to 0 Nm. When the high-speed torque control strategy performs torque control, a look-up table is performed based on the slip ratio and the energy recovery value to obtain the torque adjustment ratio. Since during the vehicle coasting or braking process, the current torque is a relatively large negative value, when performing torque adjustment, it is a process of gradient increase according to the torque adjustment ratio, that is, the current slip ratio and the energy recovery value are used as two inputs to look up a two-dimensional table, and this table has undergone in-vehicle tests on the road surface. According to different slip ratios and different energy recovery values, different torque gradient adjustment ratios are obtained, and the target torque is adjusted and increased to the target torque according to this ratio. For example, at the moment before anti-skid control, the torque is -A Nm, and the current anti-skid control is activated. Looking up the two-dimensional table, the adjustment ratio is f1. Then the calculated target torque is increased to -A*f1 Nm. Compared with obtaining the target torque by looking up the table based on the slip ratio, using the slip ratio and the energy recovery value as the input items for looking up the two-dimensional table improves the accuracy of torque control, and performs torque control through the torque adjustment ratio instead of directly adjusting the torque through the target torque obtained by looking up the table, making the torque increase process of the vehicle smoother and also improving the driving experience of the driver.

[0100] Step S50: Send the execution torque to the motor controller, and control the motor to work according to the execution torque through the motor controller.

[0101] In this embodiment, during the vehicle coasting or braking process, it is determined whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed difference; when the vehicle is in a skidding state, the torque to be adjusted is obtained; when the current vehicle speed is greater than or equal to the vehicle speed threshold, the torque adjustment ratio is obtained according to the slip ratio and the energy recovery value; the torque to be adjusted is adjusted according to the torque adjustment ratio to obtain the execution torque; the execution torque is sent to the motor controller, and the motor controller is used to control the motor to work according to the execution torque, so as to automatically judge the skidding state through VCM, and quickly perform torque adjustment according to the skidding state judgment. VCM does not need to wait for the vehicle skidding judgment result and torque adjustment request of VDC. After VCM judges that the vehicle is skidding, it quickly performs skidding correction control and quickly requests the motor to execute, realizing fast anti-skid control.

[0102] In one embodiment, as Figure 3 shown, based on the first embodiment, the second embodiment of the anti-skid control method of the present invention is proposed. After the step S20, it further includes: when the current vehicle speed is less than the vehicle speed threshold, obtaining the execution torque of the previous cycle; adjusting the execution torque of the previous cycle to a preset torque, and using the preset torque as the execution torque.

[0103] In this embodiment, different torque increase algorithms are set according to the vehicle speed threshold, and an energy recovery value look-up table is added to the slip control algorithm. When the vehicle speed is low and the vehicle is in the slip control mode, the VCM can directly adjust the execution torque sent to the motor controller in the previous cycle to 0 Nm in the current cycle and send it to the motor controller via CAN. Since the vehicle speed is low at this time, directly adjusting it to 0 Nm can efficiently correct the slip while causing less impact to the driver.

[0104] In another provided embodiment, the torque control strategy includes a high-speed torque control strategy, and the step S30 includes:

[0105] In the step S301, when the current vehicle speed is greater than or equal to the vehicle speed threshold, a torque adjustment ratio is obtained by querying a torque adjustment ratio table according to the slip ratio and the energy recovery value, where the torque adjustment ratio table records the corresponding relationships among the slip ratio, the energy recovery value, and the torque adjustment ratio.

[0106] In this embodiment, at a higher vehicle speed, the current slip ratio and the energy recovery value are used as inputs to query a two-dimensional table. This table has been tested on a real vehicle on the road surface. Different torque adjustment ratios are obtained according to different slip ratios and different energy recovery values, and the torque is adjusted according to this ratio.

[0107] It should be noted that in order to obtain the energy recovery value, the current vehicle speed, the current braking torque, the motor operating state, and the battery operating state need to be obtained; the energy recovery value is determined according to the current vehicle speed, the current braking torque, the motor operating state, and the battery operating state.

[0108] In specific implementation, adjusting the torque to be adjusted according to the torque adjustment ratio to obtain the execution torque includes: obtaining the theoretical target torque according to the torque to be adjusted and the torque adjustment ratio; dividing the adjustment cycle into several time cycles according to the theoretical target torque; determining the theoretical target torques corresponding to the several time cycles; determining the torque increase rate and the execution torque for the next cycle according to the theoretical target torques corresponding to the several time cycles; and gradually increasing the torque to be adjusted in a gradient manner according to the torque increase rate and the execution torque until the adjusted torque reaches the theoretical target torque of the corresponding cycle, and then exiting the anti-slip control strategy.

[0109] Before the anti-slip control moment, the torque is -A Nm. The current anti-slip control is activated. By looking up the two-dimensional table, the rising ratio is f1. Then the calculated target torque rises to -A*f1 Nm. During the process of increasing the torque, it is divided into several adjustment cycles. When the target is to increase the torque to -A*f1 Nm, during the process of guiding the increase from -A Nm, it rises in the form of χ Nm / 0.01 s. Therefore, it rises in a gradient form. When the torque rises to -A1 Nm, the ratio value at the current moment is queried as f2. Then the target torque in the T2 stage rises to -A1*f2 Nm. Then, based on the target torque rising to -A1*f2 Nm, the rising torque in the next cycle is determined as -A2 Nm. When the actual torque rises from -A1 Nm to -A2 Nm, continue to look up the table until the actual torque value coincides with the target torque value obtained by looking up the table again. Then exit the anti-slip control strategy. Thus, under the dual coordinated control of the actual rising torque and the target torque, the adjustment trend of the torque is accurately controlled, and precision correction and control are carried out according to the adjustment trend of the torque to achieve precise control of the torque.

[0110] During the process of increasing the torque, dynamic adjustment is also carried out in real time, and the changes in the slip ratio and the energy recovery value are monitored in real time; when the torque adjustment ratio corresponding to the changed slip ratio and energy recovery value changes, the torque is increased according to the new torque adjustment ratio until the execution torque reaches the preset torque, that is, after several cycles of torque adjustment and increase, look up the table again according to the latest slip ratio and energy recovery value. Repeat this cycle until the vehicle state is adjusted to no longer slip, and then exit the anti-slip control, so as to avoid directly adjusting from a negative torque with a large absolute value to 0 Nm and prevent the vehicle from suffering a large impact.

[0111] In this embodiment, when the current vehicle speed of the vehicle is less than the vehicle speed threshold, the execution torque of the previous cycle is obtained according to the low-speed torque control strategy; the execution torque of the previous cycle is increased to the preset torque, and the preset torque is used as the execution torque. When the current vehicle speed is greater than or equal to the vehicle speed threshold, the torque adjustment ratio table is queried according to the current slip ratio and the current energy recovery value through the high-speed torque control strategy to obtain the current torque adjustment ratio, where the torque adjustment ratio table records the corresponding relationship between the slip ratio, the energy recovery value, and the corresponding torque adjustment ratio; the torque to be adjusted is dynamically adjusted according to the current torque adjustment ratio to obtain the execution torque, that is, two torque control strategies are used for control according to the vehicle speed, and the torque is adjusted according to the torque adjustment ratio, so as to achieve refined control of the torque, ensure a smooth transition of the torque, and improve the driving experience of the driver.

[0112] In one embodiment, after exiting the anti-skid control strategy, it further includes: switching the anti-skid control torque to the driver-intended torque; within the current cycle, obtaining the target torque according to the driver-intended torque and acquiring the current torque when exiting the anti-skid control strategy; obtaining the output torque according to the target torque, the filtering coefficient, and the current torque; sending the output torque to the motor controller, and controlling the motor to operate according to the output torque through the motor controller; within the next cycle, obtaining the next-cycle output torque according to the target torque, the filtering coefficient, and the output torque; sending the next-cycle output torque to the motor controller, and controlling the motor to operate according to the next-cycle output torque through the motor controller until the output torque reaches the target torque.

[0113] It should be noted that after exiting the anti-skid control, the torque recovery strategy. According to the current vehicle speed, battery state, etc., the VCM calculates the target torque, and this target torque changes according to a certain filtering coefficient (calibratable). This is to avoid the execution torque sent to the motor controller suddenly changing from the current torque to a negative torque with a relatively large absolute value, which may cause a large impact on the vehicle. The filtering coefficient can be adjusted according to the actual situation. In this embodiment, it is illustrated by taking 20% as an example. Since the priorities of the anti-skid control torque and the driver-intended torque are set, and the priority of the anti-skid control torque is greater than that of the driver-intended torque, when it is determined that the vehicle is in a skidding state, the driver-intended torque is blocked, and subsequent torque adjustments are made with the anti-skid control torque. However, after exiting the anti-skid control strategy, the input of the driver-intended torque is restored. In this case, it is necessary to adjust the torque after anti-skid control to the driver-intended torque. For example, if the torque after anti-skid control is -20 Nm and the driver-intended torque is -200 Nm, directly adjusting -20 Nm to -200 Nm will cause a large impact on the vehicle. Therefore, the above filtering coefficient is used to achieve a smooth adjustment of the torque.

[0114] The present invention further provides an anti-skid control device.

[0115] Referring to Figure 4 , Figure 4 is a schematic diagram of the functional modules of the first embodiment of the anti-skid control device of the present invention.

[0116] In the first embodiment of the anti-skid control device of the present invention, the anti-skid control device includes:

[0117] An acquisition module 10, configured to determine whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed difference during the vehicle coasting or braking process.

[0118] The acquisition module 10 is further configured to acquire the torque to be adjusted when the vehicle is in a skidding state.

[0119] The obtaining module 10 is further configured to, when the current vehicle speed is greater than or equal to the vehicle speed threshold, obtain a torque adjustment ratio according to the slip ratio and the energy recovery value.

[0120] The adjustment module 20 is configured to adjust the torque to be adjusted according to the torque adjustment ratio to obtain an execution torque.

[0121] The control module 30 is configured to send the execution torque to a motor controller, and control the motor to operate according to the execution torque through the motor controller.

[0122] In this embodiment, during vehicle coasting or braking, it is determined whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed differences; when the vehicle is in a skidding state, the torque to be adjusted is obtained; when the current vehicle speed is greater than or equal to the vehicle speed threshold, a torque adjustment ratio is obtained according to the slip ratio and the energy recovery value; the torque to be adjusted is adjusted according to the torque adjustment ratio to obtain an execution torque; the execution torque is sent to the motor controller, and the motor is controlled to operate according to the execution torque through the motor controller, so as to automatically judge the skidding state by VCM, and quickly adjust the torque according to the skidding state judgment. VCM does not need to wait for the vehicle skidding judgment result and torque adjustment request of VDC. After VCM judges that the vehicle is skidding, it quickly performs skidding correction control and quickly requests the motor to execute, realizing fast anti-skid control.

[0123] Optionally, the obtaining module 10 is further configured to, when the current vehicle speed is greater than or equal to the vehicle speed threshold, obtain the front wheel speed and the rear wheel speed of the vehicle;

[0124] Obtain a slip ratio according to the front wheel speed and the rear wheel speed;

[0125] When the slip ratio is greater than or equal to the slip ratio threshold, it is determined that the vehicle is in a skidding state.

[0126] Optionally, when the vehicle is a front-wheel drive vehicle, the obtaining module 10 is further configured to obtain a first difference between the rear wheel speed and the front wheel speed of the vehicle;

[0127] Obtain a slip ratio according to the first difference and the rear wheel speed;

[0128] When the vehicle is a rear-wheel drive vehicle, obtain a second difference between the front wheel speed and the rear wheel speed;

[0129] Obtain a slip ratio according to the second difference and the front wheel speed.

[0130] Optionally, the obtaining module 10 is further configured to, when the current vehicle speed is less than the vehicle speed threshold, obtain the front wheel speed and the rear wheel speed of the vehicle;

[0131] Obtain the front and rear wheel speed difference based on the front wheel speed and the rear wheel speed;

[0132] When the front and rear wheel speed difference is greater than or equal to the wheel speed threshold, determine that the vehicle is in a skidding state.

[0133] Optionally, the obtaining module 10 is further configured to, when the vehicle is a front-wheel drive vehicle, subtract the front wheel speed from the rear wheel speed to obtain the front and rear wheel speed difference;

[0134] When the vehicle is a rear-wheel drive vehicle, subtract the rear wheel speed from the front wheel speed to obtain the front and rear wheel speed difference.

[0135] Optionally, the obtaining module 10 is further configured to obtain a gear signal;

[0136] When the gear signal is a forward gear signal, no acceleration pedal depression signal is detected, the slip ratio is greater than or equal to the slip ratio threshold, or the front and rear wheel speed difference is greater than or equal to the wheel speed threshold, determine that the vehicle is in a skidding state.

[0137] Optionally, the adjustment module 20 is further configured to set the priority of the anti-skid control torque and the driver intention torque, so that the priority of the anti-skid control torque is greater than the priority of the driver intention torque.

[0138] Optionally, the obtaining module 10 is further configured to obtain the anti-skid control torque and the driver intention torque when the vehicle is in a skidding state;

[0139] Mask the driver intention torque according to the priority of the anti-skid control torque and the driver intention torque, and use the anti-skid control torque as the torque to be adjusted.

[0140] Optionally, the obtaining module 10 is further configured to obtain the execution torque of the previous cycle when the current vehicle speed is less than the vehicle speed threshold;

[0141] Adjust the execution torque of the previous cycle to a preset torque, and use the preset torque as the execution torque.

[0142] Optionally, the obtaining module 10 is further configured to query a torque adjustment ratio table according to the slip ratio and the energy recovery value when the current vehicle speed is greater than or equal to the vehicle speed threshold, to obtain a torque adjustment ratio, where the torque adjustment ratio table records the corresponding relationship between the slip ratio, the energy recovery value, and the torque adjustment ratio.

[0143] Optionally, the obtaining module 10 is further configured to obtain the current vehicle speed, the current braking torque, the motor operating state, and the battery operating state;

[0144] Determine the energy recovery value according to the current vehicle speed, current braking torque, motor operating state, and battery operating state.

[0145] Optionally, the adjustment module 20 is further configured to obtain a theoretical target torque according to the torque to be adjusted and the torque adjustment ratio;

[0146] Divide the adjustment period into several time periods according to the theoretical target torque;

[0147] Determine the theoretical target torques corresponding to the several time periods;

[0148] Determine the torque rising rate and the execution torque for the next period according to the theoretical target torques corresponding to the several time periods;

[0149] Gradually increase the torque to be adjusted according to the torque rising rate and the execution torque until the adjusted torque reaches the theoretical target torque for the corresponding period, and then exit the anti-skid control strategy.

[0150] Optionally, the adjustment module 20 is further configured to monitor the changes in the slip ratio and the energy recovery value in real time;

[0151] When the torque adjustment ratio corresponding to the changed slip ratio and energy recovery value changes, determine the theoretical target torques corresponding to the several time periods according to the new torque adjustment ratio.

[0152] Optionally, the adjustment module 20 is further configured to switch the anti-skid control torque to the driver's intended torque;

[0153] In the current period, obtain the target torque according to the driver's intended torque and the current torque when exiting the anti-skid control strategy;

[0154] Obtain the output torque according to the target torque, the filtering coefficient, and the current torque;

[0155] Send the output torque to the motor controller, and control the motor to operate according to the output torque through the motor controller;

[0156] In the next period, obtain the output torque for the next period according to the target torque, the filtering coefficient, and the output torque;

[0157] Send the output torque for the next period to the motor controller, and control the motor to operate according to the output torque for the next period through the motor controller until the output torque reaches the target torque.

[0158] In addition, to achieve the above object, the present invention further provides an anti-slip control device, which includes: a memory, a processor, and an anti-slip control program stored on the memory and executable on the processor, and the anti-slip control program is configured to implement the anti-slip control method as described above.

[0159] In addition, an embodiment of the present invention further provides a storage medium, on which an anti-slip control program is stored, and when the anti-slip control program is executed by a processor, it implements the anti-slip control method as described above.

[0160] Since this storage medium adopts all the technical solutions of the above-mentioned all embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, and will not be elaborated here one by one.

[0161] It should be noted that in this article, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or system. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or system including that element.

[0162] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages and disadvantages of the embodiments.

[0163] Through the description of the above embodiments, those skilled in the art can clearly understand that the above embodiment methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a computer-readable storage medium as described above (such as ROM / RAM, magnetic disk, optical disc), and includes several instructions for causing an intelligent terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0164] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. An anti-slip control method, characterized in that, Applied to a vehicle control unit, the anti-skid control method includes: During vehicle coasting or braking, determining whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed difference; When the vehicle is in a skidding state, obtaining an adjustment torque to be adjusted, where the adjustment torque to be adjusted is the execution torque of the previous cycle; When the current vehicle speed is greater than or equal to the vehicle speed threshold, obtaining a torque adjustment ratio according to the slip ratio and the energy recovery value; Adjusting the adjustment torque to be adjusted according to the torque adjustment ratio to obtain an execution torque; Sending the execution torque to a motor control unit, and controlling the motor to operate according to the execution torque through the motor control unit; The step of, when the current vehicle speed is greater than or equal to the vehicle speed threshold, obtaining a torque adjustment ratio according to the slip ratio and the energy recovery value includes: When the current vehicle speed is greater than or equal to the vehicle speed threshold, querying a torque adjustment ratio table according to the slip ratio and the energy recovery value to obtain a torque adjustment ratio, where the torque adjustment ratio table records the corresponding relationship between the slip ratio, the energy recovery value, and the torque adjustment ratio; The step of determining whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed difference includes: Obtaining a gear signal; When the gear signal is a forward gear signal and no acceleration pedal depression signal is detected, determining whether the slip ratio is greater than or equal to a slip ratio threshold or whether the front and rear wheel speed difference is greater than or equal to a wheel speed threshold; When the slip ratio is greater than or equal to the slip ratio threshold or the front and rear wheel speed difference is greater than or equal to the wheel speed threshold, determining that the vehicle is in a skidding state.

2. The anti-slip control method according to claim 1, characterized in that, Determining whether the vehicle is in a skidding state according to the slip ratio includes: When the current vehicle speed is greater than or equal to the vehicle speed threshold, obtaining the front wheel speed and the rear wheel speed of the vehicle; When the vehicle is a front-wheel drive vehicle, obtaining a first difference between the rear wheel speed and the front wheel speed; Obtaining a slip ratio according to the first difference and the rear wheel speed; When the vehicle is a rear-wheel drive vehicle, obtaining a second difference between the front wheel speed and the rear wheel speed; Obtaining a slip ratio according to the second difference and the front wheel speed; When the slip ratio is greater than or equal to the slip ratio threshold, determining that the vehicle is in a skidding state.

3. The anti-slip control method according to claim 1, wherein Determining whether the vehicle is in a skidding state according to the front and rear wheel speed difference includes: When the current vehicle speed is less than the vehicle speed threshold, obtaining the front wheel speed and the rear wheel speed of the vehicle; When the vehicle is a front-wheel drive vehicle, subtracting the front wheel speed from the rear wheel speed to obtain a front and rear wheel speed difference; When the vehicle is a rear-wheel drive vehicle, subtracting the rear wheel speed from the front wheel speed to obtain a front and rear wheel speed difference; When the front and rear wheel speed difference is greater than or equal to the wheel speed threshold, determining that the vehicle is in a skidding state.

4. The anti-slip control method according to any one of claims 1 to 3, characterized in that, Before the step of, during vehicle coasting or braking, determining whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed difference, further includes: Setting the priorities of the anti-skid control torque and the driver intention torque, so that the priority of the anti-skid control torque is greater than the priority of the driver intention torque; The step of, when the vehicle is in a skidding state, obtaining an adjustment torque to be adjusted includes: When the vehicle is in a skidding state, obtaining the anti-skid control torque and the driver intention torque; According to the priority of the anti-slip control torque and the driver's intended torque, shield the driver's intended torque and use the anti-slip control torque as the torque to be adjusted.

5. The anti-slip control method according to any one of claims 1 to 3, characterized in that After obtaining the torque to be adjusted when the vehicle is in a skidding state, it further includes: When the current vehicle speed is less than the vehicle speed threshold, obtain the execution torque of the previous cycle; Adjust the execution torque of the previous cycle to a preset torque and use the preset torque as the execution torque.

6. The anti-slip control method according to any one of claims 1 to 3, characterized in that, Before obtaining the torque adjustment ratio according to the slip ratio and the energy recovery value when the current vehicle speed is greater than or equal to the vehicle speed threshold, it further includes: Obtain the current vehicle speed, the current braking torque, the motor operating state, and the battery operating state; Determine the energy recovery value according to the current vehicle speed, the current braking torque, the motor operating state, and the battery operating state.

7. The anti-slip control method according to any one of claims 1 to 3, characterized in that, Adjusting the torque to be adjusted according to the torque adjustment ratio to obtain the execution torque includes: Obtain the theoretical target torque according to the torque to be adjusted and the torque adjustment ratio; Divide the adjustment cycle into several time periods according to the theoretical target torque; Determine the theoretical target torque corresponding to the several time periods; Determine the torque rising rate and the execution torque of the next cycle according to the theoretical target torque corresponding to the several time periods; According to the torque rising rate and the execution torque, increase the torque to be adjusted in a gradient manner until the adjusted torque reaches the theoretical target torque of the corresponding cycle.

8. The anti-slip control method according to claim 7, characterized in that, Determining the theoretical target torque corresponding to the several time periods includes: Real-time monitor the changes in the slip ratio and the energy recovery value; When the torque adjustment ratio corresponding to the changed slip ratio and energy recovery value changes, determine the theoretical target torque corresponding to the several time periods according to the new torque adjustment ratio.

9. The anti-slip control method according to claim 7, characterized in that, After the adjusted torque reaches the theoretical target torque of the corresponding cycle, it further includes: Exit the anti-slip control strategy and switch the anti-slip control torque to the driver's intended torque; In the current cycle, obtain the target torque according to the driver's intended torque and the current torque when exiting the anti-slip control strategy; Obtain the output torque according to the target torque, the filtering coefficient, and the current torque; Send the output torque to the motor controller, and control the motor to work according to the output torque through the motor controller; In the next cycle, obtain the output torque of the next cycle according to the target torque, the filtering coefficient, and the output torque; Send the output torque of the next cycle to the motor controller, and control the motor to work according to the output torque of the next cycle through the motor controller until the output torque reaches the target torque.

10. An anti-slip control device, characterized in that, The anti-slip control device includes: An acquisition module, configured to determine whether the vehicle is in a skidding state according to the slip ratio or the front and rear wheel speed difference during the vehicle coasting or braking process; The acquisition module is further configured to obtain the torque to be adjusted when the vehicle is in a skidding state, and the torque to be adjusted is the execution torque of the previous cycle; The acquisition module is further configured to obtain the torque adjustment ratio according to the slip ratio and the energy recovery value when the current vehicle speed is greater than or equal to the vehicle speed threshold; An adjustment module, configured to adjust the torque to be adjusted according to the torque adjustment ratio to obtain an execution torque; A control module, configured to send the execution torque to a motor controller, and control the motor to operate according to the execution torque through the motor controller; The acquisition module is further configured to, when the current vehicle speed is greater than or equal to a vehicle speed threshold, query a torque adjustment ratio table according to the slip ratio and the energy recovery value to obtain a torque adjustment ratio, wherein the torque adjustment ratio table records the corresponding relationship between the slip ratio, the energy recovery value, and the torque adjustment ratio; The acquisition module is further configured to acquire a gear signal; when the gear signal is a forward gear signal and no acceleration pedal depression signal is detected, determine whether the slip ratio is greater than or equal to a slip ratio threshold or whether the wheel speed difference between the front and rear wheels is greater than or equal to a wheel speed threshold; when the slip ratio is greater than or equal to the slip ratio threshold or the wheel speed difference between the front and rear wheels is greater than or equal to the wheel speed threshold, determine that the vehicle is in a skidding state.

11. An anti-slip control device, characterized in that, The anti-skid control device includes: a memory, a processor, and an anti-skid control program stored on the memory and executable on the processor, the anti-skid control program being configured to implement the anti-skid control method according to any one of claims 1 to 9.

12. A storage medium, characterized in that, An anti-skid control program is stored on the storage medium, and when the anti-skid control program is executed by a processor, the anti-skid control method according to any one of claims 1 to 9 is implemented.

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