A wheel anti-lock control method, device, equipment and storage medium

Abstract

The present application provides a wheel anti-lock control method, device, equipment and storage medium, firstly obtaining the motor target torque and motor speed lower limit calculated by the vehicle controller, and then sending them to the motor controller; then reading the motor speed of the motor controller itself, recording it as the current motor speed; then comparing the current motor speed with the motor speed lower limit received by the motor controller, and when the current motor speed is greater than the motor speed lower limit, using the motor target torque to perform wheel anti-lock control on the target vehicle; conversely, using the motor speed lower limit received by the motor controller to perform wheel anti-lock control on the target vehicle. The present application can effectively solve the problem that the control parameter transmission path in the traditional anti-lock control is too long when there is large electric feedback, which makes it easy for the wheel to lock, and the problem that using estimated parameters to control the vehicle brings about large calibration work and large errors, and also brings more initiative to the vehicle longitudinal stability control for the OEM.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a wheel anti-lock braking control method, device, equipment and storage medium. Background Art

[0002] The wheels of a vehicle are prone to lock when a large braking force is applied, especially when driving on slippery or icy roads. When the wheels are locked, the vehicle cannot turn and is prone to sideways skidding or overturning, endangering the safety of the vehicle, the driver, and pedestrians.

[0003] For electric vehicles, most of them still follow the chassis control system of fuel vehicles in terms of wheel anti-lock control. The chassis control system needs to calculate the wheel slip rate and coordinate the control of the motor and hydraulic braking force through the vehicle controller or chassis controller to achieve wheel anti-lock. However, this method has two significant problems when large electric feedback (such as more than 0.2g) is involved in braking:

[0004] (1) On some special roads or scenarios, such as icy and snowy roads with low adhesion coefficients, or when the wheels are in the air for a long time when going over speed bumps, the control parameters need to be transmitted between the chassis controller-vehicle controller-motor controller-motor. The long transmission path leads to slow torque response. When the chassis controller detects that the wheel is tending to lock, the motor torque increase demand sent by the chassis controller cannot be transmitted to the wheel end in time, which makes the wheel lock easily. In order to obtain a better anti-lock control effect, a large amount of multi-party coordination and calibration work is required.

[0005] (2) The core parameter in the slip rate calculation is the reference speed, which is the speed estimated by the wheel speed sensor. The original wheel speed signal actually outputs a signal when the wheel rotates about 7.5°. Taking the vehicle speed of 40km / h as an example, it takes about 190ms. However, when the vehicle brakes at a deceleration of 0.2g, the wheel will lock in less than 100ms. Therefore, the accuracy of the estimated speed has a great impact on the anti-lock control effect. The speed estimation model itself needs a lot of calibration work. In addition, using the estimated signal to actually control the vehicle will bring about a large error. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art, the present application provides a wheel anti-lock braking control method, device, equipment and storage medium to solve the above-mentioned technical problems.

[0007] The present application provides a wheel anti-lock braking control method, comprising the following steps:

[0008] Obtain the motor target torque and motor speed lower limit calculated by the vehicle controller;

[0009] Sending the motor target torque and the motor speed lower limit to the motor controller, and reading the motor speed of the motor controller itself, which is recorded as the current motor speed;

[0010] Comparing the current motor speed with the motor speed lower limit;

[0011] When the current motor speed is greater than the motor speed lower limit, the motor target torque is used to perform wheel anti-lock control on the target vehicle; or, when the current motor speed is less than or equal to the motor speed lower limit, the motor speed lower limit is used to perform wheel anti-lock control on the target vehicle; wherein the target vehicle includes a vehicle determined in advance or in real time.

[0012] In one embodiment of the present application, the process of the vehicle controller calculating the lower limit of the motor speed includes:

[0013] Calculate the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , and calculate the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 ;

[0014] Determining whether the motor participates in regenerative braking of the target vehicle;

[0015] If the motor does not participate in the regenerative braking of the target vehicle, stopping the wheel anti-lock control of the target vehicle;

[0016] If the motor participates in the regenerative braking of the target vehicle, the motor speed corresponding to the non-locked wheel in the current cycle is obtained, and the motor speed angular acceleration β0 and the angular acceleration change gradient γ0 corresponding to the non-locked wheel in the current cycle are calculated;

[0017] According to the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 , and the angular acceleration change gradient γ0, calculate the motor angular acceleration change gradient γ in the next cycle, and we have:

[0018]

[0019] The motor speed lower limit w for the next cycle is calculated according to the motor angular acceleration change gradient γ for the next cycle.

[0020] In one embodiment of the present application, the process of calculating the motor speed lower limit value w of the next cycle according to the motor angular acceleration change gradient γ of the next cycle includes:

[0021] Obtain the average motor speed w0 corresponding to the current non-locked wheel and the execution cycle duration T of the vehicle controller;

[0022] According to the motor speed angular acceleration β0 corresponding to the non-locked wheel in the current cycle, the motor angular acceleration change gradient γ in the next cycle, the average motor speed w0 corresponding to the non-locked wheel in the current cycle, and the execution cycle duration T of the vehicle controller, the motor speed lower limit w in the next cycle is calculated, as follows:

[0023] w=w0+(β0+γ)*dT.

[0024] In one embodiment of the present application, before obtaining the average motor speed w0 corresponding to the current non-locked wheel, the method further includes:

[0025] Get the vehicle wheel speed corresponding to the current non-locked wheel;

[0026] The vehicle wheel speed corresponding to the current non-locked wheel is converted into the motor speed corresponding to the current non-locked wheel, and the average motor speed corresponding to the current non-locked wheel is calculated.

[0027] In one embodiment of the present application, after performing wheel anti-lock control on the target vehicle using the motor target torque, the method further includes:

[0028] Obtaining a preset speed value, and summing the preset speed value and the motor speed lower limit value to obtain a speed hysteresis value;

[0029] The current motor speed is compared with the speed hysteresis value, and when the current motor speed is greater than the speed hysteresis value, the wheel anti-lock control of the target vehicle is stopped; or when the current motor speed is less than or equal to the speed hysteresis value, the wheel anti-lock control of the target vehicle is maintained.

[0030] In one embodiment of the present application, the cycle length of the vehicle controller calculating the motor target torque and the motor speed lower limit is 10 milliseconds;

[0031] The cycle duration of reading the motor speed of the motor controller itself is less than or equal to 1 millisecond.

[0032] In one embodiment of the present application, the target vehicle includes: a new energy vehicle.

[0033] The present application also provides a wheel anti-lock control device, the device comprising:

[0034] The data acquisition module is used to obtain the motor target torque and the motor speed lower limit calculated by the vehicle controller;

[0035] A motor speed module, used for sending the motor target torque and the motor speed lower limit to the motor controller, and reading the motor speed of the motor controller itself, which is recorded as the current motor speed;

[0036] A comparison module, used for comparing the current motor speed with the motor speed lower limit;

[0037] An anti-lock control module is used to perform wheel anti-lock control on a target vehicle using the motor target torque when the current motor speed is greater than the motor speed lower limit; or to perform wheel anti-lock control on the target vehicle using the motor speed lower limit when the current motor speed is less than or equal to the motor speed lower limit; wherein the target vehicle includes a vehicle determined in advance or in real time.

[0038] In one embodiment of the present application, the process of calculating the lower limit of the motor speed by the vehicle controller in the data acquisition module includes:

[0039] Calculate the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , and calculate the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 ;

[0040] Determining whether the motor participates in regenerative braking of the target vehicle;

[0041] If the motor does not participate in the regenerative braking of the target vehicle, stopping the wheel anti-lock control of the target vehicle;

[0042] If the motor participates in the regenerative braking of the target vehicle, the motor speed corresponding to the non-locked wheel in the current cycle is obtained, and the motor speed angular acceleration β0 and the angular acceleration change gradient γ0 corresponding to the non-locked wheel in the current cycle are calculated;

[0043] According to the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 , and the angular acceleration change gradient γ0, calculate the motor angular acceleration change gradient γ in the next cycle, and we have:

[0044]

[0045] The motor speed lower limit w for the next cycle is calculated according to the motor angular acceleration change gradient γ for the next cycle.

[0046] In one embodiment of the present application, the process of calculating the motor speed lower limit value w of the next cycle according to the motor angular acceleration change gradient γ of the next cycle includes:

[0047] Obtain the average motor speed w0 corresponding to the current non-locked wheel and the execution cycle duration T of the vehicle controller;

[0048] According to the motor speed angular acceleration β0 corresponding to the non-locked wheel in the current cycle, the motor angular acceleration change gradient γ in the next cycle, the average motor speed w0 corresponding to the non-locked wheel in the current cycle, and the execution cycle duration T of the vehicle controller, the motor speed lower limit w in the next cycle is calculated, as follows:

[0049] w=w0+(β0+γ)*dT.

[0050] The present application also provides a wheel anti-lock control device, the device comprising:

[0051] one or more processors;

[0052] A storage device is used to store one or more programs. When the one or more programs are executed by the one or more processors, the device implements the wheel anti-lock braking control method as described in any one of the above.

[0053] The present application also provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor of a computer, the computer is enabled to execute the wheel anti-lock braking control method as described in any one of the above.

[0054] As described above, the present application provides a wheel anti-lock braking control method, device, equipment and storage medium, which have the following beneficial effects:

[0055] The present application first obtains the motor target torque and the motor speed lower limit calculated by the vehicle controller; then sends the motor target torque and the motor speed lower limit to the motor controller, and reads the motor speed of the motor controller itself, which is recorded as the current motor speed; then compares the current motor speed with the motor speed lower limit received by the motor controller, and when the current motor speed is greater than the motor speed lower limit, uses the motor target torque to perform wheel anti-lock control on the target vehicle; or, when the current motor speed is less than or equal to the motor speed lower limit, uses the motor speed lower limit received by the motor controller to perform wheel anti-lock control on the target vehicle. Wherein, the target vehicle includes a vehicle determined in advance or in real time. It can be seen that the present application proposes a wheel anti-lock control scheme that uses the motor speed as a control signal and shortens the control path, which can effectively solve the problem that the control parameter transmission path in the traditional anti-lock control is too long when there is large electric feedback, resulting in easy occurrence of wheel locking, and the use of estimated parameters to control the vehicle brings about large calibration work and large errors. At the same time, it also brings more initiative to the vehicle longitudinal stability control for the OEM.

[0056] In addition, the present application can limit the anti-lock control of the wheel to the shorter transmission chain of motor controller MCU (Motor Control Unit, motor controller, referred to as MCU) - motor - wheel, and the signal transmission loop is limited to motor controller MCU - motor (resolver) - motor controller MCU, and the program execution cycle of the motor controller MCU is less than or equal to 1ms. The anti-lock control loop theoretically takes only about 1 millisecond, which is much lower than the more than 30 milliseconds of traditional control. The motor speed change can be monitored and controlled in real time, which can meet the high dynamic response requirements of anti-lock control. At the same time, the present application uses the motor resolver signal to detect whether the vehicle is locked. The worst industry accuracy of this signal is generally less than 0.5° of the motor rotation. It is still less than 0.06° when converted to the wheel with a speed ratio of 9, which is much larger than the 7.5° angle of the traditional wheel speed signal. The detection of wheel speed changes is more accurate, and there is no need for a model to estimate and calibrate the wheel speed.

[0057] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0059] Figure 1 A schematic diagram of an exemplary system architecture for applying the technical solutions in one or more embodiments of the present application;

[0060] Figure 2 A schematic diagram of a flow chart of a wheel anti-lock braking control method provided in an embodiment of the present application;

[0061] Figure 3 A schematic diagram of a flow chart of calculating the lower limit of the motor speed within a vehicle controller provided in an embodiment of the present application;

[0062] Figure 4 A schematic diagram of the control flow inside a motor controller provided in an embodiment of the present application;

[0063] Figure 5 A schematic diagram of a signal flow for wheel anti-lock braking control provided by an embodiment of the present application;

[0064] Figure 6 A signal flow diagram of an existing wheel anti-lock braking control system provided by an embodiment of the present application;

[0065] Figure 7 A schematic diagram of the hardware structure of a wheel anti-lock braking control system provided in an embodiment of the present application;

[0066] Figure 8 The figure is a schematic diagram of the hardware structure of a wheel anti-lock braking control device suitable for implementing one or more embodiments of the present application. DETAILED DESCRIPTION

[0067] The following will describe the implementation methods of the present application with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be understood that the preferred embodiments are only for illustrating the present application, not for limiting the scope of protection of the present application.

[0068] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application, and thus the drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated.

[0069] The term "and / or" in this application describes the relationship between associated objects, indicating that three relationships may exist. For example, A and / or B may represent the following three situations: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0070] The term "plurality" in this application refers to two or more.

[0071] In the description of this application, words such as "first" and "second" are only used for the purpose of distinguishing the description and cannot be understood as indicating or implying relative importance or order.

[0072] In addition, in the embodiments of the present application, the word "exemplary" is used to indicate an example, illustration or description. Any embodiment or implementation described as "exemplary" in the present application should not be interpreted as being more preferred or more advantageous than other embodiments or implementations. Specifically, the use of the word "exemplary" is intended to present concepts in a concrete way.

[0073] In the following description, a large number of details are discussed to provide a more thorough explanation of the embodiments of the present application. However, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present application difficult to understand.

[0074] Figure 1 A schematic diagram of an exemplary system architecture to which the technical solution in one or more embodiments of the present application can be applied is shown. Figure 1 As shown, the system architecture 100 may include a terminal device 110, a network 120, and a server 130. The terminal device 110 may include various electronic devices such as a smart phone, a tablet computer, a laptop computer, and a desktop computer. The server 130 may be an independent physical server, or a server cluster or a distributed system composed of multiple physical servers, or a cloud server providing cloud computing services. The network 120 may be a communication medium of various connection types that can provide a communication link between the terminal device 110 and the server 130, such as a wired communication link or a wireless communication link.

[0075] According to the implementation requirements, the system architecture in the embodiment of the present application can have any number of terminal devices, networks and servers. For example, the server 130 can be a server group composed of multiple server devices. In addition, the technical solution provided in the embodiment of the present application can be applied to the terminal device 110, can also be applied to the server 130, or can be implemented by the terminal device 110 and the server 130 together, and the present application does not make any special restrictions on this.

[0076] In one embodiment of the present application, the terminal device 110 or the server 130 of the present application can first obtain the motor target torque and the motor speed lower limit calculated by the vehicle controller; then send the motor target torque and the motor speed lower limit to the motor controller, and read the motor speed of the motor controller itself, which is recorded as the current motor speed; then compare the current motor speed with the motor speed lower limit received by the motor controller, and when the current motor speed is greater than the motor speed lower limit, use the motor target torque to perform wheel anti-lock control on the target vehicle; or, when the current motor speed is less than or equal to the motor speed lower limit, use the motor speed lower limit received by the motor controller to perform wheel anti-lock control on the target vehicle. Using the terminal device 110 or the server 130 to execute the wheel anti-lock control method can effectively solve the problem that the control parameter transmission path in the traditional anti-lock control is too long when the electric feedback is large, which makes the wheel lock easy to occur, and the problem that the use of estimated parameters to control the vehicle brings about a large calibration work and a large error, and at the same time, it also brings more initiative to the vehicle longitudinal stability control for the OEM. In addition, the wheel anti-lock control can be limited to the shorter transmission chain of motor controller MCU-motor-wheel, and the signal transmission loop can be limited to the transmission chain of motor controller MCU-motor (resolver)-motor controller MCU. Thus, the speed change of the motor can be monitored and controlled in real time, meeting the high dynamic response requirements of anti-lock control.

[0077] The above section introduces the contents of an exemplary system architecture that applies the technical solution of the present application. Next, the wheel anti-lock braking control method of the present application will be introduced.

[0078] Figure 2 FIG. 2 shows a schematic flow chart of a wheel anti-lock braking control method provided by an embodiment of the present application. Specifically, in an exemplary embodiment, Figure 2 As shown, this embodiment provides a wheel anti-lock braking control method, the method comprising the following steps:

[0079] S210, obtaining the motor target torque and the motor speed lower limit calculated by the vehicle controller;

[0080] S220, sending the motor target torque and the motor speed lower limit to a motor controller, and reading the motor speed of the motor controller itself, which is recorded as the current motor speed;

[0081] S230, comparing the current motor speed with the motor speed lower limit;

[0082] S240, when the current motor speed is greater than the motor speed lower limit, the motor target torque is used to perform wheel anti-lock control on the target vehicle; or, when the current motor speed is less than or equal to the motor speed lower limit, the motor speed lower limit is used to perform wheel anti-lock control on the target vehicle; wherein the target vehicle includes a vehicle determined in advance or in real time. As an example, the target vehicle in this embodiment may be a new energy vehicle, such as an electric vehicle.

[0083] It can be seen that this embodiment can effectively solve the problem that the control parameter transmission path in the traditional anti-lock control is too long when the electric feedback is large, which leads to easy wheel locking, and the use of estimated parameters to control the vehicle brings about large calibration work and large errors. At the same time, it also brings more initiative to the vehicle longitudinal stability control for the main engine manufacturer. In addition, this embodiment can limit the anti-lock control of the wheel to the shorter transmission chain of the motor controller MCU-motor-wheel, and the signal transmission loop is limited to the transmission chain of the motor controller MCU-motor (resolver)-motor controller MCU; thus, the speed change of the motor can be monitored and controlled in real time, meeting the high dynamic response requirements of the anti-lock control.

[0084] In an exemplary embodiment, the process of calculating the lower limit of the motor speed by the vehicle control unit (VCU) includes:

[0085] Calculate the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , and calculate the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 ;

[0086] Determining whether the motor participates in regenerative braking of the target vehicle;

[0087] If the motor does not participate in the regenerative braking of the target vehicle, stopping the wheel anti-lock control of the target vehicle;

[0088] If the motor participates in the regenerative braking of the target vehicle, the motor speed corresponding to the non-locked wheel in the current cycle is obtained, and the motor speed angular acceleration β0 and the angular acceleration change gradient γ0 corresponding to the non-locked wheel in the current cycle are calculated;

[0089] According to the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 , and the angular acceleration change gradient γ0, calculate the motor angular acceleration change gradient γ in the next cycle, and we have:

[0090]

[0091] The motor speed lower limit w for the next cycle is calculated according to the motor angular acceleration change gradient γ for the next cycle.

[0092] According to the above records, specifically, the process of calculating the motor speed lower limit w of the next cycle according to the motor angular acceleration change gradient γ of the next cycle includes:

[0093] Obtain the average motor speed w0 corresponding to the current non-locked wheel and the execution cycle duration T of the vehicle controller;

[0094] According to the motor speed angular acceleration β0 corresponding to the non-locked wheel in the current cycle, the motor angular acceleration change gradient γ in the next cycle, the average motor speed w0 corresponding to the non-locked wheel in the current cycle, and the execution cycle duration T of the vehicle controller, the motor speed lower limit w in the next cycle is calculated, as follows:

[0095] w=w0+(β0+γ)*dT.

[0096] According to the above records, in an exemplary embodiment, before obtaining the average motor speed w0 corresponding to the current non-locked wheel, the method further includes: obtaining the vehicle wheel speed corresponding to the current non-locked wheel; converting the vehicle wheel speed corresponding to the current non-locked wheel into the motor speed corresponding to the current non-locked wheel, and calculating the average motor speed corresponding to the current non-locked wheel. It can be seen that in this embodiment, for the wheel-side motor or wheel hub motor, this embodiment converts the speed of the wheel-side motor or wheel hub motor that is not slipping into the speed of the drive shaft on the longitudinal axis of the vehicle according to the vehicle kinematics and dynamics theory and the steering wheel angle, and then uses it as the non-locked motor speed.

[0097] In an exemplary embodiment, after the target vehicle is subjected to wheel anti-lock control using the motor target torque, the method further includes: obtaining a preset speed value, and summing the preset speed value and the motor speed lower limit value to obtain a speed hysteresis value; comparing the current motor speed with the speed hysteresis value, and when the current motor speed is greater than the speed hysteresis value, stopping the wheel anti-lock control of the target vehicle; or, when the current motor speed is less than or equal to the speed hysteresis value, maintaining the wheel anti-lock control of the target vehicle. It can be seen that this embodiment forms hysteresis by setting a speed hysteresis value, thereby preventing the motor controller MCU from frequently jumping back and forth between the activation and deactivation of the anti-lock function.

[0098] According to the above records, in an exemplary embodiment, the cycle length of the vehicle controller calculating the motor target torque and the motor speed lower limit is 10 milliseconds; the cycle length of reading the motor speed of the motor controller itself is less than or equal to 1 millisecond.

[0099] In another exemplary embodiment of the present application, the embodiment also provides a wheel anti-lock control method, which includes two stages, namely: a first stage in which the vehicle controller VCU calculates the motor target torque and the lower limit value of the speed, and sends the calculated motor target torque and the lower limit value of the speed to the motor controller MCU; and a second stage after the motor controller receives the motor target torque and the lower limit value of the speed.

[0100] Among them, in the first stage, the vehicle controller VCU calculates and sends the motor target torque and speed lower limit to the motor controller MCU. The execution time of a single cycle of the vehicle controller VCU is 10ms. The process of the vehicle controller VCU calculating the motor speed lower limit is as follows Figure 3 Specifically, for a specific vehicle, the motor torque T q The relationship with angular acceleration β is: T q =J*β, taking the derivative of both sides of the equation, we can get dT q / dβ=J, J is the moment of inertia of the motor system, which is a constant; that is, the change in the motor target torque is proportional to the change in the motor angular acceleration. And in the signal at the vehicle controller VCU end, the torque change of the vehicle controller VCU is one cycle faster than the change in the motor speed. The target torque currently sent to the motor by the vehicle controller VCU needs to be read in the next cycle to be the motor speed generated by the torque of the current cycle. Based on this, according to the target torque change dT sent to the motor by the vehicle controller VCU in the previous cycle q-1 , and the ratio of the motor angular acceleration change γ0 (i.e. dβ) detected by the vehicle controller VCU in the current cycle Should be equal to the target torque change value dT sent to the motor by the vehicle controller VCU in the current cycle q0 , and the ratio of the motor angular acceleration change value γ in the next cycle, that is:

[0101]

[0102] but:

[0103]

[0104] Then the angular velocity of the motor in the next cycle is:

[0105] w=w0+β*dT=w0+(β0+γ)*dT③;

[0106] According to the above theory, the vehicle controller VCU can predict the lower limit value of the motor speed in the next program cycle of the vehicle controller VCU, and use this value as the lower limit value of the motor speed in the next program cycle of the vehicle controller VCU.

[0107] It can be seen from this that the logic of calculating the lower limit of the motor speed inside the vehicle controller VCU in this embodiment is:

[0108] 1. Calculate the target torque change dT of the VCU generator in the current cycle q0 and the target torque change gradient dT of the previous cycle q-1 ;

[0109] 2. Determine whether the motor is involved in feedback and braking. When the motor does not participate in the vehicle's feedback braking, the vehicle braking is pure hydraulic braking. At this time, the control is only completed inside the chassis controller. The control parameter transmission path is short, which is the chassis controller-brake hydraulic pipeline-wheel. The risk of wheel locking is relatively small. At this time, the vehicle controller VCU does not perform anti-lock control. When the motor participates in the vehicle's feedback braking and the motor speed is not negative (negative means that the motor drives the vehicle in the opposite direction of the gear), the anti-lock program controlled by the vehicle controller VCU is entered.

[0110] 3. After entering the anti-lock program controlled by the vehicle controller VCU, obtain the motor speed or vehicle wheel speed corresponding to the current non-locked wheel, convert it to the motor speed, and take the average value w0. For the wheel-side motor or wheel hub motor, convert the non-slip wheel-side motor or wheel hub motor speed to the speed of the drive shaft on the longitudinal axis of the vehicle according to the vehicle kinematics and dynamics theory and the steering wheel angle, and use it as the non-locked motor speed.

[0111] 4. Calculate the angular acceleration β0 of the non-locked motor speed and the average value of the change gradient γ0 in the current cycle.

[0112] 5. Calculate the motor angular acceleration change gradient γ in the next cycle according to formula ②, which is used to predict the motor speed change in the next cycle.

[0113] 6. Calculate the lower limit of the motor speed. The lower limit of the motor speed = max (predicted motor speed in the next cycle - safety threshold, the lowest motor speed during feedback). The predicted motor speed in the next cycle can be obtained according to formula ③: w = w0 + (β0 + γ) * dT. The safety threshold is to prevent the influence of factors such as motor speed fluctuations.

[0114] In the second stage, the motor controller MCU receives the target torque and speed lower limit sent by the vehicle controller VCU, and calculates the target torque and speed closed-loop target torque synchronously internally, with a theoretical cycle of less than or equal to 1ms. The control process of the motor in the motor controller MCU is as follows: Figure 4 shown.

[0115] 1. The motor controller MCU reads the target torque Tq and the lower speed limit w_low through Ethernet or CAN (Controller Area Network) signals.

[0116] 2. The motor controller MCU reads the motor speed signal of its own hard-wired signal and obtains the current speed w_a.

[0117] 3. Determine whether the current motor speed is less than the lower speed limit sent by the vehicle controller VCU. To prevent the motor controller MCU from frequently jumping back and forth between the activation and deactivation of the anti-lock function, a speed hysteresis is set to form hysteresis.

[0118] 4. When the current motor speed is less than or equal to the lower speed limit sent by the vehicle controller VCU, the motor speed closed-loop control is entered and the motor speed lower limit is used for control to prevent wheel locking; otherwise, when the current motor speed is greater than the lower speed limit sent by the vehicle controller VCU, the target torque sent by the vehicle controller VCU is used for torque control to prevent wheel locking.

[0119] It can be seen that in this embodiment, the signal sent by the vehicle controller VCU to the motor is based on the traditional control method of only sending the required torque, and a new motor speed lower limit is added. The vehicle controller VCU predicts the motor speed of the next cycle based on the target torque of the motor, the current motor speed and the change of the motor speed, and the execution cycle of the internal program of the vehicle controller VCU, and reserves a certain safety threshold to prevent the influence of motor speed fluctuations, etc., and sends the predicted motor speed of the next cycle + threshold and target torque to the motor controller MCU synchronously, such as Figure 3 When the motor speed does not exceed the lower limit, the motor controller MCU uses the target torque sent by the vehicle controller VCU to control the motor. When the motor speed exceeds the lower limit, the motor controller MCU uses the target torque calculated by the speed closed loop to control the motor, as shown in the figure. Figure 4 shown.

[0120] In addition, according to the records of some of the above embodiments, Figure 5 The signal flow of the wheel anti-lock control in some embodiments of the method, Figure 6This is the signal flow of the wheel anti-lock control in the existing method. It can be seen that compared with the existing method, this method can limit the anti-lock control of the wheel to the shorter transmission chain of the motor controller MCU-motor-wheel. The signal transmission loop is the motor controller MCU-motor (resolver)-motor controller MCU, and the program execution cycle of the motor controller MCU is less than or equal to 1ms. The anti-lock control loop theoretically only takes about 1 millisecond, which is much lower than the more than 30 milliseconds of traditional control. The motor speed change can be monitored and controlled in real time, and the high dynamic response requirements of the anti-lock control can be met. At the same time, this method uses the motor resolver signal to detect whether the vehicle is locked. The worst industry accuracy of this signal is generally less than 0.5° of the motor rotation angle. When converted to the wheel with a speed ratio of 9, it is still less than 0.06°, which is much larger than the 7.5° angle of the traditional wheel speed signal. The detection of wheel speed changes is more accurate, and there is no need for a model to estimate and calibrate the wheel speed. Figure 5 and Figure 6 In the figure, arrows indicate signal flow, the text on the arrows indicates the signal name, the value above the arrows indicates the communication cycle, the solid line indicates a hard-wired connection, and the dotted line indicates inter-controller Ethernet or CAN communication; It indicates the internal operating cycle of the controller below it, and the value above it indicates the size of the operating cycle; Indicates a mechanical connection.

[0121] In summary, the present application provides a wheel anti-lock control method, firstly obtaining the motor target torque and the motor speed lower limit calculated by the vehicle controller; then sending the motor target torque and the motor speed lower limit to the motor controller, and reading the motor speed of the motor controller itself, recorded as the current motor speed; then comparing the current motor speed with the motor speed lower limit received by the motor controller, and when the current motor speed is greater than the motor speed lower limit, using the motor target torque to perform wheel anti-lock control on the target vehicle; or, when the current motor speed is less than or equal to the motor speed lower limit, using the motor speed lower limit received by the motor controller to perform wheel anti-lock control on the target vehicle. Wherein, the target vehicle includes a vehicle determined in advance or in real time. It can be seen that the present method proposes a wheel anti-lock control scheme that uses the motor speed as a control signal and shortens the control path, which can effectively solve the problem that the control parameter transmission path in the traditional anti-lock control is too long when the electric feedback is large, which leads to easy wheel locking, and the problem that the vehicle is controlled by using the estimated parameters, which brings a large calibration work and a large error, and at the same time, it also brings more initiative to the vehicle longitudinal stability control for the OEM. In addition, this method can limit the anti-lock control of the wheel to the shorter transmission chain of the motor controller MCU-motor-wheel, and the signal transmission loop is limited to the motor controller MCU-motor (resolver)-motor controller MCU, and the program execution cycle of the motor controller MCU is less than or equal to 1ms. The anti-lock control loop theoretically takes only about 1 millisecond, which is much lower than the more than 30 milliseconds of traditional control. The motor speed change can be monitored and controlled in real time, which can meet the high dynamic response requirements of anti-lock control. At the same time, this method uses the motor resolver signal to detect whether the vehicle is locked. The worst industry accuracy of this signal is generally less than 0.5° of the motor rotation. It is still less than 0.06° when converted to the wheel with a speed ratio of 9, which is much larger than the 7.5° angle of the traditional wheel speed signal. The detection of wheel speed change is more accurate, and there is no need for a model to estimate and calibrate the wheel speed.

[0122] like Figure 7 As shown, the present application also provides a wheel anti-lock control device, the device comprising:

[0123] The data acquisition module 710 is used to obtain the motor target torque and the motor speed lower limit calculated by the vehicle controller;

[0124] The motor speed module 720 is used to send the motor target torque and the motor speed lower limit to the motor controller, and read the motor speed of the motor controller itself, which is recorded as the current motor speed;

[0125] A comparison module 730, configured to compare the current motor speed with the motor speed lower limit;

[0126] The anti-lock control module 740 is used to perform wheel anti-lock control on the target vehicle using the motor target torque when the current motor speed is greater than the motor speed lower limit; or, when the current motor speed is less than or equal to the motor speed lower limit, perform wheel anti-lock control on the target vehicle using the motor speed lower limit; wherein the target vehicle includes a vehicle determined in advance or in real time. As an example, the target vehicle in this embodiment may be a new energy vehicle, such as an electric vehicle.

[0127] It can be seen that this embodiment can effectively solve the problem that the control parameter transmission path in the traditional anti-lock control is too long when the electric feedback is large, which makes the wheel lock easy to occur, and the use of estimated parameters to control the vehicle brings about a large calibration work and a large error. At the same time, it also brings more initiative to the vehicle longitudinal stability control for the main engine manufacturer. In addition, this embodiment can limit the anti-lock control of the wheel to the shorter transmission chain of the motor controller MCU-motor-wheel, and the signal transmission loop is limited to the transmission chain of the motor controller MCU-motor (rotary transformer)*motor controller MCU; thus, the speed change of the motor can be monitored and controlled in real time, meeting the high dynamic response requirements of the anti-lock control.

[0128] In an exemplary embodiment, the process of the vehicle controller VCU calculating the lower limit of the motor speed includes:

[0129] Calculate the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , and calculate the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 ;

[0130] Determining whether the motor participates in regenerative braking of the target vehicle;

[0131] If the motor does not participate in the regenerative braking of the target vehicle, stopping the wheel anti-lock control of the target vehicle;

[0132] If the motor participates in the regenerative braking of the target vehicle, the motor speed corresponding to the non-locked wheel in the current cycle is obtained, and the motor speed angular acceleration β0 and the angular acceleration change gradient γ0 corresponding to the non-locked wheel in the current cycle are calculated;

[0133] According to the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 , and the angular acceleration change gradient γ0, calculate the motor angular acceleration change gradient γ in the next cycle, and we have:

[0134]

[0135] The motor speed lower limit w for the next cycle is calculated according to the motor angular acceleration change gradient γ for the next cycle.

[0136] According to the above records, specifically, the process of calculating the motor speed lower limit w of the next cycle according to the motor angular acceleration change gradient γ of the next cycle includes:

[0137] Obtain the average motor speed w0 corresponding to the current non-locked wheel and the execution cycle duration T of the vehicle controller;

[0138] According to the motor speed angular acceleration β0 corresponding to the non-locked wheel in the current cycle, the motor angular acceleration change gradient γ in the next cycle, the average motor speed w0 corresponding to the non-locked wheel in the current cycle, and the execution cycle duration T of the vehicle controller, the motor speed lower limit w in the next cycle is calculated, as follows:

[0139] w=w0+(β0+γ)*dT.

[0140] According to the above records, in an exemplary embodiment, before obtaining the average motor speed w0 corresponding to the current non-locked wheel, the device further includes: obtaining the vehicle wheel speed corresponding to the current non-locked wheel; converting the vehicle wheel speed corresponding to the current non-locked wheel into the motor speed corresponding to the current non-locked wheel, and calculating the average motor speed corresponding to the current non-locked wheel. It can be seen that in this embodiment, for the wheel-side motor or wheel hub motor, this embodiment converts the speed of the wheel-side motor or wheel hub motor that is not slipping into the speed of the drive shaft on the longitudinal axis of the vehicle according to the vehicle kinematics and dynamics theory and the steering wheel angle, and then uses it as the non-locked motor speed.

[0141] In an exemplary embodiment, after the target vehicle is subjected to wheel anti-lock control using the motor target torque, the device further includes: obtaining a preset speed value, and summing the preset speed value and the motor speed lower limit value to obtain a speed hysteresis value; comparing the current motor speed with the speed hysteresis value, and stopping the wheel anti-lock control of the target vehicle when the current motor speed is greater than the speed hysteresis value; or, when the current motor speed is less than or equal to the speed hysteresis value, maintaining the wheel anti-lock control of the target vehicle. It can be seen that this embodiment forms hysteresis by setting a speed hysteresis value, thereby preventing the motor controller MCU from frequently jumping back and forth between the activation and deactivation of the anti-lock function.

[0142] According to the above records, in an exemplary embodiment, the cycle length of the vehicle controller calculating the motor target torque and the motor speed lower limit is 10 milliseconds; the cycle length of reading the motor speed of the motor controller itself is less than or equal to 1 millisecond.

[0143] In another exemplary embodiment of the present application, the embodiment also provides a wheel anti-lock braking control device, which includes two stages, namely: a first stage in which a vehicle controller VCU calculates a motor target torque and a lower speed limit, and sends the calculated motor target torque and lower speed limit to a motor controller MCU; and a second stage after the motor controller receives the motor target torque and lower speed limit.

[0144] Among them, in the first stage, the vehicle controller VCU calculates and sends the motor target torque and speed lower limit to the motor controller MCU. The execution time of a single cycle of the vehicle controller VCU is 10ms. The process of the vehicle controller VCU calculating the motor speed lower limit is as follows Figure 3 Specifically, for a specific vehicle, the motor torque T q The relationship with angular acceleration β is: T q =J*β, taking the derivative of both sides of the equation, we can get dT q / dβ=J, J is the moment of inertia of the motor system, which is a constant; that is, the change in the motor target torque is proportional to the change in the motor angular acceleration. And in the signal at the vehicle controller VCU end, the torque change of the vehicle controller VCU is one cycle faster than the change in the motor speed. The target torque currently sent to the motor by the vehicle controller VCU needs to be read in the next cycle to be the motor speed generated by the torque of the current cycle. Based on this, according to the target torque change dT sent to the motor by the vehicle controller VCU in the previous cycle q-1 , and the ratio of the motor angular acceleration change γ0 (i.e. dβ) detected by the vehicle controller VCU in the current cycle Should be equal to the target torque change value dT sent to the motor by the vehicle controller VCU in the current cycle q0 , and the ratio of the motor angular acceleration change value γ in the next cycle, that is:

[0145]

[0146] but:

[0147]

[0148] Then the angular velocity of the motor in the next cycle is:

[0149] w=w0+β*dT=w0+(β0+γ)*dT③;

[0150] According to the above theory, the vehicle controller VCU can predict the lower limit value of the motor speed in the next program cycle of the vehicle controller VCU, and use this value as the lower limit value of the motor speed in the next program cycle of the vehicle controller VCU.

[0151] It can be seen from this that the logic of calculating the lower limit of the motor speed inside the vehicle controller VCU in this embodiment is:

[0152] 1. Calculate the target torque change dT of the VCU generator in the current cycle q0 and the target torque change gradient dT of the previous cycle q-1 ;

[0153] 2. Determine whether the motor is involved in feedback and braking. When the motor does not participate in the vehicle's feedback braking, the vehicle braking is pure hydraulic braking. At this time, the control is only completed inside the chassis controller. The control parameter transmission path is short, which is the chassis controller-brake hydraulic pipeline-wheel. The risk of wheel locking is relatively small. At this time, the vehicle controller VCU does not perform anti-lock control. When the motor participates in the vehicle's feedback braking and the motor speed is not negative (negative means that the motor drives the vehicle in the opposite direction of the gear), the anti-lock program controlled by the vehicle controller VCU is entered.

[0154] 3. After entering the anti-lock program controlled by the vehicle controller VCU, obtain the motor speed or vehicle wheel speed corresponding to the current non-locked wheel, convert it to the motor speed, and take the average value w0. For the wheel-side motor or wheel hub motor, convert the non-slip wheel-side motor or wheel hub motor speed to the speed of the drive shaft on the longitudinal axis of the vehicle according to the vehicle kinematics and dynamics theory and the steering wheel angle, and use it as the non-locked motor speed.

[0155] 4. Calculate the angular acceleration β0 of the non-locked motor speed and the average value of the change gradient γ0 in the current cycle.

[0156] 5. Calculate the motor angular acceleration change gradient γ in the next cycle according to formula ②, which is used to predict the motor speed change in the next cycle.

[0157] 6. Calculate the lower limit of the motor speed. The lower limit of the motor speed = max (predicted motor speed in the next cycle - safety threshold, the lowest motor speed during feedback). The predicted motor speed in the next cycle can be obtained according to formula ③: w = w0 + (β0 + γ) * dT. The safety threshold is to prevent the influence of factors such as motor speed fluctuations.

[0158] In the second stage, the motor controller MCU receives the target torque and speed lower limit sent by the vehicle controller VCU, and calculates the target torque and speed closed-loop target torque synchronously internally, with a theoretical cycle of less than or equal to 1ms. The control process of the motor in the motor controller MCU is as follows: Figure 4 shown.

[0159] 1. The motor controller MCU reads the target torque Tq and the lower speed limit w_low through Ethernet or CAN (Controller Area Network) signals.

[0160] 2. The motor controller MCU reads the motor speed signal of its own hard-wired signal and obtains the current speed w_a.

[0161] 3. Determine whether the current motor speed is less than the lower speed limit sent by the vehicle controller VCU. To prevent the motor controller MCU from frequently jumping back and forth between the activation and deactivation of the anti-lock function, a speed hysteresis is set to form hysteresis.

[0162] 4. When the current motor speed is less than or equal to the lower speed limit sent by the vehicle controller VCU, the motor speed closed-loop control is entered and the motor speed lower limit is used for control to prevent wheel locking; otherwise, when the current motor speed is greater than the lower speed limit sent by the vehicle controller VCU, the target torque sent by the vehicle controller VCU is used for torque control to prevent wheel locking.

[0163] It can be seen that in this embodiment, the signal sent by the vehicle controller VCU to the motor is based on the traditional control device that only sends the required torque, and a new motor speed lower limit is added. The vehicle controller VCU predicts the motor speed of the next cycle based on the target torque of the motor, the current motor speed and the change of the motor speed, and the execution cycle of the internal program of the vehicle controller VCU, and reserves a certain safety threshold to prevent the influence of motor speed fluctuations, etc., and sends the predicted motor speed of the next cycle + threshold and target torque to the motor controller MCU synchronously, such as Figure 3 When the motor speed does not exceed the lower limit, the motor controller MCU uses the target torque sent by the vehicle controller VCU to control the motor. When the motor speed exceeds the lower limit, the motor controller MCU uses the target torque calculated by the speed closed loop to control the motor, as shown in the figure. Figure 4 shown.

[0164] In addition, according to the records of some of the above embodiments, Figure 5 The signal flow of wheel anti-lock control in some embodiments is: Figure 6This is the signal flow of the existing wheel anti-lock control. It can be seen that compared with the existing device, this device can limit the anti-lock control of the wheel to the shorter transmission chain of motor controller MCU-motor-wheel. The signal transmission loop is motor controller MCU-motor (resolver)-motor controller MCU, and the program execution cycle of the motor controller MCU is less than or equal to 1ms. The anti-lock control loop theoretically only takes about 1 millisecond, which is much lower than the more than 30 milliseconds of traditional control. The motor speed change can be monitored and controlled in real time, and the high dynamic response requirements of anti-lock control can be met. At the same time, this device uses the motor resolver signal to detect whether the vehicle is locked. The worst industry accuracy of this signal is generally less than 0.5° of the motor rotation angle. When converted to the wheel with a speed ratio of 9, it is still less than 0.06°, which is much larger than the 7.5° angle of the traditional wheel speed signal. The detection of wheel speed changes is more accurate, and there is no need for a model to estimate and calibrate the wheel speed. Figure 5 and Figure 6 In the figure, arrows indicate signal flow, the text on the arrows indicates the signal name, the value above the arrows indicates the communication cycle, the solid line indicates a hard-wired connection, and the dotted line indicates inter-controller Ethernet or CAN communication; It indicates the internal operating cycle of the controller below it, and the value above it indicates the size of the operating cycle; Indicates a mechanical connection.

[0165] In summary, the present application provides a wheel anti-lock control device, which first obtains the motor target torque and the motor speed lower limit calculated by the vehicle controller; then sends the motor target torque and the motor speed lower limit to the motor controller, and reads the motor speed of the motor controller itself, which is recorded as the current motor speed; then compares the current motor speed with the motor speed lower limit received by the motor controller, and when the current motor speed is greater than the motor speed lower limit, uses the motor target torque to perform wheel anti-lock control on the target vehicle; or, when the current motor speed is less than or equal to the motor speed lower limit, uses the motor speed lower limit received by the motor controller to perform wheel anti-lock control on the target vehicle. Wherein, the target vehicle includes a vehicle determined in advance or in real time. It can be seen that the present device proposes a wheel anti-lock control scheme that uses the motor speed as a control signal and shortens the control path, which can effectively solve the problem that the control parameter transmission path in the traditional anti-lock control is too long when the electric feedback is large, which makes it easy to lock the wheel, and the use of estimated parameters to control the vehicle brings about a large calibration work and a large error. At the same time, it also brings more initiative to the vehicle longitudinal stability control for the main engine manufacturer. In addition, the device can limit the anti-lock control of the wheel to the shorter transmission chain of the motor controller MCU-motor-wheel, and the signal transmission loop is limited to the motor controller MCU-motor (resolver)-motor controller MCU, and the program execution cycle of the motor controller MCU is less than or equal to 1ms. The anti-lock control loop theoretically takes only about 1 millisecond, which is much lower than the more than 30 milliseconds of traditional control. The motor speed change can be monitored and controlled in real time, which can meet the high dynamic response requirements of anti-lock control. At the same time, the device uses the motor resolver signal to detect whether the vehicle is locked. The worst industry accuracy of this signal is generally less than 0.5° of the motor rotation. It is still less than 0.06° when converted to the wheel with a speed ratio of 9, which is much larger than the 7.5° angle of the traditional wheel speed signal. The detection of wheel speed changes is more accurate, and there is no need for a model to estimate and calibrate the wheel speed.

[0166] It should be noted that the wheel anti-lock control device provided in the above embodiment and the wheel anti-lock control method provided in the above embodiment belong to the same concept, wherein the specific manner in which each module and unit performs the operation has been described in detail in the method embodiment, and will not be repeated here. In actual application, the wheel anti-lock control device provided in the above embodiment can distribute the above functions to different functional modules as needed, that is, divide the internal structure of the system into different functional modules to complete all or part of the functions described above, and this is not limited here.

[0167] An embodiment of the present application also provides a wheel anti-lock braking control device, comprising: one or more processors; a storage device for storing one or more programs, when the one or more programs are executed by the one or more processors, the wheel anti-lock braking control device implements the wheel anti-lock braking control method provided in the above-mentioned embodiments.

[0168] Figure 8 The structure diagram of the computer system suitable for implementing the wheel anti-lock braking control device of the embodiment of the present application is shown. It should be noted that: Figure 8 The computer system 1000 of the wheel anti-lock braking control device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0169] like Figure 8 As shown, the computer system 1000 includes a central processing unit (CPU) 1001, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 1002 or the program loaded from the storage part 1008 to the random access memory (RAM) 1003, such as executing the method described in the above embodiment. In the RAM 1003, various programs and data required for system operation are also stored. The CPU 1001, the ROM 1002 and the RAM 1003 are connected to each other through the bus 1004. The input / output (I / O) interface 1005 is also connected to the bus 1004.

[0170] The following components are connected to the I / O interface 1005: an input section 1006 including a keyboard, a mouse, etc.; an output section 1007 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 1008 including a hard disk, etc.; and a communication section 1009 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 1009 performs communication processing via a network such as the Internet. A drive 1010 is also connected to the I / O interface 1005 as needed. A removable medium 1011, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 1010 as needed, so that a computer program read therefrom is installed into the storage section 1008 as needed.

[0171] In particular, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication section 1009, and / or installed from a removable medium 1011. When the computer program is executed by a central processing unit (CPU) 1001, various functions defined in the system of the present application are executed.

[0172] It should be noted that the computer-readable medium shown in the embodiment of the present application can be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media can include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, wherein a computer-readable computer program is carried. This propagated data signal can take a variety of forms, including but not limited to an electromagnetic signal, an optical signal, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate or transmit a program for use by or in conjunction with an instruction execution system, apparatus or device. A computer program contained on a computer-readable medium may be transmitted using any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0173] The flowchart and block diagram in the accompanying drawings illustrate the possible architecture, functions and operations of the system, method and computer program product according to various embodiments of the present application. Wherein, each box in the flowchart or block diagram can represent a module, a program segment, or a part of the code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0174] The units involved in the embodiments described in this application may be implemented by software or hardware, and the units described may also be set in a processor. The names of these units do not, in some cases, constitute limitations on the units themselves.

[0175] Another aspect of the present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor of a computer, the computer executes the wheel anti-lock braking control method as described above. The computer-readable storage medium may be included in the wheel anti-lock braking control device described in the above embodiment, or may exist independently without being assembled into the wheel anti-lock braking control device.

[0176] Another aspect of the present application also provides a computer program product or a computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the wheel anti-lock braking control method provided in each of the above embodiments.

[0177] The above embodiments are merely illustrative of the principles and effects of the present application, and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A wheel anti-lock braking control method, characterized in that: The method comprises the following steps: Obtain the motor target torque and motor speed lower limit calculated by the vehicle controller; Sending the motor target torque and the motor speed lower limit to the motor controller, and reading the motor speed of the motor controller itself, which is recorded as the current motor speed; Comparing the current motor speed with the motor speed lower limit; When the current motor speed is greater than the motor speed lower limit, the motor target torque is used to perform wheel anti-lock control on the target vehicle; or, when the current motor speed is less than or equal to the motor speed lower limit, the motor speed lower limit is used to perform wheel anti-lock control on the target vehicle; wherein the target vehicle includes a vehicle determined in advance or in real time; The process of the vehicle controller calculating the lower limit value of the motor speed includes: Calculate the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , and calculate the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 ; Determining whether the motor participates in regenerative braking of the target vehicle; If the motor does not participate in the regenerative braking of the target vehicle, stopping the wheel anti-lock control of the target vehicle; If the motor participates in the regenerative braking of the target vehicle, the motor speed corresponding to the non-locked wheel in the current cycle is obtained, and the motor speed angular acceleration β0 and the angular acceleration change gradient γ0 corresponding to the non-locked wheel in the current cycle are calculated; According to the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 , and the angular acceleration change gradient γ0, calculate the motor angular acceleration change gradient γ in the next cycle, and we have: The motor speed lower limit w for the next cycle is calculated according to the motor angular acceleration change gradient γ for the next cycle.

2. The wheel anti-lock braking control method according to claim 1, characterized in that: The process of calculating the motor speed lower limit value w of the next cycle according to the motor angular acceleration change gradient γ of the next cycle includes: Obtain the average motor speed w0 corresponding to the current non-locked wheel and the execution cycle duration T of the vehicle controller; According to the motor speed angular acceleration β0 corresponding to the non-locked wheel in the current cycle, the motor angular acceleration change gradient γ in the next cycle, the average motor speed w0 corresponding to the non-locked wheel in the current cycle, and the execution cycle duration T of the vehicle controller, the motor speed lower limit w in the next cycle is calculated, as follows: w=w0+(β0+γ)*dT.

3. The wheel anti-lock braking control method according to claim 2, characterized in that: Before obtaining the average motor speed w0 corresponding to the current non-locked wheel, the method further includes: Get the vehicle wheel speed corresponding to the current non-locked wheel; The vehicle wheel speed corresponding to the current non-locked wheel is converted into the motor speed corresponding to the current non-locked wheel, and the average motor speed corresponding to the current non-locked wheel is calculated.

4. The wheel anti-lock braking control method according to any one of claims 1 to 3, characterized in that: After performing wheel anti-lock control on the target vehicle using the motor target torque, the method further includes: Obtaining a preset speed value, and summing the preset speed value and the motor speed lower limit value to obtain a speed hysteresis value; The current motor speed is compared with the speed hysteresis value, and when the current motor speed is greater than the speed hysteresis value, the wheel anti-lock control of the target vehicle is stopped; or when the current motor speed is less than or equal to the speed hysteresis value, the wheel anti-lock control of the target vehicle is maintained.

5. The wheel anti-lock braking control method according to any one of claims 1 to 3, characterized in that: The cycle time for the vehicle controller to calculate the motor target torque and the motor speed lower limit is 10 milliseconds; The cycle duration of reading the motor speed of the motor controller itself is less than or equal to 1 millisecond.

6. The wheel anti-lock braking control method according to any one of claims 1 to 3, characterized in that: The target vehicles include: new energy vehicles.

7. A wheel anti-lock control device, characterized in that: The device comprises: The data acquisition module is used to obtain the motor target torque and the motor speed lower limit calculated by the vehicle controller; A motor speed module, used for sending the motor target torque and the motor speed lower limit to the motor controller, and reading the motor speed of the motor controller itself, which is recorded as the current motor speed; A comparison module, used for comparing the current motor speed with the motor speed lower limit; an anti-lock control module, configured to perform wheel anti-lock control on a target vehicle using the motor target torque when the current motor speed is greater than the motor speed lower limit; or, when the current motor speed is less than or equal to the motor speed lower limit, perform wheel anti-lock control on the target vehicle using the motor speed lower limit; wherein the target vehicle includes a vehicle determined in advance or in real time; The process of calculating the lower limit value of the motor speed by the vehicle controller in the data acquisition module includes: Calculate the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , and calculate the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 ; Determining whether the motor participates in regenerative braking of the target vehicle; If the motor does not participate in the regenerative braking of the target vehicle, stopping the wheel anti-lock control of the target vehicle; If the motor participates in the regenerative braking of the target vehicle, the motor speed corresponding to the non-locked wheel in the current cycle is obtained, and the motor speed angular acceleration β0 and the angular acceleration change gradient γ0 corresponding to the non-locked wheel in the current cycle are calculated; According to the motor target torque change gradient dT of the vehicle controller in the current cycle q0 , the motor target torque change gradient dT of the vehicle controller in the previous cycle q-1 , and the angular acceleration change gradient γ0, calculate the motor angular acceleration change gradient γ in the next cycle, and we have: The motor speed lower limit w for the next cycle is calculated according to the motor angular acceleration change gradient γ for the next cycle.

8. The wheel anti-lock braking control device according to claim 7, characterized in that: The process of calculating the motor speed lower limit value w of the next cycle according to the motor angular acceleration change gradient γ of the next cycle includes: Obtain the average motor speed w0 corresponding to the current non-locked wheel and the execution cycle duration T of the vehicle controller; According to the motor speed angular acceleration β0 corresponding to the non-locked wheel in the current cycle, the motor angular acceleration change gradient γ in the next cycle, the average motor speed w0 corresponding to the non-locked wheel in the current cycle, and the execution cycle duration T of the vehicle controller, the motor speed lower limit w in the next cycle is calculated, as follows: w=w0+(β0+γ)*dT.

9. A wheel anti-lock control device, characterized in that: The device comprises: one or more processors; A storage device for storing one or more programs, when the one or more programs are executed by the one or more processors, enables the device to implement the wheel anti-lock braking control method as described in any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor of a computer, the computer is caused to execute the wheel anti-lock braking control method according to any one of claims 1 to 6.

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