Vehicle control method, controller and vehicle

Abstract

The embodiment of the present invention provides a vehicle control method, a controller and a vehicle, including: when it is determined that the mechanical brake system of the vehicle fails, obtaining the pedaling parameters of the brake pedal of the vehicle; determining the braking torque value according to the pedaling parameters; and controlling the electric brake system of the vehicle to output the required braking torque according to the braking torque value. In the embodiment of the present invention, after the brake boosting system of the vehicle fails, the pedaling parameters of the brake pedal of the vehicle can be collected by the domain controller, and the appropriate braking torque value can be determined according to the pedaling parameters, so that the power motor of the vehicle outputs the braking torque according to the braking torque value. Therefore, after the brake boosting system of the vehicle fails, the power motor can assist the vehicle in deceleration, thereby improving the braking performance of the vehicle, strengthening the driver's ability to control the vehicle after the brake boosting fails, and reducing the probability of traffic accidents.

Description

Technical Field

[0001] The present invention relates to the field of automobile technology, and in particular to a vehicle control method, a controller and a vehicle. Background Art

[0002] With the popularity of electric vehicles, in order to enable electric vehicles to better provide other intelligent services such as autonomous driving, more and more vehicles are beginning to use wire-controlled brake assist systems such as iBooster as the vehicle's brake assist system.

[0003] Under normal circumstances, there is no rigid connection between the brake pedal and the brake caliper in the wire-controlled brake power-assist system. The main control computer of the power-assist system will allocate the ratio of mechanical braking torque to electric braking torque according to the brake pedal signal, and the power-assist power source will drive the brake caliper for braking under the action of the brake pedal signal. When a failure occurs in the wire-controlled brake power-assist system, a rigid connection will be established between the brake pedal and the brake caliper. At this time, the power-assist power source cannot provide a power-assist effect, and the braking torque generated by the brake caliper is entirely generated by the force with which the driver steps on the brake pedal.

[0004] In the prior art, when a brake-by-wire assist system fails, the assist source cannot provide assist effect, which makes it difficult for the driver to step on the brakes, resulting in insufficient braking torque of the vehicle, which can easily cause driving hazards. Summary of the invention

[0005] In view of this, the present invention aims to provide a vehicle control method, a controller and a vehicle to solve the problem of insufficient vehicle braking torque after a failure of a brake assist system controlled by a wire in the prior art.

[0006] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0007] A vehicle control method, the method comprising:

[0008] When it is determined that a mechanical brake system of the vehicle fails, obtaining a stepping parameter of a brake pedal of the vehicle;

[0009] determining a braking torque value according to the pedaling parameter;

[0010] The electric brake system of the vehicle is controlled to output a required braking torque according to the braking torque value.

[0011] A vehicle control device, comprising:

[0012] An acquisition module, used for acquiring a stepping parameter of a brake pedal of the vehicle when it is determined that a mechanical brake system of the vehicle fails;

[0013] A torque module, used for determining a braking torque value according to the pedaling parameter;

[0014] The braking module is used to control the electric braking system of the vehicle to output a required braking torque according to the braking torque value.

[0015] A vehicle comprises the above-mentioned domain controller.

[0016] Compared with the prior art, the vehicle control method, controller and vehicle described in the present invention have the following advantages:

[0017] In summary, an embodiment of the present invention provides a vehicle control method, including: when it is determined that a mechanical brake system of the vehicle fails, obtaining the pedaling parameters of the brake pedal of the vehicle; determining the braking torque value according to the pedaling parameters; and controlling the electric brake system of the vehicle to output the required braking torque according to the braking torque value. In an embodiment of the present invention, after a failure occurs in the brake boosting system of the vehicle, the pedaling parameters of the brake pedal of the vehicle can be collected by the vehicle controller, and a suitable braking torque value can be determined according to the pedaling parameters, so that the power motor of the vehicle outputs the braking torque according to the braking torque value. Therefore, after a failure occurs in the brake boosting system of the vehicle, the power motor can assist the vehicle in deceleration, thereby improving the braking performance of the vehicle, strengthening the driver's ability to control the vehicle after the brake boosting fails, and reducing the probability of traffic accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0019] Figure 1 A flow chart of steps of a vehicle control method provided by an embodiment of the present invention;

[0020] Figure 2 A conventional braking system architecture diagram provided by an embodiment of the present invention;

[0021] Figure 3 A flowchart of another vehicle control method provided by an embodiment of the present invention;

[0022] Figure 4 A structural block diagram of a vehicle control device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0024] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0025] Reference Figure 1, showing a flow chart of steps of a vehicle control method according to an embodiment of the present invention.

[0026] A vehicle control method provided in an embodiment of the present invention is applied to a vehicle control unit (VCU), a power domain controller (PDC), or other controllers that control the vehicle power system. The power domain controller is obtained by integrating the vehicle control unit, the motor controller, and the battery management system (BMS). Therefore, the method provided in the embodiment of the present application can be directly applied to the power and controller, and can also be applied to the vehicle control unit, the motor controller, and the battery management system.

[0027] Step S101, when it is determined that a mechanical brake system of a vehicle fails, obtaining a stepping parameter of a brake pedal of the vehicle.

[0028] Reference Figure 2 , shows a conventional braking system architecture diagram according to an embodiment of the present invention, such as Figure 2 As shown, the total braking torque module 202 of the brake boost system 201 can obtain the driver's braking request. The total braking torque module 202 calculates the total braking torque required by the vehicle according to the driver's braking request, and then sends the total braking torque to the allocation module 203. The allocation module 203 allocates the mechanical braking torque to the mechanical braking unit 204 according to the total braking torque, and allocates the electric braking torque to the vehicle controller 205. The mechanical braking unit 204 controls the brake caliper 208 to clamp the brake disc to generate mechanical braking torque. The vehicle controller 205 sends an electric braking request to the motor controller 206, and the motor controller 206 controls the drive motor 207 to output the electric braking torque. However, in the event of a failure, the brake boost system cannot continue to allocate mechanical braking torque and electric braking torque to the vehicle according to the user's braking request, resulting in the failure of the vehicle's mechanical brake boost function and electric braking function at the same time. It should be noted that in the embodiment of the present application, unless otherwise specified, the braking torque represents the electric braking torque generated by the vehicle's power motor.

[0029] The brake assist system can transmit data to the domain controller. The brake assist system can monitor its own operation and send a brake assist system fault signal to the domain controller in the event of a fault. The domain controller can receive the fault signal from the brake assist system to determine that the vehicle's brake assist system has a fault. After the domain controller determines that the vehicle's brake assist system has a fault, it can turn on the motor brake assist function and obtain the vehicle's brake pedal stepping depth value and / or brake pedal stepping pressure value.

[0030] When the brake-by-wire system fails, a force transmission structure is established between the brake pedal and the brake caliper through movable mechanisms such as solenoid valves, air valves or motors, so that the driver's pedal force on the brake pedal can be directly transmitted to the brake caliper, thereby providing braking torque for the vehicle through manpower. However, since the brake system has no power at this time, the driver needs to apply great force to the brake pedal to meet the vehicle's demand for braking torque, resulting in a serious decline in the vehicle's braking performance.

[0031] The pedaling parameter may be the pedaling depth of the brake pedal. The pedaling depth of the brake pedal is used to indicate the extent to which the brake pedal is stepped on. It may refer to the proportion of the travel of the brake pedal under the pedaling force of the driver to the total travel. For example, when the brake pedal is not stepped on, its pedaling depth is 0%, and when the brake pedal is fully stepped on, its pedaling depth is 100%. It should be noted that the pedaling depth can be determined based on the displacement of the brake pedal or the rotation angle of the brake pedal around a fixed axis. Specifically, the domain controller can determine the depth to which the brake pedal is stepped based on a displacement sensor or an angle sensor provided on the brake pedal.

[0032] The stepping parameter may also be the stepping pressure of the brake pedal. The stepping pressure value of the brake pedal is used to indicate the magnitude of the force applied to the brake pedal when the driver steps on the brake pedal. When the driver applies the same direction and magnitude of stepping pressure to the brake pedal, the stepping depth of the brake pedal is not necessarily the same due to different vehicle conditions (such as changes in the thickness of the brake pad, changes in the height of the brake pedal, etc.). Therefore, the stepping depth of the brake pedal may not necessarily accurately reflect the driver's intention to request the braking force. Furthermore, the driver's intention to request the braking force can also be reflected by the stepping pressure of the brake pedal. Specifically, a pressure sensor can be set on the brake pedal to directly obtain the force applied by the driver to the brake pedal. When the vehicle operating conditions change and the accelerator pedal is stuck, the driver's braking intention can be determined by the force applied by the driver to the accelerator pedal.

[0033] Step S102, determining a braking torque value according to the pedaling parameter.

[0034] When the brake pedal's depression depth value is large, the driver generally hopes to obtain a larger braking torque and braking acceleration; when the brake pedal's depression pressure value is large, the driver also systemically obtains a larger braking torque and braking acceleration.

[0035] Therefore, after obtaining the pedaling depth value or the pedaling pressure value, the corresponding braking torque value can be calculated according to the pedaling depth value or the pedaling pressure value, wherein the braking torque value increases with the increase of the pedaling depth value, or the braking torque value increases with the increase of the pedaling pressure value.

[0036] The braking torque value is opposite to the driving torque value that drives the vehicle forward. The braking torque value may represent the braking torque value that the power motor of the vehicle needs to output, and the braking torque value may also represent the braking torque value acting on the tires of the vehicle.

[0037] Step S103 , controlling the electric brake system of the vehicle to output a required braking torque according to the braking torque value.

[0038] In some vehicles, the domain controller cannot directly control the vehicle's power motor, so the domain controller needs to send a torque request to the motor controller, and then the motor controller directly controls the power motor to output the torque required by the torque request.

[0039] Therefore, when the execution entity is a domain controller, the domain controller can send a torque request including a braking torque value to the motor controller, and then the motor controller adjusts the input voltage and / or current of the power motor so that the power motor outputs a braking torque that matches the braking torque value in the torque request.

[0040] Since the power domain controller is obtained by integrating the domain controller, motor controller and battery management system, that is to say, the power domain controller can directly control the power motor.

[0041] Therefore, when the execution subject is a power domain controller, the power domain controller can directly adjust the input voltage and / or current of the power motor so that the power motor outputs a braking torque that matches the braking torque value.

[0042] When the power motor outputs a matching braking torque according to the braking torque value, the power motor can play a reverse drag role on the vehicle, causing the vehicle to slow down. When the braking torque value is larger, the braking torque output by the power motor is larger, the reverse drag role played by the power motor on the vehicle is more obvious, and the speed of the vehicle decreases faster, that is, the acceleration received by the vehicle is greater in the opposite direction of the vehicle's travel.

[0043] It should be noted that when the braking torque value represents the torque value that the vehicle's power motor needs to output, the vehicle's power motor can directly output a braking torque equivalent to the braking torque value. When the braking torque value represents the torque on the wheel, the braking torque that the power motor needs to output to match the braking torque value needs to be calculated based on the transmission ratio of the vehicle's transmission system. The transmission ratio refers to the ratio of the power motor speed to the corresponding wheel speed.

[0044] For example, after calculation, a vehicle with a transmission ratio of 10 requires a wheel braking torque value of 1000 Nm. At this time, the braking torque to be output by the vehicle's power motor is 1000 / 10=100 Nm.

[0045] In summary, an embodiment of the present invention provides a vehicle control method, including: when it is determined that a mechanical brake system of the vehicle fails, obtaining the pedaling parameters of the brake pedal of the vehicle; determining the braking torque value according to the pedaling parameters; and controlling the electric brake system of the vehicle to output the required braking torque according to the braking torque value. In an embodiment of the present invention, after a failure occurs in the brake boosting system of the vehicle, the pedaling parameters of the brake pedal of the vehicle can be collected by a domain controller, and a suitable braking torque value can be determined according to the pedaling parameters, so that the power motor of the vehicle outputs the braking torque according to the braking torque value. Therefore, after a failure occurs in the brake boosting system of the vehicle, the power motor can assist the vehicle in deceleration, thereby improving the braking performance of the vehicle, strengthening the driver's ability to control the vehicle after the brake boosting fails, and reducing the probability of traffic accidents.

[0046] Reference Figure 3 , shows a step flow chart of another vehicle control method described in an embodiment of the present invention.

[0047] Step S301, when it is determined that a mechanical brake system of the vehicle fails, obtaining a stepping parameter of the brake pedal of the vehicle.

[0048] This step can refer to step S101 and will not be described in detail in this embodiment of the present application.

[0049] Step S302, determining whether the pedaling parameters are valid.

[0050] In order to determine whether the pedaling parameters are real and valid, the domain controller needs to determine whether the sensor that generates the corresponding signal is working properly. Specifically, the sensor can monitor its own status and broadcast the status bit information in real time through the vehicle's bus. Therefore, the domain controller can monitor the status bit information on the bus to determine whether the status bit information corresponding to the pedaling parameter indicates that the pedaling parameter is invalid. The domain controller can also determine whether the pedaling parameter is valid in other ways, such as monitoring the corresponding sensor operating voltage and operating current, regularly shaking hands with the sensor, etc. The embodiment of the present application does not specifically limit the method for determining sensor failure, and technicians can flexibly choose according to actual needs.

[0051] Furthermore, the domain controller can not only determine whether the pedaling parameters are real and effective by determining whether the sensor fails, but can also verify the determined pedaling parameters to determine whether the pedaling parameters are real and effective.

[0052] Specifically, since the change of the pedaling depth of the brake pedal requires a process, if the pedaling parameter changes too quickly and exceeds the physical limit, it can be considered that there is a jump error in the pedaling parameter. Therefore, in the case where the pedaling parameter includes the pedaling depth value, the pedaling depth value can be judged whether it is real and valid by the change amount of the pedaling depth value of the brake pedal within the first preset time. When the change amount of the pedaling depth value within the first preset time exceeds the first threshold, it can be determined that the pedaling depth value is invalid. When the change amount of the pedaling depth value within the first preset time is less than the first threshold, it can be determined that the pedaling depth value is valid. For example, the first preset time can be set to 0.01 seconds, and the first threshold can be set to 50%. Within 0.01 seconds, if the change amount of the pedaling depth value exceeds 50%, it can be determined that the pedaling depth value is invalid. In the case where the pedaling parameter includes the pedaling pressure value, the pedaling pressure value can be judged whether it is real and valid by the change amount of the pedaling pressure value of the brake pedal within the second preset time. When the change amount of the pedaling pressure value within the second preset time exceeds the second threshold, it can be determined that the pedaling pressure value is invalid. When the change amount of the pedaling pressure value within the second preset time is less than the second threshold, it can be determined that the pedaling pressure value is valid. For example, the second preset time may be set to 0.01 seconds, and the second threshold may be set to 100 N. If the change in the pedaling pressure value exceeds 100 N within 0.01 seconds, it may be determined that the pedaling pressure value is invalid.

[0053] Since normal pedaling parameters are within a normal range, it is also possible to determine whether the pedaling parameters are valid by setting a threshold value. When the pedaling parameters include a pedaling pressure value, a pressure range interval of the pedaling pressure value can be set. When the pedaling pressure value is within the pressure range interval, the pedaling pressure value is determined to be valid. When the pedaling pressure value is not within the pressure range interval, the pedaling pressure value is determined to be invalid. When the pedaling parameters include a pedaling depth value, a depth range interval of the pedaling depth value can be set. When the pedaling depth value is within the depth range interval, the pedaling depth value is determined to be valid. When the pedaling depth value is not within the depth range interval, the pedaling depth value is determined to be invalid.

[0054] Furthermore, if it is determined that the pedaling parameter is valid, the braking torque value can be further determined based on the pedaling parameter.

[0055] The embodiment of the present application can avoid the situation where the braking torque value is erroneously determined according to the wrong pedaling parameters by determining the validity of the pedaling parameters, thereby avoiding the provision of electric braking torque to the vehicle according to the wrong pedaling parameters, thereby improving the safety of vehicle driving.

[0056] Optionally, step S302 may include:

[0057] Sub-step S3021, obtaining the status bit information corresponding to the pedaling parameter.

[0058] The status bit information of the pedaling parameter is used to indicate whether the pedaling parameter is valid. When the vehicle detects that a fault occurs in the generation process of the pedaling parameter, the status bit information of the pedaling parameter indicates that the pedaling parameter is currently wrong or unavailable, that is, the pedaling parameter is invalid. For example, in the case where the pedaling parameter is the pedaling depth, the status bit information of the pedaling parameter is used to indicate whether a fault occurs in the pedaling depth signal.

[0059] Sub-step S3022, determining whether the status bit information is the same as the first preset value.

[0060] The state bit information of the stepping parameter generally includes two values, one of which is used to indicate that the stepping parameter is invalid, and the other is used to indicate that the stepping parameter is valid. The first preset value is the state bit information value indicating that the stepping parameter is valid. For example, the state bit information of the stepping parameter may include 1 and 0, wherein 1 indicates that the stepping parameter is valid, and 0 indicates that the stepping parameter is invalid. In this case, the first preset value is 1.

[0061] Sub-step S3023, when the status bit information is the same as the first preset value, it is determined that the pedaling parameter is valid.

[0062] The status bit information of the pedaling parameter is acquired in real time, and the status bit information of the pedaling parameter is continuously compared with the first preset value. When the comparison result shows that the status bit information of the pedaling parameter is the same as the first preset value, it is determined that the pedaling parameter is valid.

[0063] Sub-step S3024: when the status bit information is different from the first preset value, it is determined that the pedaling parameter is invalid.

[0064] The status bit information of the pedaling parameter is acquired in real time, and the status bit information of the pedaling parameter is continuously compared with the first preset value. When the comparison result shows that the status bit information of the pedaling parameter is different from the first preset value, it is determined that the pedaling parameter is invalid.

[0065] Step S303: determining a braking torque value according to the pedaling parameter.

[0066] Optionally, step S303 may include:

[0067] Sub-step S3031, when the pedaling parameters are valid, the braking torque value is determined according to the pedaling depth value of the brake pedal, wherein the pedaling depth value and the braking torque value have a linear correspondence, or the braking torque value is determined according to the pedaling pressure value of the brake pedal, wherein the pedaling pressure value and the braking torque value have a linear correspondence.

[0068] When the brake pedal's depression depth value is large, the driver generally hopes to obtain a larger braking torque and braking acceleration; when the brake pedal's depression pressure value is large, the driver also systemically obtains a larger braking torque and braking acceleration.

[0069] Therefore, the linear first correspondence between the pedaling depth value and the braking torque value, or the linear second correspondence between the pedaling pressure value and the braking torque value can be determined in advance through experiments and experience, and the first correspondence or the second correspondence can be saved in the domain controller. The braking torque value in the first correspondence increases with the increase of the pedaling depth value, and the braking torque value in the second correspondence increases with the increase of the pedaling pressure value.

[0070] After the pedaling depth value or the pedaling pressure value is obtained, the corresponding braking torque value may be determined from the first corresponding relationship according to the pedaling depth value, or the corresponding braking torque value may be determined from the second corresponding relationship according to the pedaling depth value.

[0071] The braking torque value is opposite to the driving torque value that drives the vehicle forward. The braking torque value may represent the braking torque value that the power motor of the vehicle needs to output, and the braking torque value may also represent the braking torque value acting on the tires of the vehicle.

[0072] Sub-step S3032, when the pedaling parameter is invalid, obtaining the switch information of the brake switch of the vehicle.

[0073] If it is determined that the sensor of the pedaling parameter is abnormal or the pedaling parameter is invalid, the domain controller may determine that the pedaling parameter cannot reflect the actual situation, and the braking torque value cannot be determined based on the pedaling parameter.

[0074] Since the vehicle also has a brake switch, the brake switch can indicate whether the vehicle has braked. For example, when the driver steps on the brake or pulls up the handbrake, the vehicle's brake switch is in the braking state. Usually, the brake switch is used to control the on and off of the brake lights. When the brake switch is in the braking state, the brake lights are on, and when the brake switch is in the non-braking state, the brake lights are off. Therefore, it is possible to determine whether the driver has a braking intention based on the state of the brake switch. Furthermore, when the pedaling parameter fails, it is possible to determine whether to output the braking torque value based on the state of the brake switch.

[0075] Sub-step S3033: when it is determined according to the switch information that the brake switch is triggered, an emergency parking operation is performed according to a first preset parking strategy.

[0076] When the domain controller determines that the brake switch is triggered, that is, the brake switch indicates that the vehicle's accelerator pedal is pressed, the vehicle needs to brake. At this time, due to the failure of the pedaling parameters, the domain controller cannot determine the pedaling depth and pedaling pressure of the brake pedal. Therefore, to ensure vehicle safety, the first preset parking strategy is to control the vehicle's drive motor to brake with the maximum braking force to stop the vehicle as soon as possible.

[0077] Optionally, sub-step S3033 may include:

[0078] Sub-step A1, obtaining the driving speed value of the vehicle.

[0079] The angular velocity values ​​of each wheel of the vehicle can be obtained by an angular velocity sensor installed on the wheel axle or tire, and then the driving speed value of the vehicle can be calculated based on the angular velocity values ​​of each wheel. The driving speed value of the vehicle can also be calculated using a satellite positioning signal. The embodiment of the present invention does not specifically limit the method for obtaining the driving speed of the vehicle.

[0080] Sub-step A2, determining a maximum braking torque corresponding to the driving speed value from a first preset table, and controlling the electric braking system of the vehicle to output the maximum braking torque to perform an emergency parking operation.

[0081] The magnitude of the braking torque value can be determined from a first preset table according to the vehicle's driving speed value, wherein the first preset table includes a correspondence between the vehicle's driving speed value and the maximum braking torque value. The maximum braking torque value corresponding to the vehicle at different driving speeds can be determined in advance based on experiments and experience. The setting principle of the maximum braking torque value in the first preset table is that the maximum braking torque value corresponding to a certain driving speed value is the maximum drag torque that the vehicle's drive motor can provide at the driving speed value.

[0082] Sub-step S3034: when it is determined according to the switch information that the brake switch is not triggered, a smooth parking operation is performed according to a second preset parking strategy.

[0083] The second preset parking strategy is to make the driving motor of the vehicle output a smaller braking torque value when the accelerator pedal of the vehicle is not depressed.

[0084] Optionally, sub-step S3034 may include:

[0085] Sub-step B1, obtaining the driving speed value of the vehicle.

[0086] The angular velocity values ​​of each wheel of the vehicle can be obtained by an angular velocity sensor installed on the wheel axle or tire, and then the driving speed value of the vehicle can be calculated based on the angular velocity values ​​of each wheel. The driving speed value of the vehicle can also be calculated using a satellite positioning signal. The embodiment of the present invention does not specifically limit the method for obtaining the driving speed of the vehicle.

[0087] Sub-step B2, determining a smooth braking torque corresponding to the driving speed value from a second preset table, and controlling the electric braking system of the vehicle to output the smooth braking torque to perform a smooth parking operation.

[0088] The magnitude of the braking torque value can be determined from a second preset table according to the vehicle's driving speed value, wherein the second preset table includes a correspondence between the vehicle's driving speed value and the smooth braking torque value. The smooth braking torque value corresponding to the vehicle at different driving speeds can be determined in advance based on experiments and experience. The setting principle of the smooth braking torque value in the second preset table is that the smooth braking torque value corresponding to each driving speed value is less than the maximum braking torque value corresponding to the driving speed value.

[0089] Step S304: controlling the electric brake system of the vehicle to output the required braking torque according to the braking torque value.

[0090] This step can refer to step S103, and will not be described in detail in this embodiment of the present application.

[0091] Step S305: when it is determined according to the pedaling parameter that the preset emergency braking condition is met, the driving speed value of the vehicle is obtained.

[0092] Optionally, step S305 may include:

[0093] Sub-step S3051, when the pedaling depth value is greater than the preset depth threshold and the continuous pedaling time exceeds the preset time, it is determined that the preset emergency braking condition is met, or, when the pedaling pressure value is greater than the preset pressure threshold and the continuous pedaling time exceeds the preset time, it is determined that the preset emergency braking condition is met.

[0094] Since the brake pedal does not have the power assist function after the vehicle's brake assist system fails, the brake pedal is difficult to be stepped on, and the driver needs more force to step on the brake pedal. Therefore, when the driver steps on the brake pedal with all his strength, the brake pedal cannot be stepped on to the maximum stroke. Therefore, when calibrating the brake pedal stroke and the braking torque value, the maximum braking torque value cannot be corresponded only when the brake pedal reaches the maximum stroke. It is necessary to make the power motor output the braking torque according to the maximum braking torque value when the brake pedal's stepping depth does not reach the maximum depth. In other words, if it is detected that the driver steps on the brake deeply or heavily for a long time, it means that the driver has the intention of emergency braking.

[0095] Therefore, when the pedaling parameters include the pedaling depth, a preset depth threshold and a preset duration can be set. When the pedaling depth value is greater than the preset depth threshold and the continuous pedaling duration exceeds the preset duration, it is determined that the preset emergency braking condition is met and the vehicle needs to be emergency braked. When the pedaling parameters include the pedaling pressure, a preset pressure threshold and a preset duration can be set. When the pedaling pressure value is greater than the preset pressure threshold and the continuous pedaling duration exceeds the preset duration, it is determined that the preset emergency braking condition is met and the vehicle needs to be emergency braked.

[0096] Among them, the preset duration can be set according to actual needs. For example, the preset duration can be set to 1 second. The embodiment of the present application does not specifically limit the preset pedaling duration.

[0097] Step S306, determining a maximum braking torque corresponding to the driving speed value from a first preset table, and controlling the electric braking system of the vehicle to output the maximum braking torque to perform an emergency parking operation.

[0098] Emergency braking means that the vehicle's drive motor needs to output the maximum braking torque value. Therefore, the vehicle's current driving speed value can be obtained, and the maximum braking torque value corresponding to the driving speed value can be determined from the first preset table based on the driving speed value, and the vehicle's electric braking system can be controlled to output the maximum braking torque value to stop the vehicle as soon as possible.

[0099] Step S307, when the power battery of the vehicle is in a chargeable state, control the drive motor to enter a power generation state, and determine the power generation power of the drive motor according to the required braking torque, and the electric braking system includes the drive motor.

[0100] Among them, the electric brake system may include a drive motor, which can generate a torque in the opposite direction of the drive motor's rotation by consuming the power in the power battery, thereby generating a braking torque. For example, when the vehicle is moving forward, since the drive motor is connected to the wheels through a transmission system, the drive motor rotates forward under the drive of the wheels. At this time, by applying voltage and current to the drive motor, the drive motor can generate a braking torque in the opposite direction of rotation equal to the braking torque value. The braking torque acts on the wheels through the vehicle's transmission system, thereby increasing the vehicle's braking performance and thereby causing the vehicle to decelerate faster.

[0101] Since the vehicle's drive motor generally includes a driving condition and a power generation condition, under the driving condition, the drive motor can convert the battery's electrical energy into the vehicle's kinetic energy, and under the power generation condition, the drive motor can also convert the vehicle's kinetic energy into electrical energy.

[0102] The domain controller can obtain the feedback signal of the battery management system, which can indicate whether the current power battery is in a chargeable state.

[0103] After determining that the power battery is in a rechargeable state, the domain controller can calculate the power generation of the drive motor when outputting the braking torque value based on the size of the braking torque value.

[0104] Step S308: controlling the driving motor to generate electric energy with the generated power, and charging the electric energy into the power battery.

[0105] After calculating the power generation corresponding to the braking torque value, the drive motor is controlled to generate power with the power generation, so that the drive motor converts the kinetic energy of the vehicle into electrical energy, thereby generating a braking torque corresponding to the braking torque value. At the same time, the electrical energy generated by the drive motor is charged into the drive battery.

[0106] Step S309, when the power battery is in a non-rechargeable state and the temperature of the power battery is lower than a preset temperature threshold, control the drive motor to enter a power generation state, and determine the power generation power of the drive motor according to the required braking torque, and the electric braking system includes the drive motor.

[0107] After determining that the power battery is in a non-rechargeable state, the domain controller can obtain the temperature value of the power battery and determine whether the battery temperature is lower than a preset temperature threshold. When the battery temperature is lower than the preset temperature threshold, the drive motor is controlled to enter the power generation condition, and based on the braking torque value, the power generation power of the drive motor when the braking torque value is output is calculated.

[0108] Step S310, controlling the drive motor to generate electric energy with the generated power, and controlling the electric energy to flow through the resistance of the power battery to heat the electric battery until the temperature of the power battery reaches the preset temperature threshold.

[0109] After calculating the power generation corresponding to the braking torque value, the drive motor is controlled to generate power with the power generation, so that the drive motor converts the kinetic energy of the vehicle into electrical energy, and then the drive motor generates a braking torque corresponding to the braking torque value. At the same time, the electrical energy generated by the drive motor is introduced into the heating unit of the power battery, so that the electrical energy generated by the drive motor flows through the resistor near the power battery to heat the power battery. Among them, the preset temperature threshold can be the optimal operating temperature value of the power battery. The kinetic energy of the vehicle can be converted into thermal energy, so that the temperature of the power battery increases, thereby improving the performance of the power battery.

[0110] The temperature of the power battery is continuously monitored, and when the temperature of the power battery reaches a preset temperature threshold, the drive motor is controlled to stop generating electricity and instead enter a drive mode that consumes electricity to generate braking torque to continue providing braking torque.

[0111] In summary, an embodiment of the present invention provides a vehicle control method, including: when it is determined that a mechanical brake system of the vehicle fails, obtaining the pedaling parameters of the brake pedal of the vehicle; determining the braking torque value according to the pedaling parameters; and controlling the electric brake system of the vehicle to output the required braking torque according to the braking torque value. In an embodiment of the present invention, after a failure occurs in the brake boosting system of the vehicle, the pedaling parameters of the brake pedal of the vehicle can be collected by a domain controller, and a suitable braking torque value can be determined according to the pedaling parameters, so that the power motor of the vehicle outputs the braking torque according to the braking torque value. Therefore, after a failure occurs in the brake boosting system of the vehicle, the power motor can assist the vehicle in deceleration, thereby improving the braking performance of the vehicle, strengthening the driver's ability to control the vehicle after the brake boosting fails, and reducing the probability of traffic accidents.

[0112] refer to Figure 4 , shows a structural block diagram of a vehicle control device according to an embodiment of the present invention:

[0113] The acquisition module 401 is used to acquire the stepping parameters of the brake pedal of the vehicle when it is determined that the mechanical brake system of the vehicle fails.

[0114] The torque module 402 is used to determine a braking torque value according to the pedaling parameter.

[0115] The braking module 403 is used to control the electric braking system of the vehicle to output the required braking torque according to the braking torque value.

[0116] Optionally, the controller may further include:

[0117] The determination module is used to determine whether the pedaling parameters are valid.

[0118] Optionally, the determination module may include:

[0119] The status bit submodule is used to obtain the status bit information corresponding to the pedaling parameter.

[0120] The judging submodule is used to judge whether the state bit information is the same as the first preset value.

[0121] The valid submodule is used to determine that the pedaling parameter is valid when the status bit information is the same as the first preset value.

[0122] The invalid submodule is used to determine that the pedaling parameter is invalid when the status bit information is different from the first preset value.

[0123] Optionally, the torque module may also include:

[0124] The parameter effective torque submodule is used to determine the braking torque value according to the pedaling depth value of the brake pedal, wherein the pedaling depth value and the braking torque value have a linear corresponding relationship, or to determine the braking torque value according to the pedaling pressure value of the brake pedal, wherein the pedaling pressure value and the braking torque value have a linear corresponding relationship.

[0125] The switch information submodule is used to obtain the switch information of the brake switch of the vehicle.

[0126] The emergency parking submodule is used to perform an emergency parking operation according to a first preset parking strategy when it is determined according to the switch information that the brake switch is triggered.

[0127] The smooth parking submodule is used to perform a smooth parking operation according to a second preset parking strategy when it is determined according to the switch information that the brake switch is not triggered.

[0128] Optionally, the emergency stop submodule can also be used to obtain the driving speed value of the vehicle; determine the maximum braking torque corresponding to the driving speed value from a first preset table, and control the electric braking system of the vehicle to output the maximum braking torque to perform an emergency stop operation.

[0129] Optionally, the smooth parking submodule can also be used to obtain the driving speed value of the vehicle; determine the smooth braking torque corresponding to the driving speed value from a second preset table, and control the electric braking system of the vehicle to output the smooth braking torque to perform a smooth parking operation.

[0130] Optionally, the controller may further include:

[0131] The speed acquisition module is used to acquire the driving speed value of the vehicle when it is determined that a preset emergency braking condition is met according to the pedaling parameter.

[0132] The emergency parking module is used to determine the maximum braking torque corresponding to the driving speed value from a first preset table, and control the electric braking system of the vehicle to output the maximum braking torque to perform an emergency parking operation.

[0133] Optionally, the speed acquisition module may include:

[0134] The emergency braking determination submodule is used to determine that the preset emergency braking condition is met when the pedaling depth value is greater than the preset depth threshold and the continuous pedaling time exceeds the preset time, or to determine that the preset emergency braking condition is met when the pedaling pressure value is greater than the preset pressure threshold and the continuous pedaling time exceeds the preset time.

[0135] Optionally, the controller may further include:

[0136] The first power module is used to control the drive motor to enter a power generation state when the power battery of the vehicle is in a chargeable state, and determine the power generation power of the drive motor according to the required braking torque. The electric braking system includes the drive motor.

[0137] A charging module is used to control the driving motor to generate electric energy with the generated power, and to charge the electric energy into the power battery.

[0138] The second power module is used to control the drive motor to enter the power generation condition when the power battery is in a non-rechargeable state and the temperature of the power battery is lower than a preset temperature threshold, and determine the power generation power of the drive motor according to the required braking torque. The electric braking system includes the drive motor.

[0139] The discharge module is used to control the drive motor to generate electric energy with the generated power, and control the electric energy to flow through the resistance of the power battery to heat the electric battery until the temperature of the power battery reaches the preset temperature threshold.

[0140] In summary, an embodiment of the present invention provides a vehicle control device, which can obtain the pedaling parameters of the vehicle's brake pedal when it is determined that the vehicle's mechanical brake system has failed; determine the braking torque value according to the pedaling parameters; and control the vehicle's electric brake system to output the required braking torque according to the braking torque value. In an embodiment of the present invention, after a failure occurs in the vehicle's brake boosting system, the pedaling parameters of the vehicle's brake pedal can be collected by a domain controller, and a suitable braking torque value can be determined according to the pedaling parameters, so that the vehicle's power motor can output braking torque according to the braking torque value. Therefore, after a failure occurs in the vehicle's brake boosting system, the power motor can assist the vehicle in deceleration, thereby improving the vehicle's braking performance, enhancing the driver's ability to control the vehicle after the brake boosting fails, and reducing the probability of traffic accidents.

[0141] An embodiment of the present invention further provides a vehicle, including a domain controller, the domain controller including a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor executes the above-mentioned vehicle control method.

[0142] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0143] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0144] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A vehicle control method, characterized in that: The method comprises: When it is determined that a mechanical brake system of the vehicle fails, obtaining a stepping parameter of a brake pedal of the vehicle; determining a braking torque value according to the pedaling parameter; Controlling the electric brake system of the vehicle to output a required braking torque according to the braking torque value; After the step of controlling the electric brake system of the vehicle to output the required braking torque according to the braking torque value, the method further includes: When it is determined according to the pedaling parameter that a preset emergency braking condition is met, obtaining a driving speed value of the vehicle; determining a maximum braking torque corresponding to the driving speed value from a first preset table, and controlling an electric braking system of the vehicle to output the maximum braking torque to perform an emergency parking operation; When the power battery of the vehicle is in a chargeable state, controlling the drive motor to enter a power generation state, and determining the power generation power of the drive motor according to the required braking torque, the electric brake system including the drive motor; Controlling the driving motor to generate electric energy with the generated power, and charging the electric energy into the power battery; After the step of obtaining the stepping parameters of the brake pedal of the vehicle, the method further includes: Determining whether the stepping parameters are valid; In the case where the pedaling parameter is invalid, the step of determining the braking torque value according to the pedaling parameter comprises: Acquiring switch information of a brake switch of the vehicle; When it is determined according to the switch information that the brake switch is triggered, an emergency parking operation is performed according to a first preset parking strategy; When it is determined according to the switch information that the brake switch is not triggered, performing a smooth parking operation according to a second preset parking strategy; The step of performing an emergency parking operation according to the first preset parking strategy includes: Obtaining a driving speed value of the vehicle; determining a maximum braking torque corresponding to the driving speed value from a first preset table, and controlling an electric braking system of the vehicle to output the maximum braking torque to perform an emergency parking operation; The step of performing a smooth parking operation according to the second preset parking strategy includes: Obtaining a driving speed value of the vehicle; A smooth braking torque corresponding to the driving speed value is determined from a second preset table, and an electric brake system of the vehicle is controlled to output the smooth braking torque to perform a smooth parking operation.

2. The method according to claim 1, characterized in that The step of judging whether the pedaling parameter is valid comprises: Obtaining status bit information corresponding to the stepping parameter; Determining whether the status bit information is the same as a first preset value; When the state bit information is the same as the first preset value, it is determined that the stepping parameter is valid; When the status bit information is different from the first preset value, it is determined that the pedaling parameter is invalid.

3. The method according to claim 1, characterized in that: In the case where the pedaling parameter is valid, the step of determining the braking torque value according to the pedaling parameter comprises: The braking torque value is determined according to the pedaling depth value of the brake pedal, wherein the pedaling depth value and the braking torque value have a linear corresponding relationship, Alternatively, the braking torque value is determined according to the pedal pressure value of the brake pedal, wherein the pedal pressure value and the braking torque value have a linear corresponding relationship.

4. The method according to claim 1, characterized in that: The step of determining, according to the pedaling parameter, that a preset emergency braking condition is satisfied comprises: When the pedaling depth value is greater than the preset depth threshold and the continuous pedaling time exceeds the preset time, it is determined that the preset emergency braking condition is met, or, When the pedaling pressure value is greater than a preset pressure threshold and the continuous pedaling time exceeds a preset time, it is determined that the preset emergency braking condition is met.

5. The method according to claim 1, characterized in that After the step of controlling the electric brake system of the vehicle to output the required braking torque according to the braking torque value, the method further includes: When the power battery is in a non-rechargeable state and the temperature of the power battery is lower than a preset temperature threshold, the drive motor is controlled to enter a power generation state, and the power generation power of the drive motor is determined according to the required braking torque, wherein the electric brake system includes the drive motor; The drive motor is controlled to generate electric energy with the generated power, and the electric energy is controlled to flow through the resistance of the power battery to heat the electric battery until the temperature of the power battery reaches the preset temperature threshold.

6. A domain controller, characterized in that: The domain controller comprises: An acquisition module, used for acquiring a stepping parameter of a brake pedal of the vehicle when it is determined that a mechanical brake system of the vehicle fails; A torque module, used for determining a braking torque value according to the pedaling parameter; A braking module, used for controlling the electric braking system of the vehicle to output a required braking torque according to the braking torque value; After the step of controlling the electric brake system of the vehicle to output the required braking torque according to the braking torque value, the method further includes: When it is determined according to the pedaling parameter that a preset emergency braking condition is met, obtaining a driving speed value of the vehicle; determining a maximum braking torque corresponding to the driving speed value from a first preset table, and controlling an electric braking system of the vehicle to output the maximum braking torque to perform an emergency parking operation; When the power battery of the vehicle is in a chargeable state, controlling the drive motor to enter a power generation state, and determining the power generation power of the drive motor according to the required braking torque, the electric brake system including the drive motor; Controlling the driving motor to generate electric energy with the generated power, and charging the electric energy into the power battery; After the step of obtaining the stepping parameters of the brake pedal of the vehicle, the method further includes: Determining whether the stepping parameters are valid; In the case where the pedaling parameter is invalid, the step of determining the braking torque value according to the pedaling parameter comprises: Acquiring switch information of a brake switch of the vehicle; When it is determined according to the switch information that the brake switch is triggered, an emergency parking operation is performed according to a first preset parking strategy; When it is determined according to the switch information that the brake switch is not triggered, performing a smooth parking operation according to a second preset parking strategy; The step of performing an emergency parking operation according to the first preset parking strategy includes: Obtaining a driving speed value of the vehicle; determining a maximum braking torque corresponding to the driving speed value from a first preset table, and controlling an electric braking system of the vehicle to output the maximum braking torque to perform an emergency parking operation; The step of performing a smooth parking operation according to the second preset parking strategy includes: Obtaining a driving speed value of the vehicle; A smooth braking torque corresponding to the driving speed value is determined from a second preset table, and an electric brake system of the vehicle is controlled to output the smooth braking torque to perform a smooth parking operation.

7. A vehicle, characterized in that: It comprises a domain controller as claimed in claim 6.

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