Brake control method, device and system and vehicle

Abstract

The invention discloses a brake control method, device and system and a vehicle, relates to the technical field of vehicle control, and is used for realizing a relatively large brake deceleration effect after a main hydraulic brake system fails. The method comprises the steps that according to a braking request, if it is determined that a hydraulic braking system of the vehicle fails and the energy recycling capacity of a battery pack limits the motor recycling strength, a first motor of the vehicle is controlled to brake, a second motor of the vehicle is controlled to drive, and wheels corresponding to the second motor are braked through an EPB system. By the adoption of the braking control method, large deceleration can be achieved through braking of the first motor and EPB braking of the wheels corresponding to the second motor, redundant electric energy generated by braking of the first motor can be consumed through driving of the second motor, and under the condition that the actual allowable charging capacity of the battery pack is not exceeded, the braking speed of the battery pack is increased. The recovery deceleration of the whole vehicle is fully utilized, and the effective braking deceleration effect is achieved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a braking control method, device, system and vehicle. Background Art

[0002] With the development of automotive technology, people's demand for vehicle intelligence is increasing. As a key subsystem of the vehicle chassis system, the automotive braking system can be used to change the vehicle's driving speed. Its performance directly affects the vehicle's driving performance, braking stability, driving comfort, and driving safety. It has become one of the basic configurations of the vehicle.

[0003] Currently, automotive braking systems can be implemented using a primary hydraulic braking system. However, if the primary hydraulic braking system fails, the vehicle still needs to have significant deceleration capability. For vehicles without redundant hydraulic braking systems or auxiliary hydraulic braking systems, auxiliary braking can be achieved through electromechanical regenerative braking or an electric parking brake (EPB). However, the EPB is located on the rear axle of the vehicle. When high deceleration is required, the rear wheel braking force will exceed the road adhesion limit, preventing significant deceleration. While electromechanical regenerative braking can provide a certain degree of deceleration, its deceleration capacity is limited when the battery pack is fully charged or the recharging effect is poor at low temperatures. Forcing recharging can cause the battery pack to overcharge. Short-term overcharging can cause battery pack failure and degradation, while prolonged overcharging can cause lithium deposition within the battery pack, affecting battery performance.

[0004] In summary, further research is needed on how to achieve a greater braking and deceleration effect after the main hydraulic brake system fails. Summary of the Invention

[0005] The present application provides a braking control method, device, system and vehicle, which are used to achieve a large braking and deceleration effect after the main hydraulic braking system fails.

[0006] In a first aspect, the present application provides a braking control method applicable to a vehicle, the vehicle comprising a first motor and a second motor; the method comprising: receiving a braking request, and determining, based on the braking request, that the hydraulic braking system of the vehicle has failed, and that the energy recovery capability of the vehicle's battery pack limits the motor recovery intensity, then controlling the braking of the first motor, controlling the driving of the second motor, and braking the wheels corresponding to the second motor through the EPB system.

[0007] Using the above braking control method, if the battery pack's recharge capacity is limited when the main hydraulic service brake fails, to maximize the vehicle's recharge deceleration, one motor is used for braking, while the other motor is used to apply the parking brake. The kinetic energy required to drive the other motor comes from the braking of the first motor. This way, the kinetic energy generated by the first motor's braking does not need to be fully recovered to charge the battery pack. Even if the battery pack's recharge capacity is limited due to factors such as a fully charged battery pack or poor recharge performance at low temperatures, the combination of braking with one motor and EPB braking with the other motor ensures that the vehicle still has a high deceleration rate, regardless of the battery pack's recharge capacity, thereby achieving effective braking and deceleration.

[0008] In a possible design, the vehicle further includes a first shaft and a second shaft, the first motor is disposed on the first shaft, and the second motor is disposed on the second shaft.

[0009] Based on the above design, the braking motor and the driving motor can be placed on different axes. In this way, even if the ground adhesion coefficient is limited, one axis motor can be used to brake the other axis motor to drive, thereby achieving a larger braking deceleration and preventing the wheels from locking.

[0010] Alternatively, if the vehicle is a two-axle vehicle, the first axle is the front axle and the second axle is the rear axle, or the first axle is the rear axle and the second axle is the front axle.

[0011] In one possible design, the first axle is the front axle and the second axle is the rear axle.

[0012] Based on the above design, the front axle motor can be controlled to brake, the rear axle motor can be driven, and the rear axle wheels can be superimposed with EPB braking to provide better stability.

[0013] In one possible design, the first motor braking and the second motor driving may have the following association relationship:

[0014] In the first relationship, all the electric energy generated by the first motor's braking is used to drive the second motor. Under this relationship, the electric energy generated by the first motor's braking will not be recharged back into the battery pack. This method is particularly suitable for scenarios where the battery pack is fully charged or cannot be charged due to factors such as low temperature. It can provide greater deceleration without being limited by the problem of the battery pack being unable to charge.

[0015] Relationship 2: A portion of the braking energy generated by the first motor is recharged back into the battery pack, while the remaining portion is used to drive the second motor. Under this relationship, a portion of the braking energy generated by the first motor is recharged back into the battery pack. The specific amount of recharge can be designed based on actual scenario requirements, pre-configured, or customized to increase the flexibility of braking control. Since some energy is recharged back into the battery pack, energy utilization can be improved, thereby enhancing the vehicle's range.

[0016] In one example of the second relationship above, the energy recharged to the battery pack is exactly equal to the battery pack's actual maximum allowable charge energy. In other words, the maximum energy the battery pack can receive is recharged back to the battery pack, and the remaining energy is used to drive the second motor. This maximizes the use of reclaimed energy to improve vehicle range while also minimizing the driving force of the second motor, making braking easier or more beneficial for the EPB system.

[0017] In a possible design, the first motor is controlled to brake, and the second motor is controlled to drive. Specifically, all motors on the shaft where the first motor is located are controlled to brake, and all motors on the shaft where the second motor is located are controlled to drive.

[0018] Based on the above design, all motors on each axis can be in the same state, improving the stability of braking or driving of each axis, thereby improving the stability of vehicle driving.

[0019] In one possible design, after determining that the vehicle's hydraulic brake system has failed, the target deceleration of the vehicle can be determined based on the braking request, and then one of the following four branches can be executed to perform vehicle braking:

[0020] Branch 1: If the desired charging power corresponding to the target deceleration is less than or equal to the actual maximum allowable charging power of the battery pack, the first motor and / or the second motor are controlled to brake, and the electrical energy generated by the braking of the first motor and / or the second motor is recharged back into the battery pack. Based on branch 1, when the braking request can be responded to by purely electric motor regenerative braking, the target deceleration is provided by using one or both electric motors for regenerative braking, which can meet the vehicle's braking requirements while reducing the difficulty of braking.

[0021] Branch 2: If the target deceleration is less than or equal to the maximum braking deceleration of the EPB system, the EPB system is used to brake the wheels corresponding to the second motor. Based on branch 2, when the braking request can be responded to by pure EPB dynamic braking, the pure EPB system is used to brake the wheels corresponding to the second motor to provide the target deceleration, which can meet the vehicle's braking requirements while reducing braking difficulty;

[0022] Branch three: If the target deceleration is greater than the EPB system's maximum braking deceleration, but the vehicle's battery pack energy recovery capability does not limit the motor regeneration intensity, the first motor and / or the second motor are controlled for braking, and the wheels corresponding to the second motor are braked via the EPB system. Based on branch three, when a braking request cannot be responded to by pure EPB dynamic braking or pure motor regeneration braking, a combination of motor regeneration braking and EPB dynamic braking can be used to provide a relatively large deceleration. The braking motor can be either only one or both motors, depending on the intensity of the braking request, to improve braking flexibility and reduce energy waste caused by braking operations.

[0023] Branch 4: If the target deceleration is greater than the EPB system's maximum braking deceleration and the vehicle's battery pack's energy recovery capacity limits the motor's regenerative capacity, the first motor is controlled to brake, the second motor is controlled to drive, and the wheels corresponding to the second motor are braked via the EPB system. Based on branch 4, when a braking request cannot be responded to by pure EPB dynamic braking or pure motor regenerative braking, and the battery regenerative capacity is limited but the vehicle requires emergency braking, the first motor is controlled to brake and the second motor is driven to superimpose EPB dynamic braking on the wheels. This achieves both a relatively large deceleration and a good braking effect through the braking of the first motor and EPB dynamic braking of the wheels corresponding to the second motor, while also consuming excess electrical energy generated by the braking of the first motor through the drive of the second motor. This fully utilizes the vehicle's regenerative deceleration within the battery pack's actual allowable recharge capacity, ensuring the vehicle can achieve a large deceleration.

[0024] In an example of the above design, whether the vehicle's battery pack energy recovery capability limits the motor recovery intensity can be determined in the following manner: first, the motor recovery deceleration is determined based on the target deceleration and the maximum braking deceleration of the EPB system. Then, it is determined whether the expected charging power corresponding to the motor recovery deceleration is greater than the actual allowed maximum charging power of the battery pack. If so, it is determined that the vehicle's battery pack energy recovery capability limits the motor recovery intensity. If not, it is determined that the vehicle's battery pack energy recovery capability does not limit the motor recovery intensity.

[0025] Based on the above example, the actual maximum allowable charging power of the battery pack can be used as a threshold to determine whether the energy recovery capability of the battery pack exceeds the motor recovery intensity. The actual maximum allowable charging power of the battery pack can be obtained from the battery management system. The information is easy to obtain, and the judgment steps are simple to execute, requiring less time, which can reduce the control delay of the braking control method.

[0026] In one possible design, the failure of the vehicle's hydraulic braking system is determined based on a braking request. Specifically, based on the braking request, a braking command is issued to the hydraulic braking system. If fault information of the hydraulic braking system is received, and / or the vehicle does not start braking within the first time period of issuing the braking command, it is determined that the vehicle's hydraulic braking system has failed.

[0027] Based on the above design, the hydraulic brake system can be monitored in real time to see if it fails, either by actively receiving fault information or actively monitoring the vehicle's braking condition. Failure monitoring is more flexible, has higher monitoring accuracy, and is less difficult to operate.

[0028] In a possible design, if it is determined based on the braking request that the hydraulic braking system has not failed, the wheels corresponding to the first motor and the wheels corresponding to the second motor are hydraulically braked by the hydraulic braking system.

[0029] Based on the above design, the hydraulic braking system can be used for braking when the hydraulic braking system has not failed. As the main braking system of the vehicle, the hydraulic braking system has great advantages in braking accuracy, braking efficiency and operating difficulty compared to EPB dynamic braking and motor recovery braking.

[0030] In one possible design, the braking request may include at least one of the following: a request generated by a user pressing the brake pedal, an automatic parking request, an adaptive cruise request, and an automatic emergency braking request.

[0031] Based on the above design, the braking control method provided in this application can be enabled in a variety of scenarios, so that the braking control method can be applicable to various driving scenarios and various typical working conditions, with good universality and versatility.

[0032] In the second aspect, the present application provides a braking control device, which has the function of implementing the method of the above-mentioned first aspect or any one of the designs in the first aspect. For example, the braking control device includes a module, unit or means for executing the operations involved in the method of the above-mentioned first aspect or any one of the designs or examples in the first aspect. The module, unit or means can be implemented by software, or by hardware, or by a combination of software and hardware.

[0033] In a third aspect, the present application provides a brake control device comprising an interface circuit and one or more processors. The one or more processors are coupled to a memory. The memory is used to store part or all of the computer programs or instructions necessary to implement the functions described in the first aspect or any of the designs or examples of the first aspect. The one or more processors are capable of executing the computer programs or instructions. When executed, the computer programs or instructions cause the brake control device to implement the method described in the first aspect or any of the designs or examples of the first aspect. The interface circuit is used to implement communication functions within the brake control device and / or communication functions between the brake control device and other devices or components.

[0034] In one possible design, the communication interface may be a transceiver, or an input / output interface. Alternatively, the transceiver may be a transceiver circuit. Alternatively, the input / output interface may be an input / output circuit.

[0035] In another possible design, when the brake control device is a chip or a chip system, the communication interface can be an input / output interface, interface circuit, output circuit, input circuit, pin or related circuit on the chip or chip system. The processor can also be embodied as a processing circuit or a logic circuit.

[0036] The above braking control device can be a controller in the aforementioned vehicle, or a module in the controller (such as a processor, chip or chip system), or a logical node, logic module or software that can realize all or part of the controller functions.

[0037] In a fourth aspect, the present application provides a braking control system, which includes a braking control device, which may be the braking control device in the above-mentioned second aspect or any one of the designs, or may be the braking control device in the above-mentioned third aspect or any one of the designs, and the braking control device may execute the method in the above-mentioned first aspect or any one of the designs of the first aspect.

[0038] In one possible design, the braking control system may also include a hydraulic braking system connected to a braking control device, which is used to control the hydraulic braking system to perform hydraulic braking on the first motor and the second motor of the vehicle when the hydraulic braking system has not failed.

[0039] In one possible design, the braking control system may also include a parking brake system, which is connected to a braking control device. The braking control device is also used to control the parking brake system to brake the first motor and / or second motor of the vehicle when the hydraulic braking system fails but the parking brake system does not fail.

[0040] In one possible design, the braking control system may also include N motors, where N is an integer greater than or equal to 2. The N motors are connected to a braking control device, which is also used to control the braking of one or more of the N motors when the hydraulic braking system fails but the energy recovery capability of the battery pack is not 0.

[0041] In an example of the above design, the brake control device may include a main controller and a first controller, the first controller is connected to the hydraulic brake system, and the main controller is respectively connected to the first controller, the electronic parking brake system, and the vehicle's motor. The main controller is used to execute the method as described in the first aspect or any one of the designs or examples of the first aspect above, and send a braking instruction to one or more of the first controller, the electronic parking brake system, and the vehicle's motor. The first controller is used to control the hydraulic brake system to hydraulically brake the vehicle's motor according to the braking instruction. The electronic parking brake system is used to brake the vehicle's wheels according to the braking instruction. The vehicle's motor is used to brake or drive the vehicle's wheels according to the braking instruction.

[0042] In a further example, the braking control device may also include a second controller, which is connected between the main controller and the electronic parking brake system. The main controller is also used to send a braking instruction to the second controller, and the second controller is used to control the electronic parking brake system to brake the vehicle's wheels according to the braking instruction.

[0043] In a further example, the braking control device may also include a third controller, which is connected between the main controller and the vehicle's motor. The main controller is also used to send braking instructions to the third controller, and the third controller is used to control the vehicle's motor braking or driving according to the braking instructions.

[0044] In a fifth aspect, the present application provides a vehicle comprising a braking control device as in the second aspect or any one of the designs of the second aspect, or comprising a braking control device as in the third aspect or any one of the designs of the third aspect, or comprising a braking control system as in the fourth aspect or any one of the designs of the fourth aspect.

[0045] In a sixth aspect, the present application provides a computer-readable storage medium, which stores computer-readable instructions. When a computer reads and executes the computer-readable instructions, the computer executes the method in the above-mentioned first aspect or any one of the designs of the first aspect.

[0046] In a seventh aspect, the present application provides a computer program product. When a computer reads and executes the computer program product, the computer executes the method in the above-mentioned first aspect or any one of the designs of the first aspect.

[0047] In an eighth aspect, the present application provides a chip for reading a computer program stored in a memory and executing the method of the first aspect or any one of the designs of the first aspect. Optionally, the chip may include a processor, which is coupled to the memory and is used to read the computer program stored in the memory and implement the method of the first aspect or any one of the designs of the first aspect. Optionally, the chip may also include components such as a memory, a communication interface, and a power supply module. The memory is used to store computer programs; the communication interface is used to receive and send data; and the power supply module is used to power the processor.

[0048] In a ninth aspect, the present application provides a chip system, comprising a processor for supporting a computer in implementing the method of the first aspect or any one of the designs of the first aspect. In one possible design, the chip system further comprises a memory for storing the necessary programs and data for the computer. The chip system may be composed of a chip or may include a chip and other discrete devices.

[0049] The technical effects that can be achieved in the above-mentioned second to ninth aspects can be referred to the description of the beneficial effects in the above-mentioned first aspect, and will not be repeated here one by one. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1a A schematic diagram illustrating a possible application scenario provided by this application is shown as an example;

[0051] Figure 1b A schematic diagram exemplarily illustrates another possible application scenario provided by the present application;

[0052] Figure 2a A schematic diagram illustrating an architecture of a braking control system provided by the present application is exemplified;

[0053] Figure 2b A schematic diagram illustrating an architecture of another braking control system provided by the present application is exemplified;

[0054] Figure 2c A schematic diagram illustrating an architecture of another braking control system provided by the present application is exemplified;

[0055] Figure 2d A schematic diagram illustrating an exemplary architecture of another braking control system provided by the present application;

[0056] Figure 3 A schematic diagram showing the connection relationship between a motor and a wheel provided in the present application is exemplified;

[0057] Figure 4 A schematic diagram exemplarily illustrates a flow chart of a braking control method provided by the present application;

[0058] Figure 5A schematic diagram illustrating a specific implementation flow of a braking control method provided by the present application is shown as an example;

[0059] Figure 6 A schematic diagram of a specific braking control method provided by the present application is exemplified;

[0060] Figure 7 An overall flow chart of a braking control method provided by the present application is exemplified;

[0061] Figure 8 The following is a schematic diagram showing the structure of a brake control device provided by the present application;

[0062] Figure 9 The following is a schematic diagram showing the structure of another brake control device provided by the present application;

[0063] Figure 10 The following is an exemplary diagram showing the architecture of another braking control system provided by the present application. DETAILED DESCRIPTION

[0064] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0065] The following is an explanation of some of the terms used in this application. It should be noted that these explanations are for the purpose of facilitating understanding by those skilled in the art and do not limit the scope of protection claimed in this application.

[0066] 1. Intelligent Driving Level

[0067] Intelligent driving levels are divided into 6 levels from L0 to L5 according to the degree of automation. These 6 levels are further divided into two categories, one is L0 to L2, and the other is L3 to L6.

[0068] At levels L0 to L2, the driver is primarily responsible for dynamic driving tasks, with the intelligent driving system providing only auxiliary functions such as lane keeping and adaptive cruise control. At levels L3 to L5, the need for driver intervention is reduced, with the intelligent driving system able to autonomously complete all driving tasks under specific conditions.

[0069] 2. Intelligent Driving Downgrade

[0070] Intelligent driving degradation usually refers to fault degradation. This is a safety measure taken when an intelligent driving system malfunctions or anomalies occur. It aims to ensure that the vehicle's basic control and safety performance are not affected, and to maintain a certain level of control and safety even if the intelligent driving system is not fully functioning.

[0071] For example, if an autonomous vehicle encounters a software anomaly or hardware failure, the intelligent driving system may restrict the vehicle's lane-changing function, limit its speed, or even enter an emergency stop. These measures allow the driver ample time to take over the vehicle and alert surrounding traffic participants, effectively preventing traffic accidents.

[0072] The previous text introduced some of the terms involved in this application. The following text introduces the possible application scenarios of this application.

[0073] See also Figure 1a and Figure 1b , which exemplifies two possible application scenarios provided by this application.

[0074] Figure 1a and Figure 1b The scenario shown takes the braking control method applied to a vehicle as an example. When the vehicle enters an emergency braking scenario, such as Figure 1a The narrow road U-turn scenario shown, or Figure 1b In the off-road obstacle scene shown, as well as other scenarios, such as emergencies such as fire or traffic accidents on the road ahead, encountering slippery roads caused by sudden weather changes, sudden tire blowouts, etc., requiring an emergency lane change to the emergency lane but the vehicle ahead is too close, the driver encountering a sudden illness or other emergency, and emergency parking, if the recovery capacity of the vehicle's battery pack is insufficient, the vehicle can control one of the vehicle's motors to brake according to the braking control method provided in this application, and simultaneously superimpose the parking brake on the other motor to fully utilize the maximum recovery capacity of the motor, ensure that the vehicle slows down or even stops at a larger deceleration, and improve braking performance and driving safety. Conversely, if the recovery capacity of the vehicle's battery pack is sufficient, the vehicle can control the vehicle's braking according to the original control logic, such as controlling the braking of the vehicle's two motors, and recharging all the kinetic energy generated by the braking of the two motors to the battery pack to improve the vehicle's endurance.

[0075] The above vehicles can be of any type, including but not limited to pure electric vehicles (pure EV / battery EV), hybrid electric vehicles (HEV), range-extended electric vehicles (REEV), plug-in hybrid electric vehicles (PHEV), other new energy vehicles (NEV), or fuel-powered vehicles. These vehicles can be used in areas such as intelligent driving, assisted driving, and connected vehicles.

[0076] It should be understood that the above application scenarios are only examples, and the braking control method provided in this application can also be applied to other possible scenarios, not limited to the scenarios exemplified above. For example, the braking control method can also be applied to other means of transportation, such as ships, airplanes, drones, trains, subways, high-speed railways or transport vehicles, to assist the driver in achieving or automatically achieving emergency braking of the vehicle. For another example, the braking control method can also be applied to robots as an auxiliary braking force for the robot's travel to achieve the flexibility of the robot's emergency braking. The robot may include but is not limited to a household robot, a navigation robot, an autonomous food delivery robot, a medical robot or an industrial robot. For another example, the braking control method can also be applied to smart life scenarios, such as being integrated into an automatic following trolley case, or integrated into a smart dining chair, or integrated into a smart means of transportation, etc. They will not be listed one by one here.

[0077] It should be noted that the application scenarios described in this application are intended to more clearly illustrate the technical solutions of this application and do not constitute a limitation on the technical solutions provided in this application.

[0078] As described in the background art, in the prior art, when the main hydraulic brake system fails, pure motor regenerative braking or pure EPB dynamic braking can be used to assist vehicle braking, but both braking methods cannot achieve a large vehicle deceleration.

[0079] In response to this, relevant solutions consider combining the two braking methods of motor regenerative braking and EPB dynamic braking. Motor regenerative braking is used to control the braking of the front and rear axle motors of the vehicle together, while the EPB system is used to perform parking brakes on the rear axle wheels. However, this solution can only achieve the expected large deceleration effect when the battery pack has sufficient recharging capacity. If the battery pack has insufficient recharging capacity, such as when the battery pack is fully charged or the recharging effect is poor at low temperatures, the electric energy generated by the braking of the front and rear axle motors together far exceeds the electric energy that the battery pack can receive. In this case, forced recharging will cause problems such as battery pack failure or battery performance degradation as described in the background technology, while not forcing recharging will not provide a large deceleration effect because the battery pack has no recharging capacity or has limited recharging capacity.

[0080] In light of this, the present application provides a braking control method that, when the battery pack's recharge capacity is insufficient, controls the braking of the vehicle's first motor and uses some or all of the kinetic energy generated by the first motor's braking to drive the second motor. Meanwhile, EPB dynamic braking is superimposed on the wheels corresponding to the second motor. This method not only achieves a significant deceleration by combining the regenerative braking of the first motor and the EPB dynamic braking of the wheels corresponding to the second motor, but also uses some or all of the regenerative braking of the first motor that exceeds the battery pack's recharge capacity to drive the second motor. This method fully utilizes the vehicle's maximum regenerative braking capacity to achieve the desired significant deceleration without exceeding the battery pack's recharge capacity, making it suitable for emergency braking and similar braking scenarios.

[0081] The braking control method in the present application can be applied to a braking control system, which can be integrated into a vehicle, which can be a vehicle with two or more motors, such as a car.

[0082] For example, if the means of transport is a vehicle, please refer to Figure 2a , which exemplarily shows a schematic diagram of the architecture of a brake control system provided by the present application. In this architecture, the brake control system 200 may include a main controller 210, a first controller 221, a second controller 222, and a third controller 223. Optionally, it may also include a hydraulic brake system 231, a parking brake system 232, and an electric drive force device, such as at least two motors 2331 to 233N, where N is an integer greater than or equal to 2. The main controller 210 is coupled to the first controller 221, the second controller 222, and the third controller 223 respectively. The first controller 221 is coupled to the hydraulic brake system 231, the second controller 222 is coupled to the parking brake system 232, and the third controller 223 is coupled to at least two motors 2331 to 233N.

[0083] In some examples, the main controller 210 and the first to third controllers 221 to 223 are coupled via a bus, such as a controller area network (CAN) bus. The main controller 210 and the first to third controllers 221 to 223 send signals to the CAN bus, and the opposite device receives and responds to the signals on the CAN bus to complete the corresponding vehicle control operation.

[0084] In order to facilitate the introduction of the specific braking control method, each component in the braking control system 200 is described in detail below.

[0085] The main controller 210 can be a device specifically used to implement the braking control function, or it can be a device that implements the braking control function while also implementing other functions. For example, in one example, the main controller 210 can be a control unit in the vehicle, such as a vehicle control unit (VCU), a vehicle dynamics control (VDC) or a mobile data center (MDC), or it can also be a domain controller, such as an intelligent driving domain controller or a chassis domain controller. Using this example, the control unit that already exists in the vehicle can be used to implement the braking control function, thereby improving the utilization rate of the in-vehicle devices.

[0086] Alternatively, in another example, to reduce the workload of the control unit in the vehicle, the main controller 210 can also be an additional control unit specifically for steering, such as a separate digital signal processing (DSP) chip. The DSP chip is equipped with all devices that can complete digital signal processing capabilities, including but not limited to: a power amplifier, an analog-to-digital converter (DAC), a digital-to-analog converter (ADC), a processing unit, etc. The DSP chip is independent of the vehicle and can achieve braking control of the vehicle by connecting to relevant components of the vehicle, such as the first controller 221 to the third controller 223, and various on-board sensors. Alternatively, in another example, the main controller 210 can also be implemented in conjunction with an independently set control unit and a control unit in the vehicle, that is, some functions of the main controller 210 are implemented by the independently set control unit, and other functions are implemented by the control unit in the vehicle. Alternatively, other examples can also be included, which are not listed here one by one.

[0087] The first controller 221, exemplarily an integrated powerbrake (IPB) control unit or an intelligent braking system (IDS), is primarily responsible for controlling the hydraulic brake system 231 to implement hydraulic braking. The principle of hydraulic braking is to transmit braking force through the pressure of hydraulic oil. When the driver depresses the brake pedal, the push rod mechanism of the integrated booster in the vehicle is displaced. The pedal travel sensor detects the displacement of the push rod mechanism and transmits the displacement signal to the first controller 221. The first controller 221 calculates the torque to be generated by the booster motor, which is then converted into braking force by the booster motor's transmission mechanism. The braking force, combined with the push rod force generated by the brake pedal through the push rod mechanism, acts on the master cylinder, where it is converted into hydraulic pressure. The hydraulically pressurized brake fluid, flowing through the brake fluid pipe, acts on the brake calipers of each axle, such as the left front wheel, left rear wheel, right front wheel, and right rear wheel, clamping the brake friction discs to achieve vehicle deceleration and braking.

[0088] Optionally, the first controller 221 can also monitor the hydraulic braking system 231. For example, it can monitor in real time whether the brake caliper clamps the brake friction disc according to the control of the first controller 221. If it is not clamped, fault information can be reported to the main controller 210 to indicate that the hydraulic braking system 231 is currently failing or malfunctioning, so that the main controller 210 can execute other braking strategies, such as calling the second controller 232 and / or the third controller 233 to perform redundant braking control.

[0089] The second controller 222, exemplarily an electronic parking brake control unit (EPB), is primarily responsible for dynamically controlling the parking brake system 232 to implement the parking function. The second controller 222 is connected to the electronic parking calipers of a particular axle 100, such as the left and right rear wheels, via a power supply line. When the driver presses the parking brake button in the vehicle, a signal indicating the pressing action is fed back to the second controller 222. The second controller 222 controls the clamping and release of the electronic parking calipers on the left and right rear wheels, adjusting the friction between the electronic parking calipers and the rear wheels to implement dynamic braking of the vehicle.

[0090] The third controller 223 can be exemplarily a motor control unit (MCU). The third controller 223 is primarily responsible for controlling the braking or driving of each motor 2331 to 233N in the vehicle. During the driving process, the driver steps on the electronic throttle, and the vehicle controller collects the opening of the electronic throttle, calculates the torque command for each motor 2331 to 233N, and sends it to the third controller 223. The third controller 223 controls the rotation of each motor 2331 to 233N based on the torque command to generate the corresponding torque. Each motor 2331 to 233N is connected to the wheel to drive the wheel forward.

[0091] During braking, the driver depresses the brake pedal, and first controller 221 controls hydraulic brake system 231 to implement hydraulic braking. The integrated booster in hydraulic brake system 231 then feeds back the hydraulic brake drive command to the vehicle controller. The vehicle controller then calculates and transmits modified torque commands for each motor 2331-233N to third controller 223. Third controller 223 adjusts the speed of each motor 2331-233N based on the modified torque commands to implement the modified drive torque.

[0092] In some embodiments, the main controller 210, the first controller 221, the second controller 222 and the third controller 223 are separately provided. Figure 2a shown.

[0093] Alternatively, in some other embodiments, at least two of the main controller 210, the first controller 221, the second controller 222, and the third controller 223 are integrated together. For example, in one example, Figure 2b As shown, the second controller 222 is integrated into the first controller 221. For example, in another example, Figure 2c As shown, the third controller 223 is integrated into the main controller 210. For example, in another example, Figure 2d As shown, the second controller 222 is integrated into the first controller 221, and the third controller 223 is integrated into the main controller 210. And so on, which are not listed one by one.

[0094] In some embodiments, the braking control system 200 also has an energy recovery braking function. For a vehicle with the energy recovery button turned on, when the vehicle decelerates or brakes, each motor 2331-233N can convert a portion of the vehicle's braking mechanical energy into electrical energy and store it in the power battery pack. When the vehicle accelerates again, each motor 2331-233N converts the energy stored in the power battery pack back into kinetic energy for vehicle travel. By recovering braking energy, the vehicle's range can be increased, energy waste can be reduced, and in some cases, the life of the brakes can be extended.

[0095] At least two motors 2331 - 233N, which can be hub motors or wheel-side motors, are deployed on at least two axles of the vehicle, with each motor connected to one or more wheels on the deployed axle.

[0096] Take the deployment of hub motors on a two-axle vehicle as an example, please refer to Figure 3 , shows a schematic diagram of the connection relationship between a motor and a wheel provided by the present application. This diagram can be understood as the structure obtained by looking from the bottom of the vehicle to the vehicle chassis. Figure 3 As shown in the figure, there are four ways to deploy the motor:

[0097] Motor deployment method 1, such as Figure 3 As shown in (A), at least two motors 2331 to 233N include motors 2331, 2332, and 2333. Motor 2331 is deployed on the front axle and is connected to both the left front wheel 100-1 and the right front wheel 100-2. Motors 2332 and 2333 are deployed on the rear axle and are connected to the left rear wheel 100-3 and the right rear wheel 100-4, respectively. Based on this deployment, the left front wheel 100-1 and the right front wheel 100-2 share the same motor 2331. This motor 2331 distributes the total torque of the front axle to the left front wheel 100-1 and the right front wheel 100-2, so that the sum of the torque output by the left front wheel 100-1 and the torque output by the right front wheel 100-2 equals the total torque of the front axle. The left rear wheel 100 - 3 and the right rear wheel 100 - 4 have their own independent motors 2332 and 2333 . The motor 2332 controls the output torque of the left rear wheel 100 - 3 , and the motor 2333 controls the output torque of the right rear wheel 100 - 4 .

[0098] Motor deployment method 2, such as Figure 3 As shown in (B), at least two motors 2331-233N include motors 2331 and 2332. Motor 2331 is deployed on the front axle and is connected to both the left front wheel 100-1 and the right front wheel 100-2. Motor 2332 is deployed on the rear axle and is connected to both the left rear wheel 100-3 and the right rear wheel 100-4. Based on this deployment, the left front wheel 100-1 and the right front wheel 100-2 share the same motor 2331. Motor 2331 distributes the total torque of the front axle to the left front wheel 100-1 and the right front wheel 100-2, so that the sum of the torque output by the left front wheel 100-1 and the torque output by the right front wheel 100-2 equals the total torque of the front axle. The left rear wheel 100-3 and the right rear wheel 100-4 also share the same motor 2332, which distributes the total torque of the rear axle to the left rear wheel 100-3 and the right rear wheel 100-4, so that the sum of the torque output by the left rear wheel 100-3 and the torque output by the right rear wheel 100-4 is equal to the total torque of the rear axle;

[0099] Motor deployment method three, such as Figure 3 As shown in (C), at least two motors 2331 to 233N include motors 2331, 2332, 2333, and 2334. Motors 2331 and 2332 are deployed on the front axle and are connected to the left front wheel 100-1 and the right front wheel 100-2, respectively. Motors 2333 and 2334 are deployed on the rear axle and are connected to the left rear wheel 100-3 and the right rear wheel 100-4, respectively. Based on this deployment method, the left front wheel 100-1, the right front wheel 100-2, the left rear wheel 100-3, and the right rear wheel 100-4 have their own independent motors 2331, 2332, 2333, and 2334. Motor 2331 controls the output torque of the left front wheel 100-1, motor 2332 controls the output torque of the right front wheel 100-2, motor 2333 controls the output torque of the left rear wheel 100-3, and motor 2334 controls the output torque of the right front wheel 100-4.

[0100] Motor deployment method four, such as Figure 3 As shown in (D), at least two motors 2331-233N include motors 2331, 2332, and 2333. Motors 2331 and 2332 are deployed on the front axle and connected to the left front wheel 100-1 and the right front wheel 100-2, respectively. Motor 2333 is deployed on the rear axle and connected to the left rear wheel 100-3 and the right rear wheel 100-4. Based on this deployment, the left front wheel 100-1 and the right front wheel 100-2 have their own independent motors 2331 and 2332. Motor 2331 controls the output torque of the left front wheel 100-1, and motor 2332 controls the output torque of the right front wheel 100-2. The left rear wheel 100-3 and the right rear wheel 100-4 share the same motor 2333, which distributes the total torque of the rear axle to the left rear wheel 100-3 and the right rear wheel 100-4, so that the sum of the torque output by the left rear wheel 100-3 and the torque output by the right rear wheel 100-4 is equal to the total torque of the rear axle.

[0101] It should be noted that Figure 3 The various figures shown in the figure all take the hub motor as an example, but in other examples, at least two motors 2331~233N can also be wheel-side motors, or a combination of a hub motor and a wheel-side motor, such as motor 2331 is a hub motor, motor 2333 is a wheel-side motor, and so on. This application does not make specific limitations on this.

[0102] In addition, although Figures 2a to 3 Although not shown in the figure, the vehicle may also have other modules or components, such as a communication module, an entertainment module, an intelligent driving module, an on-board camera, and an on-board radar, etc., which are not listed here one by one.

[0103] Based on the above Figure 2a to Figure 3 The content shown and the other content mentioned above, Figure 4A possible flow chart of a braking control method provided by an embodiment of the present application is exemplarily shown. The method can be executed by a vehicle, and more specifically, can be executed by a braking control device in the vehicle. The braking control device can be, for example, Figures 2a to 2d Each controller in, such as Figure 2a The main controller 210 and the first controller 221 to the third controller 223, or Figure 2b The main controller 210, the first controller 221 and the third controller 223, or Figure 2c The main controller 210, the first controller 221 and the second controller 222, or Figure 2d The main controller 210 and the first controller 221 in.

[0104] For ease of understanding, the following Figure 2a The controller architecture shown is used as an example, but it should be understood that the relevant content is also applicable to Figure 2b to Figure 2d The controller architecture shown in Figure 1 is as follows. For example, if Figure 2b If the controller architecture shown is as follows, the content about the second controller 222 is executed by the first controller 221. Figure 2c If the controller architecture shown is as follows, the content about the third controller 223 is executed by the main controller 210. Figure 2d In the controller architecture shown below, the content about the second controller 222 is executed by the first controller 221, and the content about the third controller 223 is executed by the main controller 210. This application does not repeat the relevant content.

[0105] like Figure 4 As shown, the braking control method includes step 401 and step 402, which are described below in conjunction with the accompanying drawings.

[0106] Step 401: Receive a braking request.

[0107] Optionally, the braking request may be any signal or instruction indicating that the vehicle may decelerate or brake, including but not limited to: a request generated by a user pressing the brake pedal, an automatic parking assist (APA) request, a remote parking assist (RPA) request, an adaptive cruise control (ACC) request, an autonomous emergency braking (AEB) request, an anti-lock braking system (ABS) request, etc.

[0108] For example, in some examples, the vehicle is in manual driving mode, and the driver generates a braking request by stepping on the brake pedal. The brake pedal is connected to the first controller 221 via a line, such as a brake cable. The first controller 221 obtains information related to the driver's brake pedal application, such as speed, travel, and pressure, and determines the braking torque. The braking torque has a certain correlation with the pedal speed, travel, and pressure information. This correlation is usually calibrated in advance. By substituting the actual information into the correlation, the required braking torque can be determined.

[0109] In this correlation, if the brake pedal is depressed quickly, or the pressure is high enough, or the pedal travel is long, or the increase in pedal travel within a preset time is large, the braking torque is generally high, the vehicle requires emergency braking, and the required target deceleration is large. Conversely, if the brake pedal is depressed slowly, or the pressure is low, or the pedal travel is short, or the increase in pedal travel within a preset time is small, the braking torque is relatively low, the vehicle can be braked slowly, and the required target deceleration is small.

[0110] For example, in other examples, the vehicle is in autonomous driving mode and is equipped with a brake kinetic energy button or an AEB function button. The driver generates a braking request by pressing these buttons. The main controller 210 receives an indication that the braking function or AEB function has been triggered and determines that the vehicle has a braking intention. In addition, if the vehicle's ABS function is enabled, the main controller 210 can also determine that a braking intention has occurred, and this braking intention is typically an emergency braking intention.

[0111] It should be understood that whether there is a braking intention may also be determined based on other information, and this application does not limit this.

[0112] Step 402: Based on the braking request, determine that the vehicle's hydraulic braking system has failed and that the vehicle's battery pack energy recovery capability limits the motor recovery intensity, control the vehicle's first motor braking, control the vehicle's second motor driving, and brake the wheels corresponding to the vehicle's second motor through the EPB system.

[0113] Optionally, after determining that the vehicle's battery pack energy recovery capability limits the motor recovery intensity, the main controller 210 may send a first braking instruction to the third controller 223. The third controller 223 controls one motor or part of the vehicle's motor to brake and another motor or another part of the motor to drive according to the first braking instruction. At the same time, the wheels corresponding to the driven motors are superimposed with EPB dynamic braking.

[0114] Optionally, the braking motor and the driving motor may be located on the same shaft, or may be located on different shafts.

[0115] For example, taking the example of being located on different axes, the vehicle may also include a first axis and a second axis, the first axis being provided with one or more motors, and the second axis being provided with one or more motors. After determining that the energy recovery capability of the vehicle's battery pack limits the motor recovery intensity, the main controller 210 may send a first braking instruction to the third controller 223 and simultaneously send a second braking instruction to the second controller 222. The third controller 223 controls the braking of all or part of the one or more motors of the first axis of the vehicle, and controls the driving of all or part of the one or more motors of the second axis of the vehicle, according to the first control instruction. The second controller 222 controls the EPB system to dynamically brake the wheels connected to the second axis, according to the second control instruction.

[0116] In some examples, in order to ensure the smoothness of vehicle driving, the main controller 210 can control the braking of all motors of the first axis and the driving of all motors of the second axis through the third controller 223. Figure 3 The four motor layouts shown are examples:

[0117] in the case of Figure 3 The motor layout shown in (A) can control the front axle motor 2331 to brake, the rear axle motors 2332 and 2333 to drive, and the rear axle superimposed with EPB dynamic braking; or control the rear axle motors 2332 and 2333 to brake, the front axle motor 2331 to drive, and the front axle superimposed with EPB dynamic braking;

[0118] in the case of Figure 3 The motor layout shown in (B) can control the front axle motor 2331 to brake, the rear axle motor 2332 to drive, and the rear axle to superimpose EPB dynamic braking; or control the rear axle motor 2332 to brake, the front axle motor 2331 to drive, and the front axle to superimpose EPB dynamic braking;

[0119] in the case of Figure 3 The motor layout shown in (C) can control the front axle motors 2331 and 2332 to brake, the rear axle motors 2333 and 2334 to drive, and the rear axle superimposed with EPB dynamic braking; or control the rear axle motors 2333 and 2334 to brake, the front axle motors 2331 and 2332 to drive, and the front axle superimposed with EPB dynamic braking;

[0120] in the case of Figure 3 The motor layout shown in (D) can control the front axle motors 2331 and 2332 to brake, the rear axle motor 2333 to drive, and the rear axle to superimpose EPB dynamic braking; or, control the rear axle motor 2333 to brake, the front axle motors 2331 and 2332 to drive, and the front axle to superimpose EPB dynamic braking.

[0121] It should be understood that this application does not limit the number of motors actually braked by the first axis and the number of motors actually driven by the second axis. For example, all motors of the first axis may be braked and some motors of the second axis may be driven, or some motors of the first axis may be braked and all motors of the second axis may be driven, or some motors of the first axis may be braked and some motors of the second axis may be driven, and so on. There is no limitation.

[0122] Alternatively, in one example, all or part of the electrical energy generated by braking the first motor is used to drive the second motor. For example, all of the electrical energy generated by braking the first motor is used to drive the second motor. In this case, no electrical energy is recharged back to the vehicle's power battery pack.

[0123] Alternatively, in another example, part of the electrical energy generated by braking the first motor is used to drive the second motor, while the remaining energy is recharged back to the battery pack. In this case, some of the electrical energy is recharged back to the battery pack. The specific amount of energy recharged back to the battery pack can be determined based on actual scenario requirements or user configuration, as long as it does not exceed the actual allowable charging capacity of the battery pack.

[0124] In some examples, to maximize the utilization rate of electric energy recovery, the electric energy recharged to the battery pack can be configured to be equal to the maximum allowable charging energy of the battery pack. The portion of electric energy that exceeds the maximum allowable charging energy of the battery pack is then used to drive the second motor. Although the second motor is in the driving state, the EPB system simultaneously performs dynamic braking on the wheels corresponding to the second motor. The ability of this dynamic braking is usually much greater than the driving ability of the second motor. Therefore, the wheels corresponding to the second motor are actually still in the braking state. In this way, the superposition of the braking of the first motor and the EPB dynamic braking of the wheels corresponding to the second motor can provide a relatively large deceleration, thereby achieving effective deceleration or braking of the vehicle.

[0125] With the above braking control method, after the hydraulic braking system fails, if the energy recovery capacity of the vehicle's battery pack limits the motor recovery intensity, it means that the actual allowable charging capacity of the battery pack cannot reach the charging capacity required for the expected deceleration. In this case, by controlling the braking of the vehicle's first motor and the EPB dynamic braking of the superimposed wheels driven by the second motor, it is possible to achieve a relatively large deceleration and a better braking effect through the braking of the first motor and the EPB dynamic braking of the wheels corresponding to the second motor, and to consume the excess electrical energy generated by the braking of the first motor through the drive of the second motor. Without exceeding the actual allowable charging capacity of the battery pack, the vehicle's recovery deceleration is fully utilized to ensure that the vehicle can have a large deceleration.

[0126] It should be noted that in the above braking control method, the electrical energy generated by the first motor braking that exceeds the battery pack's recovery capacity or all of the electrical energy is used to drive the second motor, rather than being recharged back into the battery pack. The drive of the second motor itself can be physically braked by the EPB system. In theory, physical braking is much greater than the drive of the motor, so the combination of these three can provide relatively large braking capacity. In other words, the above braking control method provides a new torque distribution method that is not limited by the energy recovery capacity of the battery pack, can achieve a large deceleration, and can be adapted to emergency braking scenarios, or non-emergency braking scenarios where the battery pack recovery capacity is insufficient.

[0127] In the above description, if the vehicle is a two-axle vehicle, the first axle is the front axle and the second axle is the rear axle, or the first axle is the rear axle and the second axle is the front axle.

[0128] In the current vehicle manufacturing process, for the sake of vehicle braking stability, the EPB system is usually set on the rear axle, and the EPB system performs dynamic braking on the rear axle wheels. In this case, the first axle is the front axle and the second axle is the rear axle. For ease of understanding, the following description will be based on the example that the first axle is the front axle and the second axle is the rear axle. However, it should be understood that the "front axle" below can also be replaced by the "first axle" or "rear axle", and the "front axle" below can also be replaced by the "first axle" or "rear axle". Alternatively, if the vehicle has more than two axles, the "front axle" below can also be replaced by an axle at any position, and the "rear axle" below can also be replaced by an axle at any position other than the position corresponding to the "front axle". This application does not make specific restrictions on this.

[0129] For further information on the program, see Figure 5 , showing a specific implementation flow chart of the braking control method provided in this application.

[0130] like Figure 5 As shown, the method includes steps 501 to 509, which are described below with reference to the accompanying drawings.

[0131] Step 501: Receive a braking request.

[0132] Step 502 , determining whether the hydraulic brake system has failed, if not, executing step 503 , if yes, executing step 504 .

[0133] Optionally, upon receiving a braking request, the main controller 210 or the first controller 221 uses the hydraulic braking system 231 to brake the vehicle by default. The main controller 210 or the first controller 221 can issue a braking instruction to the hydraulic braking system 231 based on the braking request to drive the hydraulic braking system 231 to hydraulically brake the wheels of the first axle and the wheels of the second axle of the vehicle.

[0134] Optionally, the main controller 210 can also monitor the failure of the hydraulic control system 231 in real time. If the vehicle actually begins braking within the first time period after the braking command is issued, it indicates that the hydraulic braking system 231 is braking normally and has not failed. The hydraulic braking system 231 can continue to brake the vehicle. Conversely, if the vehicle still does not begin braking within the first time period after the braking command is issued, and / or the main controller 210 receives fault information returned by the first controller 221 or the hydraulic control system 231, it indicates that the hydraulic braking system 231 has failed, the current braking demand cannot be met by the hydraulic braking system 231, and it is necessary to switch to another braking method.

[0135] In some scenarios, if the vehicle is in manual driving mode and the driver steps on the brake pedal, the first controller 221 calculates the braking torque based on the current degree of the brake pedal depression and controls the hydraulic brake system 231 to brake the vehicle according to this braking torque. While the hydraulic brake system 231 is braking the vehicle, the first controller 221 also transmits the hydraulic brake status to the CAN bus. If the hydraulic brake system 231 fails, the first controller 221 also transmits fault information about the hydraulic brake system 231 to the CAN bus. The main controller 210 reads this fault information from the CAN bus and determines that the hydraulic brake system 231 has failed.

[0136] In some scenarios, if the vehicle is in autonomous driving mode, upon receiving a braking request, the main controller 210 can calculate the target deceleration required for vehicle braking based on the braking request, and then transmit the target deceleration in a braking command to the CAN bus. Typically, the first controller 221 receives the braking command on the CAN bus, calculates the required braking torque based on the target deceleration in the braking command, and controls the hydraulic braking system 231 to brake the vehicle according to the braking torque.

[0137] In autonomous driving mode, there are various ways to monitor the failure of hydraulic brake system 231. For example, in one possible failure monitoring method, first controller 221 monitors the braking performance of hydraulic brake system 231. If braking is not performed, it reports a fault message about hydraulic brake system 231 to main controller 210. Upon receiving this fault message, main controller 210 determines that hydraulic brake system 231 has failed. For another example, in another possible failure monitoring method, after issuing a braking command, main controller 210 starts a timer. When the timer reaches a set time, it checks whether the vehicle's speed has decreased. If not, it determines that hydraulic brake system 231 has failed.

[0138] Alternatively, there may be other failure monitoring methods, which are not specifically limited here.

[0139] Step 503: hydraulically brake the front axle wheels and the rear axle wheels through the hydraulic braking system.

[0140] Taking a four-wheeled vehicle as an example, four brake calipers are provided on each of the vehicle's four wheels, and the first controller 221 is connected to the four brake calipers via a hydraulic brake pipe. The first controller 221 responds to a braking request or a braking command from the main controller 210, calculates the required braking torque, and controls the booster motor to generate the braking torque. The braking torque is converted into braking force via the booster motor's transmission mechanism. The braking force, together with the push rod force generated by the brake pedal through the push rod mechanism, acts on the brake master cylinder and is converted into hydraulic pressure within the brake master cylinder. The brake fluid with hydraulic pressure acts on the four brake calipers through the brake fluid pipe, building up pressure in the four brake calipers and controlling the braking pressure, thereby achieving deceleration braking of the wheels.

[0141] Step 504 , determining whether the braking request can be achieved by pure electric motor regenerative braking or pure EPB dynamic braking, if so, executing step 505 , if not, executing step 506 .

[0142] Step 505 : Control the front axle motor and / or the rear axle motor to brake, or dynamically brake the rear axle wheels through the EPB system.

[0143] Alternatively, after hydraulic brake system 231 fails, if the vehicle currently has no other hydraulic brake system, such as an auxiliary hydraulic brake system, or if both the primary and auxiliary hydraulic brake systems fail, the vehicle can only respond to the braking request through electric motor regenerative braking and / or EPB dynamic braking. In this case, main controller 210 can determine whether the braking request can be met by purely electric motor regenerative braking and / or purely EPB braking.

[0144] If pure electric motor regenerative braking is possible, the main controller 210 may control the front axle motor and / or the rear axle motor to brake. The number of motors to brake may be determined based on the intensity of the braking demand. If the braking demand is strong, both the front and rear axle motors may be controlled for braking. If the braking demand is weak, only one axle, such as the rear axle motor, may be controlled for braking, leaving the front axle motor acting as a passive axle, neither braking nor driving, to improve braking stability.

[0145] If dynamic braking can be achieved by a pure EPB system, the main controller 210 may dynamically brake the rear axle wheels through the EPB system.

[0146] If the braking cannot be achieved by either pure motor regenerative braking or pure EPB system dynamic braking, the main controller 210 may determine that the braking needs to be achieved in combination with the motor regenerative braking and the EPB dynamic braking.

[0147] It should be noted that the above two judgment steps can be performed in sequence or in parallel.

[0148] If it is executed in parallel, then as long as it is determined that a certain braking method can realize the braking request, the braking method can be directly used to respond to the braking request, and the judgment operation of the other braking method is stopped at the same time.

[0149] If it is executed sequentially, it can be first determined whether the braking request can be achieved by pure electric motor recovery braking, and if not, then determine whether the braking request can be achieved by pure EPB braking. It can also be first determined whether the braking request can be achieved by pure EPB braking, and if not, then determine whether the braking request can be achieved by pure electric motor recovery braking. The specific judgment order is not limited.

[0150] Step 506 , determining whether the vehicle's battery pack energy recovery capability limits the motor recovery intensity, if so, executing step 507 , if not, executing step 508 .

[0151] Here, after the main controller 210 determines that it is necessary to combine motor regenerative braking and EPB dynamic braking to achieve vehicle braking, in order to avoid the electric energy backcharged to the battery pack during motor regenerative braking exceeding the actual receivable electric energy of the battery pack, it can also first determine whether the vehicle's battery pack energy recovery capacity limits the motor recovery intensity.

[0152] For example, the main controller 210 can first calculate the braking capacity required by the motor regenerative braking based on the braking capacity required by the braking request and the current maximum braking capacity of the EPB system. It then determines whether the charging parameters corresponding to this braking capacity exceed the actual maximum charging parameters allowed by the battery pack, or whether this braking capacity exceeds the actual maximum braking capacity allowed by the battery pack. If so, it indicates that the battery pack's energy recovery capacity limits the motor regenerative braking intensity, and the process jumps to step 506. If not, it indicates that the battery pack's energy recovery capacity does not limit the motor regenerative braking intensity, and the process jumps to step 507.

[0153] Step 507 , controlling the front axle motor to brake and the rear axle motor to drive, while dynamically braking the rear axle wheels through the EPB system.

[0154] Here, when the battery pack's energy recovery capacity limits the motor recovery intensity, the front and rear axle motors cannot be directly controlled to brake. Otherwise, the electric energy generated by braking the front and rear axle motors will exceed the recovered electric energy of the battery pack, causing the battery pack to overcharge.

[0155] In this case, to maximize the battery's recovery capacity and achieve greater deceleration, the main controller 210 can control the front axle motor braking and rear axle motor driving via the third controller 223, while simultaneously controlling the EPB system to apply dynamic braking to the rear axle wheels via the second controller 222. There are two specific implementations of front axle motor braking and rear axle motor driving: one is to use all the electrical energy generated by the front axle motor braking to drive the rear axle motor; the other is to provide a portion of the electrical energy generated by the front axle motor braking to the battery pack and the remaining portion to drive the rear axle motor. The ratio of electrical energy provided to the battery pack and used for rear axle motor driving can be configured based on actual scenarios or can be set by those skilled in the art based on experience. Customized designs can also be supported, and are not limited to these.

[0156] In one example, in order to make full use of the limited charging capacity of the battery pack, the part of the electric energy generated by the front axle motor braking that can be received by the battery pack can be provided to the battery pack, and the remaining electric energy is used to drive the rear axle motor. For example, assuming that the motor recovery intensity is 20KW (kilowatts), that is, the motor recovery is required to provide 20KW of braking power, but the current energy recovery capacity of the battery pack can only recover 10KW. In this case, the front axle motor can be braked to generate 20KW of braking power, of which 10KW of braking power is recharged to the battery pack, and the extra 10KW of braking power is used to drive the rear axle motor. In this way, the rear axle motor will not have too much driving force, which is easier or more beneficial for the dynamic braking of the rear axle wheels of the EPB system.

[0157] Alternatively, since the front axle motor is braking and the rear axle motor is driving, the currents of the front and rear axle motors are in opposite directions. If the current corresponding to battery regeneration is negative, then braking the front axle motor generates a negative current, while driving the rear axle motor generates a positive current.

[0158] Based on this, when the braking control method is applied to any new energy electric vehicle, when the vehicle battery pack is fully charged, if the hydraulic braking system fails, then when the vehicle presses the brake pedal, or the intelligent driving system requests deceleration, the vehicle's front axle motor will be in recovery mode (the external current acquisition device collects negative current), and the rear axle motor will be in driving mode (the external current acquisition device collects positive current). At the same time, the EPB system is in dynamic braking state (the rear axle wheel caliper is clamped).

[0159] Step 508 : Control the front axle motor and / or the rear axle motor to brake, and at the same time, dynamically brake the rear axle wheels through the EPB system.

[0160] Here, if the battery pack's energy recovery capability does not limit the motor regenerative braking intensity, main controller 210 can combine EPB dynamic braking and default motor regenerative braking to achieve vehicle braking. EPB dynamic braking is understood as dynamic braking of the rear axle wheels via the EPB system. Default motor regenerative braking can be understood as controlling the braking of at least one motor on at least one axle of the vehicle. At least one motor on another axle may or may not brake, depending on the desired braking intensity.

[0161] For example, when the required braking intensity is relatively low, the braking capacity generated by braking only one axle motor is sufficient to meet the braking requirement. In this case, the main controller 210 can control only the front axle motor to brake, and the rear axle motor to not brake and serve only as a passive wheel, through the third controller 223, or control only the rear axle motor to brake, and the front axle motor to not brake and serve only as a passive wheel. This braking method can provide the required braking torque while avoiding unnecessary braking power loss, thereby improving energy utilization.

[0162] For example, when the required braking intensity is high, the braking capacity generated by braking only one axle motor cannot meet the braking demand. In this case, the main controller 210 can control the braking of both the front axle motor and the rear axle motor through the third controller 223. With this braking method, the power generated by braking both the front axle motor and the rear axle motor will not exceed the regenerative power of the battery pack, thereby preventing the battery pack from overcharging and providing a greater braking effect.

[0163] It is understandable that there may be other braking methods for the front axle motor and / or the rear axle motor, and this application does not specifically limit this.

[0164] In some scenarios, assuming that the vehicle's pure electric motor regenerative braking capability is less than the pure EPB dynamic braking capability, or in other words, the deceleration that can be provided by pure electric motor regenerative braking is less than the deceleration that can be provided by pure EPB dynamic braking, then in the above step 504, in order to fully save braking energy, it is possible to first determine whether the pure electric motor regenerative braking can respond to the braking request. If it cannot respond, it is then determined whether the pure EPB dynamic braking can respond to the braking request.

[0165] Based on this, see Figure 6 , showing a schematic diagram of a specific braking control method provided by this application, which can be understood as the above Figure 5 A specific implementation of steps 504 to 508 in the process shown. The method includes the following steps:

[0166] Step 601: Calculate the target deceleration of the vehicle according to the braking request.

[0167] Here, in the normal driving mode, if it is detected that the vehicle has a braking demand and the hydraulic brake system 231 fails, the main controller 210 can calculate the target deceleration required for the entire vehicle according to the braking request and the current working conditions.

[0168] Step 602 , determining whether the expected charging power corresponding to the target deceleration is less than or equal to the actual maximum charging power allowed by the battery pack; if so, executing step 603 ; otherwise, executing step 604 .

[0169] Optionally, the main controller 210 is also connected to the vehicle's battery management system (BMS). The BMS periodically monitors the vehicle's battery pack's temperature, charge level, pressure, and other information. Based on this information, it calculates the maximum allowable charging power of the vehicle's battery pack during each cycle and sends it to the main controller 210.

[0170] In one exemplary determination strategy, after calculating the target deceleration, the main controller 210 may convert the target deceleration into a corresponding braking torque and multiply the braking torque by the speed corresponding to the current vehicle speed to convert the target deceleration into the desired charging power. The main controller 210 compares the desired charging power with the actual maximum allowable charging power of the battery pack during the current cycle. If the desired charging power is less than or equal to the actual maximum allowable charging power of the battery pack, the target deceleration can be achieved using purely electric motor regenerative braking, and the process proceeds to step 603. If the desired charging power is greater than the actual maximum allowable charging power of the battery pack, the target deceleration cannot be achieved using purely electric motor regenerative braking, and the process proceeds to step 604.

[0171] Alternatively, in another exemplary determination strategy, the opposite calculation logic may be used to determine whether the target deceleration is less than or equal to the maximum deceleration corresponding to the actual maximum allowable charging power of the battery pack. For example, the main controller 210 may divide the actual maximum allowable charging power of the battery pack in the current cycle by the speed corresponding to the current vehicle speed to obtain the maximum braking torque that can be provided by battery pack recovery. The maximum braking torque is then converted into a maximum deceleration, and finally the target deceleration is compared with the maximum deceleration that can be provided by battery pack recovery. If the target deceleration is less than or equal to the maximum deceleration that can be provided by battery pack recovery, it indicates that the target deceleration can be achieved by pure electric motor regenerative braking, and the process jumps to step 603. If the target deceleration is greater than the maximum deceleration that can be provided by battery pack recovery, it indicates that the target deceleration cannot be achieved by pure electric motor regenerative braking, and the process jumps to step 604.

[0172] Step 603: Control the front axle motor and / or the rear axle motor to brake.

[0173] If main controller 210 determines that the target deceleration can be achieved using purely electric motor regenerative braking, it sends a braking command to third controller 223. Based on the braking command, third controller 223 controls at least one front axle motor and / or at least one rear axle motor to brake, for example, all front axle motors and all rear axle motors to brake, to maintain braking stability. During the braking process, the front and rear axle motors generate a drag torque on the wheels, thus braking the vehicle.

[0174] For example, when the front and rear axle motors are braking together, the electrical energy generated by both the front and rear axle motors during pure motor regenerative braking is recharged back into the battery pack. Because the battery pack's current maximum allowable power can deliver the target deceleration, the combined electrical energy generated by the motors on both axles does not exceed the battery pack's maximum allowable charge capacity, maximizing braking energy recovery and improving the vehicle's range.

[0175] Step 604 , determining whether the target deceleration is less than or equal to the maximum braking deceleration of the EPB system, if so, executing step 605 , if not, executing step 606 .

[0176] Here, the maximum deceleration of the EPB system can be understood as the maximum deceleration that the EPB system can provide on the current road, which is related to the maximum deceleration of the EPB system's initial configuration, the actual vehicle, and the actual road conditions. For example, the maximum deceleration of the EPB system's initial configuration is 0.2gm 2 / s, which means the EPB system can provide 0.2g when the rear wheel is clamped and not locked. 2 / s deceleration, but if 0.1gm is already applied to the rear wheel 2 / s corresponding driving force, it can be considered that the EPB system can only provide 0.1gm 2 / s deceleration, the maximum deceleration of the EPB system is 0.1gm 2 / s. For another example, assuming that the maximum deceleration of the EPB system is initially configured to be 0.3gm 2 / s, but the current road conditions are slippery. To prevent wheel lock, EPB dynamic braking can only achieve 0.1g. 2 / s deceleration, in this case, even if the motor can provide 0.2gm 2 / s driving force, the maximum rear axle deceleration that can be achieved by EPB dynamic braking is still 0.1gm 2 / s is not affected. And so on, I will not list them one by one here.

[0177] For example, assuming the maximum braking deceleration of the EPB system is 0.2gm 2 / s, if the target deceleration is less than or equal to 0.2gm 2 / s, indicating that the EPB system alone can provide the target deceleration, and the target deceleration can be achieved by dynamic braking of the pure EPB system, and the process jumps to step 605. On the contrary, if the target deceleration is greater than 0.2gm 2 / s, indicating that the EPB system alone cannot provide the target deceleration. Since pure motor regenerative braking alone cannot provide the target deceleration, the target deceleration needs to be achieved by combining the dynamic braking of the EPB system and the motor regenerative braking. Jump to step 606.

[0178] Step 605: Dynamically brake the rear axle wheels through the EPB system.

[0179] If the main controller 210 determines that the target deceleration can be achieved using pure EPB dynamic braking, it sends a braking command to the second controller 222. Based on the braking command, the second controller 222 controls the EPB system to dynamically brake the rear wheels. For example, it controls the clamping and releasing of the electronic parking brake motors on the left and right rear wheels to simulate the anti-lock braking function during hydraulic braking, achieving dynamic braking of the vehicle. During dynamic braking, controlling the clamping and releasing of the calipers prevents wheel locking, enabling the vehicle to achieve a higher deceleration and meet the target deceleration requirement.

[0180] Step 606 : Determine the motor recovery deceleration based on the target deceleration and the maximum braking deceleration of the EPB system.

[0181] Here, the main controller 210 may use the difference between the target deceleration and the maximum braking deceleration of the EPB system as the motor recovery deceleration, that is, the deceleration required to be provided by the motor recovery.

[0182] Step 607 , determining whether the expected charging power corresponding to the motor recovery deceleration is greater than the actual maximum allowable charging power of the battery pack; if so, executing step 608 ; otherwise, executing step 609 .

[0183] Alternatively, in one example, the main controller 210 may first convert the motor regenerative deceleration into a corresponding braking torque, and then multiply the braking torque by the vehicle speed to obtain the required braking power, which is also the desired charging power. Assuming the calculated braking power is 20 kW, if the actual maximum allowable charging power of the battery pack is less than 20 kW, such as only 10 kW, then the desired charging power corresponding to the motor regenerative deceleration is determined to be greater than the actual maximum allowable charging power of the battery pack, and the process proceeds to step 608. If the actual maximum allowable charging power of the battery pack is greater than or equal to 20 kW, such as 30 kW, then the desired charging power corresponding to the motor regenerative deceleration is determined to be less than or equal to the actual maximum allowable charging power of the battery pack, and the process proceeds to step 609.

[0184] Alternatively, in another example, a reverse calculation can be performed. For example, the maximum allowable braking force is calculated based on the actual maximum allowable charging power of the battery pack in combination with information such as vehicle speed, and then converted into the maximum allowable deceleration. If the maximum allowable deceleration is less than the motor regenerative deceleration, it means that the expected charging power corresponding to the motor regenerative deceleration is greater than the actual maximum allowable charging power of the battery pack, and the process jumps to step 608. If the maximum allowable deceleration is greater than or equal to the motor regenerative deceleration, it means that the expected charging power corresponding to the motor regenerative deceleration is less than or equal to the actual maximum allowable charging power of the battery pack, and the process jumps to step 609.

[0185] Step 608: Control the front axle motor to brake and the rear axle motor to drive, and at the same time, dynamically brake the rear axle wheels through the EPB system.

[0186] For example, to maintain braking stability, main controller 210 can control all front axle motors to brake and all rear axle motors to drive, via third controller 223. Furthermore, the braking power generated by all front axle motors is equal to the desired charging power corresponding to the motor's regenerative deceleration. A portion of the braking power generated by all front axle motors is recharged back to the battery pack, with the remainder used to drive all rear axle motors. To maximize regenerative capability, the portion of braking power recharged back to the battery pack can be precisely equal to the battery pack's actual maximum allowable charging power.

[0187] Furthermore, the main controller 210 can control the EPB system, via the second controller 222, to dynamically brake the rear axle wheels. Furthermore, the braking deceleration generated by the EPB system's dynamic braking of the rear axle wheels is equal to the EPB system's maximum braking deceleration. In this way, the EPB system's dynamic braking is combined with the braking of the front axle motor to provide the vehicle's desired target deceleration.

[0188] For ease of understanding, the implementation of step 608 is described with a specific example:

[0189] Assume that the target deceleration required for the vehicle is 0.5gm based on the braking request. 2 / s, the maximum deceleration of the EPB system is initially configured to be 0.5gm 2 / s, but due to the limitation of road friction, the rear axle wheels can only achieve a maximum of 0.3gm 2 / s deceleration, in this case, the maximum deceleration of the EPB system is only 0.3gm 2 / s;

[0190] According to the target deceleration of the vehicle required 0.5gm 2 / s and the maximum braking deceleration of the EPB system is 0.3gm 2 / s, the braking deceleration required by the motor is calculated to be: 0.5gm 2 / s-0.3gm 2 / s=0.2gm 2 / s;

[0191] Based on the required motor-provided braking deceleration of 0.2gm 2 / s, when the battery pack energy recovery capacity limits the motor recovery intensity, the front axle motor is controlled to provide 0.2gm 2 / s deceleration, in this case, even if the rear axle motor outputs 0.2gm 2 / s acceleration corresponding to the torque, the EPB system can still achieve 0.3gm on the vehicle side 2 / s deceleration;

[0192] Thus, the 0.3gm provided by the EPB system 2 / s plus the 0.2gm provided by the rear axle motor brake 2 / s deceleration, together providing the 0.5gm required for the entire vehicle 2 / s deceleration.

[0193] Step 609 , controlling the front axle motor and / or the rear axle motor to brake, and at the same time dynamically braking the rear axle wheels through the EPB system.

[0194] For example, to maintain braking stability, the main controller 210 can control all front axle motors and all rear axle motors to brake via the third controller 223. Furthermore, the sum of the braking power generated by all front axle motors and all rear axle motors is equal to the desired charging power corresponding to the motor regenerative deceleration. The braking power generated by all front axle motors and all rear axle motors is fully recharged back into the battery pack.

[0195] Furthermore, the main controller 210 can control the EPB system, via the second controller 222, to dynamically brake the rear wheels. Furthermore, the braking deceleration generated by the EPB system's dynamic braking of the rear wheels is equal to the EPB system's maximum braking deceleration. In this way, the EPB system's dynamic braking combines the braking of the front and rear motors to provide the target deceleration required by the vehicle.

[0196] For ease of understanding, the implementation of step 609 is described with a specific example:

[0197] Assume again that the target deceleration required for the vehicle is 0.5gm based on the braking request. 2 / s, the maximum deceleration of the EPB system is initially configured to be 0.5gm 2 / s, but due to the limitation of road friction, the rear axle wheels can only achieve a maximum of 0.3gm 2 / s deceleration, in this case, the maximum deceleration of the EPB system is only 0.3gm 2 / s;

[0198] According to the target deceleration of the vehicle required 0.5gm 2 / s and the maximum braking deceleration of the EPB system is 0.3gm 2 / s, the braking deceleration required by the motor is calculated to be: 0.5gm 2 / s-0.3gm 2 / s=0.2gm 2 / s;

[0199] Based on the required motor-provided braking deceleration of 0.2gm 2 / s, when the battery pack energy recovery capability does not limit the motor recovery intensity, the front axle motor and / or the rear axle motor are controlled to provide 0.2gm 2 / s deceleration, so the 0.3gm provided by the EPB system 2 / s plus 0.2gm provided by the front and / or rear axle motor brakes 2 / s deceleration, together providing the 0.5gm required for the entire vehicle 2 / s deceleration.

[0200] Based on this, the braking control method provided in the above content can provide the target deceleration required by the vehicle and achieve better braking effect regardless of the working conditions or vehicle status without being limited by the energy recovery capability of the battery pack.

[0201] In order to further illustrate the solution, the braking control method mentioned above will be described from another perspective below.

[0202] See also Figure 7, shows an overall flow chart of the braking control method provided by the present application, the flow chart including the following steps:

[0203] Step 701: The main control system monitors the failure of the vehicle hydraulic brake system in real time.

[0204] Here, the main control system can be understood as the main controller 210 mentioned above, and optionally, it can also include the first controller 221. In other words, the real-time monitoring of failure of the service hydraulic brake system can be implemented by the main controller 210 alone, or by the main controller 210 in combination with the first controller 221. Please refer to the above description for details, and will not be repeated here.

[0205] Here, the service hydraulic brake system can be understood as the hydraulic brake system 231 mentioned above.

[0206] Step 702 , determine whether the vehicle hydraulic brake system has failed. If not, execute step 703 . If failed, execute step 704 .

[0207] Step 703, end.

[0208] Here, when the vehicle hydraulic brake system is not invalid, the braking control process is terminated, which can be understood as continuing to use the original braking control process, for example, controlling vehicle braking through the hydraulic brake system.

[0209] Step 704 : The vehicle hydraulic brake system fails, and the battery energy recovery capability is compared with the motor energy recovery strength.

[0210] Here, after the service hydraulic brake system fails, the main control system interacts with the vehicle's BMS, instructing the BMS to collect information such as the battery pack's charge level and temperature, calculate the pack's actual maximum allowable charging power, and feed it back to the main control system. The main control system then measures the battery's energy recovery capability based on the pack's actual maximum allowable charging power.

[0211] The main control system can also calculate the required motor recovery intensity based on the current braking demand and the dynamic braking capability of the EPB system, and then compare the battery energy recovery capability and the motor recovery intensity.

[0212] Step 705 : Check whether the battery energy recovery capability limits the motor recovery intensity. If not, proceed to step 706 . If so, proceed to step 707 .

[0213] Step 706 : The EPB system and the motor system perform recovery braking.

[0214] Here, if the battery's energy recovery capability is greater than or equal to the motor's recovery strength, it means that the battery pack capacity does not limit the motor's recovery capability, and the EPB system and motor system can be combined to brake the vehicle. For example, the vehicle's front axle motor is controlled to brake, while the rear axle motor is neither braked nor driven, and the EPB system is controlled to dynamically brake the rear axle wheels. Alternatively, the vehicle's rear axle motor is controlled to brake, while the front axle motor is neither braked nor driven, and the EPB system is controlled to dynamically brake the rear axle wheels. Alternatively, the vehicle's front and rear axle motors are controlled to brake, while the EPB system is controlled to dynamically brake the rear axle wheels.

[0215] In step 707 , the main control system calculates the maximum number of L motors on the front axle to be recovered and the number of K motors on the rear axle to be driven, and at the same time, the EPB system of the rear axle wheels is activated.

[0216] Here, if the battery energy recovery capacity is less than the motor recovery strength, it means that the battery pack capacity limits the motor recovery capacity. To maximize the utilization of the vehicle's recovery deceleration, the main control system uses L motors on the front axle for braking and K motors on the rear axle for driving. At the same time, the rear axle wheels are superimposed with the redundant parking brake system to control vehicle deceleration.

[0217] Wherein, L is an integer greater than or equal to 1, and K is an integer greater than or equal to 1.

[0218] In one example, the value of L is equal to the total number of motors on the front axle, and the value of K is equal to the number of motors on the rear axle.

[0219] For example, according to the required motor recovery intensity, all the motors on the front axle can be controlled to brake. The part of the electric energy generated by braking that does not exceed the actual maximum allowable charging power of the battery pack is recovered to the battery pack, and the part exceeding it is used to drive all the motors on the rear axle. At the same time, the EPB system is controlled to perform dynamic braking on the rear axle wheels.

[0220] The above braking control method provides a redundant electric brake regeneration strategy or control scheme for situations where the battery's available charging power is limited. This redundant control scheme is designed for redundant braking systems. For vehicles not equipped with redundant hydraulic brakes (also known as auxiliary hydraulic brakes), if the service hydraulic brake system fails and battery regeneration capacity is limited, but emergency braking is required, the vehicle will achieve optimal redundant braking by controlling the motor torque distribution and the parking redundant brake system, ensuring that the vehicle still has a high deceleration rate.

[0221] Based on the braking control method described above, the present application can also provide a braking control device, which can be used to execute the above braking control method. The relevant features can be found in the above embodiments and will not be repeated here.

[0222] In one possible implementation, Figure 8 FIG2 is a schematic diagram showing a possible structure of a brake control device provided by the present application. The brake control device 800 may include modules or units for implementing the above method embodiments.

[0223] For example, in one possible design, brake control device 800 includes a transceiver unit 810 and a control unit 820. Transceiver unit 810 may also be referred to as a communication unit, transceiver, transceiver, or transceiver device, and control unit 820 may also be referred to as a controller, control chip, control board, or control device. In some scenarios, control unit 820 may also be referred to as a processing unit, processor, processing chip, processing board, or processing device.

[0224] Optionally, the transceiver unit 810 is configured to perform the sending and receiving operations in the above-described braking control method, and the control unit 820 is configured to perform the control operations in the above-described braking control method. In some examples, the device in the transceiver unit 810 that implements the receiving function can be considered a receiving unit, and the device in the transceiver unit 810 that implements the sending function can be considered a sending unit, that is, the transceiver unit 810 includes a receiving unit and a sending unit.

[0225] The braking control device 800 can be the main controller or a module in the main controller (such as a circuit, chip or chip system, etc.) in the above-mentioned embodiment, or it can also be a logical node, logic module or software applied to the main controller or its module, or used in combination with the main controller or its module, which can realize all or part of the functions of the braking control device 800.

[0226] For example, in one embodiment, the transceiver unit 810 is used to receive a braking request, and the control unit 820 is used to determine, based on the braking request, that the hydraulic braking system of the vehicle has failed and that the energy recovery capability of the vehicle's battery pack limits the motor recovery intensity, and then control the braking of the first motor, control the driving of the second motor, and brake the wheels corresponding to the second motor through the EPB system.

[0227] In a possible implementation, the vehicle further includes a first shaft and a second shaft, the first motor is disposed on the first shaft, and the second motor is disposed on the second shaft.

[0228] In a further possible implementation, the first axle is a front axle, and the second axle is a rear axle.

[0229] In one possible implementation, all the electric energy generated by braking the first motor is used to drive the second motor; or, part of the electric energy generated by braking the first motor is recharged back to the battery pack, and the other part is used to drive the second motor.

[0230] In a possible implementation, the control unit 820 controls the first motor to brake and controls the second motor to drive, specifically, it may be: controlling all motors on the shaft where the first motor is located to brake and controlling all motors on the shaft where the second motor is located to drive.

[0231] In one possible implementation, after determining that the vehicle's hydraulic braking system has failed and before determining that the vehicle's battery pack energy recovery capability limits the motor recovery intensity, the control unit 820 is also used to: determine the target deceleration of the entire vehicle based on the braking request, and determine that the target deceleration is greater than the maximum braking deceleration of the EPB system.

[0232] In an example of the above implementation, the control unit 820 is also used to: if the target deceleration is less than or equal to the maximum braking deceleration of the EPB system, use the EPB system to brake the wheels corresponding to the second motor; or, if the expected charging power corresponding to the target deceleration is less than or equal to the actual maximum allowable charging power of the battery pack, control the braking of the first motor and / or the second motor, and the electric energy generated by the braking of the first motor and / or the second motor is recharged back to the battery pack.

[0233] In an example of the above implementation, the control unit 820 is also used to: if the target deceleration is greater than the maximum braking deceleration of the EPB system, but the vehicle's battery pack energy recovery capability does not limit the motor recovery intensity, then control the braking of the first motor and / or the second motor, and brake the wheels corresponding to the second motor through the EBP system.

[0234] In an example of the above implementation, the control unit 820 determines whether the vehicle's battery pack energy recovery capability limits the motor recovery intensity in the following manner: first, the motor recovery deceleration is determined based on the target deceleration and the maximum braking deceleration of the EPB system; then, it is determined whether the expected charging power corresponding to the motor recovery deceleration is greater than the actual allowed maximum charging power of the battery pack. If so, it is determined that the vehicle's battery pack energy recovery capability limits the motor recovery intensity; if not, it is determined that the vehicle's battery pack energy recovery capability does not limit the motor recovery intensity.

[0235] In one possible implementation, the control unit 820 determines that the hydraulic braking system of the vehicle has failed based on a braking request, which may be: issuing a braking command to the hydraulic braking system based on the braking request; receiving fault information of the hydraulic braking system; and / or the vehicle does not start braking within the first time period of issuing the braking command.

[0236] In a possible implementation, the control unit 820 is further configured to: based on the braking request, if it is determined that the hydraulic braking system has not failed, hydraulically brake the wheels corresponding to the first motor and the wheels corresponding to the second motor through the hydraulic braking system.

[0237] In a possible implementation, the braking request includes at least one of the following: a request generated by a user pressing a brake pedal, an automatic parking request, an adaptive cruise control request, and an automatic emergency braking request.

[0238] It is understandable that the division of units in the above-mentioned device is merely a division of logical functions, and one function may correspond to one functional unit, or two or more functions may be integrated into one functional unit. In actual implementation, all or part of the units may be integrated into one physical entity, or distributed across different physical entities. In addition, the above-mentioned functional units may be implemented in the form of hardware, software, or a combination of hardware and software. Whether a function is executed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel may use different methods to implement the described functions for specific applications, but such implementation should not be considered to be beyond the scope of this application.

[0239] In one example, the functional units in any of the above brake control devices 800 can be one or more integrated circuits configured to implement the above methods, such as: one or more application specific integrated circuits (ASICs), or, one or more central processing units (CPUs), one or more microprocessors (MCUs), one or more digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs), or a combination of at least two of these integrated circuit forms.

[0240] In another possible implementation, see Figure 9 , showing another possible structural schematic diagram of the brake control device. Figure 9The illustrated brake control device 900 includes at least one processor 910 and an interface circuit 920. The at least one processor 910 is coupled to a memory. Optionally, the memory may be located within the brake control device 900 and integrated with the processor 910, or may be located outside the brake control device 900. For example, the brake control device 900 may further include at least one memory 930. The at least one memory 930 stores the computer programs (or instructions) and / or data necessary to implement any of the aforementioned embodiments. The at least one processor 910 may execute the computer programs (or instructions) and / or data stored in the at least one memory 930 to implement the brake control method of any of the aforementioned embodiments.

[0241] The brake control device 900 can exchange information with other devices via an interface circuit 920. Exemplarily, the interface circuit 920 can be a transceiver, circuit, bus, module, pin, or other type of communication interface. When the brake control device 900 is a chip-type device or circuit, the interface circuit 920 in the brake control device 900 can also be an input / output circuit capable of inputting (or receiving) and outputting (or sending) information. The processor can be an integrated processor, microprocessor, integrated circuit, or logic circuit, and can determine output information based on input information.

[0242] The coupling in the embodiments of the present application is an indirect coupling or communication connection between devices, units, or modules, which can be electrical, mechanical, or other forms, and is used for information exchange between devices, units, or modules. The processor 910 may operate in conjunction with the memory 930 and the interface circuit 920. The specific connection medium between the processor 910, memory 930, and interface circuit 920 is not limited in the embodiments of the present application.

[0243] Optional, see Figure 9 The processor 910, the interface circuit 920, and the memory 930 are interconnected via a bus. The bus may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus. The bus may be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, Figure 9 Only one thick line is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0244] In the embodiments of the present application, the processor 910 can be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. A general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of the present application can be directly implemented as being executed by a hardware processor, or can be executed by a combination of hardware and software modules in the processor.

[0245] In an embodiment of the present application, the memory 930 may be a non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), or a volatile memory (volatile memory), such as a random-access memory (RAM). The memory 930 is any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory 930 in an embodiment of the present application may also be a circuit or any other device that can implement a storage function, for storing program instructions and / or data.

[0246] When the brake control device 900 is used to implement the above method embodiment, the interface circuit 920 is used to implement the functions of the above transceiver unit 810, and the processor 910 is used to implement the functions of the above control unit 820, which will not be repeated here.

[0247] Based on the above description, the present application can also provide a braking control system, such as Figure 10 The braking control system includes a braking control device 1010, which can be any of the aforementioned braking control devices, such as Figure 8 Brake control shown, or Figure 9 The brake control device shown is not specifically limited.

[0248] In one possible implementation, Figure 10 As shown, the brake control system may further include a hydraulic brake system 231, which is coupled to the brake control device 1010. The brake control device 1010 is configured to, upon receiving a brake request and if it determines that the hydraulic brake system has not failed, control the hydraulic brake system 231 to brake the wheels corresponding to the first motor and the wheels corresponding to the second motor of the vehicle.

[0249] In a further possible implementation, Figure 10As shown, the brake control system may further include a parking brake system 232, which is coupled to the brake control device 1010. The brake control device 1010 is further configured to, upon receiving a brake request, control the parking brake system 232 to apply a parking brake to the wheel corresponding to the second motor of the vehicle if it is determined that the hydraulic brake system has failed but the parking brake system 232 has not failed.

[0250] In a further possible implementation, Figure 10 As shown, the brake control system may further include N motors, such as motors 2331-233N, each of which is coupled to the brake control device 1010. The brake control device 1010 is further configured to, upon receiving a brake request, control the N motors 2331-233N to brake the first motor and / or the second motor of the vehicle if it is determined that the hydraulic brake system has failed but the N motors 2331-233N have not failed.

[0251] In one possible implementation, combining Figure 10 and the above Figures 2a to 2d The braking control device 1010 may specifically include a main controller 210 and a first controller 221. The main controller 210 is connected to the first controller 221, the parking brake system 232, and the N motors 2331 to 233N respectively. The first controller 221 is also connected to the hydraulic brake system 231. The main controller 210 is used to execute the steps in any of the above method embodiments and send braking instructions to the first controller 221, the parking brake system 232, and one or more of the N motors 2331 to 233N. The first controller 221 is used to control the hydraulic brake system 231 to hydraulically brake the wheels corresponding to the first motor and the wheels corresponding to the second motor according to the braking instructions. The parking brake system 232 is used to brake the wheels corresponding to the second motor according to the braking instructions. The N motors 2331 to 233N are used to brake or drive according to the braking instructions.

[0252] In a further possible implementation, combining Figure 10 and the above Figures 2a to 2d The brake control device 1010 may further include a second controller 222, which is connected between the main controller 210 and the parking brake system 232. The main controller 210 is further configured to send a braking command to the second controller 222, which controls the parking brake system 232 to brake the wheel corresponding to the second motor according to the braking command.

[0253] In a further possible implementation, combining Figure 10 and the above Figures 2a to 2dThe brake control device 1010 may further include a third controller 223 connected between the main controller 210 and the N motors 2331 to 233N. The main controller 210 is further configured to send a braking command to the third controller 223, which controls the braking or driving of the N motors 2331 to 233N according to the braking command.

[0254] It should be noted that the braking control system may also include other structures or devices, such as a mechanical transmission system, axles, brakes, sensors, etc., which are not specifically limited in this application.

[0255] Based on the above description, the present application may also provide a vehicle, which may include a brake control system or a brake control device. The brake control device may be any of the aforementioned brake control devices, such as Figure 8 Brake control shown, or Figure 9 The braking control system can be any of the aforementioned braking control systems, such as Figures 2a to 2d The braking control system 200 shown in any of the figures, or Figure 10 Brake control system shown.

[0256] Exemplarily, the above-mentioned vehicles may include, but are not limited to: cars, trucks, buses, recreational vehicles, amusement park vehicles, construction vehicles, trams, golf carts, trains, unmanned vehicles, smart cars and digital cars, etc.

[0257] Based on the braking control method described above, the present application can also provide a computer-readable storage medium, which stores a computer program or instruction. When the instruction is executed on a computer, the braking control method described in any of the above embodiments is implemented.

[0258] Based on the braking control method described above, the present application may also provide a computer program product, which includes a computer program. When the computer program is executed by a computer, the braking control method described in any of the above embodiments is implemented.

[0259] In this application, "at least one" means one or more, and "more than one" means two or more. "Including at least one" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple. "And / or" refers to any one or combination of two items. For example, A and / or B can represent: A, B, A and B. In addition, in this application, the word "exemplarily" or "optionally" is used to indicate an example, illustration or description. Any embodiment or design described as "example" or "optional" in this application should not be interpreted as being more preferred or more advantageous than other embodiments or design schemes. Alternatively, it can be understood that the use of the word "example" or "optional" is intended to present concepts in a specific way and does not constitute a limitation on this application.

[0260] It will be appreciated that the various numerical numbers involved in this application are merely for the purpose of describing the distinctions made, and are not intended to limit the scope of the embodiments of the present application. The size of the sequence numbers of the above-mentioned processes does not imply the order of execution, and the order of execution of each process should be determined by its function and inherent logic. Terms such as "first", "second", "third" and similar expressions are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, comprising a series of steps or units. Methods, systems, products or devices are not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

Claims

1. A braking control method, characterized in that: Applicable to a vehicle, the vehicle comprising a first motor and a second motor; The method comprises: receiving a braking request; Based on the braking request, it is determined that the hydraulic braking system of the vehicle has failed and the energy recovery capability of the battery pack of the vehicle limits the motor recovery intensity, the first motor is controlled to brake, the second motor is controlled to drive, and the wheels corresponding to the second motor are braked through the electronic parking brake EPB system.

2. The method according to claim 1, wherein The vehicle further includes a first shaft and a second shaft, the first motor is disposed on the first shaft, and the second motor is disposed on the second shaft.

3. The method according to claim 2, wherein The first axle is a front axle, and the second axle is a rear axle.

4. The method according to any one of claims 1 to 3, characterized in that The electric energy generated by the braking of the first motor is all used to drive the second motor; or, Part of the electric energy generated by braking the first motor is recharged back to the battery pack, and the other part is used to drive the second motor.

5. The method according to any one of claims 1 to 4, characterized in that The controlling the first motor to brake and the controlling the second motor to drive comprises: All motors on the shaft where the first motor is located are controlled to brake, and all motors on the shaft where the second motor is located are controlled to drive.

6. The method according to any one of claims 1 to 5, characterized in that After determining that the hydraulic brake system of the vehicle has failed and before determining that the battery pack energy recovery capability of the vehicle limits the motor recovery intensity, the method further includes: determining a target deceleration of the vehicle according to the braking request; The target deceleration is determined to be greater than a maximum braking deceleration of the EPB system.

7. The method according to claim 6, wherein The method further comprises: If the target deceleration is less than or equal to the maximum braking deceleration of the EPB system, the EPB system is used to brake the wheel corresponding to the second motor; or If the expected charging power corresponding to the target deceleration is less than or equal to the actual maximum allowable charging power of the battery pack, the first motor and / or the second motor are controlled to brake, and the electric energy generated by the braking of the first motor and / or the second motor is recharged back to the battery pack.

8. The method according to claim 6 or 7, wherein: The method further comprises: If the target deceleration is greater than the maximum braking deceleration of the EPB system, but the battery pack energy recovery capability of the vehicle does not limit the motor recovery intensity, the first motor and / or the second motor are controlled to brake, and the wheels corresponding to the second motor are braked through the EBP system.

9. The method according to any one of claims 6 to 8, characterized in that Determine whether the vehicle's battery pack energy recovery capability limits the motor recovery intensity by: determining a motor recovery deceleration according to the target deceleration and a maximum braking deceleration of the EPB system; If the expected charging power corresponding to the motor recovery deceleration is greater than the actual maximum allowable charging power of the battery pack, determining that the energy recovery capability of the battery pack of the vehicle limits the motor recovery intensity; If the expected charging power corresponding to the motor recovery deceleration is less than or equal to the actual allowed maximum charging power of the battery pack, it is determined that the battery pack energy recovery capability of the vehicle does not limit the motor recovery intensity.

10. The method according to any one of claims 1 to 9, characterized in that Determining, based on the braking request, that the hydraulic braking system of the vehicle has failed includes: issuing a braking command to the hydraulic braking system according to the braking request; Receiving fault information of the hydraulic brake system; and / or, During the first time period when the braking command is issued, the vehicle does not start braking.

11. The method according to any one of claims 1 to 10, characterized in that The method further comprises: According to the braking request, if it is determined that the hydraulic braking system has not failed, the wheels corresponding to the first motor and the wheels corresponding to the second motor are hydraulically braked by the hydraulic braking system.

12. The method according to any one of claims 1 to 11, characterized in that The braking request includes at least one of the following: Requests generated by the user pressing the brake pedal, automatic parking requests, adaptive cruise control requests, and automatic emergency braking requests.

13. A brake control device, characterized in that: The method comprises a unit or module for executing the method according to any one of claims 1 to 12.

14. A brake control device, characterized in that: The device comprises a processor and an interface circuit, wherein the processor is configured to communicate with other devices via the interface circuit to implement the method according to any one of claims 1 to 12.

15. A braking control system, characterized in that: include: a main controller, and a first controller; The first controller is connected to the hydraulic brake system of the vehicle, and the main controller is respectively connected to the first controller, the electronic parking brake EPB system of the vehicle, and the motor of the vehicle; The main controller is configured to execute the method according to any one of claims 1 to 11, and send a braking command to one or more of the first controller, the EPB system, and the motor; The first controller is configured to control the hydraulic braking system to perform hydraulic braking on the wheels of the vehicle according to the braking instruction; The EPB system is configured to brake the wheels of the vehicle according to the braking command; The motor of the vehicle is used to brake or drive the wheels of the vehicle according to the braking instruction.

16. The system according to claim 15, wherein: Also included is a second controller connected between the main controller and the EPB system; The main controller is further configured to send a braking instruction to the second controller; The second controller is used to control the EPB system to brake the wheels of the vehicle according to the braking instruction.

17. The system according to claim 15 or 16, characterized in that Also included is a third controller connected between the main controller and the motor of the vehicle; The main controller is further configured to send a braking instruction to the third controller; The third controller is used to control the motor braking or driving of the vehicle according to the braking instruction.

18. A vehicle, characterized in that: The brake control device comprises the brake control apparatus according to claim 13 or 14, or the brake control system according to any one of claims 15 to 17.

19. A computer-readable storage medium, characterized in that The storage medium stores a computer program or instruction, and when the computer program or instruction is executed, the method according to any one of claims 1 to 12 is implemented.

20. A computer program product, characterized in that The computer program product comprises instructions which, when executed, implement the method according to any one of claims 1 to 12.

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