Vehicle longitudinal controller and control method thereof

Abstract

The invention relates to a control method for a vehicle longitudinal controller VLC, the method comprising: receiving a target acceleration from an adaptive cruise control ACC device; determining that the vehicle longitudinal controller VLC is in a first operating mode based on the target acceleration; and in the first operating mode, sending a first torque request directly to a vehicle control unit VCU without passing via a controlled deceleration unit CDD of a brake energy recovery system CRBS or a driving assistance system. The invention also relates to a vehicle longitudinal controller VLC, a computer storage medium, a vehicle body stabilization system and a vehicle.

Description

Technical Field

[0001] This invention relates to a vehicle longitudinal controller (VLC), and more specifically, to a control method for a vehicle longitudinal controller (VLC), a vehicle longitudinal controller (VLC), a computer storage medium, a vehicle stability system, and a vehicle. Background Technology

[0002] For electric vehicles equipped with Adaptive Cruise Control (ACC), regenerative functions (such as Controlled Regeneration Brake System (CRBS), etc.), and OnePedal functionality, the CRBS now needs to operate during ACC to achieve maximum regenerative capacity and improve battery durability. Simultaneously, different torque requests from the Vehicle Longitudinal Controller (VLC) and the CRBS need to be merged into a single torque request interface to be sent to subsequent control units (such as the Vehicle Control Unit (VCU)).

[0003] However, in certain situations, especially when the control state changes (such as when ACC is activated or the driver overtakes), the torque request may change significantly, which can cause severe vehicle vibration and reduce the driving experience. Summary of the Invention

[0004] According to one aspect of the present invention, a control method for a vehicle longitudinal controller (VLC) is provided, the method comprising: receiving a target acceleration from an adaptive cruise control (ACC) device; determining that the vehicle longitudinal controller (VLC) is in a first operating mode based on the target acceleration; and in the first operating mode, directly sending a first torque request to a vehicle control unit (VCU) without passing through a brake energy recovery system (CRBS) or a controlled deceleration unit (CDD) of a driver assistance system. The first torque request may include a torque request value determined based on the target acceleration (positive for acceleration and negative for deceleration) (wherein the torque request value can be positive or negative).

[0005] As a supplement or replacement to the above solution, in the above method, determining that the vehicle longitudinal controller (VLC) is in a first operating mode based on the target acceleration includes: receiving a first parameter from the vehicle controller (VCU), the first parameter indicating a minimum adjustable torque value; determining a target torque value based on the target acceleration; and determining that the vehicle longitudinal controller (VLC) is in the first operating mode when the target torque value is greater than or equal to the minimum adjustable torque value.

[0006] As a supplement or replacement to the above solution, in the above method, when the target torque value is less than the minimum adjustable torque value, the vehicle longitudinal controller (VLC) is switched from the first operating mode to the second operating mode. In the second operating mode, the vehicle longitudinal controller (VLC) sends a second torque request to the vehicle controller (VCU) via the brake energy recovery system (CRBS) and the controlled deceleration unit (CDD) of the driver assistance system.

[0007] As a supplement or replacement to the above scheme, in the above method, both the first torque request and the second torque request are regenerative torque requests.

[0008] As a supplement or alternative to the above scheme, in the above method, the regenerative torque request includes a negative torque request value, which instructs the motor to reverse in order to recover energy.

[0009] As a supplement or replacement to the above scheme, in the above method, the first torque request is an acceleration torque request, and the acceleration torque request includes a positive torque request value.

[0010] As a supplement or replacement to the above scheme, in the above method, the first operating mode is acceleration control EC mode, and the second operating mode is deceleration control DC mode.

[0011] As a supplement or replacement to the above solution, in the above method, determining that the vehicle longitudinal controller (VLC) is in the first operating mode based on the target acceleration includes: determining a target torque value based on the target acceleration; determining the maximum regenerative capacity of the vehicle controller (VCU); and determining that the vehicle longitudinal controller (VLC) is in the first operating mode when the target torque value is greater than or equal to the maximum regenerative capacity.

[0012] As a supplement or replacement to the above solution, in the above method, when the target torque value is less than the maximum regeneration capacity, the vehicle longitudinal controller (VLC) is switched from the first operating mode to the second operating mode.

[0013] According to another aspect of the present invention, a vehicle longitudinal controller (VLC) is provided, the VLC comprising: a receiving unit for receiving a target acceleration from an adaptive cruise control (ACC) device; a determining unit for determining that the VLC is in a first operating mode based on the target acceleration; and a transmitting unit for transmitting a first torque request directly to a vehicle controller (VCU) in the first operating mode, without passing through a brake energy recovery system (CRBS) or a controlled deceleration unit (CDD) of a driver assistance system.

[0014] As a supplement or replacement to the above solution, in the above vehicle longitudinal controller (VLC), the determining unit is configured to: receive a first parameter from the vehicle controller (VCU), the first parameter indicating a minimum adjustable torque value; determine a target torque value based on the target acceleration; and determine that the vehicle longitudinal controller (VLC) is in the first operating mode when the target torque value is greater than or equal to the minimum adjustable torque value.

[0015] As a supplement or replacement to the above solution, the vehicle longitudinal controller (VLC) further includes: a first switching unit, used to switch the vehicle longitudinal controller (VLC) from the first operating mode to a second operating mode when the target torque value is less than the minimum adjustable torque value, wherein in the second operating mode, the vehicle longitudinal controller (VLC) sends a second torque request to the vehicle controller (VCU) via the brake energy recovery system (CRBS) and the controlled deceleration unit (CDD) of the driver assistance system.

[0016] As a supplement or replacement to the above scheme, in the above vehicle longitudinal controller (VLC), both the first torque request and the second torque request are regenerative torque requests.

[0017] As a supplement or alternative to the above scheme, in the above vehicle longitudinal controller (VLC), the regenerative torque request includes a negative torque request value, which instructs the motor to reverse in order to recover energy.

[0018] As a supplement or replacement to the above scheme, in the above vehicle longitudinal controller (VLC), the first torque request is an acceleration torque request, which includes a positive torque request value.

[0019] As a supplement or replacement to the above scheme, in the above vehicle longitudinal controller (VLC), the first operating mode is acceleration control (EC) mode, and the second operating mode is deceleration control (DC) mode.

[0020] As a supplement or replacement to the above solution, in the above vehicle longitudinal controller (VLC), the determining unit is configured to: determine a target torque value based on the target acceleration; determine the maximum regenerative capacity of the vehicle controller (VCU); and determine that the vehicle longitudinal controller (VLC) is in the first operating mode when the target torque value is greater than or equal to the maximum regenerative capacity.

[0021] As a supplement or replacement to the above solution, the vehicle longitudinal controller (VLC) may further include: a second switching unit, used to switch the vehicle longitudinal controller (VLC) from the first operating mode to the second operating mode when the target torque value is less than the maximum regeneration capacity.

[0022] According to another aspect of the present invention, a computer storage medium is provided, the medium including instructions that, when executed, perform the control method as described above.

[0023] According to another aspect of the invention, a vehicle stability system is provided, which includes the vehicle longitudinal controller (VLC) as described above.

[0024] As a supplement or replacement to the above solution, the above vehicle stability system may further include: a controlled deceleration unit (CDD), wherein the controlled deceleration unit (CDD) is configured to receive a current torque value and calculate a requested braking force based at least on both hydraulic pressure and the current torque value.

[0025] As a supplement or alternative to the above solution, the above vehicle stability system may further include: a brake energy recovery system (CRBS), wherein the brake energy recovery system is configured to limit the slope of replenishing brake fluid by means of a second parameter.

[0026] According to another aspect of the invention, a vehicle is provided that includes the vehicle stability system as described above.

[0027] The vehicle longitudinal controller (VLC) and its control method in embodiments of the present invention determine that the vehicle longitudinal controller is in a first operating mode based on the target acceleration received from the adaptive cruise control (ACC) device. In this operating mode, without going through other regenerative functions (such as brake energy regeneration system (CRBS)) and controlled deceleration unit (CDD), the torque request is directly sent to the vehicle control unit (VCU), enabling the vehicle longitudinal controller (VLC) to control not only the acceleration but also the deceleration of the vehicle. Furthermore, the torque request of the VLC includes a torque request value determined based on the target acceleration (wherein the torque request value can be positive or negative), thus ensuring that the torque request value is continuous and avoiding motor performance degradation due to large step changes. Attached Figure Description

[0028] The above and other objects and advantages of the present invention will become more fully clear from the following detailed description taken in conjunction with the accompanying drawings, wherein the same or similar elements are indicated by the same reference numerals.

[0029] Figure 1 A flowchart illustrating a control method for a vehicle longitudinal controller (VLC) according to an embodiment of the present invention is shown. Figure 2 A schematic diagram of the structure of a vehicle longitudinal controller (VLC) according to an embodiment of the present invention is shown; and Figure 3 A schematic diagram of a vehicle stability system according to an embodiment of the present invention is shown. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it.

[0031] It should also be noted that, for ease of description, the accompanying drawings show only the parts relevant to the invention and not all of them. Before discussing exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although the flowcharts describe the operations (or steps) as sequential processes, many of the operations can be performed in parallel, concurrently, or simultaneously. Furthermore, the order of the operations can be rearranged. The process can be terminated when its operation is completed, but it may also have additional steps not included in the drawings. The process may correspond to a method, function, procedure, subroutine, subprogram, etc.

[0032] Although exemplary embodiments are described as using multiple units to perform exemplary processes, it should be understood that these exemplary processes may also be performed by one or more modules.

[0033] Furthermore, the control logic of the present invention can be included as executable program instructions on a computer-readable medium, which are implemented by a processor or the like. Examples of computer-readable media include, but are not limited to, ROM, RAM, optical discs, magnetic tapes, floppy disks, flash drives, smart cards, and optical data storage devices. The computer-readable recording medium can also be distributed across a networked computer system, enabling distributed storage and implementation of the computer-readable medium, for example, via in-vehicle telecommunications services or a Controller Area Network (CAN).

[0034] Unless specifically mentioned or obvious from the context, the term “approximately” as used herein shall be understood as being within the range of normal tolerances in the art, such as within 2 standard deviations of the mean.

[0035] It should be understood that the term "vehicle" or other similar terms used herein include motor vehicles in general, such as passenger cars (including SUVs, buses, trucks, etc.), various commercial vehicles, etc., and includes hybrid vehicles, electric vehicles, etc. A hybrid vehicle is a vehicle with two or more power sources, such as a gasoline-powered and an electric vehicle.

[0036] In the following, the control schemes of the vehicle longitudinal controller (VLC) according to various exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0037] Figure 1A schematic flowchart of a control method 1000 for a vehicle longitudinal controller (VLC) according to an embodiment of the present invention is shown. Figure 1 As shown, the control method 1000 includes the following steps: In step S110, the target acceleration is received from the adaptive cruise control (ACC) device; In step S120, the vehicle longitudinal controller (VLC) is determined to be in a first operating mode based on the target acceleration; and In step S130, in the first operating mode, a first torque request is sent directly to the vehicle controller (VCU) without going through the brake energy recovery system (CRBS) or the controlled deceleration unit (CDD) of the driver assistance system.

[0038] In the context of this invention, the term "vehicle longitudinal controller" (VLC) refers to a device for controlling the longitudinal movement of a vehicle. In one embodiment, the vehicle longitudinal controller (VLC) may be a logic module within the Electronic Stability Program (ESP), specifically a longitudinal control module.

[0039] The term "Controlled Deceleration for Driver Assistance System" (CDD) is also known as driver assistance deceleration control. This controlled deceleration unit typically functions as a lower-level unit of the vehicle's longitudinal controller (VLC). It receives the target acceleration from the VLC and outputs the target braking force to lower-level units (such as the Driver Brake Request Module (DBR) and the Brake Energy Regeneration System (CRBS)) to brake the vehicle.

[0040] Adaptive Cruise Control (ACC) is an intelligent automatic control system. During vehicle operation, a distance sensor (radar) mounted at the front of the vehicle continuously scans the road ahead, while wheel speed sensors collect vehicle speed signals. When the distance to the vehicle ahead is too small, the ACC control unit coordinates with the anti-lock braking system (ABS) and engine control system to apply appropriate braking to the wheels and reduce engine output power, ensuring a safe distance is maintained. When controlling braking, the adaptive cruise control system typically limits deceleration to a level that does not affect comfort. When greater deceleration is required, the ACC control unit issues audible and visual signals to notify the driver to apply the brakes. When the distance to the vehicle ahead increases to a safe level, the ACC control unit controls the vehicle to travel at the set speed. In one or more embodiments of this invention, the aforementioned adaptive cruise control (ACC) device can be an ACC control unit.

[0041] In the context of this invention, the Vehicle Control Unit (VCU), or central control unit of a new energy vehicle, is the core of the entire control system. The VCU collects data such as motor and battery status, accelerator pedal signals, brake pedal signals, actuator and sensor signals, and, after comprehensively analyzing the driver's intentions and making corresponding judgments, monitors the actions of lower-level component controllers. It is responsible for the vehicle's normal operation, brake energy feedback, energy management of the vehicle's engine and power battery, network management, fault diagnosis and handling, and vehicle status monitoring, thereby ensuring the vehicle operates normally and stably with good power performance, high economy, and high reliability. It can be said that the performance of the VCU directly determines the overall performance of the new energy vehicle, playing a pivotal role.

[0042] The Regenerative Braking System (CRBS) recovers excess energy released during braking or coasting, converting it into electricity via a generator and storing it in the battery for subsequent acceleration. This battery also powers in-vehicle electrical devices, reducing reliance on the engine, fuel consumption, and CO2 emissions. Regenerative braking is a crucial technology in modern electric vehicles. In conventional internal combustion engine vehicles, the vehicle's kinetic energy is converted into heat through the braking system and released into the atmosphere during deceleration and braking. In electric or hybrid vehicles, this wasted kinetic energy is converted into electricity and stored in the battery, further converted into driving energy. For example, when starting or accelerating, requiring increased driving force, the electric motor provides auxiliary power to the engine, effectively utilizing electrical energy.

[0043] A typical scenario involves activating Adaptive Cruise Control (ACC) while the vehicle is coasting freely at 20 km / h. In this case, the torque request from the Vehicle Control Center (VLC) typically starts at 0 Nm, which differs from the actual torque requested by the Vehicle Control Unit (VCU), leading to vehicle vibration. Another scenario occurs when the vehicle is overtaking and the accelerator pedal is slowly released. Although some existing solutions propose that the torque request should follow the actual torque during overtaking, the torque request is still limited to 0 Nm because the parameter MpropMin (minimum adjustable torque value) is 0 Nm. When bypass control ends after overtaking, the parameter MpropMin still limits the torque request to 0 Nm. In this situation, the torque request cannot be set to the actual torque, resulting in significant vibration.

[0044] exist Figure 1In an embodiment of the control method 1000 for a vehicle longitudinal controller (VLC), the VLC may have two or more operating modes, and its operating mode may be determined based on a target acceleration received from an adaptive cruise control (ACC) device. In one embodiment, based on the target acceleration received from the ACC device, the VLC determines that it is in a first operating mode, such as an acceleration control (EC) mode. When the VLC is in the acceleration control (EC) mode, unlike in the prior art, the VLC directly sends a first torque request to the vehicle controller (VCU) without going through a brake energy recovery system (CRBS) or a controlled deceleration unit (CDD) of a driver assistance system. This first torque request may include a torque request value determined based on the target acceleration (positive for acceleration, negative for deceleration) (wherein the torque request value can be positive or negative). That is, in some cases, the VLC may send a first torque request with a negative torque request value to the VCU. In this way, the vehicle longitudinal controller (VLC) not only controls the vehicle's acceleration but also its deceleration (until the VLC's operating state changes, for example, because the maximum regenerative capacity of the vehicle control unit (VCU) cannot meet the current deceleration requirements). Thus, the VLC provides a relatively stable and continuous torque request, thereby helping the vehicle control unit achieve better performance.

[0045] In one embodiment, step S120 may include: receiving a first parameter (e.g., parameter "MPropMin") from the vehicle controller (VCU), the first parameter indicating a minimum adjustable torque value; determining a target torque value based on the target acceleration; and determining that the vehicle longitudinal controller (VLC) is in a first operating mode when the target torque value is greater than or equal to the minimum adjustable torque value. In other embodiments, when the target torque value is less than the minimum adjustable torque value, the vehicle longitudinal controller (VLC) is switched from the first operating mode to a second operating mode, wherein in the second operating mode, the vehicle longitudinal controller (VLC) sends a second torque request to the vehicle controller (VCU) via the brake energy recovery system (CRBS) and the controlled deceleration unit (CDD) of the driver assistance system.

[0046] In one embodiment, both the first torque request and the second torque request are regenerative torque requests. The regenerative torque request may include a negative torque request value, which instructs the motor to reverse for energy recovery. In another embodiment, the first torque request is an acceleration torque request, which includes a positive torque request value.

[0047] In one embodiment, the first operating mode is an acceleration control (EC) mode, and the second operating mode is a deceleration control (DC) mode. Of course, those skilled in the art will understand that other or more operating modes can be set for the vehicle's longitudinal controller according to actual needs.

[0048] In one embodiment, the parameter indicating the minimum adjustable torque value is not obtained from the vehicle controller (VCU). Therefore, in this case, step S120 may include: determining a target torque value based on the target acceleration; determining the maximum regeneration capacity of the vehicle controller (VCU); and determining that the vehicle longitudinal controller (VLC) is in the first operating mode when the target torque value is greater than or equal to the maximum regeneration capacity. That is, since the vehicle controller (VCU) cannot provide information about the parameter (e.g., MPropMin) regarding the minimum adjustable torque value, the maximum regeneration capacity of the vehicle controller (VCU) is considered the minimum adjustable torque value. In this embodiment, when the target torque value is less than the maximum regeneration capacity, the vehicle longitudinal controller (VLC) is switched from the first operating mode to a second operating mode (e.g., from EC mode to DC mode).

[0049] Figure 2 A schematic diagram of a vehicle longitudinal controller (VLC) 2000 according to an embodiment of the present invention is shown. Figure 2 As shown, the vehicle longitudinal controller (VLC) 2000 includes a receiving unit 210, a determining unit 220, and a transmitting unit 230. The receiving unit 210 receives a target acceleration from the adaptive cruise control (ACC) device. The determining unit 220 determines that the VLC is in a first operating mode based on the target acceleration. The transmitting unit 230, in the first operating mode, directly sends a first torque request to the vehicle control unit (VCU) without going through the brake energy recovery system (CRBS) or the controlled deceleration unit (CDD) of the driver assistance system.

[0050] In the context of this invention, the term "vehicle longitudinal controller" (VLC) refers to a device for controlling the longitudinal movement of a vehicle. In one embodiment, the vehicle longitudinal controller (VLC) may be a logic module within the Electronic Stability Program (ESP), specifically a longitudinal control module.

[0051] The term "Controlled Deceleration for Driver Assistance System" (CDD) is also known as driver assistance deceleration control. This controlled deceleration unit typically functions as a lower-level unit of the vehicle's longitudinal controller (VLC). It receives the target acceleration from the VLC and outputs the target braking force to lower-level units (such as the Driver Brake Request Module (DBR) and the Brake Energy Regeneration System (CRBS)) to brake the vehicle.

[0052] Adaptive Cruise Control (ACC) is an intelligent automatic control system. During vehicle operation, a distance sensor (radar) mounted at the front of the vehicle continuously scans the road ahead, while wheel speed sensors collect vehicle speed signals. When the distance to the vehicle ahead is too small, the ACC control unit coordinates with the anti-lock braking system (ABS) and engine control system to apply appropriate braking to the wheels and reduce engine output power, ensuring a safe distance is maintained. When controlling braking, the adaptive cruise control system typically limits deceleration to a level that does not affect comfort. When greater deceleration is required, the ACC control unit issues audible and visual signals to notify the driver to apply the brakes. When the distance to the vehicle ahead increases to a safe level, the ACC control unit controls the vehicle to travel at the set speed. In one or more embodiments of this invention, the aforementioned adaptive cruise control (ACC) device can be an ACC control unit.

[0053] In the context of this invention, the Vehicle Control Unit (VCU), or central control unit of a new energy vehicle, is the core of the entire control system. The VCU collects data such as motor and battery status, accelerator pedal signals, brake pedal signals, actuator and sensor signals, and, after comprehensively analyzing the driver's intentions and making corresponding judgments, monitors the actions of lower-level component controllers. It is responsible for the vehicle's normal operation, brake energy feedback, energy management of the vehicle's engine and power battery, network management, fault diagnosis and handling, and vehicle status monitoring, thereby ensuring the vehicle operates normally and stably with good power performance, high economy, and high reliability. It can be said that the performance of the VCU directly determines the overall performance of the new energy vehicle, playing a pivotal role.

[0054] The Regenerative Braking System (CRBS) recovers excess energy released during braking or coasting, converting it into electricity via a generator and storing it in the battery for subsequent acceleration. This battery also powers in-vehicle electrical devices, reducing reliance on the engine, fuel consumption, and CO2 emissions. Regenerative braking is a crucial technology in modern electric vehicles. In conventional internal combustion engine vehicles, the vehicle's kinetic energy is converted into heat through the braking system and released into the atmosphere during deceleration and braking. In electric or hybrid vehicles, this wasted kinetic energy is converted into electricity and stored in the battery, further converted into driving energy. For example, when starting or accelerating, requiring increased driving force, the electric motor provides auxiliary power to the engine, effectively utilizing electrical energy.

[0055] In one embodiment, the vehicle longitudinal controller (VLC) 2000 may have two or more operating modes, and its operating mode may be determined by the determining unit 220 based on the target acceleration received from the adaptive cruise control (ACC) device. In one embodiment, the determining unit 220 is configured to determine that the vehicle longitudinal controller (VLC) 2000 is in a first operating mode, such as acceleration control (EC) mode, based on the target acceleration received from the adaptive cruise control (ACC) device. When the vehicle longitudinal controller (VLC) is in acceleration control (EC) mode, the transmitting unit 230 of the vehicle longitudinal controller (VLC) 2000 is configured to directly transmit data to the vehicle control unit (VCU). Figure 2 (Not shown) The vehicle longitudinal controller (VLC) sends a first torque request without going through the brake energy recovery system (CRBS) or the controlled deceleration unit (CDD) of the driver assistance system. This first torque request may include a torque request value determined based on the target acceleration (positive for acceleration, negative for deceleration) (where the torque request value can be positive or negative). That is, in some cases, the transmitting unit 230 of the vehicle longitudinal controller (VLC) will send a first torque request with a negative torque request value to the vehicle controller (VCU). In this way, the vehicle longitudinal controller (VLC) 2000 controls not only the vehicle's acceleration but also its deceleration (until the operating state of the vehicle longitudinal controller (VLC) 2000 changes, for example, because the maximum regenerative capacity of the vehicle controller (VCU) cannot meet the current deceleration requirements). Thus, the vehicle longitudinal controller (VLC) 2000 will be able to provide a relatively stable and continuous torque request, thereby helping the vehicle controller achieve better performance.

[0056] In one embodiment, the determining unit 220 is configured to: receive a first parameter from the vehicle controller (VCU), the first parameter indicating a minimum adjustable torque value; determine a target torque value based on the target acceleration; and determine that the vehicle longitudinal controller (VLC) is in the first operating mode when the target torque value is greater than or equal to the minimum adjustable torque value.

[0057] although Figure 2 Not shown in the figure, in one embodiment, the vehicle longitudinal controller VLC 2000 may further include: a first switching unit, used to switch the vehicle longitudinal controller VLC from the first operating mode to a second operating mode when the target torque value is less than the minimum adjustable torque value, wherein in the second operating mode, the vehicle longitudinal controller VLC 2000 sends a second torque request to the vehicle controller VCU via the brake energy recovery system CRBS and the controlled deceleration unit CDD of the driver assistance system.

[0058] In one embodiment, both the first torque request and the second torque request are regenerative torque requests. The regenerative torque request may include a negative torque request value, which instructs the motor to reverse in order to recover energy.

[0059] In another embodiment, the first torque request is an acceleration torque request, which includes a positive torque request value.

[0060] In one or more embodiments, the first operating mode is an acceleration control (EC) mode, and the second operating mode is a deceleration control (DC) mode.

[0061] In one embodiment, the determining unit 220 does not obtain a parameter indicating a minimum adjustable torque value from the vehicle controller (VCU). In this embodiment, the determining unit 220 is configured to: determine a target torque value based on the target acceleration; determine the maximum regenerative capacity of the vehicle controller (VCU); and determine that the vehicle longitudinal controller (VLC) is in the first operating mode when the target torque value is greater than or equal to the maximum regenerative capacity. In this embodiment, the vehicle longitudinal controller (VLC) 2000 may further include: a second switching unit, configured to switch the vehicle longitudinal controller (VLC) 2000 from the first operating mode to a second operating mode when the target torque value is less than the maximum regenerative capacity.

[0062] In one embodiment, the first or second switching unit is configured to determine the switch from acceleration control mode to deceleration control mode based on the parameter "MPropMin" (i.e., the minimum adjustable torque value). Additionally, the parameter "MPropMin" limits the torque request value of the vehicle longitudinal controller (VLC).

[0063] In one embodiment, negative torque requests from the vehicle longitudinal controller VLC 2000 can be filtered using certain limits (values) to ensure the dynamic stability and efficient regenerative performance of the vehicle controller VCU.

[0064] Figure 3 A schematic diagram of a vehicle stability system 3000 according to an embodiment of the present invention is shown. Figure 3 As shown, the vehicle stability system 3000 includes a vehicle longitudinal controller 320, a controlled deceleration unit (CDD) 330, a driver brake request unit (DBR) 340, and a brake energy recovery system (CRBS) 350. The vehicle longitudinal controller 320 is configured to receive a target acceleration from the adaptive cruise control (ACC) unit 310. Based on this target acceleration, the vehicle longitudinal controller 320 determines its operating mode. When the vehicle longitudinal controller 320 is in EC (acceleration control) mode, it sends a first torque request directly to the vehicle control unit (VCU) 360 without going through the brake energy recovery system (CRBS) 350, the driver brake request unit (DBR) 340, or the controlled deceleration unit (CDD) 330 of the driver assistance system.

[0065] When the vehicle longitudinal controller 320 is in DC (Deceleration Control) mode, it is configured to forward the target acceleration to the controlled deceleration unit CDD 330. CDD 330 determines the target braking force based on this target acceleration and sends it to the driver brake request unit DBR 340 for allocation. The driver brake request unit 340 then sends the allocated target regenerative braking force to the brake energy recovery system CRBS 350, which calculates the torque request value and outputs this (negative) torque request value to the vehicle controller 360.

[0066] A conventional controlled deceleration unit (CDD) only uses hydraulic pressure as the starting force (i.e., the requested force) when deceleration control (DC) mode is activated, without considering the current negative torque as part of the braking force. This causes the torque request from the subsequent regenerative braking system (CRBS) to start from 0 Nm. Once the deceleration request exceeds the limits provided by the CRBS, acceleration control (EC) mode must switch to deceleration control (DC) mode.

[0067] In one embodiment of the invention, the controlled deceleration unit CDD 330 is configured to receive a current (negative) torque value and calculate a requested braking force based at least on both the hydraulic pressure and the current (negative) torque value. That is, in order to enable the torque request to begin from the current negative torque, the controlled deceleration unit CDD 330 incorporates the current negative torque as part of the braking force.

[0068] In one embodiment of the invention, the brake energy recovery system CRBS350 is configured to limit the slope of brake fluid replenishment via a second parameter.

[0069] When the starting point of the target braking force (i.e., the requested braking force) is a negative value, the LDM (Latitude Dynamic Management) request from the External Brake Request (EBR) to the Brake Energy Regeneration System (CRBS) will have a step change starting from 0. As a result, the power assist device will generate noise when the Controlled Deceleration Unit (CDD) is activated. This is because when the force requested by the CDD is not starting from 0, it is assumed that the corresponding brake fluid needs to be added instantaneously before the port between the power assist device's reservoir and the master cylinder (i.e., the compensating port) is closed. Therefore, this instantaneous fluid addition will cause significant pressurization noise.

[0070] Therefore, by limiting the slope of parameter EBR_pTargetMC before the compensation port is closed, and using this parameter to control the slope of fluid replenishment, the pressurization can be slowed down, thus solving the NVH problem.

[0071] In summary, one or more embodiments of the present invention eliminate the conflict between the torque requests of the vehicle longitudinal controller (VLC) and regenerative functions (such as CRBS), and the stable and continuous torque requests will help the vehicle controller (VCU) achieve better performance.

[0072] Furthermore, the vehicle longitudinal controller (VLC) in embodiments of the present invention not only controls acceleration but also decelerates before reaching maximum regenerative capacity. In this case, the VLC calculates negative torque during acceleration control. Therefore, the vehicle longitudinal controller (VLC) calculates the torque requested for regeneration until the minimum / minimum torque (negative value) is reached. However, once the minimum / minimum torque is exceeded, the operating mode switches from EC to DC, and then after the CDD determines the target braking force, the CRBS calculates the regenerative torque request.

[0073] In particular, if the driver requests negative torque during the overtaking period of the adaptive cruise control (ACC) (e.g., due to the one-pedal logic), the vehicle control unit (VCU) can correctly determine the overtaking sign because the torque request of the VLC is not limited to 0 Nm.

[0074] Although the foregoing specification describes only some embodiments of the invention, those skilled in the art will understand that the invention can be implemented in many other forms without departing from its spirit and scope. Therefore, the examples and embodiments shown are to be considered illustrative rather than restrictive, and the invention may encompass various modifications and substitutions without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A control method for a vehicle longitudinal controller (VLC), characterized in that, The vehicle longitudinal controller (VLC) is the longitudinal control module in the Electronic Stability Program (ESP). The method includes: Receive target acceleration from the adaptive cruise control (ACC) device; The target torque value is determined based on the target acceleration, and a first parameter indicating the minimum adjustable torque value is received from the vehicle controller (VCU). When the target torque value is greater than or equal to the minimum adjustable torque value, the vehicle longitudinal controller (VLC) is determined to be in acceleration control (EC) mode; and In the acceleration control (EC) mode, a first torque request is sent directly to the vehicle controller (VCU). The first torque request includes a torque request value determined based on the target acceleration. The torque request value can be positive or negative, without going through the brake energy recovery system (CRBS) or the controlled deceleration unit (CDD) of the driver assistance system. The controlled deceleration unit (CDD) is a lower-level unit of the vehicle longitudinal controller (VLC) and is used to receive the target acceleration from the vehicle longitudinal controller (VLC) and output the target braking force to the lower-level unit.

2. The method as described in claim 1, wherein, When the target torque value is less than the minimum adjustable torque value, the vehicle longitudinal controller (VLC) is switched from the acceleration control (EC) mode to the second operating mode. In the second operating mode, the vehicle longitudinal controller (VLC) sends a second torque request to the vehicle controller (VCU) via the brake energy recovery system (CRBS) and the controlled deceleration unit (CDD) of the driver assistance system.

3. The method as described in claim 2, wherein, Both the first torque request and the second torque request are regenerative torque requests.

4. The method of claim 3, wherein, The regenerative torque request includes a negative torque request value, which instructs the motor to reverse in order to recover energy.

5. The method of claim 2, wherein, The second operating mode is deceleration control DC mode.

6. A vehicle longitudinal controller (VLC), characterized in that, The vehicle longitudinal controller (VLC) is the longitudinal control module in the Electronic Stability Program (ESP). The vehicle longitudinal controller (VLC) includes: The receiving unit is used to receive the target acceleration from the adaptive cruise control (ACC) device; The determining unit is configured to determine a target torque value based on the target acceleration, and receive a first parameter indicating a minimum adjustable torque value from the vehicle controller (VCU); when the target torque value is greater than or equal to the minimum adjustable torque value, determine that the vehicle longitudinal controller (VLC) is in acceleration control (EC) mode; and The transmitting unit is configured to directly send a first torque request to the vehicle controller (VCU) in the acceleration control (EC) mode. The first torque request includes a torque request value determined based on the target acceleration. The torque request value can be positive or negative, without going through the brake energy recovery system (CRBS) or the controlled deceleration unit (CDD) of the driver assistance system. The controlled deceleration unit (CDD) is a lower-level unit of the vehicle longitudinal controller (VLC) and is configured to receive the target acceleration from the vehicle longitudinal controller (VLC) and output the target braking force to the lower-level unit.

7. The vehicle longitudinal controller (VLC) as described in claim 6, further comprising: The first switching unit is used to switch the vehicle longitudinal controller (VLC) from the acceleration control (EC) mode to a second operating mode when the target torque value is less than the minimum adjustable torque value. In the second operating mode, the vehicle longitudinal controller (VLC) sends a second torque request to the vehicle controller (VCU) via the brake energy recovery system (CRBS) and the controlled deceleration unit (CDD) of the driver assistance system.

8. The vehicle longitudinal controller (VLC) as described in claim 7, wherein, Both the first torque request and the second torque request are regenerative torque requests.

9. The vehicle longitudinal controller (VLC) as described in claim 8, wherein, The regenerative torque request includes a negative torque request value, which instructs the motor to reverse in order to recover energy.

10. The vehicle longitudinal controller (VLC) as described in claim 7, wherein, The second operating mode is deceleration control DC mode.

11. A computer storage medium, characterized in that, The medium includes instructions that, when executed, perform the control method as described in any one of claims 1 to 5.

12. A vehicle stability system comprising a vehicle longitudinal controller (VLC) as claimed in any one of claims 6 to 10.

13. The vehicle stability system as described in claim 12, further comprising: A controlled deceleration unit (CDD) is configured to receive a current torque value and calculate a requested braking force based at least on both hydraulic pressure and the current torque value.

14. The vehicle stability system as described in claim 12 or 13, further comprising: A brake energy recovery system (CRBS), wherein the brake energy recovery system is configured to limit the slope of replenishing brake fluid via a second parameter.

15. A vehicle comprising a vehicle stability system as claimed in any one of claims 12 to 14.

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