Regenerative Braking Control System and Method for All-Wheel Drive Hybrid Vehicle

Abstract

Provided are a regenerative braking control system and method for an all-wheel drive hybrid vehicle, the hybrid vehicle including a front-wheel HEV (Hybrid Electric Vehicle) powertrain and a rear-wheel EV (Electric Vehicle) powertrain. The control system includes: a manipulation instrument mounted on the steering wheel for performing manual gear shifting and regenerative braking control through the driver's manipulation; and a controller that adjusts the regenerative braking amount and controls the gear shifting mode of each of a front-wheel motor of the front-wheel HEV powertrain and a rear-wheel motor of the rear-wheel EV powertrain by receiving a (-) or (+) switching manipulation signal or a holding manipulation signal from the manipulation instrument.

Description

Technical Field

[0001] The present invention generally relates to a regenerative braking control system and method for an AWD (all-wheel drive) hybrid vehicle. Background Art

[0002] The steering wheels of gasoline and diesel vehicles are equipped with operating instruments for manual shifting.

[0003] As Figure 1 shown, a pair of paddles 10 including a (-) paddle 11 and a (+) paddle 12 can be installed as an example of an operating instrument for manual shifting.

[0004] Therefore, when the (+) paddle 12 on one side of the pair of paddles 10 is operated, the gear position of the automatic transmission is increased through the control signal of the transmission control unit (for example, in the case of a 6-speed transmission, D1 → D2, D2 → D3, D3 → D4, D4 → D5, D5 → D6), and when the (-) paddle 11 on the other side is operated, the gear position of the automatic transmission is decreased through the control signal of the transmission control unit (for example, in the case of a 6-speed transmission, D6 → D5, D5 → D4, D4 → D3, D3 → D2, D2 → D1).

[0005] As Figure 2 shown, a pair of paddles 10 is even installed on the steering wheel of an electric vehicle for deceleration control. When the (+) paddle 12 on one side of the pair of paddles 10 is operated, the deceleration of the motor for driving is controlled to decrease through the control signal of the motor control unit, and when the (-) paddle 11 on the other side is operated, the deceleration of the motor for driving is controlled to increase through the control signal of the motor control unit.

[0006] Figure 3 A power transmission system diagram of a front-wheel drive hybrid vehicle is shown.

[0007] As Figure 3 shown, the power transmission system of a front-wheel drive hybrid vehicle is configured to include: an engine 40 and an electric motor 42, which are directly connected to each other; an engine clutch 41, arranged between the engine 40 and the electric motor 42 to transmit or disconnect engine power; an automatic transmission 43, for shifting gears and outputting power to the drive wheels; an HSG (hybrid starter generator) 44, connected to the crankshaft pulley of the engine to start the engine and supply power to it; and a battery 45, connected to the hybrid starter generator 44 for charging and discharging.

[0008] A front-wheel drive hybrid vehicle may include a control instrument even mounted on its steering wheel, which is used for manual shifting or deceleration control by changing the regenerative braking amount of the electric motor. The control instrument may be configured as a pair of paddles including a (-) paddle and a (+) paddle.

[0009] Therefore, in order to improve the driving convenience of the driver, paddles for manual shifting or deceleration control are installed on internal combustion engine vehicles, electric vehicles, and front-wheel drive hybrid vehicles. However, currently, such paddles are not used for AWD hybrid vehicles.

[0010] Therefore, there is a need for a regenerative braking control system that can more intuitively control the regenerative braking amount of an AWD hybrid vehicle by using a board directly manipulated by the driver. SUMMARY OF THE INVENTION

[0011] The present invention generally relates to a regenerative braking control system and method for an AWD (all-wheel drive) hybrid vehicle. The detailed description relates to a regenerative braking control system and method for an AWD hybrid vehicle, in which the regenerative braking and shifting modes of an AWD hybrid vehicle having a combination of a front-wheel HEV and a rear-wheel EV can be directly controlled by a driver using paddles.

[0012] Embodiments of the present invention have been made in consideration of the problems arising in the prior art, and there is provided a regenerative braking control system and method for an AWD hybrid vehicle, in which the regenerative braking amount of an AWD hybrid vehicle including a front-wheel HEV power transmission system and a rear-wheel EV power transmission system is controlled by a driver directly manipulating paddles according to the driving mode and driving conditions, thereby performing intuitive regenerative braking while continuously decelerating and controlling the front-wheel electric motor and the rear-wheel electric motor.

[0013] According to an embodiment of the present invention, there is a regenerative braking control system for an AWD hybrid vehicle including a front-wheel HEV power transmission system and a rear-wheel EV power transmission system, the system including: a control instrument mounted on the steering wheel for manual shifting and regenerative braking control by the manipulation of a driver; and a controller for adjusting the regenerative braking amount of each of a front-wheel electric motor of the front-wheel HEV power transmission system and a rear-wheel electric motor of the rear-wheel EV power transmission system and controlling the shifting mode by receiving a (-) or (+) switching manipulation signal or a holding manipulation signal of the control instrument.

[0014] The controller may include: an HCU (Hybrid Control Unit) that, after variably setting the torque ratio between the front-wheel motor of the front-wheel HEV powertrain and the rear-wheel motor of the rear-wheel EV powertrain by receiving a (-) or (+) switching manipulation signal or a holding manipulation signal of a manipulation instrument, outputs a torque command signal and a shift mode control signal to adjust the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor; an MCU (Motor Control Unit) that adjusts the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor based on the torque command signal adjusted according to the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor; and a TCU (Transmission Control Unit) that performs shift control of an automatic transmission based on the shift mode control signal.

[0015] Preferably, the manipulation instrument may be configured as a pair of paddles, including a (-) paddle and a (+) paddle capable of performing a switching manipulation or a holding manipulation.

[0016] The regenerative braking control system according to an embodiment of the present invention may further include an APS and a BPS for determining a coasting state of the vehicle, and an off detection signal of the APS and the BPS may be sent to the HCU.

[0017] The regenerative braking control system according to an embodiment of the present invention may further include: a driving mode selection switch for selecting a vehicle driving mode as an eco mode or a sport mode, and a switching signal of the driving mode selection switch is sent to the HCU.

[0018] In addition, when the vehicle is selected to be in a coasting state and its driving mode is selected as the eco mode while receiving a (-) switching manipulation signal or a holding manipulation signal of the manipulation instrument, the HCU may be configured to variably set the torque ratio between the front-wheel motor and the rear-wheel motor, and then output a torque command signal and a shift mode control signal to increase the adjustment of the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor.

[0019] In addition, when the vehicle is selected to be in a coasting state and its driving mode is selected as the eco mode while receiving a (+) switching manipulation signal or a holding manipulation signal of the manipulation device, the HCU may be configured to variably set the torque ratio between the front-wheel motor and the rear-wheel motor, and then output a torque command signal and a shift mode control signal to reduce the adjustment of the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor.

[0020] In addition, when the vehicle is selected to be in a coasting state and its driving mode is selected to be a sport mode, the HCU can be configured to, upon receiving a (-) switching manipulation signal of a manipulation instrument, send a lower gear transmission command signal of a gear lower than the current gear position to the TCU, and the HCU can be configured to, upon receiving a (+) switching manipulation signal of the manipulation instrument, send a higher gear transmission command signal of a gear higher than the current gear position to the TCU.

[0021] Preferably, the regenerative braking control system according to an embodiment of the present invention may further include: an AHB (active hydraulic booster) configured to receive a cooperative control signal, configured to distribute total braking force from the HCU when a driver presses a brake pedal, and configured to generate hydraulic braking pressure of a hydraulic braking system in addition to regenerative braking force of an electric motor.

[0022] According to another embodiment of the present invention, there is provided a regenerative braking control method for an AWD hybrid vehicle including a front-wheel HEV power transmission system and a rear-wheel EV power transmission system, the control method including: determining in a controller whether the vehicle is in a coasting state or a current driving mode; when it is determined in the controller that the vehicle is in a coasting state and its driving mode is an eco mode, changing a function of a manipulation instrument to a function of adjusting a regenerative braking amount; and when the controller receives a (-) or (+) switching manipulation signal or a hold manipulation signal of the manipulation instrument, adjusting the regenerative braking amount and controlling a gearshift mode of each of a front-wheel motor of the front-wheel HEV power transmission system and a rear-wheel motor of the rear-wheel EV power transmission system.

[0023] When adjusting the regenerative braking amount and controlling the gearshift mode, the HCU of the controller can variably set a torque ratio between the front-wheel motor of the front-wheel HEV power transmission system and the rear-wheel motor of the rear-wheel EV power transmission system, and then output a torque command signal for adjusting the regenerative braking amount of the front-wheel motor and the rear-wheel motor and a gearshift mode control signal.

[0024] Preferably, when the HCU of the controller receives signals of a vehicle speed sensor, an APS (accelerator position sensor), and a BPS (brake position sensor), when the vehicle speed is higher than 0 KPH and the APS is turned off and the BPS is turned off, it can be determined that the vehicle is in a coasting state.

[0025] After determining whether a first manipulation signal for performing a (-) manipulation of the manipulation instrument is an initial single switching input signal or a single hold input signal, when it is determined that the first manipulation signal is an initial single switching input signal, the HCU of the controller can set a target deceleration of the vehicle speed and set a variable torque ratio between the front-wheel motor and the rear-wheel motor to a target torque ratio that satisfies the target deceleration.

[0026] Preferably, when the HCU receives an additional primary switching input signal for continuously performing the (-) operation of the operating instrument within a predetermined time after receiving the initial primary switching input signal, each time the additional primary switching input signal is received, control is executed to increase the regenerative braking torque of the front-wheel motor and the rear-wheel motor to a predetermined level; and speed change control can be executed based on the preset speed change mode of the front wheels to increase the deceleration.

[0027] In addition, when it is determined that the first operation signal for the (-) operation of the operating instrument is an initial primary switching input signal or a primary hold input signal, and then it is determined that the first operation signal is a primary hold input signal, the HCU of the controller sets the target deceleration of the vehicle speed and sets the variable torque ratio between the front-wheel motor and the rear-wheel motor to a target torque ratio that satisfies the target deceleration.

[0028] Preferably, after receiving the primary hold input signal as the first operation signal for performing the (-) operation of the operating instrument in the HCU of the controller, control can be executed to increase the regenerative braking torque of the front-wheel motor to the maximum regenerative braking torque, control to increase the regenerative braking torque of the rear-wheel motor to a predetermined level, and speed change control based on the preset speed change mode for the front wheels to increase the deceleration.

[0029] When it is determined that the second operation signal for performing the (+) operation of the operating instrument is an initial primary switching input signal or a primary hold input signal, and then it is determined that the second operation signal is an initial primary switching input signal, the HCU of the controller can set the release of the target deceleration of the vehicle speed and set the torque ratio between the front-wheel motor and the rear-wheel motor to the torque ratio for the release of the target deceleration.

[0030] When the HCU receives an additional primary switching input signal for continuously performing the (+) operation of the operating instrument within a predetermined time after receiving the initial primary switching input signal, each time the additional primary switching input signal is received, control can be executed to reduce the regenerative braking torque of the front-wheel motor to a predetermined level, and speed change control can be executed based on the preset speed change mode for the front wheels to reduce the deceleration.

[0031] In addition, when it is determined that the second operation signal for performing the (+) operation of the operating instrument is a primary hold input signal, the HCU of the controller can set the release of the target deceleration of the vehicle speed and set the torque ratio between the front-wheel motor and the rear-wheel motor to the torque ratio for the release of the target deceleration.

[0032] Preferably, when a hold input signal is received in the HCU of the controller as a second manipulation signal for the (+) manipulation of the instrument, control for reducing the regenerative braking torque of the front-wheel motor to a reference regenerative braking torque can be executed, and shift control can be executed based on a shift pattern preset for the front wheels to reduce the deceleration.

[0033] Meanwhile, when it is determined that the current driving mode is the sport mode, the HCU of the controller can change the function of the instrument to a shift gear adjustment function of the transmission, such that when a first manipulation signal for (-) switching manipulation is received, control for reducing the shift gear can be executed, and when a second manipulation signal for (+) switching manipulation is received, control for increasing the shift gear can be executed.

[0034] In addition, when the (-) manipulation of the instrument is held for a predetermined time or more, the motor torque can be limited to the maximum regenerative braking torque, and braking cooperative control can be performed through the AHB (Active Hydraulic Booster) or EPB (Electric Parking Brake System) to generate a hydraulic braking force.

[0035] Furthermore, when the ABS or TCS operates during driving in a regenerative braking operation, when shifting to the N gear during driving in a regenerative braking operation, the regenerative braking of the front-wheel motor and the rear-wheel motor can be stopped, and when returning from the N gear to the D gear and when the operation of the ABS or TCS is released, the regenerative braking of the front-wheel motor and the rear-wheel motor can be performed with the previous regenerative braking amount.

[0036] Embodiments of the present invention provide the following effects through the above problem-solving means.

[0037] First, in an AWD hybrid vehicle having a combination of a front-wheel HEV and a rear-wheel EV, the torque and shift pattern of the front-wheel motor are controlled by the driver's paddle manipulation to control the front-wheel deceleration, and at the same time, the torque of the rear-wheel motor is controlled by the driver's paddle manipulation to control the rear-wheel deceleration. Therefore, the optimal regenerative braking energy can be recovered, and the fuel efficiency can be improved.

[0038] Second, regenerative braking can be performed through the switching manipulation of the paddle, and regenerative braking can be performed through the holding manipulation of the paddle. Therefore, more intuitive regenerative braking can be performed.

[0039] Third, in a sport driving mode, manual shifting is performed by the driver's paddle manipulation, and in an eco-driving mode, regenerative braking is performed by the driver's paddle manipulation, thereby improving the driving convenience of the driver and increasing the fuel efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] With reference to the accompanying drawings, the above and other objects, features and other advantages of the embodiments of the present invention will be more clearly understood from the following detailed description, wherein:

[0041] Figure 1 is a diagram showing an example in which paddles for manual shifting are provided on the steering wheel of an internal combustion engine vehicle;

[0042] Figure 2 is a diagram showing an example in which paddles for deceleration adjustment are provided on the steering wheel of an electric vehicle;

[0043] Figure 3 is a schematic diagram of power transmission of a front-wheel hybrid vehicle;

[0044] Figure 4 is a schematic diagram of power transmission of an AWD hybrid vehicle to which a regenerative braking control system according to an embodiment of the present invention is applied;

[0045] Figure 5 is a block diagram showing a regenerative braking control system of an AWD hybrid vehicle according to an embodiment of the present invention;

[0046] Figure 6 、 Figure 7 、 Figure 8 is a flowchart showing a regenerative braking control method of an AWD hybrid vehicle according to an embodiment of the present invention; and

[0047] Figure 9 is a graph showing a regenerative braking control process of an AWD hybrid vehicle according to an embodiment of the present invention. Detailed Embodiments

[0048] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0049] Figure 4 is a schematic diagram of power transmission of an AWD hybrid vehicle to which a regenerative braking control system according to an embodiment of the present invention is applied, and shows an example of an AWD (all-wheel drive) system having a combination of a front-wheel HEV (hybrid electric vehicle) power transmission system and a rear-wheel EV (electric vehicle) power transmission system.

[0050] The front-wheel HEV power transmission system includes: an engine 110 and a front-wheel motor 130, which are directly connected to each other; an engine clutch 120, arranged between the engine 110 and the front-wheel motor 130 to transmit or disconnect engine power; an automatic transmission 140, which outputs power to the front wheels by switching the power; an HSG 150 (hybrid starter generator), connected to the crankshaft pulley of the engine to start the engine and provide power for it; and a battery 160, connected to the front-wheel motor 130 and the HSG 150 for charging and discharging.

[0051] The rear-wheel EV power transmission system is configured to include: a rear-wheel motor 170, connected to the battery 160 for charging and discharging; and a reduction gear 180, which reduces the power of the rear-wheel motor 170 to output power to the rear wheels.

[0052] According to an embodiment of the present invention, in an AWD hybrid vehicle having the above-described combination of a front-wheel HEV and a rear-wheel EV, the front-wheel deceleration is controlled by controlling the torque and shift mode of the front-wheel motor through the driver's paddle operation, and at the same time, the rear-wheel deceleration is controlled by controlling the torque of the rear-wheel motor through the driver's paddle operation, so that the optimal regenerative braking energy can be recovered, and more intuitive regenerative braking can be performed.

[0053] Figure 5 It is a block diagram showing a regenerative braking control system and a shift control system of an AWD hybrid vehicle according to an embodiment of the present invention.

[0054] A manipulation instrument that can be directly manipulated by the driver is installed on the steering wheel of an AWD hybrid vehicle for manual shifting and regenerative braking control.

[0055] For example, as a manipulation instrument for manual shifting and regenerative braking control, a pair of paddles 210 can be installed on the steering wheel 200 of an AWD hybrid vehicle, and the pair of paddles 210 includes a (-) paddle 212 and a (+) paddle 214.

[0056] Hereinafter, for the purpose of helping to understand the present invention, the (-) paddle 212 and the (+) paddle 214 as manipulation instruments will be described as examples.

[0057] The manipulation signal of the (-) paddle 212 or the manipulation signal of the (+) paddle 214 of the pair of paddles 210 is input to the HCU (hybrid control unit) 220, which is the advanced controller of the AWD hybrid vehicle.

[0058] In addition, a driving mode selection switch 202 installed near the driver's seat is connected to the HCU 220 to determine whether the current vehicle driving mode is an eco mode or a sport mode.

[0059] Therefore, the HCU 220 can determine whether the current driving mode is an eco mode or a sport mode based on the switching signal received from the driving mode selection switch 202.

[0060] In addition, in order to determine whether the current driving mode is in a coasting state, the detection signal of the APS (accelerator position sensor) 206 that is turned on when the accelerator pedal is pressed and turned off when the accelerator pedal is not pressed, and the detection signal of the BPS (brake position sensor) 208 that is turned on when the brake pedal is pressed and turned off when the brake pedal is not pressed, are input to the HCU 220.

[0061] Preferably, the manipulation signal of the paddle 210 and the switching signal of the driving mode selection switch 202 can be sent to the HCU 220 via the TCU (transmission control unit) 240.

[0062] Refer to Figure 5 , when, after the current driving mode is determined to be the eco mode, a switching or holding manipulation signal of the (-) paddle 212 of the driver is received to increase the deceleration, the HCU 220 variably sets the torque ratio between the front-wheel motor and the front-wheel motor including the vehicle deceleration, and outputs a signal for increasing the regenerative braking amount for controlling each of the front-wheel motor and the rear-wheel motor and a shift mode control signal.

[0063] More specifically, when the driver performs a switching or holding manipulation of the (-) paddle 212 to increase the deceleration and the regenerative braking amount after the current driving mode is determined to be the eco mode, the HCU 220 sets a target deceleration of the vehicle speed based on the manipulation signal, sets a variable torque ratio between the front-wheel motor and the rear-wheel motor to a target torque ratio that satisfies the target deceleration, sends a torque command signal for increasing the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor to the MCU 230 (motor control unit), and sends a command signal for controlling the shift mode to the TCU 240.

[0064] Conversely, when, after the current driving mode is determined to be the eco mode, the driver receives a switching or holding manipulation signal of the (+) paddle 214 for reducing the deceleration, the HCU 220 variably sets the torque ratio between the front-wheel motor and the rear-wheel motor including the vehicle deceleration, and outputs a signal for reducing the regenerative braking amount for controlling each of the front-wheel motor and the rear-wheel motor and a shift mode control signal.

[0065] More specifically, when, after determining that the current driving mode is the eco-friendly mode, the driver performs a switching operation or a holding operation of the (+) paddle 214 for reducing the deceleration and the amount of regenerative braking, the HCU 220 sets the target deceleration of the vehicle speed based on the operation signal, sets the torque ratio between the front-wheel motor and the rear-wheel motor to a target torque ratio that satisfies the target deceleration, sends a torque command signal for reducing the amount of regenerative braking in each of the front-wheel motor and the rear-wheel motor to the MCU 230, and sends a command signal for transmission mode control to the TCU 240.

[0066] In this case, the MCU 230 controls the amount of regenerative braking in each of the front-wheel motor and the rear-wheel motor based on the torque command signal for regenerative braking amount control of the front-wheel motor and the rear-wheel motor sent from the HCU 220, and the TCU 240 performs shift control of the automatic transmission based on the shift mode control signal sent from the HCU 220.

[0067] Refer to Figure 5 , when the current driving mode is determined to be in the sport mode, the HCU 220 does not perceive the operation function of the paddle 210 as a function of adjusting the amount of regenerative braking, but as a function of manually controlling the shift gear of the transmission.

[0068] Therefore, when the driver receives an operation signal of the (-) paddle 212 after the current driving mode is determined to be the sport mode, the HCU 220 sends a shift command signal of a shift gear lower than the current shift gear to the TCU 240. Therefore, a lower gear shift can be performed according to the manual operation of the driver on the (-) paddle 212.

[0069] On the contrary, when the driver receives an operation signal of the (+) paddle 214 after the current driving mode is determined to be the sport mode, the HCU 220 sends a shift command signal of a shift gear higher than the current shift gear to the TCU 240. Therefore, a higher gear shift can be performed according to the manual operation of the driver on the (+) paddle 214.

[0070] Meanwhile, in Figure 5 the reference numeral 250 denotes an AHB (Active Hydraulic Booster) 250 that generates hydraulic braking force.

[0071] When the driver presses the brake pedal and performs the function of the hydraulic braking pressure of the hydraulic braking system in addition to the regenerative braking force of the motor, the AHB 250 receives a cooperative control signal for distributing the total braking force from the HCU 220.

[0072] Hereinafter, a regenerative braking control method according to an embodiment of the present invention based on the above configuration will be described.

[0073] Figure 6 , Figure 7 , Figure 8 is a flowchart showing a regenerative braking control method for an AWD hybrid vehicle according to an embodiment of the present invention.

[0074] First, in S101, in the HCU220 which is the high-level controller of the AWD hybrid vehicle, it is determined whether the vehicle is in a coasting state.

[0075] For example, the HCU 220 receives signals from the vehicle speed sensor 204, the APS 206, and the BPS 208. When the vehicle speed is higher than 0 KPH, the APS is off (the accelerator pedal is not pressed), and the BPS is off (the brake pedal is not pressed), it is determined that the vehicle is in a coasting state.

[0076] Next, in S102, the HCU 220 determines the current driving mode.

[0077] That is, in S103, the HCU 220 determines whether the current driving mode is selected as the eco mode based on the switching signal received from the driving mode selection switch 202 installed near the driver's seat.

[0078] When the current driving mode is determined to be the eco mode in the HCU 220, after changing the function of the pair of paddles 210 including the (-) paddle 212 and the (+) paddle 214 to the function of adjusting the regenerative braking amount, in S104, it is determined whether the driver has received the first manipulation signal of the (-) paddle 212 or the second manipulation signal of the (+) paddle 214 of the pair of paddles 210.

[0079] As a result of the determination in step S104, when it is determined that the first manipulation signal of the (-) paddle 212 is received, in S105, it is determined whether the first manipulation signal is an initial one-time toggling input signal or a one-time hold input signal.

[0080] For reference, toggling refers to a single-touch manipulation of flipping or pressing the paddle for less than a predetermined time, and holding refers to a manipulation of flipping or pressing the paddle for more than a predetermined time.

[0081] As a result of the determination in step S105, when the first manipulation signal of the (-) paddle 212 is determined to be an initial one-time toggling input signal in S106, in S107 the HCU 220 sets the target deceleration for the vehicle speed for stopping, and sets the torque ratio between the front-wheel motor and the rear-wheel motor to the target torque ratio that satisfies the target deceleration.

[0082] In S108, when the HCU 220 receives an additional single-operation signal for continuous operation of the (-) paddle 212 (i.e., an additional single-switching input signal within a predetermined time after receiving the initial single-switching input signal), each time the additional single-switching input signal is received, control is executed to increase the regenerative braking torque of the front-wheel motor to a predetermined level, and at the same time, the TCU 240 performs shift control based on the shift pattern preset for the front wheels according to the command of the HCU 220 to increase the deceleration.

[0083] In addition, each time the additional single-switching input signal is received, the HCU 220 executes control to increase the regenerative braking torque of the rear-wheel motor to a predetermined level. In this case, in S109, the regenerative braking torque of the rear-wheel motor is maintained at the target torque ratio between the front-wheel motor and the rear-wheel motor set in step S107.

[0084] That is, each time the additional single-switching input signal is received, the HCU 220 executes control to increase the regenerative braking torque of the rear-wheel motor to a predetermined level to increase the deceleration. In step S107, the target torque ratio between the front-wheel motor and the rear-wheel motor is set, so the increase level of the regenerative braking torque of the rear-wheel motor is within the target torque ratio.

[0085] As a result of the determination in step S105, when the first operation signal of the (-) paddle 212 is determined to be a single-hold input signal, in S110, the HCU 220 sets the target deceleration of the vehicle speed for vehicle stop and sets the variable torque ratio of the front-wheel motor and the rear-wheel motor to the target torque ratio that satisfies the target deceleration.

[0086] Next, the single-hold input signal is a signal based on the driver operating the paddle for a predetermined time or more. Therefore, in S111, the HCU 220 executes control to increase the regenerative braking torque of the front-wheel motor to the maximum regenerative braking torque, and at the same time, performs shift control based on the shift pattern preset for the front wheels to increase the deceleration.

[0087] That is, when the HCU 220 sends a command to increase the regenerative braking torque of the front-wheel motor to the maximum regenerative braking torque to the MCU 230, the regenerative braking torque of the front-wheel motor is controlled to the maximum regenerative braking torque through the control of the MCU 230, and at the same time, the TCU 240 performs shift control based on the shift pattern preset for the front wheels according to the command of the HCU 220 to increase the deceleration.

[0088] In addition, when it is determined that the first manipulation signal of the (-) paddle 212 is a one-time hold input signal, the HCU 220 executes control to increase the regenerative braking torque of the rear-wheel motor to a predetermined level. In this case, in S112, the regenerative braking torque of the rear-wheel motor is maintained at the target torque ratio between the front-wheel motor and the rear-wheel motor set in step S110.

[0089] That is, when it is determined that the first manipulation signal of the (-) paddle 212 is a one-time hold input signal, the HCU 220 executes control to increase the regenerative braking torque of the rear-wheel motor to increase the deceleration to a predetermined level. In step S110, since the target torque ratio between the front-wheel motor and the rear-wheel motor is set, the level of increasing the regenerative braking torque of the rear-wheel motor is within the range of the target torque ratio.

[0090] In this case, the MCU 230 can execute control to increase the regenerative braking torques of the front-wheel motor and the rear-wheel motor to a predetermined level, and control to increase the regenerative braking torque of the front-wheel motor to the maximum regenerative braking torque, according to the command signal sent by the HCU 220. The TCU 240 can execute shift control based on the shift pattern preset for increasing the deceleration, according to the command signal sent by the HCU 220.

[0091] Meanwhile, as a result of the determination in step S104, when it is determined that the first manipulation signal of the (-) paddle 212 is not received, it is determined in S113 whether the second manipulation signal of the (+) paddle 214 is received.

[0092] As a result of the determination in step S113, when it is determined that the second manipulation signal of the (+) paddle 214 has been received in the HCU 220, in S114, it is determined whether the second manipulation signal is an initial one-time switching input signal or a one-time hold input signal.

[0093] As a result of the determination in step S114, when the second manipulation signal of the (+) paddle 214 is determined to be an initial one-time switching input signal in S115, in S116, the HCU 220 releases by setting the target deceleration of the vehicle speed for stopping, and sets the variable torque ratio between the front-wheel motor and the rear-wheel motor to the torque ratio for target deceleration release.

[0094] When the HCU 220 receives an additional second manipulation signal for continuously manipulating the (+) paddle 214 (i.e., an additional single-switch input signal within a predetermined time after receiving the initial single-switch input signal), in S117, whenever the additional single-switch input signal is received, control is executed to reduce the regenerative braking torque of the front-wheel motor to a predetermined level, and at the same time, shift control is performed based on the shift pattern preset for the front wheels to reduce the deceleration.

[0095] In addition, whenever the additional single-switch input signal is received, the HCU 220 executes control to reduce the regenerative braking torque of the rear-wheel motor to a predetermined level. In this case, in S118, the regenerative braking torque of the rear wheels is maintained at the torque ratio between the front-wheel motor and the rear-wheel motor set in step S116.

[0096] As a result of the determination in step S114, when it is determined that the second manipulation signal of the (+) paddle 214 is a single-hold input signal, in S119, the HCU 220 releases by setting the target deceleration of the vehicle speed for stopping, and sets the torque ratio between the front-wheel motor and the rear-wheel motor to the torque ratio for target deceleration release.

[0097] Next, the single-hold input signal is a signal in which the driver manipulates the paddle for a predetermined time or more. Therefore, in S120, the HCU 220 executes control to reduce the regenerative braking torque of the front-wheel motor to the reference regenerative braking torque (basic motor regenerative braking amount), and at the same time, shift control is performed based on the shift pattern preset for the front wheels to reduce the deceleration.

[0098] In addition, when it is determined that the second manipulation signal of the (+) paddle 214 is a single-hold input signal, the HCU 220 executes control to reduce the regenerative braking torque of the rear-wheel motor to the reference regenerative braking torque. In this case, in S121, the regenerative braking torque of the rear-wheel motor is maintained at the torque ratio between the front-wheel motor and the rear-wheel motor set in step S119.

[0099] In this case, the MCU 230 can execute control to reduce the regenerative braking torque of the front-wheel motor and the rear-wheel motor to a predetermined level, and control to reduce the regenerative braking torque of the front-wheel motor and the rear-wheel motor to the reference regenerative braking torque, according to the command signal sent by the HCU 220. The TCU 240 can execute shift control based on the shift pattern preset for reducing the deceleration, according to the command signal sent by the HCU 220.

[0100] Meanwhile, as a result of the determination in step S103, when the driving mode selection switch 202 installed near the driver's seat is not selected to be in the eco mode but is changed from the eco mode to the sport mode, or when the eco mode is turned off, in S123, the HCU 220 changes the function of the paddle 210 to the gear shift adjustment function of the transmission.

[0101] Therefore, in order to determine whether the gear shift of the transmission is controlled, in S124, the HCU 220 determines whether it has received the first manipulation signal of the switching manipulation of the (-) paddle 212 in the pair of paddles 210, or in S125, determines whether it has received the second manipulation signal of the switching manipulation of the (+) paddle 214.

[0102] As a result of the determination in step S124, when it is determined that the first manipulation signal of the (-) paddle 212 has been received, in S126, the HCU 220 performs the control for reducing the gear shift.

[0103] On the contrary, as a result of the determination in step S125, when it is determined that the second manipulation signal of the switching manipulation for the (+) paddle 214 has been received, in S127, the HCU 220 performs the control for increasing the gear shift.

[0104] Of course, the TCU 240 can perform the reduction or increase of the gear shift according to the command signal sent by the HCU 220.

[0105] Meanwhile, after performing steps S109, S112, S118, and S121, or as a result of the determination in step S113, when it is determined that the second manipulation signal of the (+) paddle 214 has not been received, in S122, it is determined whether a function change release signal for the paddle 210 (for example, the manipulation signal for changing the driving mode selection switch 202 from the eco mode to the sport mode, or the manipulation signal for turning off the driving mode selection switch) has been received in the HCU 220.

[0106] As a result of the determination in step S122, when it is determined that the function change release signal has been received, in S123, the HCU220 changes the function of the paddle 210 to the gear shift adjustment function of the transmission, and repeats the execution of steps S124 to S127.

[0107] Therefore, in an AWD hybrid vehicle, the torque of the front-wheel motor and the gear shift mode are controlled by the driver's paddle manipulation, thereby controlling the front-wheel deceleration. At the same time, the torque of the rear-wheel motor is controlled by the driver's paddle manipulation, thereby controlling the rear-wheel deceleration. Therefore, the optimal regenerative braking energy can be recovered. In addition, the regenerative braking is performed by the driver's switching manipulation and holding manipulation of the paddle, so more intuitive regenerative braking can be achieved.

[0108] Herein, the regenerative braking control process of an AWD hybrid vehicle according to an embodiment of the present invention will be described in more detail with reference to an embodiment.

[0109] Figure 9 is a graph showing the regenerative braking control process of an AWD hybrid vehicle according to an embodiment of the present invention.

[0110] Basic motor regenerative braking amount

[0111] At Figure 9 In, reference numeral ① represents the closing operation of the APS 206.

[0112] When the driver releases the accelerator pedal, as shown in ①-1 of Figure 9 the regenerative braking amount of the AWD hybrid vehicle is adjusted to the basic motor regenerative braking amount (coasting regeneration).

[0113] More specifically, a closing signal of the APS 206 is sent to the HCU 220, the HCU 220 sends a torque command signal for the basic motor regenerative braking amount to the MCU 230, and the MCU 230 controls the motor torque with the basic motor regenerative braking amount.

[0114] Preferably, the basic motor regenerative braking amount can only be obtained by controlling the regenerative braking torque of the front-wheel motor.

[0115] In this case, as described above, when it is determined that the vehicle is in a coasting state (for example, when the vehicle speed is greater than 0 KPH, during the downhill driving of the vehicle, the APS is closed and the BPS is closed), the HCU 220 variably sets the torque ratio between the front-wheel motor included in the front-wheel HEV powertrain and the rear-wheel motor included in the rear-wheel EV powertrain (for example, front-wheel motor 7: rear-wheel motor 3).

[0116] For example, as described above, after the current driving mode is determined to be the eco mode, when the driver receives a switching or holding operation signal of the (-) paddle 212 for increasing the deceleration, the HCU 220 variably sets the torque ratio between the front-wheel motor and the rear-wheel motor including the vehicle deceleration. On the contrary, when the second operation signal of the (+) paddle 214 is received, the HCU 220 releases the target deceleration of the vehicle speed and sets the variable torque ratio between the front-wheel motor and the rear-wheel motor to the torque ratio for the release of the target deceleration.

[0117] Of course, when a specific situation such as operating the paddle 210 to control the deceleration and the amount of regenerative braking occurs, the torque ratio between the front-wheel motor and the rear-wheel motor is variably controlled. Therefore, it is possible to variably control the motor torque in the range from front-wheel motor 0%: rear-wheel motor 100% to front-wheel motor 100%: rear-wheel motor 0%.

[0118] Deceleration control when switching the (-) paddle

[0119] In Figure 9 the reference numeral ② represents the time of the switching operation of the (-) paddle 212, that is, the time when the driver switches the (-) paddle 212 for deceleration.

[0120] Therefore, as Figure 9 shown in ②-1, during the first switching operation of the (-) paddle 212, in addition to the basic motor regenerative braking amount, a first additional regenerative braking amount (coasting regeneration TQ 1) is applied to the motor to increase the deceleration.

[0121] In addition, as Figure 9 shown in ②-2, during the second switching operation of the (-) paddle 212 (during the additional switching operation), in addition to the first additional regenerative braking amount (coasting regeneration TQ 1), a second additional regenerative braking amount (coasting regeneration TQ 2) is applied to the motor to further increase the deceleration.

[0122] In addition, as Figure 9 shown in ②-3, during the third switching operation of the (-) paddle 212 (during the two additional switching operations), in addition to the second additional regenerative braking amount (coasting regeneration TQ 2), a third additional regenerative braking amount (coasting regeneration TQ 3) is applied to the motor to further increase the deceleration.

[0123] In this case, in addition to the basic motor regenerative braking amount, an additional regenerative braking amount can be obtained by controlling the regenerative braking torque of the front-wheel motor and the rear-wheel motor. As described above, the deceleration amount (②-1, ②-2, ②-3) can be variably determined by operating the (-) paddle, and at the same time, the torque ratio between the front-wheel motor included in the front-wheel HEV powertrain and the rear-wheel motor included in the rear-wheel EV powertrain can be variably set (for example, front-wheel motor 7: rear-wheel motor 3).

[0124] Deceleration control when holding the (-) paddle

[0125] In Figure 9 the reference numeral ③ represents the starting point of the holding operation of the (-) paddle 212 for deceleration, and the reference numeral ④ represents the ending point of the holding operation of the (-) paddle 212 for deceleration.

[0126] As described above, in case of a maintained manipulation of the (-) paddle (e.g., a pressing manipulation of the paddle is performed for several seconds), the HCU 220 sends a torque command signal for a maximum motor regenerative braking amount to the MCU 230, and thus the motor torque is controlled by the MCU 230 at the maximum motor regenerative braking amount.

[0127] Therefore, if Figure 9 As described with reference mark ③-1, when the (-) paddle 212 is kept operated, the maximum target deceleration is generated by the maximum regenerative braking torque.

[0128] In addition, the motor Figure 9 When the basic motor regenerative braking amount (coasting regeneration) shown in ①-1 is operated, the motor torque increases to Figure 9 ③-1 represents the maximum regenerative braking torque (paddle regeneration TQ), while increasing the deceleration to the maximum target deceleration.

[0129] In addition, the motor Figure 9 When the first additional regenerative braking amount (coasting regeneration TQ 1) shown in ②-1 is operated, the motor torque is also controlled to increase to 0.0015mm while the (-) paddle 212 is kept operated. Figure 9 The maximum regenerative braking torque shown in ③-1 is obtained, and the deceleration is increased to the maximum target deceleration.

[0130] In addition, the motor Figure 9 When the second additional regenerative braking amount (coasting regeneration TQ 2) shown in ②-2 is operated, the motor torque is also controlled to increase to Figure 9 The maximum regenerative braking torque shown in ③-1 is obtained, while the deceleration is controlled to increase to the maximum target deceleration.

[0131] In addition, the motor Figure 9 When the third additional regenerative braking amount (coasting regeneration TQ 3) shown in ②-3 is operated, the motor torque is also controlled to increase to 0.0015mm while the (-) paddle 212 is kept operated. Figure 9 The maximum regenerative braking torque shown in ③-1 is obtained, and at the same time, the deceleration is controlled to increase to the maximum target deceleration.

[0132] In this case, when the HCU 220 receives a signal that the driver holds the (-) paddle 212 to increase the deceleration, the HCU 220 variably sets the torque ratio between the front-wheel motor and the rear-wheel motor including the vehicle deceleration, sends a command signal for increasing the regenerative braking force of the front-wheel motor and the rear-wheel motor to the MCU 230, and sends a command signal for shift mode control to the TCU 240.

[0133] Therefore, as described above, the deceleration increase control according to the hold operation of the (-) paddle and the shift control for deceleration increase through the Figure 9 preset shift mode ⑦ are executed simultaneously, so that the vehicle deceleration can be easily increased to the maximum target deceleration.

[0134] Deceleration control when switching the (+) paddle

[0135] When switching the (+) paddle 214, the HCU 220 variably sets the torque ratio between the front-wheel motor and the rear-wheel motor including the vehicle deceleration, outputs a signal for reducing the regenerative braking force of the front-wheel motor and the rear-wheel motor to the MCU 230, and outputs a shift mode control signal to the TCU 240, thereby controlling the deceleration to gradually decrease.

[0136] For example, as shown in ②-3 of Figure 9 , through the switching operation of the (-) paddle 212, the deceleration is controlled to increase to the third additional regenerative braking amount (coasting regenerative TQ 3), and when the switching operation of the (+) paddle 214 is continuously executed twice, the Figure 9 third additional regenerative braking amount (coasting regenerative TQ 3) represented by ②-3 is adjusted in the order of the second additional regenerative braking amount (coasting regenerative TQ 2) shown in ②-2 of Figure 9 and the first additional regenerative braking amount (coasting regenerative TQ 1) shown in ②-1 of Figure 9 .

[0137] Deceleration control when holding the (+) paddle

[0138] In Figure 9 , the reference numeral ⑤ indicates the time when the hold operation of the (+) paddle 214 is executed.

[0139] Accordingly, when the holding operation of the (+) paddle 214 is performed, the HCU 220 variably sets the torque ratio between the front-wheel motor and the rear-wheel motor including the vehicle deceleration, outputs a signal for reducing the regenerative braking force for the front-wheel motor and the rear-wheel motor to the MCU 230, and outputs a shift mode control signal to the TCU 240. Accordingly, the motor torque is controlled by the basic motor regenerative braking amount, and thus the deceleration is controlled to be reduced to the level of the basic motor regenerative braking amount.

[0140] That is, in the case of the holding operation of the (+) paddle 214, the motor torque is reduced to the predetermined deceleration slope indicated by ⑤-1 of Figure 9 and is controlled to return to the basic motor regenerative braking amount (coasting regeneration) shown by ①-1 of Figure 9 .

[0141] For example, when the motor is operating at the maximum regenerative braking torque (paddle regeneration TQ), in the case of the holding operation of the (+) paddle 214, the motor torque is controlled to return to the basic motor regenerative braking amount (coasting regeneration) indicated by ①-1 of Figure 9 .

[0142] In addition, when the motor is operating at the third additional regenerative braking amount (coasting regeneration TQ 3), in the case of the holding operation of the (+) paddle 214, the motor torque is similarly controlled to return to the basic motor regenerative braking amount (coasting regeneration) shown by ①-1 of Figure 9 .

[0143] In addition, when the motor is operating at the second additional regenerative braking amount (coasting regeneration TQ 2), in the case of the holding operation of the (+) paddle 214, the motor torque is similarly controlled to return to the basic motor regenerative braking amount (coasting regeneration) indicated by ①-1 of Figure 9 .

[0144] In addition, when the motor is operating at the first additional regenerative braking amount (coasting regeneration TQ 1), in the case of the holding operation of the (+) paddle 214, the motor torque is similarly controlled to return to the basic motor regenerative braking amount (coasting regeneration) indicated by ①-1 of Figure 9 .

[0145] Stop the vehicle by holding the (-) paddle

[0146] When the holding operation of the (-) paddle is performed for a predetermined time or more, the HCU 220 variably sets the torque ratio between the front-wheel motor and the rear-wheel motor including the vehicle deceleration, sets the torque ratio to first reduce the torque of the rear-wheel motor and gradually reduce the torque of the front-wheel motor, and outputs a signal for reducing the regenerative braking force of the front-wheel motor and the rear-wheel motor and for vehicle stop to the MCU 230.

[0147] Therefore, in Figure 9 the deceleration slope shown in ⑥-1 of Figure 9 , the torque for vehicle stop is applied to the motor to increase the braking deceleration, and the torque for vehicle stop is limited to

[0148] the maximum regenerative braking torque (paddle regeneration TQ) shown in ⑥-2 of Figure 9 . In this case, when the torque for vehicle stop reaches the maximum regenerative braking torque (paddle regeneration TQ) represented by ⑥-2 of Figure 9 , braking cooperative control is performed by the AHB 250 or the EPB (electric parking brake system) as shown in ⑥-3 of

[0149] to generate hydraulic braking force, and thus the vehicle stops.

[0150] Changing the shift mode for deceleration control

[0151] As described above, the function of performing the switching operation of the paddle 210 and the function of controlling the shift mode of the transmission for controlling the regenerative braking amount and deceleration control for the front wheels can be performed together.

[0152] As described above, the deceleration increase control according to the holding operation of the (-) paddle and the shift control for deceleration increase according to the shift mode preset for the front wheels as shown in Figure 9 ⑦ are performed simultaneously, and the vehicle deceleration can be easily increased to the maximum target deceleration.

[0153] During the operation of the brake pedal

[0154] As described above, if the driver presses the brake pedal when increasing the deceleration by switching or holding the (-) paddle or when decreasing the deceleration by switching or holding the (+) paddle, braking cooperative control using both the regenerative braking force and the hydraulic braking force is performed.

[0155] That is to say, as described above, when the driver presses the brake pedal while the deceleration is increased or decreased by switching or holding the (-) paddle, or the deceleration is decreased by switching or holding the (+) paddle, the basic motor regenerative braking amount (coasting regeneration) represented by ①-1 of Figure 9 is the regenerative braking amount, and the hydraulic braking force of the AHB 250 of the braking system is added thereto, so the vehicle stops.

[0156] In the sport mode

[0157] As described above, when the current driving mode is determined to be the sport mode, the HCU 220 does not perceive the operation function of the paddle 210 as the function of adjusting the regenerative braking amount, but perceives the function of manually controlling the gear position of the transmission.

[0158] Therefore, the lower gear transmission that can be executed according to the manual switching operation of the (-) paddle 212 and the higher gear transmission that can be executed according to the manual switching operation of the (+) paddle 214 can be performed, and the control of changing the deceleration control mode by manually operating the gear change mode of the front-wheel transmission can be performed.

[0159] When shifting to the N gear during driving with regenerative braking

[0160] As described above, when the current driving mode is determined to be the eco mode in the HCU 220, the function of the paired paddle 210 including the (-) paddle 212 and the (+) paddle 214 is changed to the function of adjusting the regenerative braking amount, and the regenerative braking is controlled by operating the (-) paddle 212 and the (+) paddle 214.

[0161] When shifting the gear position to the N gear during driving with regenerative braking operation, the HCU 220 sends a signal to stop all regenerative braking to the MCU 230 while the TCU 240 sends an N gear signal to the HCU 220. Therefore, the regenerative braking of the motor stops.

[0162] In this case, when returning from the N (neutral) gear to the D (drive) gear, the HCU 220 sends a command signal to return to the regenerative braking amount to the MCU 230 before the N gear operation. Therefore, regenerative braking is performed before the N gear operation.

[0163] For example, when adjusted to be the Figure 9 basic motor regenerative braking amount (coasting regeneration) represented by ①-1, the regenerative braking return before the N gear operation is the same basic motor regenerative braking amount (coasting regeneration) as the basic motor regenerative braking amount when returning from the N gear to the D gear.

[0164] In addition, when adjusted to be Figure 9When at the first additional regenerative braking amount (coasting regeneration TQ 1) shown in ②-1, before the N-range operation, the regenerative braking returns to the same first additional regenerative braking amount (coasting regeneration TQ 1) as when returning from the N range to the D range.

[0165] In addition, when adjusted to Figure 9 the second additional regenerative braking amount (coasting regeneration TQ 2) shown in ②-2, before the N-range operation, the regenerative braking returns to the same second additional regenerative braking amount (coasting regeneration TQ 2) as when returning from the N range to the D range.

[0166] In addition, when adjusted to Figure 9 the third additional regenerative braking amount (coasting regeneration TQ 3) shown in ②-3, before the N-range operation, the regenerative braking returns to the same third additional regenerative braking amount (coasting regeneration TQ 3) as when returning from the N range to the D range.

[0167] In addition, when adjusted to the maximum regenerative braking torque (paddle regeneration TQ) indicated by Figure 9 ③-1, before the N-range operation, the regenerative braking returns to the same maximum regenerative braking torque (paddle regeneration TQ) as when returning from the N range to the D range.

[0168] During the regenerative braking operation, in the case of ABS or TCS operation

[0169] As described above, when ABS (antilock braking system) or TCS (traction control system), which is a type of emergency braking system, operates during driving under the regenerative braking control of operating the (-) paddle 212 and (+) paddle 214, in order to ensure braking safety, the HCU 220 sends a signal to stop all regenerative braking to the MCU 230. As a result, the regenerative braking of the motor stops.

[0170] In this case, when the operation of ABS or TCS stops, the HCU 220 sends a command signal to return the regenerative braking amount to the MCU 230 before the operation of ABS or TCS, so regenerative braking is performed before the operation of ABS or TCS.

[0171] For example, when adjusted to Figure 9 the basic motor regenerative braking amount (coasting regeneration) indicated by ①-1, before the operation of ABS or TCS, the regenerative braking returns to the same basic motor regenerative braking amount (coasting regeneration) as when the operation of ABS or TCS stops.

[0172] In addition, when adjusted to Figure 9When at the first additional regenerative braking amount (coasting regeneration TQ 1) shown in ②-1, before the operation of ABS or TCS, the regenerative braking returns to the same first additional regenerative braking amount (coasting regeneration TQ 1) as that at the stop of the operation of ABS or TCS.

[0173] In addition, when adjusted to Figure 9 the second additional regenerative braking amount (coasting regeneration TQ 2) shown in ②-2, before the operation of ABS or TCS, the regenerative braking returns to the same second additional regenerative braking amount (coasting regeneration TQ 2) as that at the stop of the operation of ABS or TCS.

[0174] Furthermore, when adjusted to Figure 9 the third additional regenerative braking amount (coasting regeneration TQ 3) shown in ②-3, before the operation of ABS or TCS, the regenerative braking returns to the same third additional regenerative braking amount (coasting regeneration TQ 3) as that at the stop of the operation of ABS or TCS.

[0175] In addition, when adjusted to the maximum regenerative braking torque (paddle regeneration TQ) indicated by Figure 9 ③-1, before the operation of ABS or TCS, the regenerative braking returns to the same maximum regenerative braking torque (paddle regeneration TQ) as that at the stop of the operation of ABS or TCS.

[0176] The power distribution between the front and rear wheels is controlled by the steering wheel operation

[0177] As described above, when it is determined that the steering of the steering wheel is operated above the reference angle during the regenerative braking control and deceleration control by operating the (-) paddle 212 and the (+) paddle 214, the torque ratio between the front-wheel motor and the rear-wheel motor can be controlled.

[0178] That is, in addition to the vehicle speed and deceleration, the torque and power ratios between the front-wheel motor and the rear-wheel motor can also be changed according to the steering angle of the steering wheel.

[0179] For example, when the steering angle sensor detects that the steering angle of the steering wheel is equal to or greater than the reference angle, the HCU 220 sends a command signal for changing the torque ratio and power ratio between the front-wheel motor and the rear-wheel motor to the MCU. Therefore, the torque and power ratios between the front-wheel motor and the rear-wheel motor can be variably controlled according to the steering angle.

[0180] As described above, in an AWD hybrid vehicle, the front wheel deceleration is controlled by manipulating the paddles by the driver to control the torque and shift mode of the front wheel motor, and at the same time, the rear wheel deceleration is controlled by manipulating the paddles by the driver to control the torque of the rear wheel motor, so that the optimal regenerative braking energy can be restored. Therefore, during the process of manipulating the (-) paddle and the (+) paddle, the fuel efficiency can be improved and the regenerative braking can be variably controlled according to the vehicle driving conditions, so that more intuitive regenerative braking can be performed.

Claims

1. A regenerative braking control system for an all-wheel drive hybrid vehicle, the all-wheel drive hybrid vehicle including a front-wheel hybrid electric vehicle powertrain and a rear-wheel electric vehicle powertrain, the regenerative braking control system including: A control instrument, mounted on the steering wheel for manual gear shifting and regenerative braking control through the driver's operation; And A controller configured to adjust the regenerative braking amount of each of a front-wheel motor of the front-wheel hybrid electric vehicle powertrain and a rear-wheel motor of the rear-wheel electric vehicle powertrain and control the gear shifting mode by receiving a (-) or (+) switching operation signal or a holding operation signal of the control instrument; Wherein, when the vehicle is in a coasting state and its driving mode is an eco-friendly mode, upon receiving the (-) switching operation signal or the holding operation signal of the control instrument, the controller is configured to variably set the torque ratio between the front-wheel motor and the rear-wheel motor, and then output the torque command signal and the gear shifting mode control signal to increase the adjustment of the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor; The controller is configured to: Determine whether the first operation signal for performing the (-) operation of the control instrument is an initial single-switching input signal or a single-holding input signal; Within a predetermined time after receiving the initial single-switching input signal, receive an additional single-switching input signal for continuously performing the (-) operation of the control instrument; Whenever the additional single-switching input signal is received, execute control to increase the regenerative braking torque of the front-wheel motor and the rear-wheel motor to a predetermined level; and Execute gear shifting control based on a preset gear shifting mode for the front wheels to increase the deceleration; After receiving the single-holding input signal as the first operation signal for performing the (-) operation of the control instrument in the controller, execute control to increase the regenerative braking torque of the front-wheel motor to the maximum regenerative braking torque, execute control to increase the regenerative braking torque of the rear-wheel motor to a predetermined level, and execute gear shifting control based on a preset gear shifting mode for the front wheels to increase the deceleration.

2. The regenerative braking control system according to claim 1, wherein The control instrument includes a pair of paddles, the pair of paddles including a (-) paddle and a (+) paddle capable of performing a switching operation or a holding operation.

3. The regenerative braking control system according to claim 1, wherein, The controller includes: A hybrid control unit configured to variably set the torque ratio between the front-wheel motor of the front-wheel hybrid electric vehicle powertrain and the rear-wheel motor of the rear-wheel electric vehicle powertrain after receiving the (-) or (+) switching operation signal or the holding operation signal of the control instrument, and then output a torque command signal and a gear shifting mode control signal to adjust the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor; A motor control unit configured to adjust the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor based on the torque command signal for adjusting the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor; and A transmission control unit configured to perform shift control of an automatic transmission based on the shift mode control signal.

4. The regenerative braking control system according to claim 3, wherein, To determine the coasting state of the vehicle, the off detection signals of an accelerator position sensor and a brake position sensor are sent to the hybrid control unit during the operation of the vehicle.

5. The regenerative braking control system according to claim 3 further comprises: A driving mode selection switch configured to select a vehicle driving mode as an eco mode or a sport mode, and a switching signal of the driving mode selection switch is sent to the hybrid control unit during the operation of the vehicle.

6. The regenerative braking control system according to claim 3, wherein, When the vehicle is in a coasting state and its driving mode is the eco mode, and when the hybrid control unit receives the (+) switching manipulation signal or the holding manipulation signal of the manipulation instrument, the hybrid control unit is configured to variably set the torque ratio between the front-wheel motor and the rear-wheel motor, and then output the torque command signal and the shift mode control signal to reduce the adjustment of the regenerative braking amount of each of the front-wheel motor and the rear-wheel motor.

7. The regenerative braking control system according to claim 3, wherein, When the vehicle is in a coasting state and its driving mode is the sport mode, the hybrid control unit is configured to send a lower gear transmission command signal of a gear lower than the current gear to the transmission control unit when receiving the (-) switching manipulation signal of the manipulation instrument, and the hybrid control unit is configured to send a higher gear transmission command signal of a gear higher than the current gear to the transmission control unit when receiving the (+) switching manipulation signal of the manipulation instrument.

8. The regenerative braking control system according to claim 3, further comprising: A power-assisted hydraulic brake configured to receive a cooperative control signal for distributing the total braking force from the hybrid control unit when the driver presses the brake pedal, and generate a hydraulic braking pressure of a hydraulic braking system in addition to the regenerative braking force of the motor.

9. A regenerative braking control method for an all-wheel drive hybrid vehicle, the all-wheel drive hybrid vehicle including a front-wheel hybrid electric vehicle powertrain and a rear-wheel electric vehicle powertrain, the regenerative braking control method comprising: Determining in a controller whether the vehicle is in a coasting state or the current driving mode; When it is determined in the controller that the vehicle is in the coasting state and its driving mode is the eco mode, changing the function of the manipulation instrument to a function of adjusting the regenerative braking amount; and When the controller receives the (-) or (+) switching manipulation signal or the holding manipulation signal of the manipulation instrument, adjusting the regenerative braking amount of each of the front-wheel motor of the front-wheel hybrid electric vehicle powertrain and the rear-wheel motor of the rear-wheel electric vehicle powertrain and controlling the shift mode; The regenerative braking control method further comprises: Determine whether the first manipulation signal for performing the (-) manipulation of the manipulation instrument is an initial one-time switching input signal or a one-time hold input signal; After determining that the first manipulation signal is the initial one-time switching input signal, the controller sets a target deceleration of the vehicle speed and sets a variable torque ratio between the front-wheel motor and the rear-wheel motor to a target torque ratio that satisfies the target deceleration; The controller receives an additional one-time switching input signal for continuously performing the (-) manipulation of the manipulation instrument within a predetermined time after receiving the initial one-time switching input signal; Whenever the additional one-time switching input signal is received, control is executed to increase the regenerative braking torque of the front-wheel motor and the rear-wheel motor to a predetermined level; Execute shift control based on a shift pattern preset for the front wheels to increase the deceleration; and After receiving the one-time hold input signal as the first manipulation signal for performing the (-) manipulation of the manipulation instrument in the controller, control is executed to increase the regenerative braking torque of the front-wheel motor to the maximum regenerative braking torque, control is executed to increase the regenerative braking torque of the rear-wheel motor to a predetermined level, and shift control is executed based on a shift pattern preset for the front wheels to increase the deceleration.

10. The regenerative braking control method according to claim 9, wherein, Adjusting the regenerative braking amount and controlling the shift pattern includes: the hybrid control unit of the controller variably sets a torque ratio between the front-wheel motor of the front-wheel hybrid electric vehicle powertrain and the rear-wheel motor of the rear-wheel electric vehicle powertrain, and then outputs a torque command signal and a shift pattern control signal for adjusting the regenerative braking amounts of the front-wheel motor and the rear-wheel motor.

11. The regenerative braking control method according to claim 9, wherein, When the hybrid control unit of the controller receives signals from a vehicle speed sensor, an accelerator position sensor, and a brake position sensor, when the vehicle speed is higher than 0 KPH, the accelerator position sensor is off, and the brake position sensor is off, it is determined that the vehicle is in the coasting state.

12. The regenerative braking control method according to claim 9, further comprising: Determine whether the second manipulation signal for performing the (+) manipulation of the manipulation instrument is an initial one-time switching input signal or a one-time hold input signal; And After determining that the second manipulation signal is the initial one-time switching input signal, the hybrid control unit of the controller sets a release of the target deceleration of the vehicle speed and sets the torque ratio between the front-wheel motor and the rear-wheel motor to a torque ratio for the target deceleration release.

13. The regenerative braking control method according to claim 12, further comprising: Within a predetermined time after receiving the initial one-time switching input signal, receive an additional one-time switching input signal for continuously performing the (+) manipulation of the manipulation instrument; Whenever the additional one-time switching input signal is received, execute control to reduce the regenerative braking torque of the front-wheel motor to a predetermined level; And Execute shift control based on a shift pattern preset for the front wheels to reduce the deceleration.

14. The regenerative braking control method according to claim 9 further includes: determining that a second manipulation signal for performing a (+) manipulation of the manipulation instrument is a one-time hold input signal; and setting, by the hybrid control unit of the controller, a target deceleration release of the vehicle speed, and setting a torque ratio between the front-wheel motor and the rear-wheel motor to a torque ratio for the target deceleration release.

15. The regenerative braking control method according to claim 14 further includes: in the hybrid control unit of the controller, receiving the one-time hold input signal as the second manipulation signal for a (+) manipulation of the manipulation instrument; performing control to reduce the regenerative braking torque of the front-wheel motor to a reference regenerative braking torque; and performing shift control based on a shift pattern preset for the front wheels to reduce the deceleration.

16. The regenerative braking control method according to claim 9 further includes: determining that the current driving mode is a sport mode; and changing, by the hybrid control unit of the controller, the function of the manipulation instrument to a shift gear adjustment function of a transmission, such that when a first manipulation signal for a (-) shift manipulation is received, control for reducing the shift gear is performed, and when a second manipulation signal for a (+) shift manipulation is received, control for increasing the shift gear is performed.

17. The regenerative braking control method according to claim 9 further includes: holding a (-) manipulation of the manipulation instrument for a predetermined time or longer; limiting the motor torque to a maximum regenerative braking torque; and performing braking cooperative control through an active hydraulic booster or an electric parking brake system to generate a hydraulic braking force.

18. The regenerative braking control method according to claim 9, wherein, When the anti-lock braking system or the traction control system is operating during driving under a regenerative braking operation, when shifting to the N gear during driving under the regenerative braking operation, the regenerative braking of the front-wheel motor and the rear-wheel motor stops, and when returning from the N gear to the D gear and when the operation of the anti-lock braking system or the traction control system is released, the regenerative braking of the front-wheel motor and the rear-wheel motor is performed with the previous regenerative braking amount.

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