阅读说明：本技术 车辆控制系统、车辆控制系统的控制方法及制动装置 (vehicle control system, control method of vehicle control system, and brake device ) 是由 朴麟惠 于 2019-05-30 设计创作，主要内容包括：根据本发明的一方面涉及一种车辆控制系统,该系统能够改变并调节滑行时由马达产生的再生制动转矩,从而提高行驶稳定性,并向驾驶员提供稳定的驾驶乐趣。根据本发明的一个实施例的车辆控制系统包括：马达,向车轮提供驱动力；车轮传感器,感测所述车轮的旋转速度；以及控制部,滑行过程中,控制所述马达产生第一再生制动转矩,当基于所述车轮传感器的输出感测到所述车轮的车轮打滑时,控制所述马达产生小于所述第一再生制动转矩的第二再生制动转矩。(According to an aspect of the present invention, there is provided a vehicle control system capable of varying and adjusting a regenerative braking torque generated by a motor during coasting, thereby improving driving stability and providing a driver with stable driving pleasure. A vehicle control system according to an embodiment of the present invention includes: a motor that provides driving force to the wheel; a wheel sensor that senses a rotational speed of the wheel; and a control section that controls the motor to generate a first regenerative braking torque during coasting, and controls the motor to generate a second regenerative braking torque smaller than the first regenerative braking torque when it is sensed that a wheel of the wheel slips based on an output of the wheel sensor.)

1. A vehicle control system comprising:

A motor that provides driving force to the wheel;

A wheel sensor that senses a rotational speed of the wheel; and

And a control unit that controls the motor to generate a first regenerative braking torque during coasting and controls the motor to generate a second regenerative braking torque smaller than the first regenerative braking torque when a wheel slip of the wheel is sensed based on an output of the wheel sensor.

2. The vehicle control system according to claim 1, further comprising:

An accelerator pedal that receives an acceleration instruction from a driver; and

A brake pedal receiving a braking command from the driver,

The control unit controls the motor to generate a first regenerative braking torque when the acceleration command and the braking command are not received.

3. The vehicle control system according to claim 1, further comprising:

An input part receiving a regenerative braking level from a driver,

The control unit determines the magnitude of the first regenerative braking torque based on the regenerative braking level.

4. the vehicle control system according to claim 3,

The control unit determines the magnitude of the second regenerative braking torque based on the braking efficiency.

5. The vehicle control system according to claim 1,

the control portion determines the wheel slip according to a result of comparison of a wheel slip value calculated based on the rotation speed of the wheel with a predetermined reference value.

6. The vehicle control system according to claim 5,

The reference value is determined based on at least one of the vehicle speed, the regenerative braking level, and a road surface state.

7. A control method of a vehicle control system, comprising:

Rotating the wheel by a motor;

generating a first regenerative braking torque by the motor during coasting;

Sensing a rotational speed of the wheel during the coasting;

Generating, by the motor, a second regenerative braking torque smaller than the first regenerative braking torque at the time of coasting when a wheel slip is sensed based on an output of the wheel sensor.

8. The control method of a vehicle control system according to claim 7,

Generating the first regenerative braking torque comprises:

The first regenerative braking torque is generated when no acceleration command and no braking command are received.

9. The control method of a vehicle control system according to claim 8,

The control method further includes receiving a level of regenerative braking from a driver,

generating the first regenerative braking torque comprises:

The magnitude of the first regenerative braking torque is determined based on the regenerative braking level.

10. The control method of a vehicle control system according to claim 7,

generating the second regenerative braking torque comprises:

And judging the magnitude of the second regenerative braking torque based on the braking efficiency.

11. The control method of a vehicle control system according to claim 7,

Sensing wheel slip based on the output of the wheel sensor includes:

the wheel slip is determined based on a result of comparison of a wheel slip value calculated based on the rotation speed of the wheel with a predetermined reference value.

12. The control method of a vehicle control system according to claim 11,

The reference value is determined based on at least one of the vehicle speed, the regenerative braking level, and a road surface state.

13. A brake device that brakes a vehicle including a motor for driving a wheel and a drive device for controlling the motor, the brake device comprising:

A wheel sensor that senses a rotational speed of the wheel; and

And a control unit that receives information on a first regenerative braking torque from the drive unit during coasting, determines a wheel slip of the wheel based on an output of the wheel sensor, and transmits information on a second regenerative braking torque to the drive unit in response to a determination result when the wheel slip is determined, so as to control the motor to generate a second regenerative braking torque smaller than the first regenerative braking torque.

14. The braking device according to claim 13,

The control unit determines the magnitude of the second regenerative braking torque based on the braking efficiency.

15. The braking device according to claim 13,

The control portion determines the wheel slip according to a result of comparison of a wheel slip value calculated based on the rotation speed of the wheel with a predetermined reference value.

16. the braking device according to claim 15,

The reference value is determined based on at least one of the vehicle speed, the regenerative braking level, and a road surface state.

Technical Field

The present invention relates to a vehicle control system that controls regenerative braking torque generated by a motor during coasting, and a control method thereof.

Background

In the modern society, vehicles are the most commonly used vehicles, and the number of people using vehicles is gradually increasing. With the development of vehicle technology, many changes have occurred in life, such as greater convenience in moving over long distances than in the past, and greater comfort in life.

Here, the vehicle includes an internal combustion engine vehicle (general engine vehicle) that burns petroleum fuel such as gasoline, light oil to generate mechanical power and runs using the mechanical power, and an eco-friendly vehicle that runs using electric power as power to reduce fuel consumption and emission of harmful gases.

Here, the environmentally friendly vehicle includes an electric vehicle including a battery and a motor as a chargeable power supply portion, rotating the motor using electric power stored in the battery, and driving wheels using rotation of the motor, a hybrid vehicle including an engine, a battery, and a motor, and traveling by controlling mechanical power of the engine and electromotive power of the motor, and a hydrogen fuel cell vehicle.

the Hybrid Vehicle may be driven in an Electric Vehicle (EV) mode using only power of a motor, or may be driven in a Hybrid Electric Vehicle (HEV) mode using power of an engine and power of a motor, and a Regenerative Braking mode (Regenerative Braking) in which Braking and inertial energy are recovered by a power generation operation of a motor to charge a battery is performed at the time of Braking or coasting (coasting).

In addition, a vehicle control System (Brake System) may be included in the vehicle to reduce the speed of the vehicle or stop the vehicle as needed in a driving state. A vehicle control system is also provided in an eco-friendly vehicle employing a motor, and various technologies for controlling the rotational torque of the wheels generated by the vehicle control system are being developed.

Disclosure of Invention

Technical problem to be solved

An aspect of the present invention relates to a vehicle control system and a control method thereof, which can vary and adjust a Regenerative Braking Torque (Coasting Regenerative Braking Torque) generated by a motor during Coasting, thereby improving Driving stability and providing a driver with stable Driving pleasure (Fun Driving).

(II) technical scheme

A vehicle control system according to an embodiment of the present invention includes: a motor that provides driving force to the wheel; a wheel sensor that senses a rotational speed of the wheel; and a control section that controls the motor to generate a first regenerative braking torque during coasting, and controls the motor to generate a second regenerative braking torque smaller than the first regenerative braking torque when it is sensed that a wheel of the wheel slips based on an output of the wheel sensor.

The vehicle control system may further include: an accelerator pedal that receives an acceleration instruction from a driver; and a brake pedal configured to receive a braking command from the driver, wherein the control unit is configured to control the motor to generate a first regenerative braking torque when the acceleration command and the braking command are not received.

The vehicle control system may further include an input portion that receives a regenerative braking level from a driver, and the control portion may determine the magnitude of the first regenerative braking torque based on the regenerative braking level.

The control portion may determine the magnitude of the second regenerative braking torque based on the braking efficiency.

The control portion may determine the wheel slip according to a result of comparison of a wheel slip value calculated based on the rotation speed of the wheel with a predetermined reference value.

The reference value may be determined based on at least one of the vehicle speed, the regenerative braking level, and a road surface state.

A control method of a vehicle control system according to an embodiment of the invention includes: rotating the wheel by a motor; generating a first regenerative braking torque by the motor during coasting; sensing a rotational speed of the wheel during the coasting; generating, by the motor, a second regenerative braking torque smaller than the first regenerative braking torque at the time of coasting when a wheel slip is sensed based on an output of the wheel sensor.

generating the first regenerative braking torque may include: the first regenerative braking torque is generated when no acceleration command and no braking command are received.

The control method may further include receiving a regenerative braking level from a driver, and generating the first regenerative braking torque may include: the magnitude of the first regenerative braking torque is determined based on the regenerative braking level.

Generating the second regenerative braking torque may include: and judging the magnitude of the second regenerative braking torque based on the braking efficiency.

Sensing wheel slip based on the output of the wheel sensor may include: the wheel slip is determined based on a result of comparison of a wheel slip value calculated based on the rotation speed of the wheel with a predetermined reference value.

The reference value may be determined based on at least one of the vehicle speed, the regenerative braking level, and a road surface state.

The braking device for braking a vehicle including a motor for driving a wheel and a driving device for controlling the motor according to the present invention may include: a wheel sensor that senses a rotational speed of the wheel; and a control portion that receives information related to a first regenerative braking torque from the drive device during coasting, determines a wheel slip of the wheel based on an output of the wheel sensor, and transmits information related to a second regenerative braking torque to the drive device in response to a determination result to control the motor to generate a second regenerative braking torque smaller than the first regenerative braking torque when the wheel slip is determined.

(III) advantageous effects

a vehicle control system and a control method thereof according to an aspect of the present invention can change and adjust a Coasting Regenerative braking torque (Fun Driving) generated by a motor when a wheel slip occurs during Driving, thereby improving Driving stability and providing a driver with stable Driving pleasure.

Drawings

Fig. 1 shows a part of a vehicle provided with a vehicle control system of one embodiment of the invention.

fig. 2 is a control block diagram of a vehicle control system of one embodiment of the invention.

fig. 3 is a diagram for explaining the regenerative braking level during coasting.

fig. 4 is a graph for explaining a control method of the vehicle control system of the embodiment.

FIG. 5 is a flowchart of a control method of a vehicle control system of an embodiment.

Description of the reference numerals

1: the vehicle control system 20: input unit

50: the control unit 60: battery with a battery cell

70: motor 80: speed variator

90: differential devices 91, 92: wheel of vehicle

Detailed Description

Like reference numerals refer to like elements throughout the specification. All elements of the embodiments are not described in the specification, and general contents or overlapping contents between the embodiments in the technical field to which the present invention belongs are omitted. The term "section, module, component, block" used in the specification may be implemented by software or hardware, or a plurality of "sections, modules, components, blocks" may be implemented by one component according to the embodiment, or one "section, module, component, block" may further include a plurality of components.

throughout the specification, when it is described that one part is "connected" to another part, it includes not only a case of direct connection but also a case of indirect connection, and indirect connection includes connection through a wireless communication network.

Also, when a portion is described as "including" a component, unless otherwise specified, it means that other components may be included without excluding other components.

The terms first, second, etc. are used to distinguish one element from another, and are not limited by the foregoing terms.

The singular forms include the plural unless the specification expressly states otherwise.

In each step (step), reference numerals are used for convenience of description, and the reference numerals do not describe the order of the steps, unless a specific order of the steps is explicitly described in the specification, and no group may be implemented in a manner different from the above order.

The operation principle and the embodiment of the present invention will be explained with reference to the drawings.

Fig. 1 shows a part of a vehicle provided with a vehicle control system of one embodiment of the invention. Fig. 2 is a control block diagram of a vehicle control system of one embodiment of the invention. Fig. 3 is a diagram for explaining the regenerative braking level during coasting. Fig. 4 is a graph for explaining a control method of the vehicle control system of the embodiment.

referring to fig. 1, 2, 3 and 4, the seat perimeter on which the driver sits may include: a steering wheel 12; an instrument panel 11(Cluster) which is provided from the steering wheel 12 toward the front of the eco-vehicle and indicates operation information of the eco-vehicle; and a Dashboard (Dashboard) connected to the Dashboard 11 and provided with various devices for operating the eco-vehicle.

For example, various devices provided in the dashboard may include a vent and various input and output devices connected to an Audio-Video Navigation (AVN) device or an air conditioner in a central monitoring dashboard (Center family) of a central region of the dashboard, and the like.

The instrument panel 11 displays the current state of the vehicle and operation information, and various display devices may be provided for this purpose.

the steering wheel 12 can adjust the direction of the wheels 91, 92, and the driver can adjust the driving stability by the steering wheel 12 when wheel slip occurs.

Shift gates 21, 22(Paddle Shifter) may be provided on the steering wheel 12 toward the dashboard 11.

The shift paddles 21, 22 may receive input commands from the driver relating to the regenerative braking level during coasting, which can control the magnitude of the regenerative braking torque during coasting.

In general, the braking torque at the time of coasting refers to the braking torque supplied to the wheels 91, 92 through the engine and the transmission of the vehicle in a state where the accelerator pedal 22 and the brake pedal 23 are not depressed. In a vehicle provided with an internal combustion engine, a braking torque at the time of coasting is adjusted in accordance with a converter control characteristic of an automatic transmission.

In an eco-vehicle not equipped with an engine and having the motor 70 as a power source, the regenerative braking torque at the time of coasting is 0. However, the eco-friendly vehicle can give the driver a driving feeling similar to that of a vehicle provided with an internal combustion engine, and generate regenerative braking torque at the time of coasting in order to take fuel economy into consideration.

The wheels 91, 92 may move the vehicle by rotating. The wheels 91, 92 in fig. 2 are shown only as a first wheel 91 and a second wheel 92 provided on the left and right sides of the eco-vehicle. However, four or more wheels may be provided depending on the type of vehicle.

in order to generate regenerative braking torque at the time of coasting, the vehicle control system 1 includes a drive device 10 and a brake device 100.

The driving device 10 may include: an input unit 20 that receives an input command related to regenerative braking during coasting from a driver; a motor 70 that receives electric power from the battery 60 and supplies driving force to the wheels 91, 92; a transmission 80 that transmits the rotational motion of the motor 70 to the wheels 91, 92; and a drive control unit 50 for controlling the above configuration.

Specifically, the input portion 20 receives various input commands from the driver regarding regenerative braking during coasting.

The input unit 20 may receive an input command related to the coasting regenerative braking level, and may transmit the coasting regenerative braking level to the drive control unit 50 based on an electric command transmitted from the shift dials 21 and 22, for example. The specific explanation of the regenerative braking level during coasting will be described later in detail.

The battery 60 generates electric power of high-voltage current and supplies the generated electric power to the motor 70. Furthermore, the battery 60 supplies electric power to the vehicle control system 1 and various electronic devices included in the eco-friendly vehicle provided with the vehicle control system 1.

The battery 60 may also receive electric power generated by a motor 70, which will be described later, or a Starter Generator (HSG) provided in the eco-vehicle to be charged.

The motor 70 receives electric power from the battery 60 as a power source that supplies driving force to the wheels 91, 92 included in the vehicle control system 1.

The rotation speed of the motor 70 is adjusted based on the displacement of the accelerator pedal 24. For example, when an accelerator pedal sensor (not shown) senses displacement of the accelerator pedal 24, the drive control section 50 determines a rotation speed (RPM) of the motor 70 corresponding to the magnitude of the displacement of the accelerator pedal 24, and controls the motor 70.

The motor 70 may operate as a generator according to a regenerative braking mode and may also charge the battery 60.

The transmission 80 transmits the rotational motion of the motor 70 to the wheels 91, 92.

If the Transmission 80 is provided between the motor 70 and an engine in the eco-friendly vehicle, the Transmission 80 may be a Dual Clutch Transmission (DCT) using two Clutch operation gears.

in the vehicle control system 1 of the invention, the transmission 80 may further include a Final Reduction & Differential gear 90 (FD) that changes the rotational speed (RPM) of the motor based on the displacement of the accelerator pedal 24.

Specifically, wheels 91, 92 are driven by the eco-vehicle, and differential device 90 transmits running torque generated by motor 70 to wheels 91, 92.

The drive control unit 50 controls the motor 70 to generate the first regenerative braking torque based on the coasting regenerative braking level transmitted from the input unit 20. That is, in the coasting state where there is no acceleration command or braking command from the driver, the drive control unit 50 brakes the vehicle based on the first regenerative braking torque.

as described above, the drive control portion 50 may determine the first regenerative braking torque according to the regenerative braking level at the time of coasting selected by the driver, and control the motor 70 to generate the first regenerative braking torque. Meanwhile, the drive control part 50 may transmit the first regenerative braking torque to the braking device 100. In addition, the drive control portion 50 receives a second regenerative braking torque from the brake device 100 in response to the first regenerative braking torque, and controls the motor 70 to generate the second regenerative braking torque received from the brake device 100.

The drive control section 50 may be a communication module (not shown) for communicating with other devices such as the brake device 100, a memory (not shown) storing data of a program related to an algorithm or a reproduction algorithm for controlling the drive device 10, and a processor (not shown) performing the above-described operations using the data stored in the memory. At this time, the communication module, the memory, and the processor may be implemented in separate chips, respectively. Alternatively, the communication module, the memory, and the processor may be implemented in a single chip.

In the graph of fig. 3, the X-axis represents time, and the Y-axis represents the magnitude of the generated regenerative braking torque during coasting, in Nm.

Referring to fig. 3, the driving apparatus 10 applied to the eco-friendly vehicle of the present invention generates the regenerative braking torque at the time of coasting of different magnitude according to different regenerative braking levels at the time of coasting. In addition, the drive device 10 controls the motor 70 so that the regenerative braking torque reaches a predetermined magnitude over time.

Here, the magnitude of the regenerative braking torque at the time of coasting with time is generated based on the regenerative braking level at the time of coasting, which is received by the driver. The driver can determine the regenerative braking level during coasting by means of the shift paddles 21, 22, in the seat in which the driver is seated, the regenerative braking level during coasting can be increased according to the right shift paddle 22 and the regenerative braking level during coasting can be decreased based on the input command transmitted by the left shift paddle 21.

The drive device 10 controls the motor 70 to generate the regenerative braking torque of the first regenerative braking torque magnitude based on the coasting regenerative braking level received from the driver.

The input command regarding the regenerative braking level during coasting may be transmitted not only via the shift dials 21 and 22 but also via various buttons and input methods.

The braking device 100 includes: a pedal sensor 110 sensing a braking intention of a driver; calipers 141, 142 that stop the rotation of the wheels 91, 92 by friction; wheel sensors 151, 152 that sense the rotational speed of the wheels 91, 92; an actuator 130 for hydraulically controlling the calipers 141 and 142 to stop the wheels 91 and 92; the brake control unit 120 controls the actuator 130 based on the output of the pedal sensor 110 and the outputs of the wheel sensors 151 and 152.

The pedal sensor 110 is provided in the brake pedal 23, and senses a position of the brake pedal 23 or a displacement of the brake pedal 23. When the driver depresses the brake pedal 23 to stop the vehicle, the pedal sensor 110 senses a position or displacement of the brake pedal 23, and transmits an electric signal corresponding to the sensed position or displacement to the brake control portion 120.

The calipers 141, 142 may stop the wheels 91, 92 by friction. For example, the brake calipers 141, 142 may clamp a disc that rotates together with the wheels 91, 92 by hydraulic pressure supplied by the actuator 130, thereby stopping rotation of the wheels 91, 92.

The calipers 141, 142 include a first caliper 141 for stopping the first wheel 91 and a second caliper 142 for stopping the second wheel 92.

The wheel sensors 151, 152 measure the rotation speeds of the wheels 91, 92, and transmit electric signals corresponding to the measured rotation speeds of the wheels 91, 92 to the brake control section 120.

The wheel sensors 151, 152 include a first wheel sensor 151 that senses the rotational speed of the first wheel 91 and a second wheel sensor 152 that senses the rotational speed of the second wheel 92.

The actuator 130 may generate a hydraulic pressure for controlling the operation of the brake calipers 141, 142 according to a brake control signal of the brake control portion 120. That is, the actuator 130 generates hydraulic pressure for the brake calipers 141, 142 to stop the wheels 91, 92, and supplies the generated hydraulic pressure to the brake calipers 141, 142.

the actuator 130 generates hydraulic pressure supplied to the first caliper 141 and hydraulic pressure supplied to the second caliper 142 independently. That is, the actuator 130 may provide different hydraulic pressures to the first and second brake calipers 141 and 142 to provide different braking forces to the first and second wheels 91 and 92.

The actuator 130 includes a pump, a valve, and the like operated according to a brake control signal of the brake control section 120. For example, the actuator 130 may include an inlet Valve (inlet Valve) that allows or prevents supply of hydraulic pressure to the brake calipers 141, 142 and an outlet Valve (outlet Valve) that allows or prevents reduction of hydraulic pressure to the brake calipers 141, 142.

The brake control section 120 controls the actuator 130 in response to the output signal of the pedal sensor 110 and the output signals of the wheel sensors 151, 152.

for example, the brake control portion 120 may determine the movement (displacement) of the brake pedal 23 based on the pedal sensor 110, and control the actuator 130 to supply the hydraulic pressure based on the movement (displacement) of the brake pedal 23 to the brake calipers 141, 142.

the brake control portion 120 may determine a wheel slip based on a difference between the output of the first wheel sensor 151 and the output of the second wheel sensor 152, and control the actuator 130 to stop braking of the wheels 91, 92 in response to the determination of the wheel slip. That is, in response to the determination of the wheel slip, the brake control portion 120 may control the actuator 130 to decrease the hydraulic pressure of the brake calipers 141, 142.

Also, the brake control portion 120 may receive the current regenerative braking torque from the drive control portion 50. In response to the reception of the current regenerative braking torque, the brake control portion 120 determines a wheel slip based on the difference between the output of the first wheel sensor 151 and the output of the second wheel sensor 152.

Alternatively, the brake control unit 120 determines the wheel slip based on the difference between the vehicle speed and the output of the wheel sensors 151 and 152. For example, the brake control portion 120 calculates an average rotation speed (vehicle speed) based on the collected rotation speeds of the plurality of wheels, and determines wheel slip based on the collected rotation speed and the vehicle speed.

When the wheel slip exceeds the target control region, the brake control portion 120 determines the second regenerative braking torque for reducing the braking force of the current vehicle. The second regenerative braking torque may be calculated based on the degree to which the wheel slip exceeds the target control region (e.g., the difference between the wheel slip and the maximum value of the target control region), and may be smaller than the first regenerative braking torque generated by the drive control portion 50.

Fig. 4 (a) is a graph for explaining wheel slip, fig. 4 (b) is a graph of a target control region relating to regenerative braking torque during coasting, and fig. 4 (c) is a graph of a result of a control method.

Referring to fig. 4 (a), the x-axis represents time and the y-axis represents velocity.

For example, while coasting, the drive device 10 may control the motor based on the first regenerative braking torque.

Since the first regenerative braking torque is generated in the decelerating direction, the vehicle speed 30 of the eco-vehicle decreases with time.

also, when the vehicle speed is reduced by the first regenerative braking torque, the eco-vehicle can travel on a road surface with small friction, and wheel slip can occur. When the wheel slip occurs, the rotation speed 31 of the wheel may be different from the vehicle speed 30 based on the rotation force transmitted from the motor 70. That is, the wheels 91, 92 may spin.

Referring to fig. 4 (b), the X-axis represents the degree of wheel slip and the Y-axis represents braking efficiency. As shown in fig. 4 (b), when the magnitude of the wheel slip is within the target control region 32 during regenerative braking, the braking efficiency is high. Therefore, upon departing from the target control region 32, slip can be reduced by reducing braking torque, and braking efficiency can be increased by reducing wheel slip.

Therefore, when the wheel slip is sensed, the brake control portion 120 controls the driving device 10 to cause the motor 70 to generate the second regenerative braking torque smaller than the first regenerative braking torque.

The brake control portion 120 monitors the degree of wheel slip. And, a second regenerative braking torque is generated based on the magnitude of the sensed wheel slip. Further, the brake control portion 120 transmits the second regenerative braking torque to the drive control portion 50 to control the motor 70 according to the second regenerative braking torque.

Referring to fig. 4 (c), the X-axis represents time and the Y-axis represents the magnitude of the braking torque. As described above, when wheel slip is sensed during operation of the motor 70 with the first regenerative braking torque, the vehicle control system 1 controls the motor 70 to generate the second regenerative braking torque smaller than the first regenerative braking torque of the motor 70.

Specifically, the automatic control portion 120 determines a second regenerative braking torque that is smaller than the first regenerative braking torque, and transmits the final regenerative braking torque to the drive control portion 50.

The second regenerative braking torque 35 increases or decreases by a predetermined amount based on the braking efficiency in addition to the first regenerative braking torque 33.

That is, the second regenerative braking torque 35 is based on the second braking efficiency in the target control region 32 determined according to the magnitude of the sensed wheel slip in (b) of fig. 4, and determines the magnitude of the second regenerative braking torque at the time of coasting according to the regenerative braking level at the time of coasting. Also, the second regenerative braking torque 35 may vary with time, for example, the second regenerative braking torque 35 may be generated at a similar inclination to the first regenerative braking torque 33 to be controlled according to the regenerative braking level.

The brake control part 120 may be a communication module (not shown) for communicating with other devices such as the driving device 10, a memory (not shown) storing data on a program for controlling an algorithm or a reproducing algorithm of the driving device 10, and a processor (not shown) performing the above-described operations using the data stored in the memory. At this time, the communication module, the memory, and the processor may be implemented in separate chips, respectively. Alternatively, the communication module, the memory, and the processor may be implemented in a single chip.

The brake control unit 120 may be provided separately from the drive control unit 50 or may be provided integrally with the drive control unit 50.

FIG. 5 is a flowchart of a control method of a vehicle control system of an embodiment.

Referring to fig. 5, the vehicle control system 1 receives an input command related to the regenerative braking level at the time of coasting (1000).

The input command related to the regenerative braking level when coasting may be input during the running of the eco-friendly vehicle, or may be received and stored in advance. For example, the regenerative braking level during coasting can be received by the shift paddles 20, 21 provided on the steering wheel 12.

The vehicle control system 1 determines whether the eco-vehicle is coasting during running (1100).

For example, the vehicle control system 1 may determine that the vehicle is coasting when the driver does not change the D range and does not depress the brake pedal 23 and the accelerator pedal 24 during running of the vehicle.

When it is determined not to coast (no in 1100), the vehicle control system 1 continues to determine whether to coast.

When it is determined to coast (yes at 1100), the vehicle control system 1 brakes the vehicle with a regenerative braking torque based on the regenerative braking level selected by the driver.

Specifically, the drive control portion 50 determines a first regenerative braking torque based on the regenerative braking level selected by the driver, and controls the motor 70 according to the determined first regenerative braking torque. Then, the drive control unit 50 transmits the first regenerative braking torque to the brake control unit 120.

The vehicle control system 1 continues to sense wheel slip (1200).

First, the vehicle control system 1 determines whether or not a wheel slip occurs by the following [ equation 1 ].

[ mathematical formula 1]

Where slip denotes the degree of occurrence of wheel slip, v denotes the vehicle speed, and rw denotes the rotational speed of the wheel at which wheel slip occurs.

Also, the vehicle speed is calculated based on the average rotational speed of the plurality of wheels 91, 92 provided in the eco-vehicle, and the criterion for determining the wheel slip is determined based on the rotational speed of each wheel provided in the vehicle.

That is, the brake control portion 120 calculates a vehicle speed based on the average rotation speed of the plurality of wheels 91, 92, and compares the degree (result value) of occurrence of a wheel slip calculated based on the calculated vehicle speed and the sensed rotation speed of the wheels with a predetermined reference value, thereby finally determining whether the wheel slip occurs.

The predetermined reference value may be set to various values according to the vehicle speed, the regenerative braking level, and the road surface state. For example, when the road surface state currently being traveled is an ice surface or an underground parking lot having moisture, the reference value becomes low.

When the wheel slip exceeds the reference value (yes of 1200), the vehicle control system 1 determines that the wheel slip occurs, adjusts the first regenerative braking torque based on the regenerative braking level, and determines the second regenerative braking torque (1300).

As described above, the adjusted regenerative braking torque may be adjusted based on the braking efficiency and the level of regenerative braking input by the driver.

Next, the vehicle control system 1 controls the motor 70(1400) based on the adjusted regenerative braking torque, i.e., the second regenerative braking torque.

The vehicle control system 1 disclosed herein can improve the Driving stability and provide the driver with a stable Driving pleasure (Fun Driving).

In addition, the embodiments disclosed in the present invention may be implemented in the form of a recording medium storing instructions executable by a computer. The instructions may be stored in the form of program code that, when executed by a processor, may generate program modules to perform the operations of the embodiments disclosed herein. The recording medium may be a computer-readable recording medium.

The computer-readable recording medium includes various recording media storing instructions that can be decoded by a computer. Such as Read Only Memory (ROM), Random Access Memory (RAM), magnetic tape, magnetic disk, flash Memory, optical data storage devices, and the like.

The embodiments of the present invention have been described above with reference to the drawings. Those skilled in the art to which the present invention pertains will appreciate that the present invention can be implemented in a form different from the above-described embodiments without changing the technical idea or essential features of the invention. The embodiments of the invention are exemplary and should not be construed as limiting.