US-12623639-B2 - Electronic brake system and control method therefor

US12623639B2US 12623639 B2US12623639 B2US 12623639B2US-12623639-B2

Abstract

An electronic brake system includes: a master cylinder connected to a brake pedal; a hydraulic pressure supply device including a motor that generates a rotational force and a hydraulic piston movably accommodated in a pressure chamber, and configured to generate a hydraulic pressure by a movement of the hydraulic piston; a hydraulic control unit configured to control a flow of the hydraulic pressure transferred to a wheel cylinder from the hydraulic pressure supply device; a hydraulic block in which the master cylinder, the hydraulic pressure supply device and the hydraulic control unit are integrated; and a controller configured to control the motor and the hydraulic control unit, wherein, during an anti-lock braking system (ABS) operation, the controller is configured to generate vibration in the motor by supplying the motor with an excitation current for exciting the motor to notify a driver of the ABS operation by vibration of the brake pedal.

Inventors

Kyoungjin JOO
Jinkuk PARK

Assignees

HL MANDO CORPORATION

Dates

Publication Date: 20260512
Application Date: 20210122
Priority Date: 20200123

Claims (16)

1 . An electronic brake system, comprising: a master cylinder connected to a brake pedal; a hydraulic pressure supply device comprising a motor that generates a rotational force and a hydraulic piston movably accommodated in a pressure chamber, and configured to generate a hydraulic pressure by a movement of the hydraulic piston; a hydraulic control unit configured to control a flow of the hydraulic pressure transferred to a wheel cylinder from the hydraulic pressure supply device; a hydraulic block in which the master cylinder, the hydraulic pressure supply device and the hydraulic control unit are integrated; and a controller configured to control the motor and the hydraulic control unit, wherein, the controller is configured to, during an anti-lock braking system (ABS) operation, add an excitation current for exciting the motor to a current for controlling a speed of the motor such that the motor is vibrated by the excitation current added to the current for controlling the speed of the motor, and transmit vibration, generated by the motor's being vibrated by the excitation current added to the current for controlling the speed of the motor, to the brake pedal through the hydraulic block in which the motor and the brake pedal are jointly mounted to notify a driver of the ABS operation.
2 . The electronic brake system of claim 1 , wherein the controller is configured to generate vibration simulating a kickback of the brake pedal in the motor in an ABS operation period.
3 . The electronic brake system of claim 2 , wherein the controller is configured to periodically repeat an ABS operation notification ON period for which the excitation current is supplied and an ABS operation notification OFF period for which the excitation current is not supplied, in the ABS operation period.
4 . The electronic brake system of claim 1 , wherein the controller is configured to supply the motor with an excitation current of a frequency which does not overlap an ABS operation frequency band.
5 . The electronic brake system of claim 1 , wherein the controller is configured to generate the vibration in the motor to generate vibration simulating a kickback of the brake pedal in an ABS operation period and generate an alarm sound due to shaking of a vehicle body.
6 . The electronic brake system of claim 5 , wherein the controller is configured to supply the motor with an excitation current having a plurality of frequencies different from each other.
7 . The electronic brake system of claim 6 , wherein the controller is configured to supply the motor with an excitation current in which a first frequency and a second frequency are continuously repeated, to generate an alarm sound where two sounds are repeated.
8 . The electronic brake system of claim 1 , wherein, during the ABS operation, the controller is configured to generate the excitation current by adding an excitation current command for generating the excitation current to a q-axis current command among the q-axis current command and a d-axis current command generated according to a target pressure.
9 . The electronic brake system of claim 1 , wherein the excitation current added to the current for controlling the speed of the motor is a dithering signal.
10 . A control method of an electronic brake system comprising a master cylinder connected to a brake pedal; a hydraulic pressure supply device comprising a motor that generates a rotational force and a hydraulic piston movably accommodated in a pressure chamber, and configured to generate a hydraulic pressure by a movement of the hydraulic piston; a hydraulic control unit configured to control a flow of the hydraulic pressure transferred to a wheel cylinder from the hydraulic pressure supply device; a hydraulic block in which the master cylinder, the hydraulic pressure supply device and the hydraulic control unit are integrated; and a controller configured to control the motor and the hydraulic control unit, the control method comprising: during an ABS operation, adding an excitation current for exciting the motor to a current for controlling a speed of the motor such that the motor is vibrated by the excitation current added to the current for controlling the speed of the motor to notify a driver of the ABS operation, and transmitting vibration, generated by the motor's being vibrated by the excitation current added to the current for controlling the speed of the motor, to the brake pedal through the hydraulic block in which the motor and the brake pedal are jointly mounted.
11 . The control method of claim 10 , wherein vibration simulating a kickback of the brake pedal is caused to be generated in the motor in an ABS operation period.
12 . The control method of claim 11 , wherein an ABS operation notification ON period for which the excitation current is supplied and an ABS operation notification OFF period for which the excitation current is not supplied are periodically repeated in the ABS operation period.
13 . The control method of claim 10 , wherein the vibration is caused to be generated in the motor to generate vibration simulating a kickback of the brake pedal in an ABS operation period and generate an alarm sound due to shaking of a vehicle body.
14 . The control method of claim 13 , wherein the motor is supplied with an excitation current having a plurality of frequencies different from each other.
15 . The control method of claim 14 , wherein the motor is supplied with an excitation current in which a first frequency and a second frequency are continuously repeated, to generate an alarm sound where two sounds are repeated.
16 . The control method of claim 10 , wherein the excitation current added to the current for controlling the speed of the motor is a dithering signal.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is the U.S. National Stage of International Patent Application No. PCT/KR2021/000905 filed on Jan. 22, 2021, which claims the priority to Korean Patent Application No. 10-2020-0009190 filed in the Korean Intellectual Property Office on Jan. 23, 2020, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD The disclosure relates to an electronic brake system that generates a braking force according to an electrical signal corresponding to a displacement of a brake pedal and a control method thereof. BACKGROUND ART As part of the preparation for emergency braking, autonomous driving and ongoing demand for eco-friendly technology and safety, the development of a brake-by-wire system that replaces mechanical connections among components of a master cylinder, a booster, an anti-lock braking system (ABS)/electronic stability control (ESC) with electrical and electronic connections is rapidly in progress. In particular, a demand for an integrated electronic brake system that integrates a master cylinder and an actuator into a single block to reduce engine load, reduce weight and allow more design flexibility is increasing. Unlike an existing brake system, when ABS is activated, because a direct connection between a master cylinder and a wheel brake is disconnected in the integrated electronic brake system, a driver's brake pedal operation is not directly linked to the wheel brake. Accordingly, a kickback phenomenon where a brake pedal vibration occurs during an ABS operation does not occur, and thus a driver may not recognize whether ABS is operating. Also, since an ABS noise is not loud, the driver may not be aware of whether ABS is operating, causing a difficulty in the driver's defensive driving. Therefore, in the integrated electronic brake system, a new method is required for allowing a driver to recognize whether ABS is operating during an ABS operation. DISCLOSURE Technical Problem An aspect of the disclosure provides an electronic brake system and a control method thereof that may notify a driver of whether ABS is operating when ABS is activated. Technical Solution According to an aspect of the disclosure, there is provided an electronic brake system including: a master cylinder connected to a brake pedal; a hydraulic pressure supply device including a motor that generates a rotational force and a hydraulic piston movably accommodated in a pressure chamber, and configured to generate a hydraulic pressure by a movement of the hydraulic piston; a hydraulic control unit configured to control a flow of the hydraulic pressure transferred to a wheel cylinder from the hydraulic pressure supply device; a hydraulic block in which the master cylinder, the hydraulic pressure supply device and the hydraulic control unit are integrated; and a controller configured to control the motor and the hydraulic control unit, wherein, during an anti-lock braking system (ABS) operation, the controller is configured to generate vibration in the motor by supplying the motor with an excitation current for exciting the motor to notify a driver of the ABS operation by vibration of the brake pedal. The controller is configured to generate vibration simulating a kickback of the brake pedal in the motor in an ABS operation period. The controller is configured to periodically repeat an ABS operation notification ON period for which the excitation current is supplied and an ABS operation notification OFF period for which the excitation current is not supplied, in the ABS operation period. The controller is configured to supply the motor with an excitation current of a frequency which does not overlap an ABS operation frequency band. The controller is configured to generate the vibration in the motor to generate vibration simulating a kickback of the brake pedal in an ABS operation period and generate an alarm sound due to shaking of a vehicle body. The controller is configured to supply the motor with an excitation current having a plurality of frequencies different from each other. The controller is configured to supply the motor with an excitation current in which a first frequency and a second frequency are continuously repeated, to generate an alarm sound where two sounds are repeated. During the ABS operation, the controller is configured to generate the excitation current by adding an excitation current command for generating the excitation current to a q-axis current command among the q-axis current command and a d-axis current command generated according to a target pressure. According to another aspect of the disclosure, there is provided a control method of an electronic brake system including a master cylinder connected to a brake pedal; a hydraulic pressure supply device including a motor that generates a rotational force and a hydraulic piston movably accommodated in a pressure chamber, and configured to generate a hydraulic pressure by a movem