ELECTRONIC PARKING BRAKE SYSTEM AND CONTROL METHOD THEREOF
An electronic parking brake system including: an electronic parking brake (EPB) including a piston that moves by a hydraulic pressure to press brake pads onto a brake disc, a cylinder in which the piston is provided movably forward and backward, and an EPB actuator that moves the piston by a motor to press the brake pads onto the brake disc; a pressure sensor configured to detect a hydraulic pressure of the cylinder; an electronic stability control (ESC) actuator configured to generate and supply a hydraulic pressure to the cylinder; and a controller configured to control the EPB actuator and the ESC actuator, wherein the controller is configured to detect an actual hydraulic pressure of the cylinder through the pressure sensor in an EPB disengagement, and when the detected actual hydraulic pressure is higher than a required hydraulic pressure, control the EPB actuator to start an EPB disengagement control.
1 . An electronic parking brake system, comprising:
an electronic parking brake (EPB) comprising a piston that moves by a hydraulic pressure to press brake pads onto a brake disc, a cylinder in which the piston is provided movably forward and backward, and an EPB actuator that moves the piston by a motor to press the brake pads onto the brake disc;
a pressure sensor configured to detect a hydraulic pressure of the cylinder;
an electronic stability control (ESC) actuator configured to generate and supply a hydraulic pressure to the cylinder; and
a controller configured to control the EPB actuator and the ESC actuator,
wherein the controller is configured to detect an actual hydraulic pressure of the cylinder through the pressure sensor in an EPB disengagement, and when the detected actual hydraulic pressure is higher than a required hydraulic pressure, control the EPB actuator to start an EPB disengagement control.
2 . The electronic parking brake system of claim 1 , wherein, when the detected actual hydraulic pressure is lower than the required hydraulic pressure, the controller is configured to supply the hydraulic pressure through the ESC actuator, until the detected actual hydraulic pressure reaches the required hydraulic pressure.
3 . The electronic parking brake system of claim 1 , wherein the controller is configured to identify the required hydraulic pressure according to a hydraulic pressure of the cylinder at a time of EPB engagement.
4 . The electronic parking brake system of claim 2 , further comprising:
a memory in which a hydraulic pressure of the cylinder at the time of EPB engagement is stored.
5 . The electronic parking brake system of claim 4 , wherein, in an EPB engagement, the controller is configured to detect the hydraulic pressure of the cylinder at the time of EPB engagement through the pressure sensor, and store the detected hydraulic pressure of the cylinder in the memory.
6 . The electronic parking brake system of claim 5 , wherein, in the EPB engagement, the controller is configured to store the detected hydraulic pressure of the cylinder in the memory, when the detected hydraulic pressure of the cylinder is higher than a preset hydraulic pressure.
7 . The electronic parking brake system of claim 5 , wherein, in the EPB engagement, when the detected hydraulic pressure of the cylinder is lower than a preset hydraulic pressure, the controller is configured to supply the hydraulic pressure through the ESC actuator, until the detected hydraulic pressure of the cylinder reaches the preset hydraulic pressure.
8 . A control method of an electronic parking brake system comprising an EPB having a piston that moves by a hydraulic pressure to press brake pads onto a brake disc, a cylinder in which the piston is provided movably forward and backward, and an EPB actuator that moves the piston by a motor to press the brake pads onto the brake disc, the control method comprising:
detecting an actual hydraulic pressure of the cylinder in an EPB disengagement; and
when the detected actual hydraulic pressure is higher than a required hydraulic pressure, controlling the EPB actuator to start an EPB disengagement control.
9 . The control method of claim 8 , wherein, when the detected actual hydraulic pressure is lower than the required hydraulic pressure, the starting of the EPB disengagement control comprises supplying the hydraulic pressure through an ESC actuator, until the detected actual hydraulic pressure reaches the required hydraulic pressure.
10 . The control method of claim 8 , wherein the starting of the EPB disengagement control comprises identifying the required hydraulic pressure according to a hydraulic pressure of the cylinder at a time of EPB engagement.
11 . The control method of claim 10 , further comprising:
in an EPB engagement, detecting the hydraulic pressure of the cylinder at the time of EPB engagement, and storing the detected hydraulic pressure of the cylinder in a memory.
12 . The control method of claim 11 , wherein the storing of the detected hydraulic pressure of the cylinder in the memory comprises storing the detected hydraulic pressure of the cylinder in the memory, when the detected hydraulic pressure of the cylinder is higher than a preset hydraulic pressure in the EPB engagement.
13 . The control method of claim 11 , wherein, when the detected hydraulic pressure of the cylinder is lower than a preset hydraulic pressure in the EPB engagement, the storing of the detected hydraulic pressure of the cylinder in the memory comprises supplying the hydraulic pressure through an ESC actuator, until the detected hydraulic pressure of the cylinder reaches the preset hydraulic pressure.