Patent Publication Number: US-2022227345-A1

Title: Electronic parking brake system and control method thereof

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is based on and claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2021-0006804, filed on Jan. 18, 2021, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety. 
     BACKGROUND 
     1. Field 
     The disclosure relates to an electronic parking brake system for operating an electronic parking brake provided on a wheel of a vehicle and operated by a motor, and a control method thereof. 
     2. Description of the Related Art 
     In general, an electronic parking brake system includes an electronic parking brake having a motor, and a controller for driving the electronic parking brake, and the controller drives the electronic parking brake to generate a fastening force required for parking. For example, the electronic parking brake system increases a torque generated from the motor through a reducer to generate a fastening force required for parking by a mechanical structure device inside a caliper. 
     However, a conventional electronic parking brake system may not efficiently operate an electronic front-wheel parking brake and an electronic rear-wheel parking brake according to a selection of a driver when a braking compensation function is required, such as when the driver presses a brake pedal, in case of an emergency situation such as failure of a braking system and deterioration of braking performance, when the braking system is in braking operation that brakes or stops a vehicle while driving, and in case of failure of one of the electronic parking brakes. 
     SUMMARY 
     It is an aspect of the disclosure to provide an electronic parking brake system capable of efficiently operating an electronic front-wheel parking brake and an electronic rear-wheel parking brake according to a selection of driver, and a control method thereof. 
     Additional aspects of the disclosure will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the disclosure. 
     In accordance with an aspect of the disclosure, an electronic parking brake system includes an electronic front-wheel parking brake provided on a front wheel side of a vehicle and configured to be operated by a front wheel motor, an electronic rear-wheel parking brake provided on a rear wheel side of the vehicle and configured to be operated by a rear wheel motor, a motor driving device configured to drive at least one of the front wheel motor and the rear wheel motor, and a controller electrically connected to the motor driving device, wherein the controller receives operation mode selection information in which an operation mode for operating at least one of the electronic front-wheel parking brake and the electronic rear-wheel parking brake is selected, and controls the motor driving device to operate at least one of the electronic front-wheel parking brake and the electronic rear-wheel parking brake in response to the operation mode of the received operation mode selection information. 
     The controller may receive the operation mode selection information when braking the vehicle while driving or stopping the vehicle. 
     The operation mode of the operation mode selection information may be a first operation mode for operating the electronic front-wheel parking brake and the electronic rear-wheel parking brake, a second operation mode for operating the electronic front-wheel parking brake, or a third operation mode for operating the electronic rear-wheel parking brake. 
     When the operation mode of the operation mode selection information is the first operation mode, the controller may control a first motor driving device and a second motor driving device for respectively driving the front wheel motor, and control a third motor driving device and a fourth motor driving device for respectively driving the rear wheel motor. 
     When the operation mode of the operation mode selection information is the second operation mode, the controller may control a first motor driving device and a second motor driving device for respectively driving the front wheel motor. 
     When the operation mode of the operation mode selection information is the third operation mode, the controller may control a third motor driving device and a fourth motor driving device for respectively driving the rear wheel motor. 
     When the operation mode of the operation mode selection information is the first operation mode, the controller may receive wiring harness wiring connection information for the first operation mode, control a first motor driving device and a second motor driving device for respectively driving the front wheel motor based on first wiring harness wiring connection information for driving the front wheel motor in the received wiring harness wiring connection information, and control a third motor driving device and a fourth motor driving device for respectively driving the rear wheel motor based on second wiring harness wiring connection information for driving the rear wheel motor in the received wiring harness wiring connection information. 
     When the operation mode of the operation mode selection information is the second operation mode, the controller may receive wiring harness wiring connection information for the second operation mode, and control a first motor driving device and a second motor driving device for respectively driving the front wheel motor based on first wiring harness wiring connection information for driving the front wheel motor in the received wiring harness wiring connection information. 
     When the operation mode of the operation mode selection information is the third operation mode, the controller may receive wiring harness wiring connection information for the third operation mode, and control a third motor driving device and a fourth motor driving device for respectively driving the rear wheel motor based on second wiring harness wiring connection information for driving the rear wheel motor in the received wiring harness wiring connection information. 
     The controller may control the motor driving device based on at least one of parking switch operation information, brake pedal operation information, and braking information. 
     The electronic parking brake system may further include an operation mode selector provided to allow an operation mode of the operation mode selection information to be selected by a driver. 
     The operation mode selector may include an all wheels parking (AWP) switch provided to select a first operation mode for operating the electronic front-wheel parking brake and the electronic rear-wheel parking brake together, a front wheel parking (FWP) switch provided to select a second operation mode for operating only the electronic front-wheel parking brake, and a rear wheel parking (RWP) switch provided to select a third operation mode for operating only the electronic rear-wheel parking brake. 
     In accordance with an aspect of the disclosure, a control method of an electronic parking brake system, which includes an electronic front-wheel parking brake provided on a front wheel side of a vehicle and configured to be operated by a front wheel motor, and an electronic rear-wheel parking brake provided on a rear wheel side of the vehicle and configured to be operated by a rear wheel motor, includes receiving operation mode selection information in which an operation mode for operating at least one of the electronic front-wheel parking brake and the electronic rear-wheel parking brake is selected, driving at least one of a front wheel motor of the electronic front-wheel parking brake and a rear wheel motor of the electronic rear-wheel parking brake in response to the operation mode of the received operation mode selection information, and operating at least one of the electronic front-wheel parking brake and the electronic rear-wheel parking brake by driving at least one of the front wheel motor and the rear wheel motor. 
     The receiving of the operation mode selection information may include receiving at least one of a first operation mode for operating the electronic front-wheel parking brake and the electronic rear-wheel parking brake together, a second operation mode for operating only the electronic front-wheel parking brake, and a third operation mode for operating only the electronic rear-wheel parking brake. 
     The driving of at least one of the front wheel motor and the rear wheel motor may include determining whether the operation mode of the received operation mode selection information is the first operation mode, and controlling a first motor driving device and a second motor driving device for respectively driving the front wheel motor and controlling a third motor driving device and a fourth motor driving device for respectively driving the rear wheel motor, when the operation mode is the first operation mode. 
     The driving of at least one of the front wheel motor and the rear wheel motor may include determining whether the operation mode of the received operation mode selection information is the second operation mode, and controlling a first motor driving device and a second motor driving device for respectively driving the front wheel motor when the operation mode is the second operation mode. 
     The driving of at least one of the front wheel motor and the rear wheel motor may include determining whether the operation mode of the received operation mode selection information is the third operation mode, and controlling a third motor driving device and a fourth motor driving device for respectively driving the rear wheel motor when the operation mode is the third operation mode. 
     The driving of at least one of the front wheel motor and the rear wheel motor may include determining whether the operation mode of the received operation mode selection information is the first operation mode, receiving wiring harness wiring connection information for the first operation mode when the operation mode is the first operation mode, controlling a first motor driving device and a second motor driving device for respectively driving the front wheel motor based on first wiring harness wiring connection information for driving the front wheel motor in the received wiring harness wiring connection information, and controlling a third motor driving device and a fourth motor driving device for respectively driving the rear wheel motor based on second wiring harness wiring connection information for driving the rear wheel motor in the received wiring harness wiring connection information. 
     The driving of at least one of the front wheel motor and the rear wheel motor may include determining whether the operation mode of the received operation mode selection information is the second operation mode, receiving wiring harness wiring connection information for the second operation mode when the operation mode is the second operation mode, and controlling a first motor driving device and a second motor driving device for respectively driving the front wheel motor based on first wiring harness wiring connection information for driving the front wheel motor in the received wiring harness wiring connection information. 
     The driving of at least one of the front wheel motor and the rear wheel motor may include determining whether the operation mode of the received operation mode selection information is the third operation mode, receiving wiring harness wiring connection information for the third operation mode when the operation mode is the third operation mode, and controlling a third motor driving device and a fourth motor driving device for respectively driving the rear wheel motor based on second wiring harness wiring connection information for driving the rear wheel motor in the received wiring harness wiring connection information. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other aspects of the disclosure will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which: 
         FIG. 1  illustrates a structure of an electronic parking brake included in an electronic parking brake system according to an embodiment; 
         FIG. 2  illustrates a configuration of the electronic parking brake system according to an embodiment; 
         FIG. 3  illustrates an operation mode selector installed in a vehicle to which the electronic parking brake system according to an embodiment is applied; 
         FIG. 4  illustrates a configuration of the operation mode selector illustrated in  FIG. 3 ; 
         FIG. 5  illustrates configurations of a motor driving device, a front wheel motor, and a rear wheel motor of the electronic parking brake system according to an embodiment; 
         FIG. 6  illustrates an example of a control method of the electronic parking brake system according to an embodiment; 
         FIG. 7  illustrates a method of driving at least one of the front wheel motor and the rear wheel motor in the electronic parking brake system according to an embodiment; 
         FIG. 8  illustrates, as an example, an operation of an electronic front-wheel parking brake and an electronic rear-wheel parking brake according to a first operation mode in the electronic parking brake system according to an embodiment; 
         FIG. 9  illustrates, as another example, an operation of the electronic front-wheel parking brake and the electronic rear-wheel parking brake according to the first operation mode in the electronic parking brake system according to an embodiment; 
         FIG. 10  illustrates, as an example, an operation of the electronic front-wheel parking brake according to a second operation mode in the electronic parking brake system according to an embodiment; 
         FIG. 11  illustrates, as another example, an operation of the electronic front-wheel parking brake according to the second operation mode in the electronic parking brake system according to an embodiment; 
         FIG. 12  illustrates, as an example, an operation of the electronic rear-wheel parking brake according to a third operation mode in the electronic parking brake system according to an embodiment; and 
         FIG. 13  illustrates, as another example, an operation of the electronic rear-wheel parking brake according to the third operation mode in the electronic parking brake system according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Like reference numerals refer to like elements throughout the specification. This specification does not describe all the elements of the embodiments, and duplicative contents between general contents or embodiments in the technical field of the present disclosure will be omitted. The terms ‘part,’ ‘module,’ ‘member,’ and ‘block’ used in this specification may be embodied as software or hardware, and it is also possible for a plurality of ‘parts,’ ‘modules,’ ‘members,’ and ‘blocks’ to be embodied as one component, or one ‘part,’ ‘module,’ ‘member,’ and ‘block’ to include a plurality of components according to embodiments. 
     Throughout the specification, when a part is referred to as being “connected” to another part, it includes not only a direct connection but also an indirect connection, and the indirect connection includes connecting through a wireless network. 
     Also, when it is described that a part “includes” an element, it means that the element may further include other elements, not excluding the other elements unless specifically stated otherwise. 
     Throughout the specification, when a member is described as being “on” another member, this includes not only a case in which a member is in contact with another member but also a case in which another member is present between the two members. 
     The terms ‘first,’ ‘second,’ etc. are used to distinguish one element from another element, and the elements are not limited by the above-mentioned terms. The singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. 
     In each step, an identification numeral is used for convenience of explanation, the identification numeral does not describe the order of the steps, and each step may be performed differently from the order specified unless the context clearly states a particular order. 
       FIG. 1  illustrates a structure of an electronic parking brake included in an electronic parking brake system according to an embodiment. 
     Referring to  FIG. 1 , an electronic parking brake  100  may include a carrier  110  on which a pair of pad plates  111  and  112  are installed to move forward or backward to press a brake disc D rotating together with a wheel of a vehicle, a caliper housing  120  provided with a cylinder  123  slidably installed on the carrier  110  and in which a piston  121  is installed to move forward or backward by a braking hydraulic pressure, a power conversion unit  130  to press the piston  121 , and an actuator  140  to transmit a rotational force to the power conversion unit  130  using a motor  141 . 
     The pair of pad plates  111  and  112  may be divided into the inner pad plate  111  disposed to be in contact with the piston  121  and the outer pad plate  112  disposed to be in contact with a finger part  122  of the caliper housing  120 . The pair of pad plates  111  and  112  are installed on the carrier  110  fixed to a vehicle body so as to move forward or backward toward both sides of the brake disk D. In addition, a brake pad  113  may be attached to one surface of each of the pad plates  111  and  112  facing the brake disk D. 
     The caliper housing  120  may be slidably installed on the carrier  110 . More specifically, the caliper housing  120  may include the cylinder  123  in which the power conversion unit  130  is installed at a rear portion thereof and the piston  121  moves forward or backward therein, and the finger part  122  formed in a front portion thereof to be bent in a downward direction so as to operate the outer pad plate  112 . The finger part  122  and the cylinder  123  may be formed integrally. 
     The piston  121  may be provided in a cylindrical shape in which the inside thereof is recessed in a cup shape to be slidably inserted into the cylinder  123 . The piston  121  may press the inner pad plate  111  to the brake disk D side by an axial force of the power conversion unit  130  receiving the rotational force of the EPB (electronic parking brake) actuator  140 . Accordingly, when the axial force of the power conversion unit  130  is applied, the piston  121  moves forward to the inner pad plate  111  side to press the inner pad plate  111 , and the caliper housing  120  operates in a direction opposite to the piston  121  by a reaction force so that the finger part  122  presses the outer pad plate  112  to the brake disk D side, thereby performing braking. 
     The power conversion unit  130  may perform a function of pressing the piston  121  toward the inner pad plate  111  by receiving the rotational force from the motor actuator  140 . 
     The power conversion unit  130  may include a nut member  131  installed in the piston  121  to be in contact with the piston  121 , and a spindle member  135  screwed to the nut member  131 . 
     The nut member  131  may be disposed in the piston  121  in a state in which a rotation thereof is restricted to be screwed to the spindle member  135 . 
     The nut member  131  may be formed by a head part  132  provided to be in contact with the piston  121 , and a coupling part  133  formed extending from the head part  132  and having a female thread formed on an inner circumferential surface thereof to be screwed to the spindle member  135 . 
     The nut member  131  may perform a function of pressing or releasing the piston  121  by moving in an advance direction or a reverse direction depending on a rotation direction of the spindle member  135 . In this case, the advance direction may be a direction in which the nut member  131  moves to approach the piston  121 . The reverse direction may be a direction in which the nut member  131  moves away from the piston  121 . In addition, the advance direction may be a direction in which the piston  121  moves to approach the brake pad  113 . The reverse direction may be a direction in which the piston  121  moves away from the brake pad  113 . 
     The spindle member  135  may include a shaft part  136  penetrating the rear portion of the caliper housing  120  to rotate by receiving the rotational force of the EPB actuator  140 , and a flange part  137  formed to extend in a radial direction from the shaft part  136 . One side of the shaft part  136  may be rotatably installed to penetrate a rear side of the cylinder  123 , and the other side of the shaft part  136  may be disposed in the piston  121 . In this case, one side of the shaft part  136  penetrating the cylinder  123  is connected to an output shaft of a reducer  142  to receive the rotational force of the actuator  140 . 
     The actuator  140  may include the motor  141  and the reducer  142 . 
     The motor  141  may press or release the piston  121  by moving the nut member  131  forward or backward by rotating the spindle member  135 . 
     The reducer  142  may be provided between the output side of the motor  141  and the spindle member  135 . 
     By having the above configuration, the electronic parking brake  100  may move the nut member  131  to press the piston  121  by rotating the spindle member  135  in one direction using the actuator  140  in a parking operation mode. The piston  121  pressed by the movement of the nut member  131  presses the inner pad plate  111  to bring the brake pad  113  into close contact with the brake disk D, thereby generating a clamping force. 
     In addition, the electronic parking brake  100  rotates the spindle member  135  in the opposite direction using the motor actuator  140  in a parking release mode, so that the nut member  131  pressed against the piston  121  may move backward. The pressure applied to the piston  121  may be released by the backward movement of the nut member  131 . As the pressure applied to the piston  121  is released, the brake pad  113  may be spaced apart from the brake disk D, thereby releasing the generated clamping force. 
       FIG. 2  illustrates a configuration of the electronic parking brake system according to an embodiment. 
     Referring to  FIG. 2 , an electronic parking brake system  200  may include a front wheel motor  141   a , a rear wheel motor  141   b , a motor driving device  210 , and a controller  220 . The controller  220  may receive operation mode selection information when braking the vehicle while driving or when stopping the vehicle. 
       FIG. 3  illustrates an operation mode selector installed in a vehicle to which the electronic parking brake system according to an embodiment is applied. 
     Referring to  FIG. 3 , an operation mode selector  10  may be installed on the center fascia CP provided inside the vehicle. The operation mode selector  10  may be provided to select an operation mode for operating at least one of an electronic front-wheel parking brake provided on a front wheel side and an electronic rear-wheel parking brake provided on a rear wheel side. The operation mode selector  10  is not limited thereto, and may be provided as a separate type switch inside the vehicle. 
     The operation mode selector  10  may be provided to select the operation mode when braking a vehicle  1  while driving or stopping the vehicle  1 . For example, the operation mode selector  10  may select the operation mode when a braking compensation function is required for an operation of a brake pedal of a driver, and transmit brake pedal operation information to the controller  220  in response to the selected operation mode. The operation mode selector  10  may select the operation mode when the braking compensation function is required for an emergency situation such as failure of the braking system and deterioration of braking performance, and transmit braking information to the controller  220  in response to the selected operation mode. The operation mode selector  10  may select the operation mode when the braking compensation function is required for the braking performance of the braking system that brakes or stops during driving, and transmit the braking information to the controller  220  in response to the selected operation mode. The braking system may be an electro-hydraulic braking device, an integrated dynamic brake (IDB), an anti-lock braking system (ABS), an electronic stability control (ESC), a traction control system (TCS), or the like. 
       FIG. 4  illustrates a configuration of the operation mode selector illustrated in  FIG. 3 . 
     Referring to  FIG. 4 , the operation mode selector  10  may include an all wheels parking (AWP) switch  11  provided to select a first operation mode for operating the electronic front-wheel parking brake and the electronic rear-wheel parking brake, a front wheel parking (FWP) switch  12  provided to select a second operation mode for operating the electronic front-wheel parking brake, and a rear wheel parking (RWP) switch  13  provided to select a third operation mode for operating the electronic rear-wheel parking brake. The AWP switch  11 , the FWP switch  12 , and the RWP switch  13  may transmit a first switch signal for the first operation mode, a second switch signal for the second operation mode, or a third switch signal for the third operation mode to the controller  220  according to a selection of the driver. The operation mode selector  10  may be provided to select any one of an AWP display window, a FWP display window, and a RWP display window, which are displayed through a display panel  14  of the center fascia CP, instead of the AWP switch  11 , the FWP switch  12 , and the RWP switch  13 . 
       FIG. 5  illustrates configurations of a motor driving device, a front wheel motor, and a rear wheel motor of the electronic parking brake system according to an embodiment. 
     Referring to  FIG. 5 , the motor driving device  210  may drive at least one of the front wheel motor  141   a  and the rear wheel motor  141   b . The motor driving device  210  may include a first motor driving device  211 , a second motor driving device  212 , a third motor driving device  213 , and a fourth motor driving device  214 . The front wheel motor  141   a  may be provided in the electronic front-wheel parking brake provided on the front wheel side. The front wheel motor  141   a  may include a front right wheel motor  141   a   1  and a front left wheel motor  141   a   2 . The front right wheel motor  141   a   1  may be driven by the first motor driving device  211 , and the front left wheel motor  141   a   2  may be driven by the second motor driving device  212 . The rear wheel motor  141   b  may be provided in the electronic rear-wheel parking brake provided on the rear wheel side. The rear wheel motor  141   b  may include a rear right wheel motor  141   b   1  and a rear left wheel motor  141   b   2 . The rear right wheel motor  141   b   1  may be driven by the third motor driving device  213 , and the rear left wheel motor  141   b   2  may be driven by the fourth motor driving device  214 . 
     The motor driving device  210  may drive the front wheel motor  141   a  and the rear wheel motor  141   b  in a forward rotation direction or a reverse rotation direction. For example, the motor driving device  210  may include an H-bridge circuit including a plurality of power switching devices to drive the front wheel motor  141   a  and the rear wheel motor  141   b  in the forward rotation direction or the reverse rotation direction. 
     The controller  220  may perform the parking operation mode or the parking release mode according to an operation signal of a parking switch operated by the driver or an operation signal generated by a program related to an operation of the electronic parking brake. 
     The controller  220  may press the piston  121  by moving the nut member  131  in the advance direction by rotating at least one of the front wheel motor  141   a  and the rear wheel motor  141   b  in one direction in the parking operation mode, thereby performing a parking operation (Apply) in which the brake pad  113  is brought into close contact with the brake disk D to generate a clamping force. 
     The controller  220  may release the piston  121  by moving the nut member  131  in the reverse direction by rotating at least one of the front wheel motor  141   a  and the rear wheel motor  141   b  in the opposite direction in the parking release mode, thereby performing a parking release (Release) in which the brake pad  113  being into close contact with the brake disk D is released to release the generated clamping force. 
     The electronic parking brake system  200  according to an embodiment allows the driver to select the operation mode for operating at least one of the electronic front-wheel parking brake and the electronic rear-wheel parking brake, so that the electronic front-wheel parking brake and the electronic rear-wheel parking brake are effectively operated according to a selection of the driver. 
     The controller  220  may include a processor  221  and a memory  222 . 
     The processor  221  may control the motor driving device  210  to operate at least one of the electronic front-wheel parking brake and the electronic rear-wheel parking brake in response to the operation mode of the received operation mode selection information. The operation mode selector  10  may output the operation mode selection information including the first operation mode for operating the electronic front-wheel parking brake and the electronic rear-wheel parking brake, the second operation mode for operating the electronic front-wheel parking brake, or the third operation mode for operating the electronic rear-wheel parking brake. 
     When the received operation mode is the first operation mode, the processor  221  may control the first motor driving device  211  and the second motor driving device  212  for respectively driving the front wheel motor  141   a , and may control the third motor driving device  213  and the fourth motor driving device  214  for respectively driving the rear wheel motor  141   b . The first motor driving device  211  may drive the front right wheel motor  141   a   1 , the second motor driving device  212  may drive the front left wheel motor  141   a   2 , the third motor driving device  213  may drive the rear right wheel motor  141   b   1 , and the fourth motor driving device  214  may drive the rear left wheel motor  141   b   2 . 
     When the received operation mode is the second operation mode, the processor  221  may control the first motor driving device  211  and the second motor driving device  212  for respectively driving the front wheel motor  141   a . The first motor driving device  211  may drive the front right wheel motor  141   a   1 , the second motor driving device  212  may drive the front left wheel motor  141   a   2 . 
     When the received operation mode is the third operation mode, the processor  221  may control the third motor driving device  213  and the fourth motor driving device  214  for respectively driving the rear wheel motor  141   b . The third motor driving device  213  may drive the rear right wheel motor  141   b   1 , and the fourth motor driving device  214  may drive the rear left wheel motor  141   b   2 . 
     When the received operation mode is the first operation mode, the processor  221  may receive wiring harness wiring connection information for the first operation mode. For example, the processor  221  may request the wiring harness wiring connection information for the first operation mode from a smart junction box (SJB) controller to control a smart junction box. The smart junction box uses an intelligent power switch (IPS), which is a semiconductor device having the same function as a fuse and a relay, so that the smart junction box may be reduced in size and weight compared to a conventional junction box. The smart junction box (SJB) controller is increasingly being integrated into a body control module (BCM). 
     The smart junction box may be electrically connected to the first motor driving device  211  for driving the front right wheel motor  141   a   1 , the second motor driving device  212  for driving the front left wheel motor  141   a   2 , the third motor driving device  213  for driving the rear right wheel motor  141   b   1 , and the fourth motor driving device  214  for driving the rear left wheel motor  141   b   2 , through a wiring harness. 
     Such the SJB controller or BCM may improve vehicle stability with various failure monitoring functions and failure diagnosis functions. The SJB controller or BCM may monitor and diagnose an electrical connection state with each of the motor driving devices  211  to  214  through the processor and transmit each wiring harness wiring connection information for each of the operation modes to the controller  220 . When an abnormal electrical connection state exists among the electrical connection states with the motor driving devices  211  to  214 , the SJB controller or BCM may transmit wiring harness wiring connection information for the abnormal electrical connection state to the controller  220 . When an abnormal electrical connection state exists among the electrical connection states with the motor driving devices  211  to  214 , the SJB controller or BCM may adjust a wiring connection of the wiring harness for a normal electrical connection, and may transmit wiring harness wiring connection information for the normal electrical connection state to the controller  220  when the normal electrical connection is achieved through the adjusted wiring connection of the wiring harness. Instead of the SJB controller or BCM, each ECU for controlling the braking system (ABS, ESC, IDB, etc.) may directly perform a function of changing the wiring connection of the wiring harness. 
     The processor  221  may control the first motor driving device  211  and the second motor driving device  212  for respectively driving the front wheel motor  141   a  based on first wiring harness wiring connection information for driving the front wheel motor  141   a  in the received wiring harness wiring connection information. The processor  221  may identify the first wiring harness wiring connection information for the first operation mode and recognize the electrical connection state with the first motor driving device  211  and the electrical connection state with the second motor driving device  212 . When the electrical connection state with the first motor driving device  211  and the electrical connection state with the second motor driving device  212  are normal, the processor  221  may control the first motor driving device  211  and the second motor driving device  212  for respectively driving the front wheel motor  141   a . The first motor driving device  211  may drive the front right wheel motor  141   a   1 , and the second motor driving device  212  may drive the front left wheel motor  141   a   2 . 
     The processor  221  may control the third motor driving device  213  and the fourth motor driving device  214  for respectively driving the rear wheel motor  141   b  based on second wiring harness wiring connection information for driving the rear wheel motor  141   b  in the received wiring harness wiring connection information. The processor  221  may identify the second wiring harness wiring connection information for the first operation mode and recognize the electrical connection state with the third motor driving device  213  and the electrical connection state with the fourth motor driving device  214 . When the electrical connection state with the third motor driving device  213  and the electrical connection state with the fourth motor driving device  214  are normal, the processor  221  may control the third motor driving device  213  and the fourth motor driving device  214  for respectively driving the rear wheel motor  141   b . The third motor driving device  213  may drive the rear right wheel motor  141   b   1 , and the fourth motor driving device  214  may drive the rear left wheel motor  141   b   2 . 
     When the received operation mode is the second operation mode, the processor  221  may receive wiring harness wiring connection information for the second operation mode. The processor  221  may control the first motor driving device  211  and the second motor driving device  212  for respectively driving the front wheel motor  141   a  based on the first wiring harness wiring connection information for driving the front wheel motor  141   a  in the received wiring harness wiring connection information. The processor  221  may identify the first wiring harness wiring connection information for the second operation mode and recognize the electrical connection state with the first motor driving device  211  and the electrical connection state with the second motor driving device  212 . When the electrical connection state with the first motor driving device  211  and the electrical connection state with the second motor driving device  212  are normal, the processor  221  may control the first motor driving device  211  and the second motor driving device  212  for respectively driving the front wheel motor  141   a . The first motor driving device  211  may drive the front right wheel motor  141   a   1 , and the second motor driving device  212  may drive the front left wheel motor  141   a   2 . 
     When the received operation mode is the third operation mode, the processor  221  may receive wiring harness wiring connection information for the third operation mode. The processor  221  may control the third motor driving device  213  and the fourth motor driving device  214  for respectively driving the rear wheel motor  141   b  based on the second wiring harness wiring connection information for driving the rear wheel motor  141   b  in the received wiring harness wiring connection information. The processor  221  may identify the second wiring harness wiring connection information for the third operation mode and recognize the electrical connection state with the third motor driving device  213  and the electrical connection state with the fourth motor driving device  214 . When the electrical connection state with the third motor driving device  213  and the electrical connection state with the fourth motor driving device  214  are normal, the processor  221  may control the third motor driving device  213  and the fourth motor driving device  214  for respectively driving the rear wheel motor  141   b . The third motor driving device  213  may drive the rear right wheel motor  141   b   1 , and the fourth motor driving device  214  may drive the rear left wheel motor  141   b   2 . 
     The processor  221  may control the motor driving device  210  that drives at least one of the front wheel motor  141   a  and the rear wheel motor  141   b  based on at least one of the received parking switch operation information, brake pedal operation information, and braking information. In a situation where the processor  221  may receive the parking switch operation information and operate at least one of the electronic front-wheel parking brake and the electronic rear-wheel parking brake, the processor  221  may control the motor driving device  210  that drives at least one of the front wheel motor  141   a  and the rear wheel motor  141   b  to perform the braking compensation function, based on at least one of the brake pedal operation information and the braking information according to the selected operation mode. 
     The processor  221  may receive the parking switch operation information from the parking switch. The processor  221  may receive the brake pedal operation information from a brake pedal position sensor, and may receive the brake pedal operation information input or estimated from another system that performs CAN communication, which is an in-vehicle network, on behalf of the brake pedal position sensor. The processor  221  may receive the braking information input or estimated from a braking system performing CAN communication. 
     The processor  221  may include a signal processor for processing an operation mode selection signal, the wiring harness wiring connection information, the parking switch operation information, the brake pedal operation information, and the braking information, and a micro control unit (MCU) for generating a motor drive signal for actuating or deactivating the electronic parking brake  100 . 
     The memory  222  may store a program and/or data for the processor  221  to process the operation mode selection signal, the wiring harness wiring connection information, the parking switch operation information, the brake pedal operation information, and the braking information, and a program and/or data for the processor  221  to generate the motor drive signal for actuating or deactivating the electronic parking brake  100 . 
     The memory  222  may temporarily store the operation mode selection signal, the wiring harness wiring connection information, the parking switch operation information, the brake pedal operation information, and the braking information, and may temporarily store the result of processing the operation mode selection signal, the wiring harness wiring connection information, the parking switch operation information, the brake pedal operation information, and the braking information of the processor  221 . 
     The memory  222  may include a non-volatile memory such as flash memory, read only memory (ROM), and erasable programmable read only memory (EPROM) as well as a volatile memory such as S-RAM and D-RAM. 
       FIG. 6  illustrates an example of a control method of the electronic parking brake system according to an embodiment. 
     Referring to  FIG. 6 , the controller  220  may receive the operation mode selection information for operating at least one of the electronic front-wheel parking brake and the electronic rear-wheel parking brake ( 610 ). The operation mode selector  10  may select the operation mode for operating at least one of the electronic front-wheel parking brake and the electronic rear-wheel parking brake. The operation mode selector  10  may select the first operation mode for operating the electronic front-wheel parking brake and the electronic rear-wheel parking brake, the second operation mode for operating the electronic front-wheel parking brake, or the third operation mode for operating the electronic rear-wheel parking brake. The AWP switch  11  may transmit the first switch signal for the first operation mode to the controller  220 , the FWP switch  12  may transmit the second switch signal for the second operation mode to the controller  220 , and the RWP switch  13  may transmit the third switch signal for the third operation mode to the controller  220 . 
     The controller  220  may drive at least one of the front wheel motor  141   a  of the electronic front-wheel parking brake and the rear wheel motor  141   b  of the electronic rear-wheel parking brake in response to the operation mode of the received operation mode selection information ( 620 ). 
       FIG. 7  illustrates a method of driving at least one of the front wheel motor and the rear wheel motor in the electronic parking brake system according to an embodiment. 
     Referring to  FIG. 7 , the controller  220  may determine whether the operation mode of the received operation mode selection information is the first operation mode ( 621 ). When the first switch signal for the first operation mode is received, the controller  220  may determine that the driver selects the AWP switch  11 . 
     When the operation mode of the received operation mode selection information is the first operation mode, the controller  220  may control the first motor driving device  211  and the second motor driving device  212  for respectively driving the front right wheel motor  141   a   1  and the front left wheel motor  141   a   2 , and may control the third motor driving device  213  and the fourth motor driving device  214  for respectively driving the rear right wheel motor  141   b   1  and the rear left wheel motor  141   b   2  ( 622 ). 
     When the operation mode of the received operation mode selection information is the first operation mode, the controller  220  may receive the wiring harness wiring connection information for the first operation mode. 
     Thereafter, the controller  220  may receive the first wiring harness wiring connection information for driving the front wheel motor  141   a  and the second wiring harness wiring connection information for driving the rear wheel motor  141   b  in the received wiring harness wiring connection information. 
     Thereafter, the controller  220  may control the first motor driving device  211  and the second motor driving device  212  for respectively driving the front right wheel motor  141   a   1  and the front left wheel motor  141   a   2  when the electrical connection state with the first motor driving device  211  and the electrical connection state with the second motor driving device  212  are normal based on the received first wiring harness wiring connection information, and may control the third motor driving device  213  and the fourth motor driving device  214  for respectively driving the rear right wheel motor  141   b   1  and the rear left wheel motor  141   b   2  when the electrical connection state with the third motor driving device  213  and the electrical connection state with the fourth motor driving device  214  are normal based on the received second wiring harness wiring connection information ( 622 ). 
     When it is not the first operation mode as a result of the determination in the operation mode  621 , the controller  220  may determine whether the operation mode of the received operation mode selection information is the second operation mode ( 623 ). When the second switch signal for the second operation mode is received, the controller  220  may determine that the driver selects the FWP switch  12 . 
     When the operation mode of the received operation mode selection information is the second operation mode, the controller  220  may control the first motor driving device  211  and the second motor driving device  212  for respectively driving the front right wheel motor  141   a   1  and the front left wheel motor  141   a   2  ( 624 ). 
     When the operation mode of the received operation mode selection information is the second operation mode, the controller  220  may receive the wiring harness wiring connection information for the second operation mode. 
     Thereafter, the controller  220  may receive the first wiring harness wiring connection information for driving the front wheel motor  141   a  in the received wiring harness wiring connection information. 
     Thereafter, when the electrical connection state with the first motor driving device  211  and the electrical connection state with the second motor driving device  212  are normal based on the received first wiring harness wiring connection information, the controller  220  may control the first motor driving device  211  and the second motor driving device  212  for respectively driving the front right wheel motor  141   a   1  and the front left wheel motor  141   a   2  ( 624 ). 
     When it is not the second operation mode as a result of the determination in the operation mode  623 , the controller  220  may determine whether the operation mode of the received operation mode selection information is the third operation mode ( 625 ). When the third switch signal for the third operation mode is received, the controller  220  may determine that the driver selects the RWP switch  13 . 
     When the operation mode of the received operation mode selection information is the third operation mode, the controller  220  may control the third motor driving device  213  and the fourth motor driving device  214  for respectively driving the rear right wheel motor  141   b   1  and the rear left wheel motor  141   b   2  ( 626 ). 
     When the operation mode of the received operation mode selection information is the third operation mode, the controller  220  may receive the wiring harness wiring connection information for the third operation mode. 
     Thereafter, the controller  220  may receive the second wiring harness wiring connection information for driving the rear wheel motor  141   b  in the received wiring harness wiring connection information. 
     Thereafter, when the electrical connection state with the third motor driving device  213  and the electrical connection state with the fourth motor driving device  214  are normal based on the received second wiring harness wiring connection information, the controller  220  may control the third motor driving device  213  and the fourth motor driving device  214  for respectively driving the rear right wheel motor  141   b   1  and the rear left wheel motor  141   b   2  ( 626 ). 
     When it is not the third operation mode as a result of the determination in the operation mode  625 , the controller  220  may determine that the driver does not select the operation mode selector  10 . The controller  220  may determine that the driver does not select the AWP switch  11 , the FWP switch  12 , or the RWP switch  13 . 
     The controller  220  may operate at least one of the electronic front-wheel parking brake and the electronic rear-wheel parking brake by driving at least one of the front-wheel motor  141   a  and the rear-wheel motor  141   b  ( 630 ). 
       FIG. 8  illustrates, as an example, an operation of an electronic front-wheel parking brake and an electronic rear-wheel parking brake according to a first operation mode in the electronic parking brake system according to an embodiment. 
     Referring to  FIG. 8 , when the operation mode of the received operation mode selection information is the first operation mode, the controller  220  may transmit a driving command to the first motor driving device  211 , the second motor driving device  212 , the third motor driving device  213 , and the fourth motor driving device  214  to rotationally drive the front right wheel motor  141   a   1 , the front left wheel motor  141   a   2 , the rear right wheel motor  141   b   1 , and the rear left wheel motor  141   b   2  in an operation direction so as to operate electronic front-wheel parking brakes  100   a  and  100   b  and electronic rear-wheel parking brakes  100   c  and  100   d.    
     The first motor driving device  211 , the second motor driving device  212 , the third motor driving device  213 , and the fourth motor driving device  214  may rotationally drive the front right wheel motor  141   a   1 , the front left wheel motor  141   a   2 , the rear right wheel motor  141   b   1 , and the rear left wheel motor  141   b   2  in the operation direction to perform the braking compensation function based on at least one of the brake pedal operation information and the braking information according to the selected first operation mode. 
     The electronic front-wheel parking brakes  100   a  and  100   b  and the electronic rear-wheel parking brakes  100   c  and  100   d  may generate a clamping force necessary for braking the vehicle  1  while driving or for stopping the vehicle  1  by driving the front right wheel motor  141   a   1 , the front left wheel motor  141   a   2 , the rear right motor  141   b   1 , and the rear left motor  141   b   2 . 
       FIG. 9  illustrates, as another example, an operation of the electronic front-wheel parking brake and the electronic rear-wheel parking brake according to the first operation mode in the electronic parking brake system according to an embodiment. 
     Referring to  FIG. 9 , when the operation mode of the received operation mode selection information is the first operation mode, the controller  220  may receive the wiring harness wiring connection information for the first operation mode. 
     Thereafter, when the electrical connection state with the first motor driving device  211 , the electrical connection state with the second motor driving device  212 , the electrical connection state with the third motor driving device  213 , and the electrical connection state with the fourth motor driving device  214  are normal based on the first wiring harness wiring connection information and the second wiring harness wiring connection information for driving the front wheel motor  141   a  and the rear wheel motor  141   b  in the received wiring harness wiring connection information, the controller  220  may transmit a driving command to the first motor driving device  211 , the second motor driving device  212 , the third motor driving device  213 , and the fourth motor driving device  214  to rotationally drive the front right wheel motor  141   a   1 , the front left wheel motor  141   a   2 , the rear right wheel motor  141   b   1 , and the rear left wheel motor  141   b   2  in the operation direction so as to operate the electronic front-wheel parking brakes  100   a  and  100   b  and the electronic rear-wheel parking brakes  100   c  and  100   d.    
     The first motor driving device  211 , the second motor driving device  212 , the third motor driving device  213 , and the fourth motor driving device  214  may rotationally drive the front right wheel motor  141   a   1 , the front left wheel motor  141   a   2 , the rear right wheel motor  141   b   1 , and the rear left wheel motor  141   b   2  in the operation direction to perform the braking compensation function based on at least one of the brake pedal operation information and the braking information according to the selected first operation mode. 
     The electronic front-wheel parking brakes  100   a  and  100   b  and the electronic rear-wheel parking brakes  100   c  and  100   d  may generate a clamping force necessary for braking the vehicle  1  while driving or for stopping the vehicle  1  by driving the front right wheel motor  141   a   1 , the front left wheel motor  141   a   2 , the rear right motor  141   b   1 , and the rear left motor  141   b   2 . 
       FIG. 10  illustrates, as an example, an operation of the electronic front-wheel parking brake according to a second operation mode in the electronic parking brake system according to an embodiment. 
     Referring to  FIG. 10 , when the operation mode of the received operation mode selection information is the second operation mode, the controller  220  may transmit a driving command to the first motor driving device  211  and the second motor driving device  212  to rotationally drive the front right wheel motor  141   a   1  and the front left wheel motor  141   a   2  in the operation direction so as to operate the electronic front-wheel parking brakes  100   a  and  100   b.    
     The first motor driving device  211  and the second motor driving device  212  may rotationally drive the front right wheel motor  141   a   1  and the front left wheel motor  141   a   2  in the operation direction to perform the braking compensation function based on at least one of the brake pedal operation information and the braking information according to the selected second operation mode. 
     The electronic front-wheel parking brakes  100   a  and  100   b  may generate a clamping force necessary for stopping the vehicle  1  by driving the front right wheel motor  141   a   1  and the front left wheel motor  141   a   2 . 
       FIG. 11  illustrates, as another example, an operation of the electronic front-wheel parking brake according to the second operation mode in the electronic parking brake system according to an embodiment. 
     Referring to  FIG. 11 , when the operation mode of the received operation mode selection information is the second operation mode, the controller  220  may receive the wiring harness wiring connection information for the second operation mode. 
     Thereafter, when the electrical connection state with the first motor driving device  211  and the electrical connection state with the second motor driving device  212  are normal based on the first wiring harness wiring connection information for driving the front wheel motor  141   a  in the received wiring harness wiring connection information, the controller  220  may transmit a driving command to the first motor driving device  211  and the second motor driving device  212  to rotationally drive the front right wheel motor  141   a   1  and the front left wheel motor  141   a   2  in the operation direction so as to operate the electronic front-wheel parking brakes  100   a  and  100   b.    
     The first motor driving device  211  and the second motor driving device  212  may rotationally drive the front right wheel motor  141   a   1  and the front left wheel motor  141   a   2  in the operation direction to perform the braking compensation function based on at least one of the brake pedal operation information and the braking information according to the selected second operation mode. 
     The electronic front-wheel parking brakes  100   a  and  100   b  may generate a clamping force necessary for braking the vehicle  1  while driving or for stopping the vehicle  1  by driving the front right wheel motor  141   a   1  and the front left wheel motor  141   a   2 . 
       FIG. 12  illustrates, as an example, an operation of the electronic rear-wheel parking brake according to a third operation mode in the electronic parking brake system according to an embodiment. 
     Referring to  FIG. 12 , when the operation mode of the received operation mode selection information is the third operation mode, the controller  220  may transmit a driving command to the third motor driving device  213  and the fourth motor driving device  214  to rotationally drive the rear right wheel motor  141   b   1  and the rear left wheel motor  141   b   2  in the operation direction so as to operate the electronic rear-wheel parking brakes  100   c  and  100   d.    
     The third motor driving device  213  and the fourth motor driving device  214  may rotationally drive the rear right wheel motor  141   b   1  and the rear left wheel motor  141   b   2  in the operation direction to perform the braking compensation function based on at least one of the brake pedal operation information and the braking information according to the selected third operation mode. 
     The electronic rear-wheel parking brakes  100   c  and  100   d  may generate a clamping force necessary for braking the vehicle  1  while driving or for stopping the vehicle  1  by driving the rear right wheel motor  141   b   1  and the rear left wheel motor  141   b   2 . 
       FIG. 13  illustrates, as another example, an operation of the electronic rear-wheel parking brake according to the third operation mode in the electronic parking brake system according to an embodiment. 
     Referring to  FIG. 13 , when the operation mode of the received operation mode selection information is the third operation mode, the controller  220  may receive the wiring harness wiring connection information for the third operation mode. 
     Thereafter, when the electrical connection state with the third motor driving device  213  and the electrical connection state with the fourth motor driving device  214  are normal based on the second wiring harness wiring connection information for driving the rear wheel motor  141   b  in the received wiring harness wiring connection information, the controller  220  may transmit a driving command to the third motor driving device  213  and the fourth motor driving device  214  to rotationally drive the rear right wheel motor  141   b   1  and the rear left wheel motor  141   b   2  in the operation direction so as to operate the electronic rear-wheel parking brakes  100   c  and  100   d.    
     The third motor driving device  213  and the fourth motor driving device  214  may rotationally drive the rear right wheel motor  141   b   1  and the rear left wheel motor  141   b   2  in the operation direction to perform the braking compensation function based on at least one of the brake pedal operation information and the braking information according to the selected third operation mode. 
     The electronic rear-wheel parking brakes  100   c  and  100   d  may generate a clamping force necessary for braking the vehicle  1  while driving or for stopping the vehicle  1  by driving the rear right wheel motor  141   b   1  and the rear left wheel motor  141   b   2 . 
     As described above, the electronic parking brake system  200  according to an embodiment may allow the driver to select the operation of the electronic front-wheel parking brake and the operation of the electronic rear-wheel parking brake when the braking compensation function is required for the operation of the brake pedal of the driver, when the brake compensation function is required for an emergency situation such as failure of the brake system and deterioration of brake performance, when the brake compensation function is required for the braking performance of the braking system that brakes or stops while driving, and when the brake compensation function is required for the failure of the electronic parking brake on one side, thereby efficiently operating the electronic front-wheel parking brake and the electronic rear-wheel parking brake according to a selection of the driver. 
     As is apparent from the above, according to one aspect of the disclosure, an electronic front-wheel parking brake and an electronic rear-wheel parking brake can be efficiently operated according to a selection of a driver.