120 according to an embodiment of the present disclosure may reduce the change in acceleration of the vehicle, in particular, the change in the longitudinal acceleration, when accelerating in the low-speed driving situation, thereby preventing the driver and the passenger in the vehicle from experiencing motion sickness.

Referring back to FIG. 1, as described above, the controller 120 may control the longitudinal acceleration of the vehicle to be limited when the vehicle accelerates in the low-speed driving situation. However, when the longitudinal acceleration is continuously controlled to be limited, the vehicle may not accelerate when acceleration is required. To this end, the controller 120 according to embodiments of the present disclosure may control the longitudinal acceleration of the vehicle to be limited based on the varied longitudinal limit acceleration until the vehicle's speed exceeds the predetermined first reference speed. That is, when the vehicle's speed exceeds the predetermined first reference speed, the controller 120 may stop controlling the vehicle's longitudinal acceleration to be limited.

Next, when a brake-pedal position sensor (BPS) receives an input in the low-speed driving situation where the vehicle speed is less than a preset first reference speed, the controller 120 may determine that the vehicle decelerates in the low-speed driving situation. To this end, the controller 120 may receive information about the presence or absence of the input from the brake-pedal position sensor in low-speed driving situations of the vehicle. Then, the controller 120 may determine a deceleration demand torque based on a sensing value of the brake-pedal position sensor. The controller 120 may compare the determined deceleration demand torque to a predetermined reference torque to determine whether to perform deceleration-related control in the low-speed driving situation of the vehicle. In this case, the predetermined reference torque may be a value configured to correspond to a reference sensing value (e.g., 50%) of the brake-pedal position sensor. However, this is illustrative and the present disclosure is not necessarily limited thereto.

For example, when the determined deceleration demand torque is greater than or equal to the predetermined reference torque, it may be determined that the driver's willingness to brake in a full-brake situation is strong. Therefore, when the determined deceleration demand torque is greater than or equal to the predetermined reference torque, the controller 120 may switch to a control release state, reflecting the driver's willingness to brake, to prevent the deceleration-related control from being performed in the low-speed driving situation of the vehicle. In this case, in order to inform the driver or the passenger of the deceleration state, the controller 120 may output information about the switching to the control release state.

When the determined deceleration demand torque is less than the predetermined reference torque, the controller 120 may cause the vehicle to decelerate through a higher proportion of regenerative braking compared to hydraulic braking. This will be described with reference to FIG. 3.

FIG. 3 is a graph illustrating a deceleration situation of a vehicle due to operation of a vehicle control device according to an embodiment of the present disclosure.

Referring to FIG. 3, the vehicle may have a preconfigured braking vehicle speed profile for controlling the deceleration of the vehicle in a low-speed driving situation. The braking vehicle speed profile may be configured to reduce motion sickness of a driver or a passenger when the vehicle decelerates in the low-speed driving situation, and may be configured in the form of a dashed line graph representing changes in vehicle speed over time and shown in FIG. 3.

The controller 120 may load or determine the preconfigured braking vehicle speed profile and control the vehicle to decelerate through a braking distribution ratio having a large regenerative braking amount compared to a hydraulic braking amount so as to follow the braking vehicle speed profile. For example, the vehicle may be controlled to decelerate through hydraulic braking and regenerative braking. Therefore, the controller 120 may control the vehicle to decelerate by adjusting the hydraulic braking amount and the regenerative braking amount based on the braking distribution ratio so as to follow the braking vehicle speed profile. In the present disclosure, it is assumed that regenerative braking will be more involved than hydraulic braking in the deceleration of the vehicle by reducing the hydraulic braking amount and increasing the regenerative braking amount. Therefore, when the vehicle decelerated, the controller 120 may control the vehicle to decelerate through hydraulic braking and regenerative braking such that the regenerative braking amount is greater than the hydraulic braking amount, as shown in the graph of FIG. 3, while following the braking vehicle speed profile. However, it should be understood that the regenerative braking amount graph and the hydraulic braking amount graph, shown in FIG. 3, do not have the same physical quantities as the braking vehicle speed profile, but represent only graphical shapes to facilitate the description of changes in the deceleration situation of a vehicle following the braking vehicle speed profile.

When the vehicle decelerates in the low-speed driving situation, the controller 120 may control the vehicle to decelerate while following the braking vehicle speed profile through a high proportion of regenerative braking compared to hydraulic braking, taking into account preconfigured one of multiple regenerative braking detailed setting modes. This will be explained with reference to FIG. 4.

FIG. 4 is a graph illustrating a regenerative braking detailed setting mode that is configured when a vehicle according to an embodiment of the present disclosure decelerates.

Referring to FIG. 4, multiple regenerative braking detailed setting modes according to an embodiment of the present disclosure may be configured to have different amounts of regenerative braking reduction depending on a vehicle's speed. For example, the multiple regenerative braking detailed setting modes may be configured in multiple stages with different amounts of regenerative braking reduction.

Conventionally, as shown in the dashed line graph, a regenerative braking torque profile is configured such that torque for regenerative braking decreases as the vehicle speed decreases and below a certain vehicle speed, the torque increases for creep driving of the vehicle. However, an aspect of the present disclosure is to cause the vehicle to stop rather to creep when the vehicle decelerates in the low-speed driving situation, and thus the multiple regenerative braking detailed setting modes may each be configured to decrease the regenerative braking torque as the vehicle speed decreases, ensuring that the regenerative braking torque reaches 0 Nm when the vehicle speed reaches 0 km/h.

With the multiple regenerative braking detailed setting modes configured, the driver may configure one of the multiple regenerative braking detailed setting modes by manipulating a predetermined manipulation device, such as steering or a paddle shift disposed on a steering column. In addition, the driver and the passenger, may configure one of the multiple regenerative braking detailed setting modes by using a display device provided in the vehicle.