A brake control system of a vehicle, comprising:
- a plurality of wheel cylinders including a first wheel cylinder for applying braking force to a first wheel and a second wheel cylinder for applying braking force to a second wheel;
- a power hydraulic pressure source able to generate, by a supply of power, a high hydraulic pressure independent of a brake operation by a driver;
- a manual hydraulic pressure source that includes a master cylinder which pressurizes operating fluid in accordance with a brake operation amount and a regulator which regulates the hydraulic pressure of the power hydraulic pressure source in accordance with a hydraulic pressure of the master cylinder;
- a first system including a first control valve disposed between the power hydraulic pressure source and the plurality of wheel cylinders and a second control valve disposed upstream of the plurality of wheel cylinders between a reservoir return line and the plurality of wheel cylinders, such that the first system connects the power hydraulic pressure source with both the first and second wheel cylinders, regulates the hydraulic pressure of operating fluid from the power hydraulic pressure source, and applies a common hydraulic pressure to both the first and second wheel cylinders;
- a separator valve that cuts off a supply of operating fluid to the second wheel cylinder via the first system when the separator valve is closed;
- a second system which connects the regulator to the second wheel cylinder such that operating fluid can be supplied from the power hydraulic pressure source via the regulator to the second wheel cylinder regardless of whether the separator valve is open or closed;
- a control portion that switches a brake mode from a first brake mode in which the common hydraulic pressure is applied to both the first and second wheel cylinders by the first system to a second brake mode in which the separator valve is closed so that the hydraulic pressure is applied to the first wheel cylinder by the first system and the hydraulic pressure that is regulated by the regulator is applied to the second wheel cylinder by the second system;
- and
- a regenerative brake unit that applies braking force to the first wheel by regenerative control of a motor, wherein
- the first control valve is disposed in a first flow line in which the fluid flows to the plurality of wheel cylinders,
- the second control valve is downstream of the first control valve and disposed in a second flow line that branches from the first flow line and that is connected to the reservoir return line, and
- the control portion increases the hydraulic pressure applied to the second wheel cylinder via the second system more than the hydraulic pressure applied to the first wheel cylinder via the first system by switching the brake mode from the first brake mode to the second brake mode when the braking force applied to the first wheel is a combination of regenerative braking force and hydraulic pressure braking force and a predetermined condition is satisfied.