Electric booster brake apparatus and controlling method thereof

An electric booster brake apparatus, comprising:

• an electric booster unit comprising a motor, a motor piston, and a master cylinder and configured to adjust a displacement of the motor piston in a linear movement in response to a rotation of the motor to pressurize the master cylinder containing a brake fluid;
• an electronic stability control (ESC) operating unit configured to calculate a braking pressure required for braking of a vehicle, and comprising a pressure sensor configured to measure a pressure in the master cylinder;
• and
• an electric-booster control unit configured to receive a first value and a second value from the ESC operating unit, the first value being indicative of the required braking pressure and the second value being indicative of the pressure in the master cylinder, the electric-booster control unit being configured to control a position of the motor piston based on a motor piston displacement and a compensation displacement which are derived from the first value and the second value,
• wherein the electric-booster control unit comprises:
• a feedforward control unit configured to convert the first value into the motor piston displacement;
• and
• a feedback control unit configured to calculate the compensation displacement of the motor piston based on a difference between the first and second values.