Electronic brake system and operation method thereof

An operation method of an electronic brake system including a plurality of actuators provided in a plurality of wheels, respectively and providing power for braking, and a hydraulic braking device providing braking force by a hydraulic pressure to at least one wheel cylinder of the plurality of wheels when the actuator is inoperable, wherein when the electronic brake system is in a normal operation mode,

• a simulator valve is opened, which controls a flow of a pressing medium in a reservoir path connecting a reservoir storing the pressing medium and a master chamber provided in a master cylinder, and
• a cut valve is closed, which controls the flow of the pressing medium in a connection path connecting the master chamber and the wheel cylinder,
• the actuator brakes a wheel by receiving an electrical signal of a pedal displacement sensor sensing a braking intension of a driver, and
• a pedal simulator disposed inside the master chamber provides a pedal feeling to the driver through an elastic restoration force generated during compression.