| 摘要 |
<P>PROBLEM TO BE SOLVED: To enhance responsiveness when generating braking force, without enlarging an electric motor for driving a motor-driven braking force generating means. <P>SOLUTION: A target brake liquid pressure calculating means M1 calculates target brake liquid pressure to be generated in a slave cylinder. A differential means M2 calculates a rate of change in the target brake liquid pressure by differentiating the target brake liquid pressure in time. A field current calculating means M3 calculates a field current command value of the electric motor for driving the slave cylinder based on the rate of change in the target brake liquid pressure. An electric motor control means M4 controls a field by weakening the electric motor based on the field current command value. When the rate of change in the target brake liquid pressure is large, it is an emergency when requiring to suddenly rise the braking force, and at this time, a field quantity is increased by weakening the electric motor by increasing the field current command value, and the responsiveness can be enhanced when generating the braking force by quickly operating the slave cylinder by increasing a rotating speed of the electric motor. <P>COPYRIGHT: (C)2008,JPO&INPIT |
