| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electric power steering device capable of more certainly suppressing reduction of a voltage when a power source voltage is reduced, and capable of preferably maintaining an assistable area. <P>SOLUTION: A micro-computer voltage-rising-controls a value of power applied to a motor so as to restrict it to a smaller value than that at a usual time when it is determined that the value of the power source voltage is reduced to a specific threshold value or less. According to this constitution, when it is determined that the voltage of the battery is reduced even when steering assistance is executed at the approximately maximum value of the motor characteristic, the power of the motor is restricted to a smaller value than that at a usual time through voltage-rising control of a voltage-rising circuit. Therefore, further reduction of the voltage of the battery is more certainly suppressed. Further, steering assistance can be continuously executed regarding the steering assistance area not requiring large power. <P>COPYRIGHT: (C)2011,JPO&INPIT |
