| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a motor control unit capable of estimating a current flowing into a switching device based on the value of current flowing into a battery, and performing excessive current prevention control, based on an estimated value. <P>SOLUTION: This motor control unit (1) controls a current flowing into a brushless motor (M) from the battery (BT) by means of PWM control, based on the duty ratio. This unit includes current detecting devices (7, 11) that detect the battery current value; an estimation method determining device (19) that selects the first estimating method, when the battery current value is larger than a predetermined first determination value; and the duty ratio is larger than a predetermined second determination value, and selects the second estimating method in the other cases, and an estimation motor current value calculating device (20) that calculates the estimated motor current value, based on the battery current value and the duty ratio, when the first estimating method is selected, and uses the battery current value as the estimation motor current value when the second estimating method is selected. <P>COPYRIGHT: (C)2009,JPO&INPIT |
