| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem of a conventional method that the misjudgment of rotational abnormality occurs because there is such a case that the actual number of revolutions does not amount to a specified number of revolutions or over until a specified time passes when the objective number of revolutions at start of a motor is very small, in the case of judging it to be rotational abnormality if the actual number of revolutions does not reach a specified number of revolutions or over after passage of a specified time. <P>SOLUTION: By setting the rise change rate of motor directive voltage to a value where the fan motor directive voltage becomes maximum until the time when it starts judgment of rotational abnormality at start of the motor, this method can surely prevent the misjudgment of rotational abnormality since the actual number of revolutions of the motor amounts to a specified comparative number of revolutions or over until start of judgment of rotational abnormality even in case that the objective number of revolutions is very small if it is normal. <P>COPYRIGHT: (C)2004,JPO |
