| 摘要 |
PROBLEM TO BE SOLVED: To reduce vibrations of a motor and electromagnetic sound by using one current detecting resistor, and to prevent a plurality of phase currents from changing suddenly. SOLUTION: This motor drive equipment is provided with a plurality of output circuits having upper and lower arm side switching elements which are connected in series. The equipment comprises the current detecting resistor which is connected in series and in common with the plurality of output circuits, a current conduction phase switching circuit which makes electrical continuity of one side switching element in one of the output circuits for a period to correspond to the prescribed electrical angle, and makes the other side switching elements in the other plurality of output circuits perform switching operation, and a current conduction period control part for forming a signal to control the switching operation in such a manner that a first period and a second period exist in each of a plurality of periods in which the period is divided. In the first period, a plurality of the switching elements are set to be electrically continuous. In the second period, one from among the switching elements which are made electrically continuous successively in the first period, is made to be electrically continuous. |
