Matsushita Electric Industrial Co., Ltd.

Hirofumi Sakai

Tomoharu Yokouchi

Yasunori Yamamoto

Taishi Iwanaga

Masashi Inao

Ken Maruyama

The motor driver having a plurality of output circuits each having two switching elements connected in series includes: a phase switch circuit for putting a switching element on one side of one output circuit among the plurality of output circuits in the ON state during a time period corresponding to a predetermined electrical angle, and performing switching operation for switching elements on the other side of plural output circuits among the remaining output circuits; and a conduction period control section. The conduction period control section generates a signal for controlling the switching operation. Specifically, when the number of times of switching operation performed during the time period corresponding to the predetermined electrical angle is equal to or less than a predetermined value, a switching element corresponding to a phase, for which the magnitude of the current should be decreased, is turned OFF in the time period corresponding to the next predetermined electrical angle.

PWM controlled motor drive

A motor drive method for a motor driver having output circuits each including upper and lower side switching elements connected in series, and a current detection resistance connected in series with the output circuits in common. The motor drive method includes the steps of: turning ON a switching element on one side of one of the output circuits for a time period corresponding to a predetermined electrical angle; and repeatedly switching switching elements on the other side of a plurality of output circuits among the remaining ones of the output circuits. In the switching step, each of a plurality of periods obtained by dividing the time period corresponding to the predetermined electrical angle includes a first period in which one of the switching elements to be switched is turned ON and a second period in which another one of the switching elements is turned ON.

Motor drive method and motor driver

A motor driver having output circuits each including upper and lower side switching elements connected in series. The motor driver includes: a current detection resistance connected in series with the output circuits in common; a phase switch circuit for turning ON a switching element on one side of one of the output circuits for a time period corresponding to a predetermined electrical angle and switching switching elements on the other side of a plurality of output circuits among the remaining ones of the output circuits; and an ON-period control section for generating a signal for controlling the switching operation so that each of periods obtained by dividing the time period includes a first period in which a plurality of switching elements are turned ON and a second period in which one of the switching elements turned ON in the first period is kept ON.

Growing community of inventors

Kyoto, Japan

Hirofumi Sakai