| 摘要 |
PURPOSE:To shorten the time required for starting a sensorless and brushless motor, by performing a high-speed starting operation in a first starting time, and by performing a low-speed starting operation when the motor fails to start by the high-speed starting operation. CONSTITUTION:In the case starting a motor 11, a drive control part 27 for the motor 11 performs a first drive operation wherein the excitations of armature coils 11u, 11v, 11w of the motor 11 are switched at a predetermined high- speed period and by the use of a predetermined starting pattern. When a start- completion determining part 28 determines that the starting of the motor 11 is completed by the first drive operation, the part 27 performs in a shifting way a predetermined ordinary drive operation. When the start-completion determining means 28 does not determine that the starting of the motor 11 is completed by the first drive operation, the excitations of the armature coils 11u, 11v, 11w are switched at a predetermined low-speed period and by the use of a predetermined starting pattern. Therefore, when the load of the motor 11 in its starting time is small, its starting time is shortened, and when the load of the motor 11 in its starting time is large, the motor can be started adequately by its second starting. |
