| 摘要 |
PURPOSE:To prevent the vibration that occurs when starting a sensorless brushless motor for driving a compressor for air conditioner. CONSTITUTION:A brushless motor includes a permanent magnet rotor and a plurality of armature windings 3, and the energization of the armature windings 3 is controlled by detecting the position of the rotor based on induced voltage generated in the armature windings 3. An external control operating means 5 applies power to the armature windings 3 by external control operation. The rotation speed of the external control operating means 5 is gradually increased in the region from start to a specified rotation speed of the rotor. A current limit setting means 8 for setting current limiting value for energization, is thus fed with the rotation speed of the rotor by the external control operating means 5, and limits overcurrent according to the relation between the torque of load driven by the brushless motor and the rotation speed. |
