| 摘要 |
PURPOSE:To protect the components of controller against breakdown by preventing a brushless motor from being locked. CONSTITUTION:A DC power supply Vcc is switched at an inverter section 2 and applied to the armature windings U, V, W of a brushless motor 1 while transistors Ua, Va, Ha, Xa, Ya and Za at the inverter section 2 are driven based on a position detection signal of the brushless motor 1 detected at a position detecting section 3 in order to control the rotation of the brushless motor. In such controller and control method for brushless motor, voltage of a power supply (DC power supply Vcc) is detected at a power supply voltage detecting section 5. A control circuit 6 compares a voltage detection signal with a predetermined value and when the detected voltage is lower than the predetermined value, switching is made for the brushless motor from position detecting operation to synchronous operation. |
