| 摘要 |
PROBLEM TO BE SOLVED: To suppress noise and vibration of a fan motor and further reduce its power consumption. SOLUTION: The method and apparatus for controlling the fan motor involve a number of revolutions calculating portion 5 that calculates an actual number of revolutions Rm based on the period of a position signall outputted from a position sensor 4 built in the brushless DC motor 3 for rotating a fan 3c, a number of revolutions controlling and computing portion 6 that uses an externally given number of revolutions command Rm* and the actual number of revolutions Rm as inputs to calculate the difference between them and outputs a pulse width command value Vd corresponding to the difference, a voltage phase lead angle setting portion 7 that outputs a voltage phase lead angle Pa, a rotor electrical angle calculating portion 8 that uses the position signal as an input to calculate a rotor electrical angle Pe, a motor voltage phase determining portion 9 that uses a voltage phase lead angle Pa and a rotor electrical angle Pe as inputs and outputs a motor voltage phase Px, and a voltage vector computing portion 10 that uses the pulse width command value Vd and the motor voltage phase Px as inputs and outputs drive signals Gu, Gv, Gw, Gx, Gy, and Gz. |
