| 摘要 |
PURPOSE: To suppress torque ripple by providing six additional commutation steps between six original steps through the use of an additional Hall effect sensor and current modulation. CONSTITUTION: The motor is provided with a Hall sensor assembly being fixed to a printed circuit board in the form of a stator ring 13 and comprising two sets of three Hall sensors 11 being excited through a single magnet 15 fixed to a motor shaft 17. In each set, the sensors are displaced mechanically by 60 deg.. The second set of three sensors are arranged similarly and displaced mechanically by 15 deg. (electrical angle of 30 deg.) from the first set. Sensors S1, S2 and S3 constitute the first set and sensors S4, S5 and S6 constitute the second set. Sensors in both sets generate signals of identical code wherein the signal from the second set is displaced mechanically by 15 deg. from the first set. Combined signal of the second set is reduced to one effective signal through an exclusive OR process. |
