| 摘要 |
Regarding a brushless motor control device and a control method, the phase voltage Vsu of any one phase of the three-phase brushless motor is detected by a sub-coil (Su) (6). A time interval between adjacent zero-cross points a1 and a2 thereof is measured. Based on the time interval between the zero-cross points, a time T/3 and a time 2T/3 are calculated. Then, based on the time t/3 and the time 2T/3, phases of zero-cross points b1 and c1 of the two other phases are estimated. Then, based on the estimated zero-cross points b1 and c1, phases of the phase voltages of the two other phases are estimated, thereby controlling conduction on each phase coil of the three-phase brushless motor. |
