| 摘要 |
PROBLEM TO BE SOLVED: To conduct appropriate currents for positioning to a stator coil in accordance with the load of a brushless motor in the case of starting a brushless motor by sensor-less drive.SOLUTION: At first, the start of a brushless motor 10 is tried by first start processing including first positioning processing. In the first positioning processing, a current value to be conducted to the specific phase of a stator coil is set so as to be smaller than that in second positioning processing. Thus, when the brushless motor 10 is in a regular load state, excessive torque is not generated so that a rotor can be appropriately positioned. When the start of the brushless motor 10 by the first start processing fails, second start processing including the second positioning processing is executed. In the second positioning processing, currents having a larger value than that in the first start processing can be conducted. Thus, even when the brushless motor 10 is in a high load state, the possibility of the start of the brushless motor 10 can be increased. |
