| 摘要 |
PROBLEM TO BE SOLVED: To accurately detect the eccentric quantity of drum. SOLUTION: A control angle α for the speed control of motor is determined by adding an absolute speed component depending on the difference between real rotating speed and target rotating speed and a relative speed component depending on the fluctuation amount of real rotating speed. First of all, the contribution ratio of relative speed component is set smaller and phase control is performed so as to rotate the drum at 130 rpm (S14). At such a time, the eccentric quantity is found from the fluctuation amplitude of motor current (S15). When the ecccentric quantity exceeds a prescribed value, the contribution ratio of relative speed component is reset relatively larger (S17) and the eccentric quantity is detected again (S18). Thus, even when the influences of friction between the main shaft of drum and a bearing are reduced within the range of large eccentric quantity and the rotational fluctuation of drum is relatively enlarged, the rotating speed can easily follow up this fluctuation, the fluctuation of motor current obviously appears in the eccentric quantity, and the detection accuracy of eccentric quantity is improved. |
