| 摘要 |
PURPOSE:To reduce a torque ripple and a current ripple by forming in phase a counterelectromotive force waveform induced in a drive coil and a drive current waveform flowed to the drive coil. CONSTITUTION:A rotor magnet 21 is composed of main and subpoles 22, 23. A revolving magnetic field generated at 3-phase drive coils 34-26 disposed at an equal interval around the poles 22 act on the poles 22 to rotatably energize the magnet 21. Hall elements 27-29 are disposed at an interval of 2/3 of electric angle at the prescribed gap near the pole 23, the outputs are amplified by drive amplifiers 33-35 via square calculators 30-32 and flowed to drive coils 24-26. The waveforms of the counterelectromotive force induced in the coils 24-26 become the same as those of the drive currents flowed to the coils 24- 26. |
