| 摘要 |
PROBLEM TO BE SOLVED: To reduce the power loss in the power amplifiers of a motor as feeding to it smoothly its driving currents, by controlling the current applications of its second power amplifying means in response to a waveform shaping signal and the output signals of a synchronous-rectification controlling means. SOLUTION: In the control time-zone of this motor by a synchronous rectification, the second NMOS-type power transistors of second power amplifiers 8, 9, 10 are so turned on as to control to the respondent values to a command signal Ad motor driving currents I1, I2, I3 of the currents fed to its coils. While the second power amplifiers 8, 9, 10 feed to the three-phase coils 2, 3, 4 respectively the positive-polarity currents of the driving currents I1, I2, I3, since the waveforms of these positive-polarity currents become the amplified waveforms of second distribution-current signals G1, G2, G3, the waveforms of the currents I1, I2, I3 become continuously varying smooth waveforms. Also, first and second current feeding signals C1, C2 are varied in accordance with the command signals Ad to reduce the power losses caused by the input currents of the first and second power amplifiers 5-10. As a result, the losses of the power amplifiers 5-10 can be reduced as smoothing the driving currents of the motor. |
