| 摘要 |
PURPOSE:To obtain a constant torque having no ripple by detecting signals similar to the actual interlinkage magnetic fluxes of drive coils, and flowing the current proportional to the reciprocal of the signal to the coils. CONSTITUTION:A drive current of a motor 1 is controlled by a series control transistor 2. The current of the transistor 2 is detected by an ultrafine resistor R, and the detected voltage is fed back to a current/voltage converter 3. On the other hand, the induced voltage of the drive coil of the motor 1 is detected by an induced voltage detector 4, thereby forming a crossing magnetic flux similar signal of the energizing phase in a crossing magnetic flux simulating circuit 5. This similar signal is applied to a multiplier 6, and multiplied by a drive current detection voltage. The multiplied result is applied to an operational amplifier 7, compared with a torque command voltage, and the output is applied to a voltage/current converter 3. As a result, the current inversely proportional to the interlinkage magnetic flux of the energizing phase and proportional to the torque command voltage is flowed as a motor drive current. |
