| 摘要 |
PURPOSE: To improve the dynamic behavior of a stepper motor which operates at a characteristic angular velocity by determining a maximum constant current value, establishing a sequence of a current value pair, and supplying a current to a coil in duration of fine steps based upon a desired angular velocity. CONSTITUTION: The square root I of a secondary sum I<2> =I<2> xi +I<2> yi of M current value pairs (Ixi , Iyi ) is substantially equal to a maximum constant current value I0 . Further, plural Ixi is are substantially equal to ICOS (360 deg. i/N+α). At least one current value Ixi has a different value from it. Here, (i) is an index in a sequence of 1 to M, N is a divisor of M, andαis an arbitrary constant. For example, a stepper motor 52 is driven by being supplied with four current vector control signals Xi , Yi , Sxi , and Syi per fine step (i) through a stepping motor driver 53 at a constant frequency, relating directly to the desired angular velocity. The control signals Xi and Yi are linearly proportional to current Ix and Iy , and the control signals Sxi and Syi specify the senses and signs of the currents IX and IY. |
