| 摘要 |
PROBLEM TO BE SOLVED: To provide a servo-drive system for positioning which covers a wide current operating range.SOLUTION: A servo-drive system 20 for feedback-based control of motion and positioning of a motor 33 comprises a current measurement device configured to obtain a measure of current being drawn by the motor 33, therefrom to provide feedback, the current having an operating range, the operating range comprising a relatively large current range for acceleration but remaining within a relatively small current range for steady state operating of the motor. The current measurement device has a first "coarse" sensor 36 optimized for measuring the relatively large current range and a second "fine" sensor 38 optimized for measuring the relatively small current range, thereby to maximize accuracy for feedback during the steady state operation.SELECTED DRAWING: Figure 1 |
