| 摘要 |
PURPOSE:To improve accuracy in constant current region and to prevent saturation in accelerating/decelerating current region without requiring improvement of the accuracy of an A/D converter by subjecting the detected analog current value of a servo motor to a non-linear transformation, then subjecting the A/D converted digital value to the inverse transformation. CONSTITUTION:Current detection system for servo motor comprises a means 1 for operating a command value based on a current command signal Ie and an inversely transformed signal Id to produce an operational signal If, a servo amplifier 2 for amplifying the operational signal If and feeding drive current Ig for a servo motor 4, a detector 3 for detecting the value of the drive current Ig and producing a detection signal Ia, a means 6 for subjecting the detected signal Ia to a non-linear transformation and producing a non-linear signal Ib, an A/D converter 5 for subjecting the non-linear signal Ib to A/D conversion and producing a digital signal Ic, and a means 7 for subjecting the digital signal Ic to the inverse transformation and feeding the inversely transformed signal Id toward the operating means 1. The non-linear inversion means 6 exhibits sharp inclination for a micro input and exhibits slow inclination for a large input. |
