Cutting Power Estimation via External Voltage and Current Sensors on Feed-Drive Axis for the Straight Milling Process

Abstract

This study proposes a method to monitor cutting power using external voltage and current sensors installed on the feed-drive motor of a machining center. The tool load is crucial in the machining process, in particular, in metal cutting. Force/torque sensors enable for high-quality cutting force monitoring, but suffer from high investment costs. Therefore, this study uses voltage and current sensors, which are easy to implement and do not interfere with the process. This method calculates the cutting power by estimating the back-electromotive force, which is the induced voltage generated by the flux change in the motor, and filtering the cutting current which contributes only the process. The method is experimentally validated in straight slot-milling tests and compared to a dynamometer.