Experimental evaluation of mechanical and electrical power consumption of feed drive systems driven by a ball-screw

Abstract An experimental analysis of the mechanical and electrical power consumption of feed drive systems is presented in this paper. The main components affecting the power consumption are the motor, bearings, ball-screw, and table. The power consumption of the motor has been investigated experimentally through the study of the electrical efficiency. The efficiency has been calculated from the acquired angular velocity and supplied torque for several velocities and loads. The study shows how the working conditions of the motor heavily influence the efficiency of the motor and therefore the power consumption of the whole feed drive system. Moreover, the mechanical power consumption of each component of the feed drive has been investigated, showing that the main component responsible for the consumption is the ball-screw. Thus, in order to clarify the influence of the constructive parameters of the ball-screw on the power consumption, four kinds of ball-screws differing in the lead dimension and the preload condition have been considered. Furthermore, it clarifies the relation between the power consumption of the feed drive system and the working velocity of the table. Finally, the advantages and disadvantages of each feed drive mechanical configuration are discussed, emphasizing that the driven factor that affects the power consumption the most is the angular velocity, due to the trade-off between the motor efficiency and the mechanical power loss from the friction of the components in relative motion. This research can help the selection of the lead of the ball-screw, from an energetic point of view, in order to get higher efficiency of the feed drive.