Positional accuracy of CNC drives equipped with an AC induction motor

Abstract

Work has been done in this thesis to evaluate the performance of an induction motor in machine tools. AC servomotors have been the popular choice of feed drives due to its superior servo properties to induction motors based on similar field oriented control schemes. Advantages over the servomotor such as cost etc make the induction motor an attractive alternative which forms the basis of motivation to evaluate use of induction motors in machine tools.Simulations of both motors were done to evaluate the effect of the respective motor parameters on feed drive performance. Experiments were done on commercial machine tools with AC servo feed drives to compare the effects of system parameters on drive performance. Lastly, an induction motor was implemented on a machine tool and its steady state accuracy was evaluated as well as its tracking accuracy compared against that of an AC servomotor on the same machine tool.