Speed control of a two-degrees of freedom induction motor with rotor Helical Motion for industrial applications

This paper describes the realization of a two-degrees of freedom induction motor prototype with rotor helical motion, suitable for several industrial applications as grinders, augers, drilling and milling spindles, robotic arms and drives for medical tools and prostheses. This prototype was realized by combining a three-phase tubular linear induction motor (TLIM) with the stator of a three-phase rotary induction motor, resulting in a THMIM (Tubular Helical Motion Induction Motor). Moreover, a possible simple electrical drive, capable to control the helical motion, is proposed, simulated and analyzed. In particular, the mathematical model of the THMIM has been initially developed and, then, the complete drive has been simulated in MATLAB-Simulink. The simulation results demonstrate that, by acting separately on the control of rotary and tubular machine components, a very accurate controlled helical motion can be achieved.