A novel V/f control of induction motors for wide and precise speed operation

Abstract

The V/f control method is one of speed control methods for induction motors. We have proposed an auto-boost voltage method to compensate the voltage drop of stator impedance and a slip frequency compensation method to decrease the speed error caused by the change of load. Stability of the proposed V/f control system is analyzed by root locus. Steady-state torque-speed characteristics and transient responses of proposed system are presented by experimental system. Compared with the constant V/f control method, speed accuracy of proposed method is improved in various speeds and loads.