JPS6460286A - Method of suppressing torsional vibration of induction motor - Google Patents

Abstract

PURPOSE:To suppress torsional vibration generating to a rotating shaft, by finding a revised torque reference to which calculated vibromotive torque is subtracted from torque reference and by controlling torque current components based on this revised torque reference. CONSTITUTION:A rotor position detected by a position sensor 1 is forwarded to an adder 17 as well as to a two-story differentiator 2, in which angular acceleration is operated. With a multiplier 5 a total inertial moment of an induction motor 40 and a rotating section of a mechanical load 50 is multiplied by this angular acceleration to find inertial torque. The deviation of this inertial torque from the reference torque is operated with a multiplier 12 and this deviation becomes the revised torque reference. This torque reference is then divided with a divider 14 based on the flux reference and the amplitude reference of a controllable current source 18 and a controlled angle of advance is operated with a vector operation circuit 15. Based on this amplitude reference and the phase reference from the adder 17 the amplitude and the phase of the current to the induction motor 40 is controlled.