MACHINE POSITION CONTROL DEVICE

摘要

Even in case the rigidity of a drive system of a load by an electric motor is low, the position of the load can be highly precisely controlled, by making it possible that the position control of the load by feeding back the load position signal is made in the same stability as that of a semi-close control by feeding back only the position signal of the electric motor. For this, a compensation for a phase delay is made by a stabilization compensating circuit (80) upon a load position signal (x<SUB>l</SUB>) or the measured value of the current position of the load (20). In a position signal synthesizing circuit (90), a harmonic wave portion is then replaced from an electronic motor position signal (x<SUB>m</SUB>) or the measured value or the current position of the electric motor (30) into a control object position signal (x<SUB>fb</SUB>), and this control object position signal (x<SUB>fb</SUB>) is fed back to a position control circuit (110) thereby to output a torque command signal indicating a torque target value for the electric motor (30) to drive the load (20).