CONTROL APPARATUS OF ALTERNATING-CURRENT MOTOR IN WHICH INSTRUCTION CURRENT VALUE IS LIMITED BY ACTUAL DRIVE CURRENT VALUE

摘要

A control apparatus of an alternating-current motor is provided. The apparatus provides a final magnetic flux-axis (D-axis) instruction voltage value (Vds^r*) and a final rotational force-axis (Q-axis) instruction voltage value (Vqs^r* ) to an inverter for driving a motor, in accoradance with a magnetic flux-axis (D-axis) instruction current value (ids^r^*) and a rotational force-axis (Q-axis) instruction current value (iqs^r*). Herein, values of actual drive current flowing in each phase of the alternating-current motor are measured, a magnetic flux-axis (D-axis) drive current value (Ides) and a rotational force-axis (Q-axis) drive current value (Iqse) of the alternating-current motor are calculated from the measured actual drive current values, and the rotational force-axis (Q-axis) instruction current value (iqsr*) is changed to be a value proportional to the a difference between a set maximum-current value (Imax) and the magnetic flux-axis (D-axis) drive current value (Idse) when an average value between the magnetic flux-axis (D-axis) drive current value (Idse) and the rotational force-axis (Q-axis) drive current value of the alternating-current motor exceeds the set maximum-current value.;COPYRIGHT KIPO 2016