Patent ID: 7960940
Filing Date: 2011-06-14
Classification: H02P

Abstract:
1. A motor control device for controlling a d-axis current and a q-axis current on dq coordinates to control a motor, comprising: a q-axis current command value setting unit which sets a q-axis current command value; an upper limit/lower limit setting unit which sets an upper limit and a lower limit of the q-axis current; a comparing unit which compares the q-axis current command value set by the q-axis current command value setting unit and the upper limit and the lower limit set by the upper limit/lower limit setting unit; a q-axis current command value limiting unit which puts a limit on the q-axis current command value in accordance with a comparison result by the comparing unit; and a d-axis current command value setting unit which sets a d-axis current command value, on the basis of the q-axis current command value which is limited by the q-axis current command value limiting unit, wherein the upper limit/lower limit setting unit sets the upper limit and the lower limit in accordance with a rotational angular velocity of the motor, wherein the upper limit/lower limit setting unit determines the upper limit so as to satisfy the following Expression (A), and determines the lower limit so as to satisfy the following Expression (B); wherein: i i R is a stator winding resistance of the motor, φ is a magnetic flux on dq coordinates calculated from the interlinking magnetic flux of a stator caused by a field, ω is the rotational angular velocity at an electric angle of the motor, L L V