Motor control apparatus

A motor control apparatus that divides an electric current flowing into and out of a motor driven by an inverter into a torque current and an excitation current and individually controls the torque current and the excitation current on the basis of a torque current command obtained from a torque command and an excitation current command, the motor control apparatus comprising:

• a secondary-magnetic-flux-command calculating unit including a first calculating unit that calculates a minimum current secondary magnetic flux command from the torque command under a condition that a current root-mean-square value due to the torque current command and the excitation current command are minimized, the secondary-magnetic-flux-command calculating unit calculating, on the basis of an inverter frequency and the minimum current secondary magnetic flux command, a secondary magnetic flux command with which a total loss of a copper loss and an iron loss of the motor decreases to be smaller than the total loss that occurs when the minimum current secondary magnetic flux command is used;
• and
• a PWM-signal generating unit that generates the torque current command and the excitation current command from the torque command and the secondary magnetic flux command, performs vector control such that a detection value of the torque current and a detection value of the excitation current respectively coincide with the torque current command and the excitation current command, and generates a control signal for turning on and off a switching element included in the inverter.