Motor control device

A motor control device configured to derive a first voltage command value serving as a command value of a voltage of a component in a first axis and a second voltage command value serving as a command value of a voltage of a component in a second axis orthogonal to the first axis in a vector control rotation coordinate, and drive a motor serving as a synchronous motor on the basis of the first voltage command value and the second voltage command value, the motor control device comprising:

• a current command value deriving unit configured to derive, as a first current command value, a current of the component in the first axis corresponding to a torque command value serving as a command value of a torque of the motor, and derive, as a second current command value, a current of the component in the second axis corresponding to the torque command value on the basis of a torque current map indicating a relationship between the torque of the motor and the current of the component in the first axis and the current of the component in the second axis;
• and
• a voltage command value deriving unit configured to perform a first process of deriving the first voltage command value on the basis of the first current command value and deriving the second voltage command value on the basis of the second current command value, and a second process of deriving the first voltage command value on the basis of the second current command value and deriving the second voltage command value on the basis of a limit voltage of the motor control device and the first voltage command value, wherein
• the voltage command value deriving unit switches a process of deriving the voltage command value from the second process to the first process when it is determined that the voltage command value satisfying the torque command value is derivable by the first process in a case in which the motor is driven on the basis of the voltage command value derived by the second process.