Motor control device and machine tool system for controlling motor in accordance with amount of drop in power supply voltage

A motor control device for controlling a plurality of motors which respectively drive different axes, the motor control device comprising:

• a rectifier configured to convert AC power input from an AC power supply into DC power and output the DC power to a DC link;
• an inverter configured to convert the DC power of the DC link into AC power to be supplied as drive power for each of the motors and outputs the AC power;
• an AC voltage detection unit configured to detect an AC voltage value on an AC input side of the rectifier;
• a state determination unit configured to determine that a voltage dropped state has been set when the AC voltage value is smaller than a certain specified voltage and that a normal state has been set when the AC voltage value is not less than the specified, voltage;
• and
• an output control unit configured to control each of the motors in accordance with an amount of voltage drop with respect to the specified voltage of the AC voltage value when the state determination unit determines that the voltage dropped state has been set.