A machine learning apparatus learns conditions associated with power failure on the side of an AC power supply in a motor control apparatus which converts AC power into DC power, outputs the DC power to a DC link, further converts the DC power into AC power for driving a motor, and supplies the AC power to the motor, includes a state observation unit which observes a state variable including at least one of data associated with the value of a power supply voltage on the AC power supply side, data associated with the amount of energy stored in a DC link capacitor provided in the DC link, and data indicating whether a protective operation for the motor control apparatus is successful, and a learning unit which learns conditions associated with power failure on the AC power supply side in accordance with a training data set defined by the state variable.