Control device, control system, control method, recording medium and machine learning device

A control device that controls a target vacuum pump including a motor, including: a decision unit that decides, using at least one of target state quantities at a time of a past stop process of the target vacuum pump or another vacuum pump wherein the target state quantities are state quantities which fluctuate in accordance with a load at a time of a process of stopping a vacuum pump, a normal fluctuation range or a normal time fluctuation behavior of the target state quantity at the time of the stop process; and a control unit that controls the motor, wherein the control unit compares the target state quantity at the time of the process of stopping the target vacuum pump with the normal fluctuation range or the normal time fluctuation behavior, and changes a method of controlling the motor during the stop process depending on the comparison result.