CONTROL DEVICE AND POWER CONTROL SYSTEM

A control device (10) for controlling a power source (20) connected to an alternating-current (AC) power system includes: a frequency control unit (201) that controls a frequency of the power source operating in a constant-voltage constant-frequency control scheme; a power calculation unit (203) that calculates, when the frequency control unit varies a frequency of the power source, a variation of an effective power output from the power source; an arithmetic unit (205) that calculates a frequency characteristics constant of the AC power system, based on a variation of the frequency of the power source and the variation of the effective power output from the power source; and a selection unit (207) that selects a control scheme for the power source, based on the frequency characteristics constant of the AC power system.