In a control apparatus, a magnetic flux information acquiring unit acquires magnetic flux information of magnetic poles of a rotating electric machine. A fundamental setting unit sets a fundamental command value for supplying a fundamental current to a winding of the rotating electric machine. A harmonic setting unit sets, based on the magnetic flux information acquired by the magnetic flux information acquiring unit, a harmonic command value for supplying a reduction current to the winding. The reduction current is a harmonic current for reducing variation in a radial electromagnetic force acting on a rotor of the rotating electric machine. An operating unit operates, based on the fundamental command value set by the fundamental setting unit and the harmonic command value set by the harmonic setting unit, an electric power converter to supply the winding with a drive current that is obtained by superimposing the reduction current on the fundamental current.