A power source apparatus includes a first converter having a reactor L1, a switching element Q1, and a rectifier D1; a second converter connected in parallel with the first converter and having a reactor L2, a switching element Q2, and a rectifier D2; a capacitor C1 connected to output ends of the first and second converters; a current detector R1 detecting a resultant current of currents of the first and second converters; a controller 13 driving the switching element Q1 and the switching element Q2; and a selector. In a case where the resultant current indicates a first reference value, if one of first and second drive signals of the controller is active, the active drive signal is deactivated, and if both the first and second drive signals are active, one of the first and second drive signals that is active longer than the other is deactivated.