An image-forming apparatus includes: a fixing unit; a load; a power source circuit section; a fixation electrical current detecting body; a total electrical current detecting body; a storage unit; and a fixation control unit. The fixing unit fixes a toner image using a heat generator. The power source circuit section supplies electric power to the load. The storage unit stores electrical current change amount data establishing an amount of change in the magnitude of the total electrical current relative to an amount of change in a phase for each value of the power factor of the fixing unit. The fixation control unit finds the power factor of the fixing unit, and alters the phase at which the heat generator starts to be energized on the basis of the power factor thus found and the electrical current change amount data, so that the total electrical current value approaches a target value.