Power control device, fixing device, and image forming apparatus

A power control device comprising:

• a heater configured to generate heat by being supplied with an AC voltage;
• a zero-cross detecting unit configured to detect a zero-cross point of the AC voltage;
• a triac configured to switch a conduction state in which the AC voltage is supplied to the heater and a non-conduction in which supply of the AC voltage to the heater is cut off;
• a supplying unit configured to supply a current to the triac;
• and
• a controlling unit configured to control a state of the triac by outputting a control signal,
• wherein the controlling unit controls the state of the triac by outputting the control signal in a control period in which a plurality of half-waves of the AC voltage with a first polarity and a plurality of half-waves of the AC voltage with a second polarity different from the first polarity constitute one period of control,
• wherein an electric charge of the supplying unit is discharged when the control signal is outputted in the half-wave of each of the first polarity and the second polarity and is charged when the control signal is not outputted in the half-wave of the first polarity, and
• wherein in a case that a single zero-cross point is detected by the zero-cross detecting unit in a first half-wave, a single control signal is outputted in a second half-wave after the first half-wave, and
• wherein in a case that a plurality of zero-cross points are detected by the zero-cross detecting unit in the first half-wave, a plurality of control signals are outputted in the second half-wave.