Power factor correction apparatus and power supply apparatus

A power factor correction apparatus, comprising:

• a power factor correction unit switching input power and controlling a phase difference between a voltage and a current of the input power to correct a power factor thereof;
• and
• a control unit providing a switching control signal having a preset number of pulses for a predetermined time to the power supply unit to control power switching of the power factor correction unit, and when a voltage level of output power of the power factor correction unit is equal to or higher than that of at least one intermediate voltage set between a preset normal operating voltage and a preset abnormal operating voltage, skipping a portion of the number of pulses of the switching control signal for the predetermined time.