Control method and control apparatus for PFC circuit and switching power supply system

A control apparatus for a power factor correction (PFC) circuit, the control apparatus comprising:

• at least one processor configured to:
• obtain a sampled voltage data set, the sampled voltage data set representing a sampled voltage for sampling an output voltage of the PFC circuit at a predetermined sampling frequency within a target time window of a predetermined duration;
• determine a sampled average value of a sampled voltage within a time window based on the sampled voltage data set;
• determine a difference between the sampled average value and a reference output voltage;
• and
• generate a control signal to control ON and OFF of a switching device of the PFC circuit, wherein the at least one processor, to generate the control signal, is configured to:
• obtain a signal indicative of a phase of an input voltage of the PFC circuit and an input current of the PFC circuit;
• determine an effective value of the input voltage;
• and
• generate the control signal by comparing the input current with a signal obtained by dividing, by the effective value, a product of the difference and the signal indicative of the phase of the input voltage of the PFC circuit.

A non-transitory computer-readable medium embodying programmed instructions which, when executed by at least one processor, cause the at least one processor to:

• obtain a sampled voltage data set, the sampled voltage data set representing a sampled voltage for sampling an output voltage of a power factor correction (PFC) circuit at a predetermined sampling frequency within a target time window of a predetermined duration;
• determine a sampled average value of a sampled voltage within a time window based on the sampled voltage data set;
• determine a difference between the sampled average value and a reference output voltage;
• and
• generate a control signal to control ON and OFF of a switching device of the PFC circuit, wherein the programmed instructions, to generate the control signal, cause the at least one processor to:
• obtain a signal indicative of a phase of an input voltage of the PFC circuit and an input current of the PFC circuit;
• determine an effective value of the input voltage;
• and
• generate the control signal by comparing the input current with a signal obtained by dividing, by the effective value, a product of the difference and the signal indicative of the phase of the input voltage of the PFC circuit.