CONTROL METHOD AND CONTROL APPARATUS FOR PFC CIRCUIT AND SWITCHING POWER SUPPLY SYSTEM

1 . A method for controlling a power factor correction (PFC) circuit, the method comprising:

obtaining 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;

determining a sampled average value of a sampled voltage within a time window based on the sampled voltage data set;

determining a difference between the sampled average value and a reference output voltage; and

generating a control signal to control ON and OFF of a switching device of the PFC circuit based on a product of the difference and a signal indicative of a phase of an input voltage of the PFC circuit.

2 . The method of claim 1 , wherein determining the sampled average value further comprises:

subtracting at least one sampled voltage within a previous time window from a first summed value of sampled voltage data within a previous time window preceding the target time window to generate an intermediate value, a sampled point corresponding to the at least one sampled voltage being located within the previous time window and outside the target time window;

adding the intermediate value to at least one sampled voltage obtained after the previous time window to generate a second summed value of sampled voltage data within the target time window; and

determining the sampled average value based on the second summed value and a number of samples within the target time window.

3 . The method of claim 2 , wherein sampled voltage data within the previous time window and within the target time window are stored in a first-in-first-out manner.

4 . The method of claim 2 , wherein the number of samples within the target time window is 2 to a power of M, where M is a positive integer.

5 . The method of claim 4 , wherein determining the sampled average value further comprises:

right shifting the second summed value based on the number of samples to generate the sampled average value.

6 . The method of claim 1 , wherein the predetermined duration is a period duration of a voltage across an alternating current (AC) AC side of the PFC circuit.

7 . The method of claim 1 , wherein generating the control signal further comprises:

obtaining the input voltage and an input current of the PFC circuit; and

generating the control signal based on a product of the input voltage and the difference and based on the input current.

8 . 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 based on a product of the difference and a signal indicative of a phase of an input voltage of the PFC circuit.

9 . The control apparatus of claim 8 , wherein the at least one processor, to determine the sampled average value, is further configured to:

subtract at least one sampled voltage within a previous time window from a first summed value of sampled voltage data within a previous time window preceding the target time window to generate an intermediate value, a sampled point corresponding to the at least one sampled voltage being located within the previous time window and outside the target time window;

add the intermediate value to at least one sampled voltage obtained after the previous time window to generate a second summed value of sampled voltage data within the target time window; and

determine the sampled average value based on the second summed value and a number of samples within the target time window.

10 . The control apparatus of claim 9 , wherein sampled voltage data within the previous time window and within the target time window are stored in a first-in-first-out manner.

11 . The control apparatus of claim 9 , wherein the number of samples within the target time window is 2 to a power of M, where M is a positive integer.

12 . The control apparatus of claim 11 , wherein the at least one processor, to determine the sampled average value, is further configured to:

right shift the second summed value based on the number of samples to generate the sampled average value.

13 . The control apparatus of claim 8 , wherein the predetermined duration is a period duration of a voltage across an alternating current (AC) side of the PFC circuit.

14 . The control apparatus of claim 8 , wherein the at least one processor, to generate the control signal, is further configured to:

obtain the input voltage and an input current of the PFC circuit; and

generate the control signal based on a product of the input voltage and the difference and based on the input current.

15 . 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 based on a product of the difference and a signal indicative of a phase of an input voltage of the PFC circuit.

16 . The non-transitory computer-readable medium of claim 15 , wherein the programmed instructions, to determine the sampled average value, further cause the at least one processor to:

subtract at least one sampled voltage within a previous time window from a first summed value of sampled voltage data within a previous time window preceding the target time window to generate an intermediate value, a sampled point corresponding to the at least one sampled voltage being located within the previous time window and outside the target time window;

add the intermediate value to at least one sampled voltage obtained after the previous time window to generate a second summed value of sampled voltage data within the target time window; and

determine the sampled average value based on the second summed value and a number of samples within the target time window.

17 . The non-transitory computer-readable medium of claim 16 , wherein the number of samples within the target time window is 2 to a power of M, where M is a positive integer.

18 . The non-transitory computer-readable medium of claim 17 , wherein the programmed instructions, to determine the sampled average value, further cause the at least one processor to:

right shift the second summed value based on the number of samples to generate the sampled average value.

19 . The non-transitory computer-readable medium of claim 15 , wherein the predetermined duration is a period duration of a voltage across an alternating current (AC) side of the PFC circuit.

20 . The non-transitory computer-readable medium of claim 15 , wherein the programmed instructions, to generate the control signal, further cause the at least one processor to:

obtain the input voltage and an input current of the PFC circuit; and

generate the control signal based on a product of the input voltage and the difference and based on the input current.