Adaptive Switching Frequency for PFC Circuit Light Load Efficiency

The patent implements dynamic switching frequency adjustment based on load conditions. At light loads, the switching frequency is reduced to allow resonant current to complete its cycle before the FET turns on, achieving zero current switching. This dynamic adaptation resolves the contradiction by making the switching behavior flexible rather than fixed, reducing THD without significantly complicating the circuit structure.

The patent uses feedback from the resonant current detection to control the timing of FET switching. By monitoring the resonant current waveform and adjusting the switch turn-on timing accordingly, the system achieves zero current switching at light loads. This feedback mechanism reduces THD while maintaining relatively simple circuit architecture through intelligent control.

The patent dynamically adjusts switching frequency and timing based on load conditions. At light loads, it reduces switching frequency and synchronizes FET turn-on with zero current moments, achieving zero current switching that eliminates switching losses. This dynamic operation improves efficiency while keeping the control logic relatively simple through load-based adaptation.

The patent changes the switching frequency parameter based on load conditions. At light loads, the switching frequency is reduced to allow resonant current to decay to zero before switching, achieving zero current switching and minimizing switching losses. This parameter adjustment improves efficiency without fundamentally changing the circuit operation complexity.

The patent implements dynamic switching frequency adjustment based on load conditions. At light loads, the switching frequency is reduced to allow resonant current to complete its cycle and return to zero before the FET turns on. This dynamic control eliminates large current steps and reduces THD while maintaining relatively simple control logic through load-based frequency adaptation.

The patent uses feedback from resonant current detection to dynamically adjust switching timing and frequency. By monitoring the resonant current waveform and adapting the switch turn-on timing accordingly, the system eliminates current waveform distortion and reduces THD while keeping the control mechanism relatively simple through intelligent feedback-based timing adjustment.