Why is the power factor of traditional LED switching power supply relatively low?

The main reason for reducing the power factor is the existence of large electrolytic capacitors. Because of the capacitor, the voltage will not change suddenly, the voltage waveform is relatively smooth, and the current waveform is still similar to sine wave, so the power factor is relatively low.

At present, the LED driving power supply in the technology is driven by constant current, so there is no large electrolytic capacitor, so the power factor is relatively high, and many driving boards have added power factor correction.