Method and network for enhancing power factor of off-line switching circuit.

摘要

An arrangement for improving the power factor at the input of an off-line switching type power supply is operative to extend the duration of the pulse current conducted by the diode rectifiers. A parallel LC ringing circuit (413) is introduced between the AC line (401) and the rectifier (404) of the switching type power supply to enhance the voltage enabling conduction of the rectifying diodes and hence initiate current flow through the rectifying diodes earlier in each half cycle. This extends the conduction interval of the rectifying diodes significantly and enhances the power factor at the input to the switching type power supply.