| 摘要 |
PURPOSE: A power factor improving circuit is provided to improve power factor of an AC input terminal for a power supply, but yet to prevent an additional power loss by forming the circuit using only a reactor and a capacitor. CONSTITUTION: The power factor improving circuit has input terminals(L11, L12)) for inputting AC voltage and a reactor(USR) for outputting ground current by grounding current generated when the AC voltage is inputted through the input terminal(L11). The AC voltage transmitted from the reactor(USR) is rectified by a bridge diode(BD), then outputted as a DC voltage. The DC voltage is smoothed by smoothing capacitors(C1, C2) coupled to the bridge diode(BD) in parallel. The ground current is compensated by a compensating capacitor(C3) such that a phase of the ground current becomes the same as the DC voltage when the ground current flows along the smoothing capacitors(C1, C2). The compensating capacitor(C3) is disposed between the input terminals(L11, L12) and the smoothing capacitors(C1, C2).
|
