Considerations Regarding the Relationship between Power Factor and Harmonic Distortions of Switched Mode Power Supplies
نویسندگان
چکیده
The main goal of this paper is to present some experimental results regarding power factor (PF) and current total harmonic distortions (THDi) of some very common loads on low voltage a.c. lines i.e. the power supply of computers, monitors and TV sets. The causes of some unexpected values are investigated and some physically meaningful explanations are delivered. The impact of the output current value on PF is emphasized thus proving that one single PF value cannot fully qualify a SMPS. It is also proven that harmonic analysis based THDi values may be very misleading if inter-harmonic components are neglected. Finally an old concept, of renewed interest, the dependency of THDi on PF is revisited.
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تاریخ انتشار 2012