论文信息 - On the definition of power factor and apparent power in unbalanced polyphase circuits with sinusoidal voltage and currents

On the definition of power factor and apparent power in unbalanced polyphase circuits with sinusoidal voltage and currents

Definition for the apparent power S and for the power factor PF in unbalanced polyphase circuits with sinusoidal waveforms are presented. It is proved that the definition S/sup 2/=(V/sub a//sup 2/+V/sub b//sup 2/+V/sub c//sup 2/) (I/sub a//sup 2/+I/sub b//sup 2/+I/sub c//sup 2/) has a definite physical meaning, leading itself to a convenient resolution in positive, negative and zero sequence, nonactive and active power. It is suggested that the power factor be represented with the help of the ratio P/sup +//S, where P/sup +/ is the positive sequence active powers. >

A. E. Emanuel | A. Emanuel

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