Effect of Neutral Path Power Losses on the Apparent Power Definitions: A Preliminary Study

This paper presents the theoretical background needed to understand the effect of the parameters that affect the ratio rho between the equivalent neutral path resistance and line resistance of a transposed three-phase line. The ratio rho has a significant impact on the value of the apparent power as defined in IEEE Std. 1459. The ratio rho, however, depends on the topology of the power network as well as the type and size of the loads supplied by the feeder on which the apparent power is measured. It was found that for a wide range of conditions rho ap R ⁰/R ⁺, where R ⁰, R ⁺ are the zero- and positive-sequence resistances of the line supplying the observed load.