Power factor measurement for rotating machines under system unbalance

Sequence powers are a form of electrical pollution for the vast majority of rotational loads, since these powers contribute to both line and machine losses. The negative sequence power resulting in counter-torque reduces useful work. Therefore, the negative sequence should be accounted for in the power factor calculations. In this paper, power factor is measured for a proposed power factor definition for treating unbalance under sinusoidal conditions. This is used to assess power quality at an industrial plant's mains. In addition, this proposed sinusoidal definition is extended to assess power factor for three-phase machines operating under system unbalance.