Power Factor Decomposition in Unbalanced 3-Wire Sinusoidal Networks

The effective power factor of an unbalanced linear load that is fed by an unbalanced source is degraded by both the source and load unbalance. This paper attempts to partition the analytical expression of effective power factor and identify which elements are due to customer load and utility supply, for the purpose of billing. The effective power factor is expressed in terms of positive and negative sequence power factors and voltage and current unbalance factors. Such decomposition is greatly simplified in special cases where either the load or the source is balanced. Practical limitations for power factor partitioning are addressed. The work is illustrated by two sets of field measurements.